SELinux: merge policydb_index_classes and policydb_index_others
[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/kernel.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched.h>
31 #include <linux/security.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/swap.h>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.h>
47 #include <linux/netfilter_ipv4.h>
48 #include <linux/netfilter_ipv6.h>
49 #include <linux/tty.h>
50 #include <net/icmp.h>
51 #include <net/ip.h>             /* for local_port_range[] */
52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h>    /* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h>           /* for Unix socket types */
67 #include <net/af_unix.h>        /* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78 #include <linux/posix-timers.h>
79 #include <linux/syslog.h>
80
81 #include "avc.h"
82 #include "objsec.h"
83 #include "netif.h"
84 #include "netnode.h"
85 #include "netport.h"
86 #include "xfrm.h"
87 #include "netlabel.h"
88 #include "audit.h"
89
90 #define NUM_SEL_MNT_OPTS 5
91
92 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
93 extern struct security_operations *security_ops;
94
95 /* SECMARK reference count */
96 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
97
98 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
99 int selinux_enforcing;
100
101 static int __init enforcing_setup(char *str)
102 {
103         unsigned long enforcing;
104         if (!strict_strtoul(str, 0, &enforcing))
105                 selinux_enforcing = enforcing ? 1 : 0;
106         return 1;
107 }
108 __setup("enforcing=", enforcing_setup);
109 #endif
110
111 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
112 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
113
114 static int __init selinux_enabled_setup(char *str)
115 {
116         unsigned long enabled;
117         if (!strict_strtoul(str, 0, &enabled))
118                 selinux_enabled = enabled ? 1 : 0;
119         return 1;
120 }
121 __setup("selinux=", selinux_enabled_setup);
122 #else
123 int selinux_enabled = 1;
124 #endif
125
126 static struct kmem_cache *sel_inode_cache;
127
128 /**
129  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
130  *
131  * Description:
132  * This function checks the SECMARK reference counter to see if any SECMARK
133  * targets are currently configured, if the reference counter is greater than
134  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
135  * enabled, false (0) if SECMARK is disabled.
136  *
137  */
138 static int selinux_secmark_enabled(void)
139 {
140         return (atomic_read(&selinux_secmark_refcount) > 0);
141 }
142
143 /*
144  * initialise the security for the init task
145  */
146 static void cred_init_security(void)
147 {
148         struct cred *cred = (struct cred *) current->real_cred;
149         struct task_security_struct *tsec;
150
151         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
152         if (!tsec)
153                 panic("SELinux:  Failed to initialize initial task.\n");
154
155         tsec->osid = tsec->sid = SECINITSID_KERNEL;
156         cred->security = tsec;
157 }
158
159 /*
160  * get the security ID of a set of credentials
161  */
162 static inline u32 cred_sid(const struct cred *cred)
163 {
164         const struct task_security_struct *tsec;
165
166         tsec = cred->security;
167         return tsec->sid;
168 }
169
170 /*
171  * get the objective security ID of a task
172  */
173 static inline u32 task_sid(const struct task_struct *task)
174 {
175         u32 sid;
176
177         rcu_read_lock();
178         sid = cred_sid(__task_cred(task));
179         rcu_read_unlock();
180         return sid;
181 }
182
183 /*
184  * get the subjective security ID of the current task
185  */
186 static inline u32 current_sid(void)
187 {
188         const struct task_security_struct *tsec = current_security();
189
190         return tsec->sid;
191 }
192
193 /* Allocate and free functions for each kind of security blob. */
194
195 static int inode_alloc_security(struct inode *inode)
196 {
197         struct inode_security_struct *isec;
198         u32 sid = current_sid();
199
200         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
201         if (!isec)
202                 return -ENOMEM;
203
204         mutex_init(&isec->lock);
205         INIT_LIST_HEAD(&isec->list);
206         isec->inode = inode;
207         isec->sid = SECINITSID_UNLABELED;
208         isec->sclass = SECCLASS_FILE;
209         isec->task_sid = sid;
210         inode->i_security = isec;
211
212         return 0;
213 }
214
215 static void inode_free_security(struct inode *inode)
216 {
217         struct inode_security_struct *isec = inode->i_security;
218         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
219
220         spin_lock(&sbsec->isec_lock);
221         if (!list_empty(&isec->list))
222                 list_del_init(&isec->list);
223         spin_unlock(&sbsec->isec_lock);
224
225         inode->i_security = NULL;
226         kmem_cache_free(sel_inode_cache, isec);
227 }
228
229 static int file_alloc_security(struct file *file)
230 {
231         struct file_security_struct *fsec;
232         u32 sid = current_sid();
233
234         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
235         if (!fsec)
236                 return -ENOMEM;
237
238         fsec->sid = sid;
239         fsec->fown_sid = sid;
240         file->f_security = fsec;
241
242         return 0;
243 }
244
245 static void file_free_security(struct file *file)
246 {
247         struct file_security_struct *fsec = file->f_security;
248         file->f_security = NULL;
249         kfree(fsec);
250 }
251
252 static int superblock_alloc_security(struct super_block *sb)
253 {
254         struct superblock_security_struct *sbsec;
255
256         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
257         if (!sbsec)
258                 return -ENOMEM;
259
260         mutex_init(&sbsec->lock);
261         INIT_LIST_HEAD(&sbsec->isec_head);
262         spin_lock_init(&sbsec->isec_lock);
263         sbsec->sb = sb;
264         sbsec->sid = SECINITSID_UNLABELED;
265         sbsec->def_sid = SECINITSID_FILE;
266         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
267         sb->s_security = sbsec;
268
269         return 0;
270 }
271
272 static void superblock_free_security(struct super_block *sb)
273 {
274         struct superblock_security_struct *sbsec = sb->s_security;
275         sb->s_security = NULL;
276         kfree(sbsec);
277 }
278
279 /* The security server must be initialized before
280    any labeling or access decisions can be provided. */
281 extern int ss_initialized;
282
283 /* The file system's label must be initialized prior to use. */
284
285 static const char *labeling_behaviors[6] = {
286         "uses xattr",
287         "uses transition SIDs",
288         "uses task SIDs",
289         "uses genfs_contexts",
290         "not configured for labeling",
291         "uses mountpoint labeling",
292 };
293
294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
295
296 static inline int inode_doinit(struct inode *inode)
297 {
298         return inode_doinit_with_dentry(inode, NULL);
299 }
300
301 enum {
302         Opt_error = -1,
303         Opt_context = 1,
304         Opt_fscontext = 2,
305         Opt_defcontext = 3,
306         Opt_rootcontext = 4,
307         Opt_labelsupport = 5,
308 };
309
310 static const match_table_t tokens = {
311         {Opt_context, CONTEXT_STR "%s"},
312         {Opt_fscontext, FSCONTEXT_STR "%s"},
313         {Opt_defcontext, DEFCONTEXT_STR "%s"},
314         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
315         {Opt_labelsupport, LABELSUPP_STR},
316         {Opt_error, NULL},
317 };
318
319 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
320
321 static int may_context_mount_sb_relabel(u32 sid,
322                         struct superblock_security_struct *sbsec,
323                         const struct cred *cred)
324 {
325         const struct task_security_struct *tsec = cred->security;
326         int rc;
327
328         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
329                           FILESYSTEM__RELABELFROM, NULL);
330         if (rc)
331                 return rc;
332
333         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
334                           FILESYSTEM__RELABELTO, NULL);
335         return rc;
336 }
337
338 static int may_context_mount_inode_relabel(u32 sid,
339                         struct superblock_security_struct *sbsec,
340                         const struct cred *cred)
341 {
342         const struct task_security_struct *tsec = cred->security;
343         int rc;
344         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
345                           FILESYSTEM__RELABELFROM, NULL);
346         if (rc)
347                 return rc;
348
349         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
350                           FILESYSTEM__ASSOCIATE, NULL);
351         return rc;
352 }
353
354 static int sb_finish_set_opts(struct super_block *sb)
355 {
356         struct superblock_security_struct *sbsec = sb->s_security;
357         struct dentry *root = sb->s_root;
358         struct inode *root_inode = root->d_inode;
359         int rc = 0;
360
361         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
362                 /* Make sure that the xattr handler exists and that no
363                    error other than -ENODATA is returned by getxattr on
364                    the root directory.  -ENODATA is ok, as this may be
365                    the first boot of the SELinux kernel before we have
366                    assigned xattr values to the filesystem. */
367                 if (!root_inode->i_op->getxattr) {
368                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
369                                "xattr support\n", sb->s_id, sb->s_type->name);
370                         rc = -EOPNOTSUPP;
371                         goto out;
372                 }
373                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
374                 if (rc < 0 && rc != -ENODATA) {
375                         if (rc == -EOPNOTSUPP)
376                                 printk(KERN_WARNING "SELinux: (dev %s, type "
377                                        "%s) has no security xattr handler\n",
378                                        sb->s_id, sb->s_type->name);
379                         else
380                                 printk(KERN_WARNING "SELinux: (dev %s, type "
381                                        "%s) getxattr errno %d\n", sb->s_id,
382                                        sb->s_type->name, -rc);
383                         goto out;
384                 }
385         }
386
387         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
388
389         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
390                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
391                        sb->s_id, sb->s_type->name);
392         else
393                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
394                        sb->s_id, sb->s_type->name,
395                        labeling_behaviors[sbsec->behavior-1]);
396
397         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
398             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
399             sbsec->behavior == SECURITY_FS_USE_NONE ||
400             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
401                 sbsec->flags &= ~SE_SBLABELSUPP;
402
403         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
404         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
405                 sbsec->flags |= SE_SBLABELSUPP;
406
407         /* Initialize the root inode. */
408         rc = inode_doinit_with_dentry(root_inode, root);
409
410         /* Initialize any other inodes associated with the superblock, e.g.
411            inodes created prior to initial policy load or inodes created
412            during get_sb by a pseudo filesystem that directly
413            populates itself. */
414         spin_lock(&sbsec->isec_lock);
415 next_inode:
416         if (!list_empty(&sbsec->isec_head)) {
417                 struct inode_security_struct *isec =
418                                 list_entry(sbsec->isec_head.next,
419                                            struct inode_security_struct, list);
420                 struct inode *inode = isec->inode;
421                 spin_unlock(&sbsec->isec_lock);
422                 inode = igrab(inode);
423                 if (inode) {
424                         if (!IS_PRIVATE(inode))
425                                 inode_doinit(inode);
426                         iput(inode);
427                 }
428                 spin_lock(&sbsec->isec_lock);
429                 list_del_init(&isec->list);
430                 goto next_inode;
431         }
432         spin_unlock(&sbsec->isec_lock);
433 out:
434         return rc;
435 }
436
437 /*
438  * This function should allow an FS to ask what it's mount security
439  * options were so it can use those later for submounts, displaying
440  * mount options, or whatever.
441  */
442 static int selinux_get_mnt_opts(const struct super_block *sb,
443                                 struct security_mnt_opts *opts)
444 {
445         int rc = 0, i;
446         struct superblock_security_struct *sbsec = sb->s_security;
447         char *context = NULL;
448         u32 len;
449         char tmp;
450
451         security_init_mnt_opts(opts);
452
453         if (!(sbsec->flags & SE_SBINITIALIZED))
454                 return -EINVAL;
455
456         if (!ss_initialized)
457                 return -EINVAL;
458
459         tmp = sbsec->flags & SE_MNTMASK;
460         /* count the number of mount options for this sb */
461         for (i = 0; i < 8; i++) {
462                 if (tmp & 0x01)
463                         opts->num_mnt_opts++;
464                 tmp >>= 1;
465         }
466         /* Check if the Label support flag is set */
467         if (sbsec->flags & SE_SBLABELSUPP)
468                 opts->num_mnt_opts++;
469
470         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
471         if (!opts->mnt_opts) {
472                 rc = -ENOMEM;
473                 goto out_free;
474         }
475
476         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
477         if (!opts->mnt_opts_flags) {
478                 rc = -ENOMEM;
479                 goto out_free;
480         }
481
482         i = 0;
483         if (sbsec->flags & FSCONTEXT_MNT) {
484                 rc = security_sid_to_context(sbsec->sid, &context, &len);
485                 if (rc)
486                         goto out_free;
487                 opts->mnt_opts[i] = context;
488                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
489         }
490         if (sbsec->flags & CONTEXT_MNT) {
491                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
492                 if (rc)
493                         goto out_free;
494                 opts->mnt_opts[i] = context;
495                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
496         }
497         if (sbsec->flags & DEFCONTEXT_MNT) {
498                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
499                 if (rc)
500                         goto out_free;
501                 opts->mnt_opts[i] = context;
502                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
503         }
504         if (sbsec->flags & ROOTCONTEXT_MNT) {
505                 struct inode *root = sbsec->sb->s_root->d_inode;
506                 struct inode_security_struct *isec = root->i_security;
507
508                 rc = security_sid_to_context(isec->sid, &context, &len);
509                 if (rc)
510                         goto out_free;
511                 opts->mnt_opts[i] = context;
512                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
513         }
514         if (sbsec->flags & SE_SBLABELSUPP) {
515                 opts->mnt_opts[i] = NULL;
516                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
517         }
518
519         BUG_ON(i != opts->num_mnt_opts);
520
521         return 0;
522
523 out_free:
524         security_free_mnt_opts(opts);
525         return rc;
526 }
527
528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
529                       u32 old_sid, u32 new_sid)
530 {
531         char mnt_flags = sbsec->flags & SE_MNTMASK;
532
533         /* check if the old mount command had the same options */
534         if (sbsec->flags & SE_SBINITIALIZED)
535                 if (!(sbsec->flags & flag) ||
536                     (old_sid != new_sid))
537                         return 1;
538
539         /* check if we were passed the same options twice,
540          * aka someone passed context=a,context=b
541          */
542         if (!(sbsec->flags & SE_SBINITIALIZED))
543                 if (mnt_flags & flag)
544                         return 1;
545         return 0;
546 }
547
548 /*
549  * Allow filesystems with binary mount data to explicitly set mount point
550  * labeling information.
551  */
552 static int selinux_set_mnt_opts(struct super_block *sb,
553                                 struct security_mnt_opts *opts)
554 {
555         const struct cred *cred = current_cred();
556         int rc = 0, i;
557         struct superblock_security_struct *sbsec = sb->s_security;
558         const char *name = sb->s_type->name;
559         struct inode *inode = sbsec->sb->s_root->d_inode;
560         struct inode_security_struct *root_isec = inode->i_security;
561         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
562         u32 defcontext_sid = 0;
563         char **mount_options = opts->mnt_opts;
564         int *flags = opts->mnt_opts_flags;
565         int num_opts = opts->num_mnt_opts;
566
567         mutex_lock(&sbsec->lock);
568
569         if (!ss_initialized) {
570                 if (!num_opts) {
571                         /* Defer initialization until selinux_complete_init,
572                            after the initial policy is loaded and the security
573                            server is ready to handle calls. */
574                         goto out;
575                 }
576                 rc = -EINVAL;
577                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
578                         "before the security server is initialized\n");
579                 goto out;
580         }
581
582         /*
583          * Binary mount data FS will come through this function twice.  Once
584          * from an explicit call and once from the generic calls from the vfs.
585          * Since the generic VFS calls will not contain any security mount data
586          * we need to skip the double mount verification.
587          *
588          * This does open a hole in which we will not notice if the first
589          * mount using this sb set explict options and a second mount using
590          * this sb does not set any security options.  (The first options
591          * will be used for both mounts)
592          */
593         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
594             && (num_opts == 0))
595                 goto out;
596
597         /*
598          * parse the mount options, check if they are valid sids.
599          * also check if someone is trying to mount the same sb more
600          * than once with different security options.
601          */
602         for (i = 0; i < num_opts; i++) {
603                 u32 sid;
604
605                 if (flags[i] == SE_SBLABELSUPP)
606                         continue;
607                 rc = security_context_to_sid(mount_options[i],
608                                              strlen(mount_options[i]), &sid);
609                 if (rc) {
610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
612                                mount_options[i], sb->s_id, name, rc);
613                         goto out;
614                 }
615                 switch (flags[i]) {
616                 case FSCONTEXT_MNT:
617                         fscontext_sid = sid;
618
619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620                                         fscontext_sid))
621                                 goto out_double_mount;
622
623                         sbsec->flags |= FSCONTEXT_MNT;
624                         break;
625                 case CONTEXT_MNT:
626                         context_sid = sid;
627
628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629                                         context_sid))
630                                 goto out_double_mount;
631
632                         sbsec->flags |= CONTEXT_MNT;
633                         break;
634                 case ROOTCONTEXT_MNT:
635                         rootcontext_sid = sid;
636
637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638                                         rootcontext_sid))
639                                 goto out_double_mount;
640
641                         sbsec->flags |= ROOTCONTEXT_MNT;
642
643                         break;
644                 case DEFCONTEXT_MNT:
645                         defcontext_sid = sid;
646
647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648                                         defcontext_sid))
649                                 goto out_double_mount;
650
651                         sbsec->flags |= DEFCONTEXT_MNT;
652
653                         break;
654                 default:
655                         rc = -EINVAL;
656                         goto out;
657                 }
658         }
659
660         if (sbsec->flags & SE_SBINITIALIZED) {
661                 /* previously mounted with options, but not on this attempt? */
662                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
663                         goto out_double_mount;
664                 rc = 0;
665                 goto out;
666         }
667
668         if (strcmp(sb->s_type->name, "proc") == 0)
669                 sbsec->flags |= SE_SBPROC;
670
671         /* Determine the labeling behavior to use for this filesystem type. */
672         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673         if (rc) {
674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675                        __func__, sb->s_type->name, rc);
676                 goto out;
677         }
678
679         /* sets the context of the superblock for the fs being mounted. */
680         if (fscontext_sid) {
681                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
682                 if (rc)
683                         goto out;
684
685                 sbsec->sid = fscontext_sid;
686         }
687
688         /*
689          * Switch to using mount point labeling behavior.
690          * sets the label used on all file below the mountpoint, and will set
691          * the superblock context if not already set.
692          */
693         if (context_sid) {
694                 if (!fscontext_sid) {
695                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
696                                                           cred);
697                         if (rc)
698                                 goto out;
699                         sbsec->sid = context_sid;
700                 } else {
701                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
702                                                              cred);
703                         if (rc)
704                                 goto out;
705                 }
706                 if (!rootcontext_sid)
707                         rootcontext_sid = context_sid;
708
709                 sbsec->mntpoint_sid = context_sid;
710                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
711         }
712
713         if (rootcontext_sid) {
714                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
715                                                      cred);
716                 if (rc)
717                         goto out;
718
719                 root_isec->sid = rootcontext_sid;
720                 root_isec->initialized = 1;
721         }
722
723         if (defcontext_sid) {
724                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
725                         rc = -EINVAL;
726                         printk(KERN_WARNING "SELinux: defcontext option is "
727                                "invalid for this filesystem type\n");
728                         goto out;
729                 }
730
731                 if (defcontext_sid != sbsec->def_sid) {
732                         rc = may_context_mount_inode_relabel(defcontext_sid,
733                                                              sbsec, cred);
734                         if (rc)
735                                 goto out;
736                 }
737
738                 sbsec->def_sid = defcontext_sid;
739         }
740
741         rc = sb_finish_set_opts(sb);
742 out:
743         mutex_unlock(&sbsec->lock);
744         return rc;
745 out_double_mount:
746         rc = -EINVAL;
747         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
748                "security settings for (dev %s, type %s)\n", sb->s_id, name);
749         goto out;
750 }
751
752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
753                                         struct super_block *newsb)
754 {
755         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
756         struct superblock_security_struct *newsbsec = newsb->s_security;
757
758         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
759         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
760         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
761
762         /*
763          * if the parent was able to be mounted it clearly had no special lsm
764          * mount options.  thus we can safely deal with this superblock later
765          */
766         if (!ss_initialized)
767                 return;
768
769         /* how can we clone if the old one wasn't set up?? */
770         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
771
772         /* if fs is reusing a sb, just let its options stand... */
773         if (newsbsec->flags & SE_SBINITIALIZED)
774                 return;
775
776         mutex_lock(&newsbsec->lock);
777
778         newsbsec->flags = oldsbsec->flags;
779
780         newsbsec->sid = oldsbsec->sid;
781         newsbsec->def_sid = oldsbsec->def_sid;
782         newsbsec->behavior = oldsbsec->behavior;
783
784         if (set_context) {
785                 u32 sid = oldsbsec->mntpoint_sid;
786
787                 if (!set_fscontext)
788                         newsbsec->sid = sid;
789                 if (!set_rootcontext) {
790                         struct inode *newinode = newsb->s_root->d_inode;
791                         struct inode_security_struct *newisec = newinode->i_security;
792                         newisec->sid = sid;
793                 }
794                 newsbsec->mntpoint_sid = sid;
795         }
796         if (set_rootcontext) {
797                 const struct inode *oldinode = oldsb->s_root->d_inode;
798                 const struct inode_security_struct *oldisec = oldinode->i_security;
799                 struct inode *newinode = newsb->s_root->d_inode;
800                 struct inode_security_struct *newisec = newinode->i_security;
801
802                 newisec->sid = oldisec->sid;
803         }
804
805         sb_finish_set_opts(newsb);
806         mutex_unlock(&newsbsec->lock);
807 }
808
809 static int selinux_parse_opts_str(char *options,
810                                   struct security_mnt_opts *opts)
811 {
812         char *p;
813         char *context = NULL, *defcontext = NULL;
814         char *fscontext = NULL, *rootcontext = NULL;
815         int rc, num_mnt_opts = 0;
816
817         opts->num_mnt_opts = 0;
818
819         /* Standard string-based options. */
820         while ((p = strsep(&options, "|")) != NULL) {
821                 int token;
822                 substring_t args[MAX_OPT_ARGS];
823
824                 if (!*p)
825                         continue;
826
827                 token = match_token(p, tokens, args);
828
829                 switch (token) {
830                 case Opt_context:
831                         if (context || defcontext) {
832                                 rc = -EINVAL;
833                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
834                                 goto out_err;
835                         }
836                         context = match_strdup(&args[0]);
837                         if (!context) {
838                                 rc = -ENOMEM;
839                                 goto out_err;
840                         }
841                         break;
842
843                 case Opt_fscontext:
844                         if (fscontext) {
845                                 rc = -EINVAL;
846                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
847                                 goto out_err;
848                         }
849                         fscontext = match_strdup(&args[0]);
850                         if (!fscontext) {
851                                 rc = -ENOMEM;
852                                 goto out_err;
853                         }
854                         break;
855
856                 case Opt_rootcontext:
857                         if (rootcontext) {
858                                 rc = -EINVAL;
859                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
860                                 goto out_err;
861                         }
862                         rootcontext = match_strdup(&args[0]);
863                         if (!rootcontext) {
864                                 rc = -ENOMEM;
865                                 goto out_err;
866                         }
867                         break;
868
869                 case Opt_defcontext:
870                         if (context || defcontext) {
871                                 rc = -EINVAL;
872                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
873                                 goto out_err;
874                         }
875                         defcontext = match_strdup(&args[0]);
876                         if (!defcontext) {
877                                 rc = -ENOMEM;
878                                 goto out_err;
879                         }
880                         break;
881                 case Opt_labelsupport:
882                         break;
883                 default:
884                         rc = -EINVAL;
885                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
886                         goto out_err;
887
888                 }
889         }
890
891         rc = -ENOMEM;
892         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
893         if (!opts->mnt_opts)
894                 goto out_err;
895
896         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
897         if (!opts->mnt_opts_flags) {
898                 kfree(opts->mnt_opts);
899                 goto out_err;
900         }
901
902         if (fscontext) {
903                 opts->mnt_opts[num_mnt_opts] = fscontext;
904                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
905         }
906         if (context) {
907                 opts->mnt_opts[num_mnt_opts] = context;
908                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
909         }
910         if (rootcontext) {
911                 opts->mnt_opts[num_mnt_opts] = rootcontext;
912                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
913         }
914         if (defcontext) {
915                 opts->mnt_opts[num_mnt_opts] = defcontext;
916                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
917         }
918
919         opts->num_mnt_opts = num_mnt_opts;
920         return 0;
921
922 out_err:
923         kfree(context);
924         kfree(defcontext);
925         kfree(fscontext);
926         kfree(rootcontext);
927         return rc;
928 }
929 /*
930  * string mount options parsing and call set the sbsec
931  */
932 static int superblock_doinit(struct super_block *sb, void *data)
933 {
934         int rc = 0;
935         char *options = data;
936         struct security_mnt_opts opts;
937
938         security_init_mnt_opts(&opts);
939
940         if (!data)
941                 goto out;
942
943         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
944
945         rc = selinux_parse_opts_str(options, &opts);
946         if (rc)
947                 goto out_err;
948
949 out:
950         rc = selinux_set_mnt_opts(sb, &opts);
951
952 out_err:
953         security_free_mnt_opts(&opts);
954         return rc;
955 }
956
957 static void selinux_write_opts(struct seq_file *m,
958                                struct security_mnt_opts *opts)
959 {
960         int i;
961         char *prefix;
962
963         for (i = 0; i < opts->num_mnt_opts; i++) {
964                 char *has_comma;
965
966                 if (opts->mnt_opts[i])
967                         has_comma = strchr(opts->mnt_opts[i], ',');
968                 else
969                         has_comma = NULL;
970
971                 switch (opts->mnt_opts_flags[i]) {
972                 case CONTEXT_MNT:
973                         prefix = CONTEXT_STR;
974                         break;
975                 case FSCONTEXT_MNT:
976                         prefix = FSCONTEXT_STR;
977                         break;
978                 case ROOTCONTEXT_MNT:
979                         prefix = ROOTCONTEXT_STR;
980                         break;
981                 case DEFCONTEXT_MNT:
982                         prefix = DEFCONTEXT_STR;
983                         break;
984                 case SE_SBLABELSUPP:
985                         seq_putc(m, ',');
986                         seq_puts(m, LABELSUPP_STR);
987                         continue;
988                 default:
989                         BUG();
990                 };
991                 /* we need a comma before each option */
992                 seq_putc(m, ',');
993                 seq_puts(m, prefix);
994                 if (has_comma)
995                         seq_putc(m, '\"');
996                 seq_puts(m, opts->mnt_opts[i]);
997                 if (has_comma)
998                         seq_putc(m, '\"');
999         }
1000 }
1001
1002 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1003 {
1004         struct security_mnt_opts opts;
1005         int rc;
1006
1007         rc = selinux_get_mnt_opts(sb, &opts);
1008         if (rc) {
1009                 /* before policy load we may get EINVAL, don't show anything */
1010                 if (rc == -EINVAL)
1011                         rc = 0;
1012                 return rc;
1013         }
1014
1015         selinux_write_opts(m, &opts);
1016
1017         security_free_mnt_opts(&opts);
1018
1019         return rc;
1020 }
1021
1022 static inline u16 inode_mode_to_security_class(umode_t mode)
1023 {
1024         switch (mode & S_IFMT) {
1025         case S_IFSOCK:
1026                 return SECCLASS_SOCK_FILE;
1027         case S_IFLNK:
1028                 return SECCLASS_LNK_FILE;
1029         case S_IFREG:
1030                 return SECCLASS_FILE;
1031         case S_IFBLK:
1032                 return SECCLASS_BLK_FILE;
1033         case S_IFDIR:
1034                 return SECCLASS_DIR;
1035         case S_IFCHR:
1036                 return SECCLASS_CHR_FILE;
1037         case S_IFIFO:
1038                 return SECCLASS_FIFO_FILE;
1039
1040         }
1041
1042         return SECCLASS_FILE;
1043 }
1044
1045 static inline int default_protocol_stream(int protocol)
1046 {
1047         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1048 }
1049
1050 static inline int default_protocol_dgram(int protocol)
1051 {
1052         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1053 }
1054
1055 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1056 {
1057         switch (family) {
1058         case PF_UNIX:
1059                 switch (type) {
1060                 case SOCK_STREAM:
1061                 case SOCK_SEQPACKET:
1062                         return SECCLASS_UNIX_STREAM_SOCKET;
1063                 case SOCK_DGRAM:
1064                         return SECCLASS_UNIX_DGRAM_SOCKET;
1065                 }
1066                 break;
1067         case PF_INET:
1068         case PF_INET6:
1069                 switch (type) {
1070                 case SOCK_STREAM:
1071                         if (default_protocol_stream(protocol))
1072                                 return SECCLASS_TCP_SOCKET;
1073                         else
1074                                 return SECCLASS_RAWIP_SOCKET;
1075                 case SOCK_DGRAM:
1076                         if (default_protocol_dgram(protocol))
1077                                 return SECCLASS_UDP_SOCKET;
1078                         else
1079                                 return SECCLASS_RAWIP_SOCKET;
1080                 case SOCK_DCCP:
1081                         return SECCLASS_DCCP_SOCKET;
1082                 default:
1083                         return SECCLASS_RAWIP_SOCKET;
1084                 }
1085                 break;
1086         case PF_NETLINK:
1087                 switch (protocol) {
1088                 case NETLINK_ROUTE:
1089                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1090                 case NETLINK_FIREWALL:
1091                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1092                 case NETLINK_INET_DIAG:
1093                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1094                 case NETLINK_NFLOG:
1095                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1096                 case NETLINK_XFRM:
1097                         return SECCLASS_NETLINK_XFRM_SOCKET;
1098                 case NETLINK_SELINUX:
1099                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1100                 case NETLINK_AUDIT:
1101                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1102                 case NETLINK_IP6_FW:
1103                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1104                 case NETLINK_DNRTMSG:
1105                         return SECCLASS_NETLINK_DNRT_SOCKET;
1106                 case NETLINK_KOBJECT_UEVENT:
1107                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1108                 default:
1109                         return SECCLASS_NETLINK_SOCKET;
1110                 }
1111         case PF_PACKET:
1112                 return SECCLASS_PACKET_SOCKET;
1113         case PF_KEY:
1114                 return SECCLASS_KEY_SOCKET;
1115         case PF_APPLETALK:
1116                 return SECCLASS_APPLETALK_SOCKET;
1117         }
1118
1119         return SECCLASS_SOCKET;
1120 }
1121
1122 #ifdef CONFIG_PROC_FS
1123 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1124                                 u16 tclass,
1125                                 u32 *sid)
1126 {
1127         int buflen, rc;
1128         char *buffer, *path, *end;
1129
1130         buffer = (char *)__get_free_page(GFP_KERNEL);
1131         if (!buffer)
1132                 return -ENOMEM;
1133
1134         buflen = PAGE_SIZE;
1135         end = buffer+buflen;
1136         *--end = '\0';
1137         buflen--;
1138         path = end-1;
1139         *path = '/';
1140         while (de && de != de->parent) {
1141                 buflen -= de->namelen + 1;
1142                 if (buflen < 0)
1143                         break;
1144                 end -= de->namelen;
1145                 memcpy(end, de->name, de->namelen);
1146                 *--end = '/';
1147                 path = end;
1148                 de = de->parent;
1149         }
1150         rc = security_genfs_sid("proc", path, tclass, sid);
1151         free_page((unsigned long)buffer);
1152         return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct proc_dir_entry *de,
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,
1304                                              sbsec->sid,
1305                                              isec->sclass,
1306                                              &sid);
1307                 if (rc)
1308                         goto out_unlock;
1309                 isec->sid = sid;
1310                 break;
1311         case SECURITY_FS_USE_MNTPOINT:
1312                 isec->sid = sbsec->mntpoint_sid;
1313                 break;
1314         default:
1315                 /* Default to the fs superblock SID. */
1316                 isec->sid = sbsec->sid;
1317
1318                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1319                         struct proc_inode *proci = PROC_I(inode);
1320                         if (proci->pde) {
1321                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1322                                 rc = selinux_proc_get_sid(proci->pde,
1323                                                           isec->sclass,
1324                                                           &sid);
1325                                 if (rc)
1326                                         goto out_unlock;
1327                                 isec->sid = sid;
1328                         }
1329                 }
1330                 break;
1331         }
1332
1333         isec->initialized = 1;
1334
1335 out_unlock:
1336         mutex_unlock(&isec->lock);
1337 out:
1338         if (isec->sclass == SECCLASS_FILE)
1339                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1340         return rc;
1341 }
1342
1343 /* Convert a Linux signal to an access vector. */
1344 static inline u32 signal_to_av(int sig)
1345 {
1346         u32 perm = 0;
1347
1348         switch (sig) {
1349         case SIGCHLD:
1350                 /* Commonly granted from child to parent. */
1351                 perm = PROCESS__SIGCHLD;
1352                 break;
1353         case SIGKILL:
1354                 /* Cannot be caught or ignored */
1355                 perm = PROCESS__SIGKILL;
1356                 break;
1357         case SIGSTOP:
1358                 /* Cannot be caught or ignored */
1359                 perm = PROCESS__SIGSTOP;
1360                 break;
1361         default:
1362                 /* All other signals. */
1363                 perm = PROCESS__SIGNAL;
1364                 break;
1365         }
1366
1367         return perm;
1368 }
1369
1370 /*
1371  * Check permission between a pair of credentials
1372  * fork check, ptrace check, etc.
1373  */
1374 static int cred_has_perm(const struct cred *actor,
1375                          const struct cred *target,
1376                          u32 perms)
1377 {
1378         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1379
1380         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1381 }
1382
1383 /*
1384  * Check permission between a pair of tasks, e.g. signal checks,
1385  * fork check, ptrace check, etc.
1386  * tsk1 is the actor and tsk2 is the target
1387  * - this uses the default subjective creds of tsk1
1388  */
1389 static int task_has_perm(const struct task_struct *tsk1,
1390                          const struct task_struct *tsk2,
1391                          u32 perms)
1392 {
1393         const struct task_security_struct *__tsec1, *__tsec2;
1394         u32 sid1, sid2;
1395
1396         rcu_read_lock();
1397         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1398         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1399         rcu_read_unlock();
1400         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1401 }
1402
1403 /*
1404  * Check permission between current and another task, e.g. signal checks,
1405  * fork check, ptrace check, etc.
1406  * current is the actor and tsk2 is the target
1407  * - this uses current's subjective creds
1408  */
1409 static int current_has_perm(const struct task_struct *tsk,
1410                             u32 perms)
1411 {
1412         u32 sid, tsid;
1413
1414         sid = current_sid();
1415         tsid = task_sid(tsk);
1416         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1417 }
1418
1419 #if CAP_LAST_CAP > 63
1420 #error Fix SELinux to handle capabilities > 63.
1421 #endif
1422
1423 /* Check whether a task is allowed to use a capability. */
1424 static int task_has_capability(struct task_struct *tsk,
1425                                const struct cred *cred,
1426                                int cap, int audit)
1427 {
1428         struct common_audit_data ad;
1429         struct av_decision avd;
1430         u16 sclass;
1431         u32 sid = cred_sid(cred);
1432         u32 av = CAP_TO_MASK(cap);
1433         int rc;
1434
1435         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1436         ad.tsk = tsk;
1437         ad.u.cap = cap;
1438
1439         switch (CAP_TO_INDEX(cap)) {
1440         case 0:
1441                 sclass = SECCLASS_CAPABILITY;
1442                 break;
1443         case 1:
1444                 sclass = SECCLASS_CAPABILITY2;
1445                 break;
1446         default:
1447                 printk(KERN_ERR
1448                        "SELinux:  out of range capability %d\n", cap);
1449                 BUG();
1450         }
1451
1452         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1453         if (audit == SECURITY_CAP_AUDIT)
1454                 avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1455         return rc;
1456 }
1457
1458 /* Check whether a task is allowed to use a system operation. */
1459 static int task_has_system(struct task_struct *tsk,
1460                            u32 perms)
1461 {
1462         u32 sid = task_sid(tsk);
1463
1464         return avc_has_perm(sid, SECINITSID_KERNEL,
1465                             SECCLASS_SYSTEM, perms, NULL);
1466 }
1467
1468 /* Check whether a task has a particular permission to an inode.
1469    The 'adp' parameter is optional and allows other audit
1470    data to be passed (e.g. the dentry). */
1471 static int inode_has_perm(const struct cred *cred,
1472                           struct inode *inode,
1473                           u32 perms,
1474                           struct common_audit_data *adp)
1475 {
1476         struct inode_security_struct *isec;
1477         struct common_audit_data ad;
1478         u32 sid;
1479
1480         validate_creds(cred);
1481
1482         if (unlikely(IS_PRIVATE(inode)))
1483                 return 0;
1484
1485         sid = cred_sid(cred);
1486         isec = inode->i_security;
1487
1488         if (!adp) {
1489                 adp = &ad;
1490                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1491                 ad.u.fs.inode = inode;
1492         }
1493
1494         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1495 }
1496
1497 /* Same as inode_has_perm, but pass explicit audit data containing
1498    the dentry to help the auditing code to more easily generate the
1499    pathname if needed. */
1500 static inline int dentry_has_perm(const struct cred *cred,
1501                                   struct vfsmount *mnt,
1502                                   struct dentry *dentry,
1503                                   u32 av)
1504 {
1505         struct inode *inode = dentry->d_inode;
1506         struct common_audit_data ad;
1507
1508         COMMON_AUDIT_DATA_INIT(&ad, FS);
1509         ad.u.fs.path.mnt = mnt;
1510         ad.u.fs.path.dentry = dentry;
1511         return inode_has_perm(cred, inode, av, &ad);
1512 }
1513
1514 /* Check whether a task can use an open file descriptor to
1515    access an inode in a given way.  Check access to the
1516    descriptor itself, and then use dentry_has_perm to
1517    check a particular permission to the file.
1518    Access to the descriptor is implicitly granted if it
1519    has the same SID as the process.  If av is zero, then
1520    access to the file is not checked, e.g. for cases
1521    where only the descriptor is affected like seek. */
1522 static int file_has_perm(const struct cred *cred,
1523                          struct file *file,
1524                          u32 av)
1525 {
1526         struct file_security_struct *fsec = file->f_security;
1527         struct inode *inode = file->f_path.dentry->d_inode;
1528         struct common_audit_data ad;
1529         u32 sid = cred_sid(cred);
1530         int rc;
1531
1532         COMMON_AUDIT_DATA_INIT(&ad, FS);
1533         ad.u.fs.path = file->f_path;
1534
1535         if (sid != fsec->sid) {
1536                 rc = avc_has_perm(sid, fsec->sid,
1537                                   SECCLASS_FD,
1538                                   FD__USE,
1539                                   &ad);
1540                 if (rc)
1541                         goto out;
1542         }
1543
1544         /* av is zero if only checking access to the descriptor. */
1545         rc = 0;
1546         if (av)
1547                 rc = inode_has_perm(cred, inode, av, &ad);
1548
1549 out:
1550         return rc;
1551 }
1552
1553 /* Check whether a task can create a file. */
1554 static int may_create(struct inode *dir,
1555                       struct dentry *dentry,
1556                       u16 tclass)
1557 {
1558         const struct task_security_struct *tsec = current_security();
1559         struct inode_security_struct *dsec;
1560         struct superblock_security_struct *sbsec;
1561         u32 sid, newsid;
1562         struct common_audit_data ad;
1563         int rc;
1564
1565         dsec = dir->i_security;
1566         sbsec = dir->i_sb->s_security;
1567
1568         sid = tsec->sid;
1569         newsid = tsec->create_sid;
1570
1571         COMMON_AUDIT_DATA_INIT(&ad, FS);
1572         ad.u.fs.path.dentry = dentry;
1573
1574         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1575                           DIR__ADD_NAME | DIR__SEARCH,
1576                           &ad);
1577         if (rc)
1578                 return rc;
1579
1580         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1581                 rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
1582                 if (rc)
1583                         return rc;
1584         }
1585
1586         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1587         if (rc)
1588                 return rc;
1589
1590         return avc_has_perm(newsid, sbsec->sid,
1591                             SECCLASS_FILESYSTEM,
1592                             FILESYSTEM__ASSOCIATE, &ad);
1593 }
1594
1595 /* Check whether a task can create a key. */
1596 static int may_create_key(u32 ksid,
1597                           struct task_struct *ctx)
1598 {
1599         u32 sid = task_sid(ctx);
1600
1601         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1602 }
1603
1604 #define MAY_LINK        0
1605 #define MAY_UNLINK      1
1606 #define MAY_RMDIR       2
1607
1608 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1609 static int may_link(struct inode *dir,
1610                     struct dentry *dentry,
1611                     int kind)
1612
1613 {
1614         struct inode_security_struct *dsec, *isec;
1615         struct common_audit_data ad;
1616         u32 sid = current_sid();
1617         u32 av;
1618         int rc;
1619
1620         dsec = dir->i_security;
1621         isec = dentry->d_inode->i_security;
1622
1623         COMMON_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         av = DIR__SEARCH;
1627         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1628         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631
1632         switch (kind) {
1633         case MAY_LINK:
1634                 av = FILE__LINK;
1635                 break;
1636         case MAY_UNLINK:
1637                 av = FILE__UNLINK;
1638                 break;
1639         case MAY_RMDIR:
1640                 av = DIR__RMDIR;
1641                 break;
1642         default:
1643                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1644                         __func__, kind);
1645                 return 0;
1646         }
1647
1648         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1649         return rc;
1650 }
1651
1652 static inline int may_rename(struct inode *old_dir,
1653                              struct dentry *old_dentry,
1654                              struct inode *new_dir,
1655                              struct dentry *new_dentry)
1656 {
1657         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1658         struct common_audit_data ad;
1659         u32 sid = current_sid();
1660         u32 av;
1661         int old_is_dir, new_is_dir;
1662         int rc;
1663
1664         old_dsec = old_dir->i_security;
1665         old_isec = old_dentry->d_inode->i_security;
1666         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1667         new_dsec = new_dir->i_security;
1668
1669         COMMON_AUDIT_DATA_INIT(&ad, FS);
1670
1671         ad.u.fs.path.dentry = old_dentry;
1672         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1673                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1674         if (rc)
1675                 return rc;
1676         rc = avc_has_perm(sid, old_isec->sid,
1677                           old_isec->sclass, FILE__RENAME, &ad);
1678         if (rc)
1679                 return rc;
1680         if (old_is_dir && new_dir != old_dir) {
1681                 rc = avc_has_perm(sid, old_isec->sid,
1682                                   old_isec->sclass, DIR__REPARENT, &ad);
1683                 if (rc)
1684                         return rc;
1685         }
1686
1687         ad.u.fs.path.dentry = new_dentry;
1688         av = DIR__ADD_NAME | DIR__SEARCH;
1689         if (new_dentry->d_inode)
1690                 av |= DIR__REMOVE_NAME;
1691         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1692         if (rc)
1693                 return rc;
1694         if (new_dentry->d_inode) {
1695                 new_isec = new_dentry->d_inode->i_security;
1696                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1697                 rc = avc_has_perm(sid, new_isec->sid,
1698                                   new_isec->sclass,
1699                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1700                 if (rc)
1701                         return rc;
1702         }
1703
1704         return 0;
1705 }
1706
1707 /* Check whether a task can perform a filesystem operation. */
1708 static int superblock_has_perm(const struct cred *cred,
1709                                struct super_block *sb,
1710                                u32 perms,
1711                                struct common_audit_data *ad)
1712 {
1713         struct superblock_security_struct *sbsec;
1714         u32 sid = cred_sid(cred);
1715
1716         sbsec = sb->s_security;
1717         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1718 }
1719
1720 /* Convert a Linux mode and permission mask to an access vector. */
1721 static inline u32 file_mask_to_av(int mode, int mask)
1722 {
1723         u32 av = 0;
1724
1725         if ((mode & S_IFMT) != S_IFDIR) {
1726                 if (mask & MAY_EXEC)
1727                         av |= FILE__EXECUTE;
1728                 if (mask & MAY_READ)
1729                         av |= FILE__READ;
1730
1731                 if (mask & MAY_APPEND)
1732                         av |= FILE__APPEND;
1733                 else if (mask & MAY_WRITE)
1734                         av |= FILE__WRITE;
1735
1736         } else {
1737                 if (mask & MAY_EXEC)
1738                         av |= DIR__SEARCH;
1739                 if (mask & MAY_WRITE)
1740                         av |= DIR__WRITE;
1741                 if (mask & MAY_READ)
1742                         av |= DIR__READ;
1743         }
1744
1745         return av;
1746 }
1747
1748 /* Convert a Linux file to an access vector. */
1749 static inline u32 file_to_av(struct file *file)
1750 {
1751         u32 av = 0;
1752
1753         if (file->f_mode & FMODE_READ)
1754                 av |= FILE__READ;
1755         if (file->f_mode & FMODE_WRITE) {
1756                 if (file->f_flags & O_APPEND)
1757                         av |= FILE__APPEND;
1758                 else
1759                         av |= FILE__WRITE;
1760         }
1761         if (!av) {
1762                 /*
1763                  * Special file opened with flags 3 for ioctl-only use.
1764                  */
1765                 av = FILE__IOCTL;
1766         }
1767
1768         return av;
1769 }
1770
1771 /*
1772  * Convert a file to an access vector and include the correct open
1773  * open permission.
1774  */
1775 static inline u32 open_file_to_av(struct file *file)
1776 {
1777         u32 av = file_to_av(file);
1778
1779         if (selinux_policycap_openperm)
1780                 av |= FILE__OPEN;
1781
1782         return av;
1783 }
1784
1785 /* Hook functions begin here. */
1786
1787 static int selinux_ptrace_access_check(struct task_struct *child,
1788                                      unsigned int mode)
1789 {
1790         int rc;
1791
1792         rc = cap_ptrace_access_check(child, mode);
1793         if (rc)
1794                 return rc;
1795
1796         if (mode == PTRACE_MODE_READ) {
1797                 u32 sid = current_sid();
1798                 u32 csid = task_sid(child);
1799                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1800         }
1801
1802         return current_has_perm(child, PROCESS__PTRACE);
1803 }
1804
1805 static int selinux_ptrace_traceme(struct task_struct *parent)
1806 {
1807         int rc;
1808
1809         rc = cap_ptrace_traceme(parent);
1810         if (rc)
1811                 return rc;
1812
1813         return task_has_perm(parent, current, PROCESS__PTRACE);
1814 }
1815
1816 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1817                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1818 {
1819         int error;
1820
1821         error = current_has_perm(target, PROCESS__GETCAP);
1822         if (error)
1823                 return error;
1824
1825         return cap_capget(target, effective, inheritable, permitted);
1826 }
1827
1828 static int selinux_capset(struct cred *new, const struct cred *old,
1829                           const kernel_cap_t *effective,
1830                           const kernel_cap_t *inheritable,
1831                           const kernel_cap_t *permitted)
1832 {
1833         int error;
1834
1835         error = cap_capset(new, old,
1836                                       effective, inheritable, permitted);
1837         if (error)
1838                 return error;
1839
1840         return cred_has_perm(old, new, PROCESS__SETCAP);
1841 }
1842
1843 /*
1844  * (This comment used to live with the selinux_task_setuid hook,
1845  * which was removed).
1846  *
1847  * Since setuid only affects the current process, and since the SELinux
1848  * controls are not based on the Linux identity attributes, SELinux does not
1849  * need to control this operation.  However, SELinux does control the use of
1850  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1851  */
1852
1853 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1854                            int cap, int audit)
1855 {
1856         int rc;
1857
1858         rc = cap_capable(tsk, cred, cap, audit);
1859         if (rc)
1860                 return rc;
1861
1862         return task_has_capability(tsk, cred, cap, audit);
1863 }
1864
1865 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1866 {
1867         int buflen, rc;
1868         char *buffer, *path, *end;
1869
1870         rc = -ENOMEM;
1871         buffer = (char *)__get_free_page(GFP_KERNEL);
1872         if (!buffer)
1873                 goto out;
1874
1875         buflen = PAGE_SIZE;
1876         end = buffer+buflen;
1877         *--end = '\0';
1878         buflen--;
1879         path = end-1;
1880         *path = '/';
1881         while (table) {
1882                 const char *name = table->procname;
1883                 size_t namelen = strlen(name);
1884                 buflen -= namelen + 1;
1885                 if (buflen < 0)
1886                         goto out_free;
1887                 end -= namelen;
1888                 memcpy(end, name, namelen);
1889                 *--end = '/';
1890                 path = end;
1891                 table = table->parent;
1892         }
1893         buflen -= 4;
1894         if (buflen < 0)
1895                 goto out_free;
1896         end -= 4;
1897         memcpy(end, "/sys", 4);
1898         path = end;
1899         rc = security_genfs_sid("proc", path, tclass, sid);
1900 out_free:
1901         free_page((unsigned long)buffer);
1902 out:
1903         return rc;
1904 }
1905
1906 static int selinux_sysctl(ctl_table *table, int op)
1907 {
1908         int error = 0;
1909         u32 av;
1910         u32 tsid, sid;
1911         int rc;
1912
1913         sid = current_sid();
1914
1915         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1916                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1917         if (rc) {
1918                 /* Default to the well-defined sysctl SID. */
1919                 tsid = SECINITSID_SYSCTL;
1920         }
1921
1922         /* The op values are "defined" in sysctl.c, thereby creating
1923          * a bad coupling between this module and sysctl.c */
1924         if (op == 001) {
1925                 error = avc_has_perm(sid, tsid,
1926                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1927         } else {
1928                 av = 0;
1929                 if (op & 004)
1930                         av |= FILE__READ;
1931                 if (op & 002)
1932                         av |= FILE__WRITE;
1933                 if (av)
1934                         error = avc_has_perm(sid, tsid,
1935                                              SECCLASS_FILE, av, NULL);
1936         }
1937
1938         return error;
1939 }
1940
1941 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1942 {
1943         const struct cred *cred = current_cred();
1944         int rc = 0;
1945
1946         if (!sb)
1947                 return 0;
1948
1949         switch (cmds) {
1950         case Q_SYNC:
1951         case Q_QUOTAON:
1952         case Q_QUOTAOFF:
1953         case Q_SETINFO:
1954         case Q_SETQUOTA:
1955                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1956                 break;
1957         case Q_GETFMT:
1958         case Q_GETINFO:
1959         case Q_GETQUOTA:
1960                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1961                 break;
1962         default:
1963                 rc = 0;  /* let the kernel handle invalid cmds */
1964                 break;
1965         }
1966         return rc;
1967 }
1968
1969 static int selinux_quota_on(struct dentry *dentry)
1970 {
1971         const struct cred *cred = current_cred();
1972
1973         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1974 }
1975
1976 static int selinux_syslog(int type)
1977 {
1978         int rc;
1979
1980         switch (type) {
1981         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1982         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1983                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1984                 break;
1985         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1986         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1987         /* Set level of messages printed to console */
1988         case SYSLOG_ACTION_CONSOLE_LEVEL:
1989                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1990                 break;
1991         case SYSLOG_ACTION_CLOSE:       /* Close log */
1992         case SYSLOG_ACTION_OPEN:        /* Open log */
1993         case SYSLOG_ACTION_READ:        /* Read from log */
1994         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1995         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1996         default:
1997                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1998                 break;
1999         }
2000         return rc;
2001 }
2002
2003 /*
2004  * Check that a process has enough memory to allocate a new virtual
2005  * mapping. 0 means there is enough memory for the allocation to
2006  * succeed and -ENOMEM implies there is not.
2007  *
2008  * Do not audit the selinux permission check, as this is applied to all
2009  * processes that allocate mappings.
2010  */
2011 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2012 {
2013         int rc, cap_sys_admin = 0;
2014
2015         rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
2016                              SECURITY_CAP_NOAUDIT);
2017         if (rc == 0)
2018                 cap_sys_admin = 1;
2019
2020         return __vm_enough_memory(mm, pages, cap_sys_admin);
2021 }
2022
2023 /* binprm security operations */
2024
2025 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2026 {
2027         const struct task_security_struct *old_tsec;
2028         struct task_security_struct *new_tsec;
2029         struct inode_security_struct *isec;
2030         struct common_audit_data ad;
2031         struct inode *inode = bprm->file->f_path.dentry->d_inode;
2032         int rc;
2033
2034         rc = cap_bprm_set_creds(bprm);
2035         if (rc)
2036                 return rc;
2037
2038         /* SELinux context only depends on initial program or script and not
2039          * the script interpreter */
2040         if (bprm->cred_prepared)
2041                 return 0;
2042
2043         old_tsec = current_security();
2044         new_tsec = bprm->cred->security;
2045         isec = inode->i_security;
2046
2047         /* Default to the current task SID. */
2048         new_tsec->sid = old_tsec->sid;
2049         new_tsec->osid = old_tsec->sid;
2050
2051         /* Reset fs, key, and sock SIDs on execve. */
2052         new_tsec->create_sid = 0;
2053         new_tsec->keycreate_sid = 0;
2054         new_tsec->sockcreate_sid = 0;
2055
2056         if (old_tsec->exec_sid) {
2057                 new_tsec->sid = old_tsec->exec_sid;
2058                 /* Reset exec SID on execve. */
2059                 new_tsec->exec_sid = 0;
2060         } else {
2061                 /* Check for a default transition on this program. */
2062                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2063                                              SECCLASS_PROCESS, &new_tsec->sid);
2064                 if (rc)
2065                         return rc;
2066         }
2067
2068         COMMON_AUDIT_DATA_INIT(&ad, FS);
2069         ad.u.fs.path = bprm->file->f_path;
2070
2071         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2072                 new_tsec->sid = old_tsec->sid;
2073
2074         if (new_tsec->sid == old_tsec->sid) {
2075                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2076                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2077                 if (rc)
2078                         return rc;
2079         } else {
2080                 /* Check permissions for the transition. */
2081                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2082                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2083                 if (rc)
2084                         return rc;
2085
2086                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2087                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2088                 if (rc)
2089                         return rc;
2090
2091                 /* Check for shared state */
2092                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2093                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2094                                           SECCLASS_PROCESS, PROCESS__SHARE,
2095                                           NULL);
2096                         if (rc)
2097                                 return -EPERM;
2098                 }
2099
2100                 /* Make sure that anyone attempting to ptrace over a task that
2101                  * changes its SID has the appropriate permit */
2102                 if (bprm->unsafe &
2103                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2104                         struct task_struct *tracer;
2105                         struct task_security_struct *sec;
2106                         u32 ptsid = 0;
2107
2108                         rcu_read_lock();
2109                         tracer = tracehook_tracer_task(current);
2110                         if (likely(tracer != NULL)) {
2111                                 sec = __task_cred(tracer)->security;
2112                                 ptsid = sec->sid;
2113                         }
2114                         rcu_read_unlock();
2115
2116                         if (ptsid != 0) {
2117                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2118                                                   SECCLASS_PROCESS,
2119                                                   PROCESS__PTRACE, NULL);
2120                                 if (rc)
2121                                         return -EPERM;
2122                         }
2123                 }
2124
2125                 /* Clear any possibly unsafe personality bits on exec: */
2126                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2127         }
2128
2129         return 0;
2130 }
2131
2132 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2133 {
2134         const struct task_security_struct *tsec = current_security();
2135         u32 sid, osid;
2136         int atsecure = 0;
2137
2138         sid = tsec->sid;
2139         osid = tsec->osid;
2140
2141         if (osid != sid) {
2142                 /* Enable secure mode for SIDs transitions unless
2143                    the noatsecure permission is granted between
2144                    the two SIDs, i.e. ahp returns 0. */
2145                 atsecure = avc_has_perm(osid, sid,
2146                                         SECCLASS_PROCESS,
2147                                         PROCESS__NOATSECURE, NULL);
2148         }
2149
2150         return (atsecure || cap_bprm_secureexec(bprm));
2151 }
2152
2153 extern struct vfsmount *selinuxfs_mount;
2154 extern struct dentry *selinux_null;
2155
2156 /* Derived from fs/exec.c:flush_old_files. */
2157 static inline void flush_unauthorized_files(const struct cred *cred,
2158                                             struct files_struct *files)
2159 {
2160         struct common_audit_data ad;
2161         struct file *file, *devnull = NULL;
2162         struct tty_struct *tty;
2163         struct fdtable *fdt;
2164         long j = -1;
2165         int drop_tty = 0;
2166
2167         tty = get_current_tty();
2168         if (tty) {
2169                 spin_lock(&tty_files_lock);
2170                 if (!list_empty(&tty->tty_files)) {
2171                         struct tty_file_private *file_priv;
2172                         struct inode *inode;
2173
2174                         /* Revalidate access to controlling tty.
2175                            Use inode_has_perm on the tty inode directly rather
2176                            than using file_has_perm, as this particular open
2177                            file may belong to another process and we are only
2178                            interested in the inode-based check here. */
2179                         file_priv = list_first_entry(&tty->tty_files,
2180                                                 struct tty_file_private, list);
2181                         file = file_priv->file;
2182                         inode = file->f_path.dentry->d_inode;
2183                         if (inode_has_perm(cred, inode,
2184                                            FILE__READ | FILE__WRITE, NULL)) {
2185                                 drop_tty = 1;
2186                         }
2187                 }
2188                 spin_unlock(&tty_files_lock);
2189                 tty_kref_put(tty);
2190         }
2191         /* Reset controlling tty. */
2192         if (drop_tty)
2193                 no_tty();
2194
2195         /* Revalidate access to inherited open files. */
2196
2197         COMMON_AUDIT_DATA_INIT(&ad, FS);
2198
2199         spin_lock(&files->file_lock);
2200         for (;;) {
2201                 unsigned long set, i;
2202                 int fd;
2203
2204                 j++;
2205                 i = j * __NFDBITS;
2206                 fdt = files_fdtable(files);
2207                 if (i >= fdt->max_fds)
2208                         break;
2209                 set = fdt->open_fds->fds_bits[j];
2210                 if (!set)
2211                         continue;
2212                 spin_unlock(&files->file_lock);
2213                 for ( ; set ; i++, set >>= 1) {
2214                         if (set & 1) {
2215                                 file = fget(i);
2216                                 if (!file)
2217                                         continue;
2218                                 if (file_has_perm(cred,
2219                                                   file,
2220                                                   file_to_av(file))) {
2221                                         sys_close(i);
2222                                         fd = get_unused_fd();
2223                                         if (fd != i) {
2224                                                 if (fd >= 0)
2225                                                         put_unused_fd(fd);
2226                                                 fput(file);
2227                                                 continue;
2228                                         }
2229                                         if (devnull) {
2230                                                 get_file(devnull);
2231                                         } else {
2232                                                 devnull = dentry_open(
2233                                                         dget(selinux_null),
2234                                                         mntget(selinuxfs_mount),
2235                                                         O_RDWR, cred);
2236                                                 if (IS_ERR(devnull)) {
2237                                                         devnull = NULL;
2238                                                         put_unused_fd(fd);
2239                                                         fput(file);
2240                                                         continue;
2241                                                 }
2242                                         }
2243                                         fd_install(fd, devnull);
2244                                 }
2245                                 fput(file);
2246                         }
2247                 }
2248                 spin_lock(&files->file_lock);
2249
2250         }
2251         spin_unlock(&files->file_lock);
2252 }
2253
2254 /*
2255  * Prepare a process for imminent new credential changes due to exec
2256  */
2257 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2258 {
2259         struct task_security_struct *new_tsec;
2260         struct rlimit *rlim, *initrlim;
2261         int rc, i;
2262
2263         new_tsec = bprm->cred->security;
2264         if (new_tsec->sid == new_tsec->osid)
2265                 return;
2266
2267         /* Close files for which the new task SID is not authorized. */
2268         flush_unauthorized_files(bprm->cred, current->files);
2269
2270         /* Always clear parent death signal on SID transitions. */
2271         current->pdeath_signal = 0;
2272
2273         /* Check whether the new SID can inherit resource limits from the old
2274          * SID.  If not, reset all soft limits to the lower of the current
2275          * task's hard limit and the init task's soft limit.
2276          *
2277          * Note that the setting of hard limits (even to lower them) can be
2278          * controlled by the setrlimit check.  The inclusion of the init task's
2279          * soft limit into the computation is to avoid resetting soft limits
2280          * higher than the default soft limit for cases where the default is
2281          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2282          */
2283         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2284                           PROCESS__RLIMITINH, NULL);
2285         if (rc) {
2286                 /* protect against do_prlimit() */
2287                 task_lock(current);
2288                 for (i = 0; i < RLIM_NLIMITS; i++) {
2289                         rlim = current->signal->rlim + i;
2290                         initrlim = init_task.signal->rlim + i;
2291                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2292                 }
2293                 task_unlock(current);
2294                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2295         }
2296 }
2297
2298 /*
2299  * Clean up the process immediately after the installation of new credentials
2300  * due to exec
2301  */
2302 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2303 {
2304         const struct task_security_struct *tsec = current_security();
2305         struct itimerval itimer;
2306         u32 osid, sid;
2307         int rc, i;
2308
2309         osid = tsec->osid;
2310         sid = tsec->sid;
2311
2312         if (sid == osid)
2313                 return;
2314
2315         /* Check whether the new SID can inherit signal state from the old SID.
2316          * If not, clear itimers to avoid subsequent signal generation and
2317          * flush and unblock signals.
2318          *
2319          * This must occur _after_ the task SID has been updated so that any
2320          * kill done after the flush will be checked against the new SID.
2321          */
2322         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2323         if (rc) {
2324                 memset(&itimer, 0, sizeof itimer);
2325                 for (i = 0; i < 3; i++)
2326                         do_setitimer(i, &itimer, NULL);
2327                 spin_lock_irq(&current->sighand->siglock);
2328                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2329                         __flush_signals(current);
2330                         flush_signal_handlers(current, 1);
2331                         sigemptyset(&current->blocked);
2332                 }
2333                 spin_unlock_irq(&current->sighand->siglock);
2334         }
2335
2336         /* Wake up the parent if it is waiting so that it can recheck
2337          * wait permission to the new task SID. */
2338         read_lock(&tasklist_lock);
2339         __wake_up_parent(current, current->real_parent);
2340         read_unlock(&tasklist_lock);
2341 }
2342
2343 /* superblock security operations */
2344
2345 static int selinux_sb_alloc_security(struct super_block *sb)
2346 {
2347         return superblock_alloc_security(sb);
2348 }
2349
2350 static void selinux_sb_free_security(struct super_block *sb)
2351 {
2352         superblock_free_security(sb);
2353 }
2354
2355 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2356 {
2357         if (plen > olen)
2358                 return 0;
2359
2360         return !memcmp(prefix, option, plen);
2361 }
2362
2363 static inline int selinux_option(char *option, int len)
2364 {
2365         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2366                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2367                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2368                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2369                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2370 }
2371
2372 static inline void take_option(char **to, char *from, int *first, int len)
2373 {
2374         if (!*first) {
2375                 **to = ',';
2376                 *to += 1;
2377         } else
2378                 *first = 0;
2379         memcpy(*to, from, len);
2380         *to += len;
2381 }
2382
2383 static inline void take_selinux_option(char **to, char *from, int *first,
2384                                        int len)
2385 {
2386         int current_size = 0;
2387
2388         if (!*first) {
2389                 **to = '|';
2390                 *to += 1;
2391         } else
2392                 *first = 0;
2393
2394         while (current_size < len) {
2395                 if (*from != '"') {
2396                         **to = *from;
2397                         *to += 1;
2398                 }
2399                 from += 1;
2400                 current_size += 1;
2401         }
2402 }
2403
2404 static int selinux_sb_copy_data(char *orig, char *copy)
2405 {
2406         int fnosec, fsec, rc = 0;
2407         char *in_save, *in_curr, *in_end;
2408         char *sec_curr, *nosec_save, *nosec;
2409         int open_quote = 0;
2410
2411         in_curr = orig;
2412         sec_curr = copy;
2413
2414         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2415         if (!nosec) {
2416                 rc = -ENOMEM;
2417                 goto out;
2418         }
2419
2420         nosec_save = nosec;
2421         fnosec = fsec = 1;
2422         in_save = in_end = orig;
2423
2424         do {
2425                 if (*in_end == '"')
2426                         open_quote = !open_quote;
2427                 if ((*in_end == ',' && open_quote == 0) ||
2428                                 *in_end == '\0') {
2429                         int len = in_end - in_curr;
2430
2431                         if (selinux_option(in_curr, len))
2432                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2433                         else
2434                                 take_option(&nosec, in_curr, &fnosec, len);
2435
2436                         in_curr = in_end + 1;
2437                 }
2438         } while (*in_end++);
2439
2440         strcpy(in_save, nosec_save);
2441         free_page((unsigned long)nosec_save);
2442 out:
2443         return rc;
2444 }
2445
2446 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2447 {
2448         const struct cred *cred = current_cred();
2449         struct common_audit_data ad;
2450         int rc;
2451
2452         rc = superblock_doinit(sb, data);
2453         if (rc)
2454                 return rc;
2455
2456         /* Allow all mounts performed by the kernel */
2457         if (flags & MS_KERNMOUNT)
2458                 return 0;
2459
2460         COMMON_AUDIT_DATA_INIT(&ad, FS);
2461         ad.u.fs.path.dentry = sb->s_root;
2462         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2463 }
2464
2465 static int selinux_sb_statfs(struct dentry *dentry)
2466 {
2467         const struct cred *cred = current_cred();
2468         struct common_audit_data ad;
2469
2470         COMMON_AUDIT_DATA_INIT(&ad, FS);
2471         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2472         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2473 }
2474
2475 static int selinux_mount(char *dev_name,
2476                          struct path *path,
2477                          char *type,
2478                          unsigned long flags,
2479                          void *data)
2480 {
2481         const struct cred *cred = current_cred();
2482
2483         if (flags & MS_REMOUNT)
2484                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2485                                            FILESYSTEM__REMOUNT, NULL);
2486         else
2487                 return dentry_has_perm(cred, path->mnt, path->dentry,
2488                                        FILE__MOUNTON);
2489 }
2490
2491 static int selinux_umount(struct vfsmount *mnt, int flags)
2492 {
2493         const struct cred *cred = current_cred();
2494
2495         return superblock_has_perm(cred, mnt->mnt_sb,
2496                                    FILESYSTEM__UNMOUNT, NULL);
2497 }
2498
2499 /* inode security operations */
2500
2501 static int selinux_inode_alloc_security(struct inode *inode)
2502 {
2503         return inode_alloc_security(inode);
2504 }
2505
2506 static void selinux_inode_free_security(struct inode *inode)
2507 {
2508         inode_free_security(inode);
2509 }
2510
2511 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2512                                        char **name, void **value,
2513                                        size_t *len)
2514 {
2515         const struct task_security_struct *tsec = current_security();
2516         struct inode_security_struct *dsec;
2517         struct superblock_security_struct *sbsec;
2518         u32 sid, newsid, clen;
2519         int rc;
2520         char *namep = NULL, *context;
2521
2522         dsec = dir->i_security;
2523         sbsec = dir->i_sb->s_security;
2524
2525         sid = tsec->sid;
2526         newsid = tsec->create_sid;
2527
2528         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2529                 rc = security_transition_sid(sid, dsec->sid,
2530                                              inode_mode_to_security_class(inode->i_mode),
2531                                              &newsid);
2532                 if (rc) {
2533                         printk(KERN_WARNING "%s:  "
2534                                "security_transition_sid failed, rc=%d (dev=%s "
2535                                "ino=%ld)\n",
2536                                __func__,
2537                                -rc, inode->i_sb->s_id, inode->i_ino);
2538                         return rc;
2539                 }
2540         }
2541
2542         /* Possibly defer initialization to selinux_complete_init. */
2543         if (sbsec->flags & SE_SBINITIALIZED) {
2544                 struct inode_security_struct *isec = inode->i_security;
2545                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2546                 isec->sid = newsid;
2547                 isec->initialized = 1;
2548         }
2549
2550         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2551                 return -EOPNOTSUPP;
2552
2553         if (name) {
2554                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2555                 if (!namep)
2556                         return -ENOMEM;
2557                 *name = namep;
2558         }
2559
2560         if (value && len) {
2561                 rc = security_sid_to_context_force(newsid, &context, &clen);
2562                 if (rc) {
2563                         kfree(namep);
2564                         return rc;
2565                 }
2566                 *value = context;
2567                 *len = clen;
2568         }
2569
2570         return 0;
2571 }
2572
2573 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2574 {
2575         return may_create(dir, dentry, SECCLASS_FILE);
2576 }
2577
2578 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2579 {
2580         return may_link(dir, old_dentry, MAY_LINK);
2581 }
2582
2583 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2584 {
2585         return may_link(dir, dentry, MAY_UNLINK);
2586 }
2587
2588 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2589 {
2590         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2591 }
2592
2593 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2594 {
2595         return may_create(dir, dentry, SECCLASS_DIR);
2596 }
2597
2598 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2599 {
2600         return may_link(dir, dentry, MAY_RMDIR);
2601 }
2602
2603 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2604 {
2605         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2606 }
2607
2608 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2609                                 struct inode *new_inode, struct dentry *new_dentry)
2610 {
2611         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2612 }
2613
2614 static int selinux_inode_readlink(struct dentry *dentry)
2615 {
2616         const struct cred *cred = current_cred();
2617
2618         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2619 }
2620
2621 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2622 {
2623         const struct cred *cred = current_cred();
2624
2625         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2626 }
2627
2628 static int selinux_inode_permission(struct inode *inode, int mask)
2629 {
2630         const struct cred *cred = current_cred();
2631         struct common_audit_data ad;
2632         u32 perms;
2633         bool from_access;
2634
2635         from_access = mask & MAY_ACCESS;
2636         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2637
2638         /* No permission to check.  Existence test. */
2639         if (!mask)
2640                 return 0;
2641
2642         COMMON_AUDIT_DATA_INIT(&ad, FS);
2643         ad.u.fs.inode = inode;
2644
2645         if (from_access)
2646                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2647
2648         perms = file_mask_to_av(inode->i_mode, mask);
2649
2650         return inode_has_perm(cred, inode, perms, &ad);
2651 }
2652
2653 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2654 {
2655         const struct cred *cred = current_cred();
2656         unsigned int ia_valid = iattr->ia_valid;
2657
2658         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2659         if (ia_valid & ATTR_FORCE) {
2660                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2661                               ATTR_FORCE);
2662                 if (!ia_valid)
2663                         return 0;
2664         }
2665
2666         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2667                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2668                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2669
2670         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2671 }
2672
2673 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2674 {
2675         const struct cred *cred = current_cred();
2676
2677         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2678 }
2679
2680 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2681 {
2682         const struct cred *cred = current_cred();
2683
2684         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2685                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2686                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2687                         if (!capable(CAP_SETFCAP))
2688                                 return -EPERM;
2689                 } else if (!capable(CAP_SYS_ADMIN)) {
2690                         /* A different attribute in the security namespace.
2691                            Restrict to administrator. */
2692                         return -EPERM;
2693                 }
2694         }
2695
2696         /* Not an attribute we recognize, so just check the
2697            ordinary setattr permission. */
2698         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2699 }
2700
2701 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2702                                   const void *value, size_t size, int flags)
2703 {
2704         struct inode *inode = dentry->d_inode;
2705         struct inode_security_struct *isec = inode->i_security;
2706         struct superblock_security_struct *sbsec;
2707         struct common_audit_data ad;
2708         u32 newsid, sid = current_sid();
2709         int rc = 0;
2710
2711         if (strcmp(name, XATTR_NAME_SELINUX))
2712                 return selinux_inode_setotherxattr(dentry, name);
2713
2714         sbsec = inode->i_sb->s_security;
2715         if (!(sbsec->flags & SE_SBLABELSUPP))
2716                 return -EOPNOTSUPP;
2717
2718         if (!is_owner_or_cap(inode))
2719                 return -EPERM;
2720
2721         COMMON_AUDIT_DATA_INIT(&ad, FS);
2722         ad.u.fs.path.dentry = dentry;
2723
2724         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2725                           FILE__RELABELFROM, &ad);
2726         if (rc)
2727                 return rc;
2728
2729         rc = security_context_to_sid(value, size, &newsid);
2730         if (rc == -EINVAL) {
2731                 if (!capable(CAP_MAC_ADMIN))
2732                         return rc;
2733                 rc = security_context_to_sid_force(value, size, &newsid);
2734         }
2735         if (rc)
2736                 return rc;
2737
2738         rc = avc_has_perm(sid, newsid, isec->sclass,
2739                           FILE__RELABELTO, &ad);
2740         if (rc)
2741                 return rc;
2742
2743         rc = security_validate_transition(isec->sid, newsid, sid,
2744                                           isec->sclass);
2745         if (rc)
2746                 return rc;
2747
2748         return avc_has_perm(newsid,
2749                             sbsec->sid,
2750                             SECCLASS_FILESYSTEM,
2751                             FILESYSTEM__ASSOCIATE,
2752                             &ad);
2753 }
2754
2755 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2756                                         const void *value, size_t size,
2757                                         int flags)
2758 {
2759         struct inode *inode = dentry->d_inode;
2760         struct inode_security_struct *isec = inode->i_security;
2761         u32 newsid;
2762         int rc;
2763
2764         if (strcmp(name, XATTR_NAME_SELINUX)) {
2765                 /* Not an attribute we recognize, so nothing to do. */
2766                 return;
2767         }
2768
2769         rc = security_context_to_sid_force(value, size, &newsid);
2770         if (rc) {
2771                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2772                        "for (%s, %lu), rc=%d\n",
2773                        inode->i_sb->s_id, inode->i_ino, -rc);
2774                 return;
2775         }
2776
2777         isec->sid = newsid;
2778         return;
2779 }
2780
2781 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2782 {
2783         const struct cred *cred = current_cred();
2784
2785         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2786 }
2787
2788 static int selinux_inode_listxattr(struct dentry *dentry)
2789 {
2790         const struct cred *cred = current_cred();
2791
2792         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2793 }
2794
2795 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2796 {
2797         if (strcmp(name, XATTR_NAME_SELINUX))
2798                 return selinux_inode_setotherxattr(dentry, name);
2799
2800         /* No one is allowed to remove a SELinux security label.
2801            You can change the label, but all data must be labeled. */
2802         return -EACCES;
2803 }
2804
2805 /*
2806  * Copy the inode security context value to the user.
2807  *
2808  * Permission check is handled by selinux_inode_getxattr hook.
2809  */
2810 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2811 {
2812         u32 size;
2813         int error;
2814         char *context = NULL;
2815         struct inode_security_struct *isec = inode->i_security;
2816
2817         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2818                 return -EOPNOTSUPP;
2819
2820         /*
2821          * If the caller has CAP_MAC_ADMIN, then get the raw context
2822          * value even if it is not defined by current policy; otherwise,
2823          * use the in-core value under current policy.
2824          * Use the non-auditing forms of the permission checks since
2825          * getxattr may be called by unprivileged processes commonly
2826          * and lack of permission just means that we fall back to the
2827          * in-core context value, not a denial.
2828          */
2829         error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
2830                                 SECURITY_CAP_NOAUDIT);
2831         if (!error)
2832                 error = security_sid_to_context_force(isec->sid, &context,
2833                                                       &size);
2834         else
2835                 error = security_sid_to_context(isec->sid, &context, &size);
2836         if (error)
2837                 return error;
2838         error = size;
2839         if (alloc) {
2840                 *buffer = context;
2841                 goto out_nofree;
2842         }
2843         kfree(context);
2844 out_nofree:
2845         return error;
2846 }
2847
2848 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2849                                      const void *value, size_t size, int flags)
2850 {
2851         struct inode_security_struct *isec = inode->i_security;
2852         u32 newsid;
2853         int rc;
2854
2855         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2856                 return -EOPNOTSUPP;
2857
2858         if (!value || !size)
2859                 return -EACCES;
2860
2861         rc = security_context_to_sid((void *)value, size, &newsid);
2862         if (rc)
2863                 return rc;
2864
2865         isec->sid = newsid;
2866         isec->initialized = 1;
2867         return 0;
2868 }
2869
2870 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2871 {
2872         const int len = sizeof(XATTR_NAME_SELINUX);
2873         if (buffer && len <= buffer_size)
2874                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2875         return len;
2876 }
2877
2878 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2879 {
2880         struct inode_security_struct *isec = inode->i_security;
2881         *secid = isec->sid;
2882 }
2883
2884 /* file security operations */
2885
2886 static int selinux_revalidate_file_permission(struct file *file, int mask)
2887 {
2888         const struct cred *cred = current_cred();
2889         struct inode *inode = file->f_path.dentry->d_inode;
2890
2891         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2892         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2893                 mask |= MAY_APPEND;
2894
2895         return file_has_perm(cred, file,
2896                              file_mask_to_av(inode->i_mode, mask));
2897 }
2898
2899 static int selinux_file_permission(struct file *file, int mask)
2900 {
2901         struct inode *inode = file->f_path.dentry->d_inode;
2902         struct file_security_struct *fsec = file->f_security;
2903         struct inode_security_struct *isec = inode->i_security;
2904         u32 sid = current_sid();
2905
2906         if (!mask)
2907                 /* No permission to check.  Existence test. */
2908                 return 0;
2909
2910         if (sid == fsec->sid && fsec->isid == isec->sid &&
2911             fsec->pseqno == avc_policy_seqno())
2912                 /* No change since dentry_open check. */
2913                 return 0;
2914
2915         return selinux_revalidate_file_permission(file, mask);
2916 }
2917
2918 static int selinux_file_alloc_security(struct file *file)
2919 {
2920         return file_alloc_security(file);
2921 }
2922
2923 static void selinux_file_free_security(struct file *file)
2924 {
2925         file_free_security(file);
2926 }
2927
2928 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2929                               unsigned long arg)
2930 {
2931         const struct cred *cred = current_cred();
2932         u32 av = 0;
2933
2934         if (_IOC_DIR(cmd) & _IOC_WRITE)
2935                 av |= FILE__WRITE;
2936         if (_IOC_DIR(cmd) & _IOC_READ)
2937                 av |= FILE__READ;
2938         if (!av)
2939                 av = FILE__IOCTL;
2940
2941         return file_has_perm(cred, file, av);
2942 }
2943
2944 static int default_noexec;
2945
2946 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2947 {
2948         const struct cred *cred = current_cred();
2949         int rc = 0;
2950
2951         if (default_noexec &&
2952             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2953                 /*
2954                  * We are making executable an anonymous mapping or a
2955                  * private file mapping that will also be writable.
2956                  * This has an additional check.
2957                  */
2958                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
2959                 if (rc)
2960                         goto error;
2961         }
2962
2963         if (file) {
2964                 /* read access is always possible with a mapping */
2965                 u32 av = FILE__READ;
2966
2967                 /* write access only matters if the mapping is shared */
2968                 if (shared && (prot & PROT_WRITE))
2969                         av |= FILE__WRITE;
2970
2971                 if (prot & PROT_EXEC)
2972                         av |= FILE__EXECUTE;
2973
2974                 return file_has_perm(cred, file, av);
2975         }
2976
2977 error:
2978         return rc;
2979 }
2980
2981 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2982                              unsigned long prot, unsigned long flags,
2983                              unsigned long addr, unsigned long addr_only)
2984 {
2985         int rc = 0;
2986         u32 sid = current_sid();
2987
2988         /*
2989          * notice that we are intentionally putting the SELinux check before
2990          * the secondary cap_file_mmap check.  This is such a likely attempt
2991          * at bad behaviour/exploit that we always want to get the AVC, even
2992          * if DAC would have also denied the operation.
2993          */
2994         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
2995                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2996                                   MEMPROTECT__MMAP_ZERO, NULL);
2997                 if (rc)
2998                         return rc;
2999         }
3000
3001         /* do DAC check on address space usage */
3002         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3003         if (rc || addr_only)
3004                 return rc;
3005
3006         if (selinux_checkreqprot)
3007                 prot = reqprot;
3008
3009         return file_map_prot_check(file, prot,
3010                                    (flags & MAP_TYPE) == MAP_SHARED);
3011 }
3012
3013 static int selinux_file_mprotect(struct vm_area_struct *vma,
3014                                  unsigned long reqprot,
3015                                  unsigned long prot)
3016 {
3017         const struct cred *cred = current_cred();
3018
3019         if (selinux_checkreqprot)
3020                 prot = reqprot;
3021
3022         if (default_noexec &&
3023             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3024                 int rc = 0;
3025                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3026                     vma->vm_end <= vma->vm_mm->brk) {
3027                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3028                 } else if (!vma->vm_file &&
3029                            vma->vm_start <= vma->vm_mm->start_stack &&
3030                            vma->vm_end >= vma->vm_mm->start_stack) {
3031                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3032                 } else if (vma->vm_file && vma->anon_vma) {
3033                         /*
3034                          * We are making executable a file mapping that has
3035                          * had some COW done. Since pages might have been
3036                          * written, check ability to execute the possibly
3037                          * modified content.  This typically should only
3038                          * occur for text relocations.
3039                          */
3040                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3041                 }
3042                 if (rc)
3043                         return rc;
3044         }
3045
3046         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3047 }
3048
3049 static int selinux_file_lock(struct file *file, unsigned int cmd)
3050 {
3051         const struct cred *cred = current_cred();
3052
3053         return file_has_perm(cred, file, FILE__LOCK);
3054 }
3055
3056 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3057                               unsigned long arg)
3058 {
3059         const struct cred *cred = current_cred();
3060         int err = 0;
3061
3062         switch (cmd) {
3063         case F_SETFL:
3064                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3065                         err = -EINVAL;
3066                         break;
3067                 }
3068
3069                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3070                         err = file_has_perm(cred, file, FILE__WRITE);
3071                         break;
3072                 }
3073                 /* fall through */
3074         case F_SETOWN:
3075         case F_SETSIG:
3076         case F_GETFL:
3077         case F_GETOWN:
3078         case F_GETSIG:
3079                 /* Just check FD__USE permission */
3080                 err = file_has_perm(cred, file, 0);
3081                 break;
3082         case F_GETLK:
3083         case F_SETLK:
3084         case F_SETLKW:
3085 #if BITS_PER_LONG == 32
3086         case F_GETLK64:
3087         case F_SETLK64:
3088         case F_SETLKW64:
3089 #endif
3090                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3091                         err = -EINVAL;
3092                         break;
3093                 }
3094                 err = file_has_perm(cred, file, FILE__LOCK);
3095                 break;
3096         }
3097
3098         return err;
3099 }
3100
3101 static int selinux_file_set_fowner(struct file *file)
3102 {
3103         struct file_security_struct *fsec;
3104
3105         fsec = file->f_security;
3106         fsec->fown_sid = current_sid();
3107
3108         return 0;
3109 }
3110
3111 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3112                                        struct fown_struct *fown, int signum)
3113 {
3114         struct file *file;
3115         u32 sid = task_sid(tsk);
3116         u32 perm;
3117         struct file_security_struct *fsec;
3118
3119         /* struct fown_struct is never outside the context of a struct file */
3120         file = container_of(fown, struct file, f_owner);
3121
3122         fsec = file->f_security;
3123
3124         if (!signum)
3125                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3126         else
3127                 perm = signal_to_av(signum);
3128
3129         return avc_has_perm(fsec->fown_sid, sid,
3130                             SECCLASS_PROCESS, perm, NULL);
3131 }
3132
3133 static int selinux_file_receive(struct file *file)
3134 {
3135         const struct cred *cred = current_cred();
3136
3137         return file_has_perm(cred, file, file_to_av(file));
3138 }
3139
3140 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3141 {
3142         struct file_security_struct *fsec;
3143         struct inode *inode;
3144         struct inode_security_struct *isec;
3145
3146         inode = file->f_path.dentry->d_inode;
3147         fsec = file->f_security;
3148         isec = inode->i_security;
3149         /*
3150          * Save inode label and policy sequence number
3151          * at open-time so that selinux_file_permission
3152          * can determine whether revalidation is necessary.
3153          * Task label is already saved in the file security
3154          * struct as its SID.
3155          */
3156         fsec->isid = isec->sid;
3157         fsec->pseqno = avc_policy_seqno();
3158         /*
3159          * Since the inode label or policy seqno may have changed
3160          * between the selinux_inode_permission check and the saving
3161          * of state above, recheck that access is still permitted.
3162          * Otherwise, access might never be revalidated against the
3163          * new inode label or new policy.
3164          * This check is not redundant - do not remove.
3165          */
3166         return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3167 }
3168
3169 /* task security operations */
3170
3171 static int selinux_task_create(unsigned long clone_flags)
3172 {
3173         return current_has_perm(current, PROCESS__FORK);
3174 }
3175
3176 /*
3177  * allocate the SELinux part of blank credentials
3178  */
3179 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3180 {
3181         struct task_security_struct *tsec;
3182
3183         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3184         if (!tsec)
3185                 return -ENOMEM;
3186
3187         cred->security = tsec;
3188         return 0;
3189 }
3190
3191 /*
3192  * detach and free the LSM part of a set of credentials
3193  */
3194 static void selinux_cred_free(struct cred *cred)
3195 {
3196         struct task_security_struct *tsec = cred->security;
3197
3198         BUG_ON((unsigned long) cred->security < PAGE_SIZE);
3199         cred->security = (void *) 0x7UL;
3200         kfree(tsec);
3201 }
3202
3203 /*
3204  * prepare a new set of credentials for modification
3205  */
3206 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3207                                 gfp_t gfp)
3208 {
3209         const struct task_security_struct *old_tsec;
3210         struct task_security_struct *tsec;
3211
3212         old_tsec = old->security;
3213
3214         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3215         if (!tsec)
3216                 return -ENOMEM;
3217
3218         new->security = tsec;
3219         return 0;
3220 }
3221
3222 /*
3223  * transfer the SELinux data to a blank set of creds
3224  */
3225 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3226 {
3227         const struct task_security_struct *old_tsec = old->security;
3228         struct task_security_struct *tsec = new->security;
3229
3230         *tsec = *old_tsec;
3231 }
3232
3233 /*
3234  * set the security data for a kernel service
3235  * - all the creation contexts are set to unlabelled
3236  */
3237 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3238 {
3239         struct task_security_struct *tsec = new->security;
3240         u32 sid = current_sid();
3241         int ret;
3242
3243         ret = avc_has_perm(sid, secid,
3244                            SECCLASS_KERNEL_SERVICE,
3245                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3246                            NULL);
3247         if (ret == 0) {
3248                 tsec->sid = secid;
3249                 tsec->create_sid = 0;
3250                 tsec->keycreate_sid = 0;
3251                 tsec->sockcreate_sid = 0;
3252         }
3253         return ret;
3254 }
3255
3256 /*
3257  * set the file creation context in a security record to the same as the
3258  * objective context of the specified inode
3259  */
3260 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3261 {
3262         struct inode_security_struct *isec = inode->i_security;
3263         struct task_security_struct *tsec = new->security;
3264         u32 sid = current_sid();
3265         int ret;
3266
3267         ret = avc_has_perm(sid, isec->sid,
3268                            SECCLASS_KERNEL_SERVICE,
3269                            KERNEL_SERVICE__CREATE_FILES_AS,
3270                            NULL);
3271
3272         if (ret == 0)
3273                 tsec->create_sid = isec->sid;
3274         return ret;
3275 }
3276
3277 static int selinux_kernel_module_request(char *kmod_name)
3278 {
3279         u32 sid;
3280         struct common_audit_data ad;
3281
3282         sid = task_sid(current);
3283
3284         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3285         ad.u.kmod_name = kmod_name;
3286
3287         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3288                             SYSTEM__MODULE_REQUEST, &ad);
3289 }
3290
3291 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3292 {
3293         return current_has_perm(p, PROCESS__SETPGID);
3294 }
3295
3296 static int selinux_task_getpgid(struct task_struct *p)
3297 {
3298         return current_has_perm(p, PROCESS__GETPGID);
3299 }
3300
3301 static int selinux_task_getsid(struct task_struct *p)
3302 {
3303         return current_has_perm(p, PROCESS__GETSESSION);
3304 }
3305
3306 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3307 {
3308         *secid = task_sid(p);
3309 }
3310
3311 static int selinux_task_setnice(struct task_struct *p, int nice)
3312 {
3313         int rc;
3314
3315         rc = cap_task_setnice(p, nice);
3316         if (rc)
3317                 return rc;
3318
3319         return current_has_perm(p, PROCESS__SETSCHED);
3320 }
3321
3322 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3323 {
3324         int rc;
3325
3326         rc = cap_task_setioprio(p, ioprio);
3327         if (rc)
3328                 return rc;
3329
3330         return current_has_perm(p, PROCESS__SETSCHED);
3331 }
3332
3333 static int selinux_task_getioprio(struct task_struct *p)
3334 {
3335         return current_has_perm(p, PROCESS__GETSCHED);
3336 }
3337
3338 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3339                 struct rlimit *new_rlim)
3340 {
3341         struct rlimit *old_rlim = p->signal->rlim + resource;
3342
3343         /* Control the ability to change the hard limit (whether
3344            lowering or raising it), so that the hard limit can
3345            later be used as a safe reset point for the soft limit
3346            upon context transitions.  See selinux_bprm_committing_creds. */
3347         if (old_rlim->rlim_max != new_rlim->rlim_max)
3348                 return current_has_perm(p, PROCESS__SETRLIMIT);
3349
3350         return 0;
3351 }
3352
3353 static int selinux_task_setscheduler(struct task_struct *p)
3354 {
3355         int rc;
3356
3357         rc = cap_task_setscheduler(p);
3358         if (rc)
3359                 return rc;
3360
3361         return current_has_perm(p, PROCESS__SETSCHED);
3362 }
3363
3364 static int selinux_task_getscheduler(struct task_struct *p)
3365 {
3366         return current_has_perm(p, PROCESS__GETSCHED);
3367 }
3368
3369 static int selinux_task_movememory(struct task_struct *p)
3370 {
3371         return current_has_perm(p, PROCESS__SETSCHED);
3372 }
3373
3374 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3375                                 int sig, u32 secid)
3376 {
3377         u32 perm;
3378         int rc;
3379
3380         if (!sig)
3381                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3382         else
3383                 perm = signal_to_av(sig);
3384         if (secid)
3385                 rc = avc_has_perm(secid, task_sid(p),
3386                                   SECCLASS_PROCESS, perm, NULL);
3387         else
3388                 rc = current_has_perm(p, perm);
3389         return rc;
3390 }
3391
3392 static int selinux_task_wait(struct task_struct *p)
3393 {
3394         return task_has_perm(p, current, PROCESS__SIGCHLD);
3395 }
3396
3397 static void selinux_task_to_inode(struct task_struct *p,
3398                                   struct inode *inode)
3399 {
3400         struct inode_security_struct *isec = inode->i_security;
3401         u32 sid = task_sid(p);
3402
3403         isec->sid = sid;
3404         isec->initialized = 1;
3405 }
3406
3407 /* Returns error only if unable to parse addresses */
3408 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3409                         struct common_audit_data *ad, u8 *proto)
3410 {
3411         int offset, ihlen, ret = -EINVAL;
3412         struct iphdr _iph, *ih;
3413
3414         offset = skb_network_offset(skb);
3415         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3416         if (ih == NULL)
3417                 goto out;
3418
3419         ihlen = ih->ihl * 4;
3420         if (ihlen < sizeof(_iph))
3421                 goto out;
3422
3423         ad->u.net.v4info.saddr = ih->saddr;
3424         ad->u.net.v4info.daddr = ih->daddr;
3425         ret = 0;
3426
3427         if (proto)
3428                 *proto = ih->protocol;
3429
3430         switch (ih->protocol) {
3431         case IPPROTO_TCP: {
3432                 struct tcphdr _tcph, *th;
3433
3434                 if (ntohs(ih->frag_off) & IP_OFFSET)
3435                         break;
3436
3437                 offset += ihlen;
3438                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3439                 if (th == NULL)
3440                         break;
3441
3442                 ad->u.net.sport = th->source;
3443                 ad->u.net.dport = th->dest;
3444                 break;
3445         }
3446
3447         case IPPROTO_UDP: {
3448                 struct udphdr _udph, *uh;
3449
3450                 if (ntohs(ih->frag_off) & IP_OFFSET)
3451                         break;
3452
3453                 offset += ihlen;
3454                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3455                 if (uh == NULL)
3456                         break;
3457
3458                 ad->u.net.sport = uh->source;
3459                 ad->u.net.dport = uh->dest;
3460                 break;
3461         }
3462
3463         case IPPROTO_DCCP: {
3464                 struct dccp_hdr _dccph, *dh;
3465
3466                 if (ntohs(ih->frag_off) & IP_OFFSET)
3467                         break;
3468
3469                 offset += ihlen;
3470                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3471                 if (dh == NULL)
3472                         break;
3473
3474                 ad->u.net.sport = dh->dccph_sport;
3475                 ad->u.net.dport = dh->dccph_dport;
3476                 break;
3477         }
3478
3479         default:
3480                 break;
3481         }
3482 out:
3483         return ret;
3484 }
3485
3486 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3487
3488 /* Returns error only if unable to parse addresses */
3489 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3490                         struct common_audit_data *ad, u8 *proto)
3491 {
3492         u8 nexthdr;
3493         int ret = -EINVAL, offset;
3494         struct ipv6hdr _ipv6h, *ip6;
3495
3496         offset = skb_network_offset(skb);
3497         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3498         if (ip6 == NULL)
3499                 goto out;
3500
3501         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3502         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3503         ret = 0;
3504
3505         nexthdr = ip6->nexthdr;
3506         offset += sizeof(_ipv6h);
3507         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3508         if (offset < 0)
3509                 goto out;
3510
3511         if (proto)
3512                 *proto = nexthdr;
3513
3514         switch (nexthdr) {
3515         case IPPROTO_TCP: {
3516                 struct tcphdr _tcph, *th;
3517
3518                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3519                 if (th == NULL)
3520                         break;
3521
3522                 ad->u.net.sport = th->source;
3523                 ad->u.net.dport = th->dest;
3524                 break;
3525         }
3526
3527         case IPPROTO_UDP: {
3528                 struct udphdr _udph, *uh;
3529
3530                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3531                 if (uh == NULL)
3532                         break;
3533
3534                 ad->u.net.sport = uh->source;
3535                 ad->u.net.dport = uh->dest;
3536                 break;
3537         }
3538
3539         case IPPROTO_DCCP: {
3540                 struct dccp_hdr _dccph, *dh;
3541
3542                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3543                 if (dh == NULL)
3544                         break;
3545
3546                 ad->u.net.sport = dh->dccph_sport;
3547                 ad->u.net.dport = dh->dccph_dport;
3548                 break;
3549         }
3550
3551         /* includes fragments */
3552         default:
3553                 break;
3554         }
3555 out:
3556         return ret;
3557 }
3558
3559 #endif /* IPV6 */
3560
3561 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3562                              char **_addrp, int src, u8 *proto)
3563 {
3564         char *addrp;
3565         int ret;
3566
3567         switch (ad->u.net.family) {
3568         case PF_INET:
3569                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3570                 if (ret)
3571                         goto parse_error;
3572                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3573                                        &ad->u.net.v4info.daddr);
3574                 goto okay;
3575
3576 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3577         case PF_INET6:
3578                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3579                 if (ret)
3580                         goto parse_error;
3581                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3582                                        &ad->u.net.v6info.daddr);
3583                 goto okay;
3584 #endif  /* IPV6 */
3585         default:
3586                 addrp = NULL;
3587                 goto okay;
3588         }
3589
3590 parse_error:
3591         printk(KERN_WARNING
3592                "SELinux: failure in selinux_parse_skb(),"
3593                " unable to parse packet\n");
3594         return ret;
3595
3596 okay:
3597         if (_addrp)
3598                 *_addrp = addrp;
3599         return 0;
3600 }
3601
3602 /**
3603  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3604  * @skb: the packet
3605  * @family: protocol family
3606  * @sid: the packet's peer label SID
3607  *
3608  * Description:
3609  * Check the various different forms of network peer labeling and determine
3610  * the peer label/SID for the packet; most of the magic actually occurs in
3611  * the security server function security_net_peersid_cmp().  The function
3612  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3613  * or -EACCES if @sid is invalid due to inconsistencies with the different
3614  * peer labels.
3615  *
3616  */
3617 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3618 {
3619         int err;
3620         u32 xfrm_sid;
3621         u32 nlbl_sid;
3622         u32 nlbl_type;
3623
3624         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3625         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3626
3627         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3628         if (unlikely(err)) {
3629                 printk(KERN_WARNING
3630                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3631                        " unable to determine packet's peer label\n");
3632                 return -EACCES;
3633         }
3634
3635         return 0;
3636 }
3637
3638 /* socket security operations */
3639
3640 static u32 socket_sockcreate_sid(const struct task_security_struct *tsec)
3641 {
3642         return tsec->sockcreate_sid ? : tsec->sid;
3643 }
3644
3645 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3646 {
3647         struct sk_security_struct *sksec = sk->sk_security;
3648         struct common_audit_data ad;
3649         u32 tsid = task_sid(task);
3650
3651         if (sksec->sid == SECINITSID_KERNEL)
3652                 return 0;
3653
3654         COMMON_AUDIT_DATA_INIT(&ad, NET);
3655         ad.u.net.sk = sk;
3656
3657         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3658 }
3659
3660 static int selinux_socket_create(int family, int type,
3661                                  int protocol, int kern)
3662 {
3663         const struct task_security_struct *tsec = current_security();
3664         u32 newsid;
3665         u16 secclass;
3666
3667         if (kern)
3668                 return 0;
3669
3670         newsid = socket_sockcreate_sid(tsec);
3671         secclass = socket_type_to_security_class(family, type, protocol);
3672         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3673 }
3674
3675 static int selinux_socket_post_create(struct socket *sock, int family,
3676                                       int type, int protocol, int kern)
3677 {
3678         const struct task_security_struct *tsec = current_security();
3679         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3680         struct sk_security_struct *sksec;
3681         int err = 0;
3682
3683         if (kern)
3684                 isec->sid = SECINITSID_KERNEL;
3685         else
3686                 isec->sid = socket_sockcreate_sid(tsec);
3687
3688         isec->sclass = socket_type_to_security_class(family, type, protocol);
3689         isec->initialized = 1;
3690
3691         if (sock->sk) {
3692                 sksec = sock->sk->sk_security;
3693                 sksec->sid = isec->sid;
3694                 sksec->sclass = isec->sclass;
3695                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3696         }
3697
3698         return err;
3699 }
3700
3701 /* Range of port numbers used to automatically bind.
3702    Need to determine whether we should perform a name_bind
3703    permission check between the socket and the port number. */
3704
3705 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3706 {
3707         struct sock *sk = sock->sk;
3708         u16 family;
3709         int err;
3710
3711         err = sock_has_perm(current, sk, SOCKET__BIND);
3712         if (err)
3713                 goto out;
3714
3715         /*
3716          * If PF_INET or PF_INET6, check name_bind permission for the port.
3717          * Multiple address binding for SCTP is not supported yet: we just
3718          * check the first address now.
3719          */
3720         family = sk->sk_family;
3721         if (family == PF_INET || family == PF_INET6) {
3722                 char *addrp;
3723                 struct sk_security_struct *sksec = sk->sk_security;
3724                 struct common_audit_data ad;
3725                 struct sockaddr_in *addr4 = NULL;
3726                 struct sockaddr_in6 *addr6 = NULL;
3727                 unsigned short snum;
3728                 u32 sid, node_perm;
3729
3730                 if (family == PF_INET) {
3731                         addr4 = (struct sockaddr_in *)address;
3732                         snum = ntohs(addr4->sin_port);
3733                         addrp = (char *)&addr4->sin_addr.s_addr;
3734                 } else {
3735                         addr6 = (struct sockaddr_in6 *)address;
3736                         snum = ntohs(addr6->sin6_port);
3737                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3738                 }
3739
3740                 if (snum) {
3741                         int low, high;
3742
3743                         inet_get_local_port_range(&low, &high);
3744
3745                         if (snum < max(PROT_SOCK, low) || snum > high) {
3746                                 err = sel_netport_sid(sk->sk_protocol,
3747                                                       snum, &sid);
3748                                 if (err)
3749                                         goto out;
3750                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3751                                 ad.u.net.sport = htons(snum);
3752                                 ad.u.net.family = family;
3753                                 err = avc_has_perm(sksec->sid, sid,
3754                                                    sksec->sclass,
3755                                                    SOCKET__NAME_BIND, &ad);
3756                                 if (err)
3757                                         goto out;
3758                         }
3759                 }
3760
3761                 switch (sksec->sclass) {
3762                 case SECCLASS_TCP_SOCKET:
3763                         node_perm = TCP_SOCKET__NODE_BIND;
3764                         break;
3765
3766                 case SECCLASS_UDP_SOCKET:
3767                         node_perm = UDP_SOCKET__NODE_BIND;
3768                         break;
3769
3770                 case SECCLASS_DCCP_SOCKET:
3771                         node_perm = DCCP_SOCKET__NODE_BIND;
3772                         break;
3773
3774                 default:
3775                         node_perm = RAWIP_SOCKET__NODE_BIND;
3776                         break;
3777                 }
3778
3779                 err = sel_netnode_sid(addrp, family, &sid);
3780                 if (err)
3781                         goto out;
3782
3783                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3784                 ad.u.net.sport = htons(snum);
3785                 ad.u.net.family = family;
3786
3787                 if (family == PF_INET)
3788                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3789                 else
3790                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3791
3792                 err = avc_has_perm(sksec->sid, sid,
3793                                    sksec->sclass, node_perm, &ad);
3794                 if (err)
3795                         goto out;
3796         }
3797 out:
3798         return err;
3799 }
3800
3801 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3802 {
3803         struct sock *sk = sock->sk;
3804         struct sk_security_struct *sksec = sk->sk_security;
3805         int err;
3806
3807         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3808         if (err)
3809                 return err;
3810
3811         /*
3812          * If a TCP or DCCP socket, check name_connect permission for the port.
3813          */
3814         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3815             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3816                 struct common_audit_data ad;
3817                 struct sockaddr_in *addr4 = NULL;
3818                 struct sockaddr_in6 *addr6 = NULL;
3819                 unsigned short snum;
3820                 u32 sid, perm;
3821
3822                 if (sk->sk_family == PF_INET) {
3823                         addr4 = (struct sockaddr_in *)address;
3824                         if (addrlen < sizeof(struct sockaddr_in))
3825                                 return -EINVAL;
3826                         snum = ntohs(addr4->sin_port);
3827                 } else {
3828                         addr6 = (struct sockaddr_in6 *)address;
3829                         if (addrlen < SIN6_LEN_RFC2133)
3830                                 return -EINVAL;
3831                         snum = ntohs(addr6->sin6_port);
3832                 }
3833
3834                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3835                 if (err)
3836                         goto out;
3837
3838                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3839                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3840
3841                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3842                 ad.u.net.dport = htons(snum);
3843                 ad.u.net.family = sk->sk_family;
3844                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3845                 if (err)
3846                         goto out;
3847         }
3848
3849         err = selinux_netlbl_socket_connect(sk, address);
3850
3851 out:
3852         return err;
3853 }
3854
3855 static int selinux_socket_listen(struct socket *sock, int backlog)
3856 {
3857         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3858 }
3859
3860 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3861 {
3862         int err;
3863         struct inode_security_struct *isec;
3864         struct inode_security_struct *newisec;
3865
3866         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3867         if (err)
3868                 return err;
3869
3870         newisec = SOCK_INODE(newsock)->i_security;
3871
3872         isec = SOCK_INODE(sock)->i_security;
3873         newisec->sclass = isec->sclass;
3874         newisec->sid = isec->sid;
3875         newisec->initialized = 1;
3876
3877         return 0;
3878 }
3879
3880 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3881                                   int size)
3882 {
3883         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3884 }
3885
3886 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3887                                   int size, int flags)
3888 {
3889         return sock_has_perm(current, sock->sk, SOCKET__READ);
3890 }
3891
3892 static int selinux_socket_getsockname(struct socket *sock)
3893 {
3894         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3895 }
3896
3897 static int selinux_socket_getpeername(struct socket *sock)
3898 {
3899         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3900 }
3901
3902 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3903 {
3904         int err;
3905
3906         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3907         if (err)
3908                 return err;
3909
3910         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3911 }
3912
3913 static int selinux_socket_getsockopt(struct socket *sock, int level,
3914                                      int optname)
3915 {
3916         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3917 }
3918
3919 static int selinux_socket_shutdown(struct socket *sock, int how)
3920 {
3921         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3922 }
3923
3924 static int selinux_socket_unix_stream_connect(struct socket *sock,
3925                                               struct socket *other,
3926                                               struct sock *newsk)
3927 {
3928         struct sk_security_struct *sksec_sock = sock->sk->sk_security;
3929         struct sk_security_struct *sksec_other = other->sk->sk_security;
3930         struct sk_security_struct *sksec_new = newsk->sk_security;
3931         struct common_audit_data ad;
3932         int err;
3933
3934         COMMON_AUDIT_DATA_INIT(&ad, NET);
3935         ad.u.net.sk = other->sk;
3936
3937         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
3938                            sksec_other->sclass,
3939                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3940         if (err)
3941                 return err;
3942
3943         /* server child socket */
3944         sksec_new->peer_sid = sksec_sock->sid;
3945         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
3946                                     &sksec_new->sid);
3947         if (err)
3948                 return err;
3949
3950         /* connecting socket */
3951         sksec_sock->peer_sid = sksec_new->sid;
3952
3953         return 0;
3954 }
3955
3956 static int selinux_socket_unix_may_send(struct socket *sock,
3957                                         struct socket *other)
3958 {
3959         struct sk_security_struct *ssec = sock->sk->sk_security;
3960         struct sk_security_struct *osec = other->sk->sk_security;
3961         struct common_audit_data ad;
3962
3963         COMMON_AUDIT_DATA_INIT(&ad, NET);
3964         ad.u.net.sk = other->sk;
3965
3966         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
3967                             &ad);
3968 }
3969
3970 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3971                                     u32 peer_sid,
3972                                     struct common_audit_data *ad)
3973 {
3974         int err;
3975         u32 if_sid;
3976         u32 node_sid;
3977
3978         err = sel_netif_sid(ifindex, &if_sid);
3979         if (err)
3980                 return err;
3981         err = avc_has_perm(peer_sid, if_sid,
3982                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3983         if (err)
3984                 return err;
3985
3986         err = sel_netnode_sid(addrp, family, &node_sid);
3987         if (err)
3988                 return err;
3989         return avc_has_perm(peer_sid, node_sid,
3990                             SECCLASS_NODE, NODE__RECVFROM, ad);
3991 }
3992
3993 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
3994                                        u16 family)
3995 {
3996         int err = 0;
3997         struct sk_security_struct *sksec = sk->sk_security;
3998         u32 peer_sid;
3999         u32 sk_sid = sksec->sid;
4000         struct common_audit_data ad;
4001         char *addrp;
4002
4003         COMMON_AUDIT_DATA_INIT(&ad, NET);
4004         ad.u.net.netif = skb->skb_iif;
4005         ad.u.net.family = family;
4006         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4007         if (err)
4008                 return err;
4009
4010         if (selinux_secmark_enabled()) {
4011                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4012                                    PACKET__RECV, &ad);
4013                 if (err)
4014                         return err;
4015         }
4016
4017         if (selinux_policycap_netpeer) {
4018                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4019                 if (err)
4020                         return err;
4021                 err = avc_has_perm(sk_sid, peer_sid,
4022                                    SECCLASS_PEER, PEER__RECV, &ad);
4023                 if (err)
4024                         selinux_netlbl_err(skb, err, 0);
4025         } else {
4026                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4027                 if (err)
4028                         return err;
4029                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4030         }
4031
4032         return err;
4033 }
4034
4035 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4036 {
4037         int err;
4038         struct sk_security_struct *sksec = sk->sk_security;
4039         u16 family = sk->sk_family;
4040         u32 sk_sid = sksec->sid;
4041         struct common_audit_data ad;
4042         char *addrp;
4043         u8 secmark_active;
4044         u8 peerlbl_active;
4045
4046         if (family != PF_INET && family != PF_INET6)
4047                 return 0;
4048
4049         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4050         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4051                 family = PF_INET;
4052
4053         /* If any sort of compatibility mode is enabled then handoff processing
4054          * to the selinux_sock_rcv_skb_compat() function to deal with the
4055          * special handling.  We do this in an attempt to keep this function
4056          * as fast and as clean as possible. */
4057         if (!selinux_policycap_netpeer)
4058                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4059
4060         secmark_active = selinux_secmark_enabled();
4061         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4062         if (!secmark_active && !peerlbl_active)
4063                 return 0;
4064
4065         COMMON_AUDIT_DATA_INIT(&ad, NET);
4066         ad.u.net.netif = skb->skb_iif;
4067         ad.u.net.family = family;
4068         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4069         if (err)
4070                 return err;
4071
4072         if (peerlbl_active) {
4073                 u32 peer_sid;
4074
4075                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4076                 if (err)
4077                         return err;
4078                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4079                                                peer_sid, &ad);
4080                 if (err) {
4081                         selinux_netlbl_err(skb, err, 0);
4082                         return err;
4083                 }
4084                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4085                                    PEER__RECV, &ad);
4086                 if (err)
4087                         selinux_netlbl_err(skb, err, 0);
4088         }
4089
4090         if (secmark_active) {
4091                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4092                                    PACKET__RECV, &ad);
4093                 if (err)
4094                         return err;
4095         }
4096
4097         return err;
4098 }
4099
4100 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4101                                             int __user *optlen, unsigned len)
4102 {
4103         int err = 0;
4104         char *scontext;
4105         u32 scontext_len;
4106         struct sk_security_struct *sksec = sock->sk->sk_security;
4107         u32 peer_sid = SECSID_NULL;
4108
4109         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4110             sksec->sclass == SECCLASS_TCP_SOCKET)
4111                 peer_sid = sksec->peer_sid;
4112         if (peer_sid == SECSID_NULL)
4113                 return -ENOPROTOOPT;
4114
4115         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4116         if (err)
4117                 return err;
4118
4119         if (scontext_len > len) {
4120                 err = -ERANGE;
4121                 goto out_len;
4122         }
4123
4124         if (copy_to_user(optval, scontext, scontext_len))
4125                 err = -EFAULT;
4126
4127 out_len:
4128         if (put_user(scontext_len, optlen))
4129                 err = -EFAULT;
4130         kfree(scontext);
4131         return err;
4132 }
4133
4134 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4135 {
4136         u32 peer_secid = SECSID_NULL;
4137         u16 family;
4138
4139         if (skb && skb->protocol == htons(ETH_P_IP))
4140                 family = PF_INET;
4141         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4142                 family = PF_INET6;
4143         else if (sock)
4144                 family = sock->sk->sk_family;
4145         else
4146                 goto out;
4147
4148         if (sock && family == PF_UNIX)
4149                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4150         else if (skb)
4151                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4152
4153 out:
4154         *secid = peer_secid;
4155         if (peer_secid == SECSID_NULL)
4156                 return -EINVAL;
4157         return 0;
4158 }
4159
4160 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4161 {
4162         struct sk_security_struct *sksec;
4163
4164         sksec = kzalloc(sizeof(*sksec), priority);
4165         if (!sksec)
4166                 return -ENOMEM;
4167
4168         sksec->peer_sid = SECINITSID_UNLABELED;
4169         sksec->sid = SECINITSID_UNLABELED;
4170         selinux_netlbl_sk_security_reset(sksec);
4171         sk->sk_security = sksec;
4172
4173         return 0;
4174 }
4175
4176 static void selinux_sk_free_security(struct sock *sk)
4177 {
4178         struct sk_security_struct *sksec = sk->sk_security;
4179
4180         sk->sk_security = NULL;
4181         selinux_netlbl_sk_security_free(sksec);
4182         kfree(sksec);
4183 }
4184
4185 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4186 {
4187         struct sk_security_struct *sksec = sk->sk_security;
4188         struct sk_security_struct *newsksec = newsk->sk_security;
4189
4190         newsksec->sid = sksec->sid;
4191         newsksec->peer_sid = sksec->peer_sid;
4192         newsksec->sclass = sksec->sclass;
4193
4194         selinux_netlbl_sk_security_reset(newsksec);
4195 }
4196
4197 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4198 {
4199         if (!sk)
4200                 *secid = SECINITSID_ANY_SOCKET;
4201         else {
4202                 struct sk_security_struct *sksec = sk->sk_security;
4203
4204                 *secid = sksec->sid;
4205         }
4206 }
4207
4208 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4209 {
4210         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4211         struct sk_security_struct *sksec = sk->sk_security;
4212
4213         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4214             sk->sk_family == PF_UNIX)
4215                 isec->sid = sksec->sid;
4216         sksec->sclass = isec->sclass;
4217 }
4218
4219 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4220                                      struct request_sock *req)
4221 {
4222         struct sk_security_struct *sksec = sk->sk_security;
4223         int err;
4224         u16 family = sk->sk_family;
4225         u32 newsid;
4226         u32 peersid;
4227
4228         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4229         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4230                 family = PF_INET;
4231
4232         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4233         if (err)
4234                 return err;
4235         if (peersid == SECSID_NULL) {
4236                 req->secid = sksec->sid;
4237                 req->peer_secid = SECSID_NULL;
4238         } else {
4239                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4240                 if (err)
4241                         return err;
4242                 req->secid = newsid;
4243                 req->peer_secid = peersid;
4244         }
4245
4246         return selinux_netlbl_inet_conn_request(req, family);
4247 }
4248
4249 static void selinux_inet_csk_clone(struct sock *newsk,
4250                                    const struct request_sock *req)
4251 {
4252         struct sk_security_struct *newsksec = newsk->sk_security;
4253
4254         newsksec->sid = req->secid;
4255         newsksec->peer_sid = req->peer_secid;
4256         /* NOTE: Ideally, we should also get the isec->sid for the
4257            new socket in sync, but we don't have the isec available yet.
4258            So we will wait until sock_graft to do it, by which
4259            time it will have been created and available. */
4260
4261         /* We don't need to take any sort of lock here as we are the only
4262          * thread with access to newsksec */
4263         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4264 }
4265
4266 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4267 {
4268         u16 family = sk->sk_family;
4269         struct sk_security_struct *sksec = sk->sk_security;
4270
4271         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4272         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4273                 family = PF_INET;
4274
4275         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4276 }
4277
4278 static int selinux_secmark_relabel_packet(u32 sid)
4279 {
4280         const struct task_security_struct *__tsec;
4281         u32 tsid;
4282
4283         __tsec = current_security();
4284         tsid = __tsec->sid;
4285
4286         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4287 }
4288
4289 static void selinux_secmark_refcount_inc(void)
4290 {
4291         atomic_inc(&selinux_secmark_refcount);
4292 }
4293
4294 static void selinux_secmark_refcount_dec(void)
4295 {
4296         atomic_dec(&selinux_secmark_refcount);
4297 }
4298
4299 static void selinux_req_classify_flow(const struct request_sock *req,
4300                                       struct flowi *fl)
4301 {
4302         fl->secid = req->secid;
4303 }
4304
4305 static int selinux_tun_dev_create(void)
4306 {
4307         u32 sid = current_sid();
4308
4309         /* we aren't taking into account the "sockcreate" SID since the socket
4310          * that is being created here is not a socket in the traditional sense,
4311          * instead it is a private sock, accessible only to the kernel, and
4312          * representing a wide range of network traffic spanning multiple
4313          * connections unlike traditional sockets - check the TUN driver to
4314          * get a better understanding of why this socket is special */
4315
4316         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4317                             NULL);
4318 }
4319
4320 static void selinux_tun_dev_post_create(struct sock *sk)
4321 {
4322         struct sk_security_struct *sksec = sk->sk_security;
4323
4324         /* we don't currently perform any NetLabel based labeling here and it
4325          * isn't clear that we would want to do so anyway; while we could apply
4326          * labeling without the support of the TUN user the resulting labeled
4327          * traffic from the other end of the connection would almost certainly
4328          * cause confusion to the TUN user that had no idea network labeling
4329          * protocols were being used */
4330
4331         /* see the comments in selinux_tun_dev_create() about why we don't use
4332          * the sockcreate SID here */
4333
4334         sksec->sid = current_sid();
4335         sksec->sclass = SECCLASS_TUN_SOCKET;
4336 }
4337
4338 static int selinux_tun_dev_attach(struct sock *sk)
4339 {
4340         struct sk_security_struct *sksec = sk->sk_security;
4341         u32 sid = current_sid();
4342         int err;
4343
4344         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4345                            TUN_SOCKET__RELABELFROM, NULL);
4346         if (err)
4347                 return err;
4348         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4349                            TUN_SOCKET__RELABELTO, NULL);
4350         if (err)
4351                 return err;
4352
4353         sksec->sid = sid;
4354
4355         return 0;
4356 }
4357
4358 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4359 {
4360         int err = 0;
4361         u32 perm;
4362         struct nlmsghdr *nlh;
4363         struct sk_security_struct *sksec = sk->sk_security;
4364
4365         if (skb->len < NLMSG_SPACE(0)) {
4366                 err = -EINVAL;
4367                 goto out;
4368         }
4369         nlh = nlmsg_hdr(skb);
4370
4371         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4372         if (err) {
4373                 if (err == -EINVAL) {
4374                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4375                                   "SELinux:  unrecognized netlink message"
4376                                   " type=%hu for sclass=%hu\n",
4377                                   nlh->nlmsg_type, sksec->sclass);
4378                         if (!selinux_enforcing || security_get_allow_unknown())
4379                                 err = 0;
4380                 }
4381
4382                 /* Ignore */
4383                 if (err == -ENOENT)
4384                         err = 0;
4385                 goto out;
4386         }
4387
4388         err = sock_has_perm(current, sk, perm);
4389 out:
4390         return err;
4391 }
4392
4393 #ifdef CONFIG_NETFILTER
4394
4395 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4396                                        u16 family)
4397 {
4398         int err;
4399         char *addrp;
4400         u32 peer_sid;
4401         struct common_audit_data ad;
4402         u8 secmark_active;
4403         u8 netlbl_active;
4404         u8 peerlbl_active;
4405
4406         if (!selinux_policycap_netpeer)
4407                 return NF_ACCEPT;
4408
4409         secmark_active = selinux_secmark_enabled();
4410         netlbl_active = netlbl_enabled();
4411         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4412         if (!secmark_active && !peerlbl_active)
4413                 return NF_ACCEPT;
4414
4415         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4416                 return NF_DROP;
4417
4418         COMMON_AUDIT_DATA_INIT(&ad, NET);
4419         ad.u.net.netif = ifindex;
4420         ad.u.net.family = family;
4421         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4422                 return NF_DROP;
4423
4424         if (peerlbl_active) {
4425                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4426                                                peer_sid, &ad);
4427                 if (err) {
4428                         selinux_netlbl_err(skb, err, 1);
4429                         return NF_DROP;
4430                 }
4431         }
4432
4433         if (secmark_active)
4434                 if (avc_has_perm(peer_sid, skb->secmark,
4435                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4436                         return NF_DROP;
4437
4438         if (netlbl_active)
4439                 /* we do this in the FORWARD path and not the POST_ROUTING
4440                  * path because we want to make sure we apply the necessary
4441                  * labeling before IPsec is applied so we can leverage AH
4442                  * protection */
4443                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4444                         return NF_DROP;
4445
4446         return NF_ACCEPT;
4447 }
4448
4449 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4450                                          struct sk_buff *skb,
4451                                          const struct net_device *in,
4452                                          const struct net_device *out,
4453                                          int (*okfn)(struct sk_buff *))
4454 {
4455         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4456 }
4457
4458 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4459 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4460                                          struct sk_buff *skb,
4461                                          const struct net_device *in,
4462                                          const struct net_device *out,
4463                                          int (*okfn)(struct sk_buff *))
4464 {
4465         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4466 }
4467 #endif  /* IPV6 */
4468
4469 static unsigned int selinux_ip_output(struct sk_buff *skb,
4470                                       u16 family)
4471 {
4472         u32 sid;
4473
4474         if (!netlbl_enabled())
4475                 return NF_ACCEPT;
4476
4477         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4478          * because we want to make sure we apply the necessary labeling
4479          * before IPsec is applied so we can leverage AH protection */
4480         if (skb->sk) {
4481                 struct sk_security_struct *sksec = skb->sk->sk_security;
4482                 sid = sksec->sid;
4483         } else
4484                 sid = SECINITSID_KERNEL;
4485         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4486                 return NF_DROP;
4487
4488         return NF_ACCEPT;
4489 }
4490
4491 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4492                                         struct sk_buff *skb,
4493                                         const struct net_device *in,
4494                                         const struct net_device *out,
4495                                         int (*okfn)(struct sk_buff *))
4496 {
4497         return selinux_ip_output(skb, PF_INET);
4498 }
4499
4500 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4501                                                 int ifindex,
4502                                                 u16 family)
4503 {
4504         struct sock *sk = skb->sk;
4505         struct sk_security_struct *sksec;
4506         struct common_audit_data ad;
4507         char *addrp;
4508         u8 proto;
4509
4510         if (sk == NULL)
4511                 return NF_ACCEPT;
4512         sksec = sk->sk_security;
4513
4514         COMMON_AUDIT_DATA_INIT(&ad, NET);
4515         ad.u.net.netif = ifindex;
4516         ad.u.net.family = family;
4517         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4518                 return NF_DROP;
4519
4520         if (selinux_secmark_enabled())
4521                 if (avc_has_perm(sksec->sid, skb->secmark,
4522                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4523                         return NF_DROP;
4524
4525         if (selinux_policycap_netpeer)
4526                 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4527                         return NF_DROP;
4528
4529         return NF_ACCEPT;
4530 }
4531
4532 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4533                                          u16 family)
4534 {
4535         u32 secmark_perm;
4536         u32 peer_sid;
4537         struct sock *sk;
4538         struct common_audit_data ad;
4539         char *addrp;
4540         u8 secmark_active;
4541         u8 peerlbl_active;
4542
4543         /* If any sort of compatibility mode is enabled then handoff processing
4544          * to the selinux_ip_postroute_compat() function to deal with the
4545          * special handling.  We do this in an attempt to keep this function
4546          * as fast and as clean as possible. */
4547         if (!selinux_policycap_netpeer)
4548                 return selinux_ip_postroute_compat(skb, ifindex, family);
4549 #ifdef CONFIG_XFRM
4550         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4551          * packet transformation so allow the packet to pass without any checks
4552          * since we'll have another chance to perform access control checks
4553          * when the packet is on it's final way out.
4554          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4555          *       is NULL, in this case go ahead and apply access control. */
4556         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4557                 return NF_ACCEPT;
4558 #endif
4559         secmark_active = selinux_secmark_enabled();
4560         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4561         if (!secmark_active && !peerlbl_active)
4562                 return NF_ACCEPT;
4563
4564         /* if the packet is being forwarded then get the peer label from the
4565          * packet itself; otherwise check to see if it is from a local
4566          * application or the kernel, if from an application get the peer label
4567          * from the sending socket, otherwise use the kernel's sid */
4568         sk = skb->sk;
4569         if (sk == NULL) {
4570                 switch (family) {
4571                 case PF_INET:
4572                         if (IPCB(skb)->flags & IPSKB_FORWARDED)
4573                                 secmark_perm = PACKET__FORWARD_OUT;
4574                         else
4575                                 secmark_perm = PACKET__SEND;
4576                         break;
4577                 case PF_INET6:
4578                         if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
4579                                 secmark_perm = PACKET__FORWARD_OUT;
4580                         else
4581                                 secmark_perm = PACKET__SEND;
4582                         break;
4583                 default:
4584                         return NF_DROP;
4585                 }
4586                 if (secmark_perm == PACKET__FORWARD_OUT) {
4587                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4588                                 return NF_DROP;
4589                 } else
4590                         peer_sid = SECINITSID_KERNEL;
4591         } else {
4592                 struct sk_security_struct *sksec = sk->sk_security;
4593                 peer_sid = sksec->sid;
4594                 secmark_perm = PACKET__SEND;
4595         }
4596
4597         COMMON_AUDIT_DATA_INIT(&ad, NET);
4598         ad.u.net.netif = ifindex;
4599         ad.u.net.family = family;
4600         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4601                 return NF_DROP;
4602
4603         if (secmark_active)
4604                 if (avc_has_perm(peer_sid, skb->secmark,
4605                                  SECCLASS_PACKET, secmark_perm, &ad))
4606                         return NF_DROP;
4607
4608         if (peerlbl_active) {
4609                 u32 if_sid;
4610                 u32 node_sid;
4611
4612                 if (sel_netif_sid(ifindex, &if_sid))
4613                         return NF_DROP;
4614                 if (avc_has_perm(peer_sid, if_sid,
4615                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4616                         return NF_DROP;
4617
4618                 if (sel_netnode_sid(addrp, family, &node_sid))
4619                         return NF_DROP;
4620                 if (avc_has_perm(peer_sid, node_sid,
4621                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4622                         return NF_DROP;
4623         }
4624
4625         return NF_ACCEPT;
4626 }
4627
4628 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4629                                            struct sk_buff *skb,
4630                                            const struct net_device *in,
4631                                            const struct net_device *out,
4632                                            int (*okfn)(struct sk_buff *))
4633 {
4634         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4635 }
4636
4637 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4638 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4639                                            struct sk_buff *skb,
4640                                            const struct net_device *in,
4641                                            const struct net_device *out,
4642                                            int (*okfn)(struct sk_buff *))
4643 {
4644         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4645 }
4646 #endif  /* IPV6 */
4647
4648 #endif  /* CONFIG_NETFILTER */
4649
4650 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4651 {
4652         int err;
4653
4654         err = cap_netlink_send(sk, skb);
4655         if (err)
4656                 return err;
4657
4658         return selinux_nlmsg_perm(sk, skb);
4659 }
4660
4661 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4662 {
4663         int err;
4664         struct common_audit_data ad;
4665
4666         err = cap_netlink_recv(skb, capability);
4667         if (err)
4668                 return err;
4669
4670         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4671         ad.u.cap = capability;
4672
4673         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4674                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4675 }
4676
4677 static int ipc_alloc_security(struct task_struct *task,
4678                               struct kern_ipc_perm *perm,
4679                               u16 sclass)
4680 {
4681         struct ipc_security_struct *isec;
4682         u32 sid;
4683
4684         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4685         if (!isec)
4686                 return -ENOMEM;
4687
4688         sid = task_sid(task);
4689         isec->sclass = sclass;
4690         isec->sid = sid;
4691         perm->security = isec;
4692
4693         return 0;
4694 }
4695
4696 static void ipc_free_security(struct kern_ipc_perm *perm)
4697 {
4698         struct ipc_security_struct *isec = perm->security;
4699         perm->security = NULL;
4700         kfree(isec);
4701 }
4702
4703 static int msg_msg_alloc_security(struct msg_msg *msg)
4704 {
4705         struct msg_security_struct *msec;
4706
4707         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4708         if (!msec)
4709                 return -ENOMEM;
4710
4711         msec->sid = SECINITSID_UNLABELED;
4712         msg->security = msec;
4713
4714         return 0;
4715 }
4716
4717 static void msg_msg_free_security(struct msg_msg *msg)
4718 {
4719         struct msg_security_struct *msec = msg->security;
4720
4721         msg->security = NULL;
4722         kfree(msec);
4723 }
4724
4725 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4726                         u32 perms)
4727 {
4728         struct ipc_security_struct *isec;
4729         struct common_audit_data ad;
4730         u32 sid = current_sid();
4731
4732         isec = ipc_perms->security;
4733
4734         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4735         ad.u.ipc_id = ipc_perms->key;
4736
4737         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4738 }
4739
4740 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4741 {
4742         return msg_msg_alloc_security(msg);
4743 }
4744
4745 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4746 {
4747         msg_msg_free_security(msg);
4748 }
4749
4750 /* message queue security operations */
4751 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4752 {
4753         struct ipc_security_struct *isec;
4754         struct common_audit_data ad;
4755         u32 sid = current_sid();
4756         int rc;
4757
4758         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4759         if (rc)
4760                 return rc;
4761
4762         isec = msq->q_perm.security;
4763
4764         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4765         ad.u.ipc_id = msq->q_perm.key;
4766
4767         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4768                           MSGQ__CREATE, &ad);
4769         if (rc) {
4770                 ipc_free_security(&msq->q_perm);
4771                 return rc;
4772         }
4773         return 0;
4774 }
4775
4776 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4777 {
4778         ipc_free_security(&msq->q_perm);
4779 }
4780
4781 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4782 {
4783         struct ipc_security_struct *isec;
4784         struct common_audit_data ad;
4785         u32 sid = current_sid();
4786
4787         isec = msq->q_perm.security;
4788
4789         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4790         ad.u.ipc_id = msq->q_perm.key;
4791
4792         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4793                             MSGQ__ASSOCIATE, &ad);
4794 }
4795
4796 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4797 {
4798         int err;
4799         int perms;
4800
4801         switch (cmd) {
4802         case IPC_INFO:
4803         case MSG_INFO:
4804                 /* No specific object, just general system-wide information. */
4805                 return task_has_system(current, SYSTEM__IPC_INFO);
4806         case IPC_STAT:
4807         case MSG_STAT:
4808                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4809                 break;
4810         case IPC_SET:
4811                 perms = MSGQ__SETATTR;
4812                 break;
4813         case IPC_RMID:
4814                 perms = MSGQ__DESTROY;
4815                 break;
4816         default:
4817                 return 0;
4818         }
4819
4820         err = ipc_has_perm(&msq->q_perm, perms);
4821         return err;
4822 }
4823
4824 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4825 {
4826         struct ipc_security_struct *isec;
4827         struct msg_security_struct *msec;
4828         struct common_audit_data ad;
4829         u32 sid = current_sid();
4830         int rc;
4831
4832         isec = msq->q_perm.security;
4833         msec = msg->security;
4834
4835         /*
4836          * First time through, need to assign label to the message
4837          */
4838         if (msec->sid == SECINITSID_UNLABELED) {
4839                 /*
4840                  * Compute new sid based on current process and
4841                  * message queue this message will be stored in
4842                  */
4843                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4844                                              &msec->sid);
4845                 if (rc)
4846                         return rc;
4847         }
4848
4849         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4850         ad.u.ipc_id = msq->q_perm.key;
4851
4852         /* Can this process write to the queue? */
4853         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4854                           MSGQ__WRITE, &ad);
4855         if (!rc)
4856                 /* Can this process send the message */
4857                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4858                                   MSG__SEND, &ad);
4859         if (!rc)
4860                 /* Can the message be put in the queue? */
4861                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4862                                   MSGQ__ENQUEUE, &ad);
4863
4864         return rc;
4865 }
4866
4867 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4868                                     struct task_struct *target,
4869                                     long type, int mode)
4870 {
4871         struct ipc_security_struct *isec;
4872         struct msg_security_struct *msec;
4873         struct common_audit_data ad;
4874         u32 sid = task_sid(target);
4875         int rc;
4876
4877         isec = msq->q_perm.security;
4878         msec = msg->security;
4879
4880         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4881         ad.u.ipc_id = msq->q_perm.key;
4882
4883         rc = avc_has_perm(sid, isec->sid,
4884                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4885         if (!rc)
4886                 rc = avc_has_perm(sid, msec->sid,
4887                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4888         return rc;
4889 }
4890
4891 /* Shared Memory security operations */
4892 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4893 {
4894         struct ipc_security_struct *isec;
4895         struct common_audit_data ad;
4896         u32 sid = current_sid();
4897         int rc;
4898
4899         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4900         if (rc)
4901                 return rc;
4902
4903         isec = shp->shm_perm.security;
4904
4905         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4906         ad.u.ipc_id = shp->shm_perm.key;
4907
4908         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4909                           SHM__CREATE, &ad);
4910         if (rc) {
4911                 ipc_free_security(&shp->shm_perm);
4912                 return rc;
4913         }
4914         return 0;
4915 }
4916
4917 static void selinux_shm_free_security(struct shmid_kernel *shp)
4918 {
4919         ipc_free_security(&shp->shm_perm);
4920 }
4921
4922 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4923 {
4924         struct ipc_security_struct *isec;
4925         struct common_audit_data ad;
4926         u32 sid = current_sid();
4927
4928         isec = shp->shm_perm.security;
4929
4930         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4931         ad.u.ipc_id = shp->shm_perm.key;
4932
4933         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4934                             SHM__ASSOCIATE, &ad);
4935 }
4936
4937 /* Note, at this point, shp is locked down */
4938 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4939 {
4940         int perms;
4941         int err;
4942
4943         switch (cmd) {
4944         case IPC_INFO:
4945         case SHM_INFO:
4946                 /* No specific object, just general system-wide information. */
4947                 return task_has_system(current, SYSTEM__IPC_INFO);
4948         case IPC_STAT:
4949         case SHM_STAT:
4950                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4951                 break;
4952         case IPC_SET:
4953                 perms = SHM__SETATTR;
4954                 break;
4955         case SHM_LOCK:
4956         case SHM_UNLOCK:
4957                 perms = SHM__LOCK;
4958                 break;
4959         case IPC_RMID:
4960                 perms = SHM__DESTROY;
4961                 break;
4962         default:
4963                 return 0;
4964         }
4965
4966         err = ipc_has_perm(&shp->shm_perm, perms);
4967         return err;
4968 }
4969
4970 static int selinux_shm_shmat(struct shmid_kernel *shp,
4971                              char __user *shmaddr, int shmflg)
4972 {
4973         u32 perms;
4974
4975         if (shmflg & SHM_RDONLY)
4976                 perms = SHM__READ;
4977         else
4978                 perms = SHM__READ | SHM__WRITE;
4979
4980         return ipc_has_perm(&shp->shm_perm, perms);
4981 }
4982
4983 /* Semaphore security operations */
4984 static int selinux_sem_alloc_security(struct sem_array *sma)
4985 {
4986         struct ipc_security_struct *isec;
4987         struct common_audit_data ad;
4988         u32 sid = current_sid();
4989         int rc;
4990
4991         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4992         if (rc)
4993                 return rc;
4994
4995         isec = sma->sem_perm.security;
4996
4997         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998         ad.u.ipc_id = sma->sem_perm.key;
4999
5000         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5001                           SEM__CREATE, &ad);
5002         if (rc) {
5003                 ipc_free_security(&sma->sem_perm);
5004                 return rc;
5005         }
5006         return 0;
5007 }
5008
5009 static void selinux_sem_free_security(struct sem_array *sma)
5010 {
5011         ipc_free_security(&sma->sem_perm);
5012 }
5013
5014 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5015 {
5016         struct ipc_security_struct *isec;
5017         struct common_audit_data ad;
5018         u32 sid = current_sid();
5019
5020         isec = sma->sem_perm.security;
5021
5022         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5023         ad.u.ipc_id = sma->sem_perm.key;
5024
5025         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5026                             SEM__ASSOCIATE, &ad);
5027 }
5028
5029 /* Note, at this point, sma is locked down */
5030 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5031 {
5032         int err;
5033         u32 perms;
5034
5035         switch (cmd) {
5036         case IPC_INFO:
5037         case SEM_INFO:
5038                 /* No specific object, just general system-wide information. */
5039                 return task_has_system(current, SYSTEM__IPC_INFO);
5040         case GETPID:
5041         case GETNCNT:
5042         case GETZCNT:
5043                 perms = SEM__GETATTR;
5044                 break;
5045         case GETVAL:
5046         case GETALL:
5047                 perms = SEM__READ;
5048                 break;
5049         case SETVAL:
5050         case SETALL:
5051                 perms = SEM__WRITE;
5052                 break;
5053         case IPC_RMID:
5054                 perms = SEM__DESTROY;
5055                 break;
5056         case IPC_SET:
5057                 perms = SEM__SETATTR;
5058                 break;
5059         case IPC_STAT:
5060         case SEM_STAT:
5061                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5062                 break;
5063         default:
5064                 return 0;
5065         }
5066
5067         err = ipc_has_perm(&sma->sem_perm, perms);
5068         return err;
5069 }
5070
5071 static int selinux_sem_semop(struct sem_array *sma,
5072                              struct sembuf *sops, unsigned nsops, int alter)
5073 {
5074         u32 perms;
5075
5076         if (alter)
5077                 perms = SEM__READ | SEM__WRITE;
5078         else
5079                 perms = SEM__READ;
5080
5081         return ipc_has_perm(&sma->sem_perm, perms);
5082 }
5083
5084 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5085 {
5086         u32 av = 0;
5087
5088         av = 0;
5089         if (flag & S_IRUGO)
5090                 av |= IPC__UNIX_READ;
5091         if (flag & S_IWUGO)
5092                 av |= IPC__UNIX_WRITE;
5093
5094         if (av == 0)
5095                 return 0;
5096
5097         return ipc_has_perm(ipcp, av);
5098 }
5099
5100 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5101 {
5102         struct ipc_security_struct *isec = ipcp->security;
5103         *secid = isec->sid;
5104 }
5105
5106 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5107 {
5108         if (inode)
5109                 inode_doinit_with_dentry(inode, dentry);
5110 }
5111
5112 static int selinux_getprocattr(struct task_struct *p,
5113                                char *name, char **value)
5114 {
5115         const struct task_security_struct *__tsec;
5116         u32 sid;
5117         int error;
5118         unsigned len;
5119
5120         if (current != p) {
5121                 error = current_has_perm(p, PROCESS__GETATTR);
5122                 if (error)
5123                         return error;
5124         }
5125
5126         rcu_read_lock();
5127         __tsec = __task_cred(p)->security;
5128
5129         if (!strcmp(name, "current"))
5130                 sid = __tsec->sid;
5131         else if (!strcmp(name, "prev"))
5132                 sid = __tsec->osid;
5133         else if (!strcmp(name, "exec"))
5134                 sid = __tsec->exec_sid;
5135         else if (!strcmp(name, "fscreate"))
5136                 sid = __tsec->create_sid;
5137         else if (!strcmp(name, "keycreate"))
5138                 sid = __tsec->keycreate_sid;
5139         else if (!strcmp(name, "sockcreate"))
5140                 sid = __tsec->sockcreate_sid;
5141         else
5142                 goto invalid;
5143         rcu_read_unlock();
5144
5145         if (!sid)
5146                 return 0;
5147
5148         error = security_sid_to_context(sid, value, &len);
5149         if (error)
5150                 return error;
5151         return len;
5152
5153 invalid:
5154         rcu_read_unlock();
5155         return -EINVAL;
5156 }
5157
5158 static int selinux_setprocattr(struct task_struct *p,
5159                                char *name, void *value, size_t size)
5160 {
5161         struct task_security_struct *tsec;
5162         struct task_struct *tracer;
5163         struct cred *new;
5164         u32 sid = 0, ptsid;
5165         int error;
5166         char *str = value;
5167
5168         if (current != p) {
5169                 /* SELinux only allows a process to change its own
5170                    security attributes. */
5171                 return -EACCES;
5172         }
5173
5174         /*
5175          * Basic control over ability to set these attributes at all.
5176          * current == p, but we'll pass them separately in case the
5177          * above restriction is ever removed.
5178          */
5179         if (!strcmp(name, "exec"))
5180                 error = current_has_perm(p, PROCESS__SETEXEC);
5181         else if (!strcmp(name, "fscreate"))
5182                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5183         else if (!strcmp(name, "keycreate"))
5184                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5185         else if (!strcmp(name, "sockcreate"))
5186                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5187         else if (!strcmp(name, "current"))
5188                 error = current_has_perm(p, PROCESS__SETCURRENT);
5189         else
5190                 error = -EINVAL;
5191         if (error)
5192                 return error;
5193
5194         /* Obtain a SID for the context, if one was specified. */
5195         if (size && str[1] && str[1] != '\n') {
5196                 if (str[size-1] == '\n') {
5197                         str[size-1] = 0;
5198                         size--;
5199                 }
5200                 error = security_context_to_sid(value, size, &sid);
5201                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5202                         if (!capable(CAP_MAC_ADMIN))
5203                                 return error;
5204                         error = security_context_to_sid_force(value, size,
5205                                                               &sid);
5206                 }
5207                 if (error)
5208                         return error;
5209         }
5210
5211         new = prepare_creds();
5212         if (!new)
5213                 return -ENOMEM;
5214
5215         /* Permission checking based on the specified context is
5216            performed during the actual operation (execve,
5217            open/mkdir/...), when we know the full context of the
5218            operation.  See selinux_bprm_set_creds for the execve
5219            checks and may_create for the file creation checks. The
5220            operation will then fail if the context is not permitted. */
5221         tsec = new->security;
5222         if (!strcmp(name, "exec")) {
5223                 tsec->exec_sid = sid;
5224         } else if (!strcmp(name, "fscreate")) {
5225                 tsec->create_sid = sid;
5226         } else if (!strcmp(name, "keycreate")) {
5227                 error = may_create_key(sid, p);
5228                 if (error)
5229                         goto abort_change;
5230                 tsec->keycreate_sid = sid;
5231         } else if (!strcmp(name, "sockcreate")) {
5232                 tsec->sockcreate_sid = sid;
5233         } else if (!strcmp(name, "current")) {
5234                 error = -EINVAL;
5235                 if (sid == 0)
5236                         goto abort_change;
5237
5238                 /* Only allow single threaded processes to change context */
5239                 error = -EPERM;
5240                 if (!current_is_single_threaded()) {
5241                         error = security_bounded_transition(tsec->sid, sid);
5242                         if (error)
5243                                 goto abort_change;
5244                 }
5245
5246                 /* Check permissions for the transition. */
5247                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5248                                      PROCESS__DYNTRANSITION, NULL);
5249                 if (error)
5250                         goto abort_change;
5251
5252                 /* Check for ptracing, and update the task SID if ok.
5253                    Otherwise, leave SID unchanged and fail. */
5254                 ptsid = 0;
5255                 task_lock(p);
5256                 tracer = tracehook_tracer_task(p);
5257                 if (tracer)
5258                         ptsid = task_sid(tracer);
5259                 task_unlock(p);
5260
5261                 if (tracer) {
5262                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5263                                              PROCESS__PTRACE, NULL);
5264                         if (error)
5265                                 goto abort_change;
5266                 }
5267
5268                 tsec->sid = sid;
5269         } else {
5270                 error = -EINVAL;
5271                 goto abort_change;
5272         }
5273
5274         commit_creds(new);
5275         return size;
5276
5277 abort_change:
5278         abort_creds(new);
5279         return error;
5280 }
5281
5282 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5283 {
5284         return security_sid_to_context(secid, secdata, seclen);
5285 }
5286
5287 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5288 {
5289         return security_context_to_sid(secdata, seclen, secid);
5290 }
5291
5292 static void selinux_release_secctx(char *secdata, u32 seclen)
5293 {
5294         kfree(secdata);
5295 }
5296
5297 /*
5298  *      called with inode->i_mutex locked
5299  */
5300 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5301 {
5302         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5303 }
5304
5305 /*
5306  *      called with inode->i_mutex locked
5307  */
5308 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5309 {
5310         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5311 }
5312
5313 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5314 {
5315         int len = 0;
5316         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5317                                                 ctx, true);
5318         if (len < 0)
5319                 return len;
5320         *ctxlen = len;
5321         return 0;
5322 }
5323 #ifdef CONFIG_KEYS
5324
5325 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5326                              unsigned long flags)
5327 {
5328         const struct task_security_struct *tsec;
5329         struct key_security_struct *ksec;
5330
5331         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5332         if (!ksec)
5333                 return -ENOMEM;
5334
5335         tsec = cred->security;
5336         if (tsec->keycreate_sid)
5337                 ksec->sid = tsec->keycreate_sid;
5338         else
5339                 ksec->sid = tsec->sid;
5340
5341         k->security = ksec;
5342         return 0;
5343 }
5344
5345 static void selinux_key_free(struct key *k)
5346 {
5347         struct key_security_struct *ksec = k->security;
5348
5349         k->security = NULL;
5350         kfree(ksec);
5351 }
5352
5353 static int selinux_key_permission(key_ref_t key_ref,
5354                                   const struct cred *cred,
5355                                   key_perm_t perm)
5356 {
5357         struct key *key;
5358         struct key_security_struct *ksec;
5359         u32 sid;
5360
5361         /* if no specific permissions are requested, we skip the
5362            permission check. No serious, additional covert channels
5363            appear to be created. */
5364         if (perm == 0)
5365                 return 0;
5366
5367         sid = cred_sid(cred);
5368
5369         key = key_ref_to_ptr(key_ref);
5370         ksec = key->security;
5371
5372         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5373 }
5374
5375 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5376 {
5377         struct key_security_struct *ksec = key->security;
5378         char *context = NULL;
5379         unsigned len;
5380         int rc;
5381
5382         rc = security_sid_to_context(ksec->sid, &context, &len);
5383         if (!rc)
5384                 rc = len;
5385         *_buffer = context;
5386         return rc;
5387 }
5388
5389 #endif
5390
5391 static struct security_operations selinux_ops = {
5392         .name =                         "selinux",
5393
5394         .ptrace_access_check =          selinux_ptrace_access_check,
5395         .ptrace_traceme =               selinux_ptrace_traceme,
5396         .capget =                       selinux_capget,
5397         .capset =                       selinux_capset,
5398         .sysctl =                       selinux_sysctl,
5399         .capable =                      selinux_capable,
5400         .quotactl =                     selinux_quotactl,
5401         .quota_on =                     selinux_quota_on,
5402         .syslog =                       selinux_syslog,
5403         .vm_enough_memory =             selinux_vm_enough_memory,
5404
5405         .netlink_send =                 selinux_netlink_send,
5406         .netlink_recv =                 selinux_netlink_recv,
5407
5408         .bprm_set_creds =               selinux_bprm_set_creds,
5409         .bprm_committing_creds =        selinux_bprm_committing_creds,
5410         .bprm_committed_creds =         selinux_bprm_committed_creds,
5411         .bprm_secureexec =              selinux_bprm_secureexec,
5412
5413         .sb_alloc_security =            selinux_sb_alloc_security,
5414         .sb_free_security =             selinux_sb_free_security,
5415         .sb_copy_data =                 selinux_sb_copy_data,
5416         .sb_kern_mount =                selinux_sb_kern_mount,
5417         .sb_show_options =              selinux_sb_show_options,
5418         .sb_statfs =                    selinux_sb_statfs,
5419         .sb_mount =                     selinux_mount,
5420         .sb_umount =                    selinux_umount,
5421         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5422         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5423         .sb_parse_opts_str =            selinux_parse_opts_str,
5424
5425
5426         .inode_alloc_security =         selinux_inode_alloc_security,
5427         .inode_free_security =          selinux_inode_free_security,
5428         .inode_init_security =          selinux_inode_init_security,
5429         .inode_create =                 selinux_inode_create,
5430         .inode_link =                   selinux_inode_link,
5431         .inode_unlink =                 selinux_inode_unlink,
5432         .inode_symlink =                selinux_inode_symlink,
5433         .inode_mkdir =                  selinux_inode_mkdir,
5434         .inode_rmdir =                  selinux_inode_rmdir,
5435         .inode_mknod =                  selinux_inode_mknod,
5436         .inode_rename =                 selinux_inode_rename,
5437         .inode_readlink =               selinux_inode_readlink,
5438         .inode_follow_link =            selinux_inode_follow_link,
5439         .inode_permission =             selinux_inode_permission,
5440         .inode_setattr =                selinux_inode_setattr,
5441         .inode_getattr =                selinux_inode_getattr,
5442         .inode_setxattr =               selinux_inode_setxattr,
5443         .inode_post_setxattr =          selinux_inode_post_setxattr,
5444         .inode_getxattr =               selinux_inode_getxattr,
5445         .inode_listxattr =              selinux_inode_listxattr,
5446         .inode_removexattr =            selinux_inode_removexattr,
5447         .inode_getsecurity =            selinux_inode_getsecurity,
5448         .inode_setsecurity =            selinux_inode_setsecurity,
5449         .inode_listsecurity =           selinux_inode_listsecurity,
5450         .inode_getsecid =               selinux_inode_getsecid,
5451
5452         .file_permission =              selinux_file_permission,
5453         .file_alloc_security =          selinux_file_alloc_security,
5454         .file_free_security =           selinux_file_free_security,
5455         .file_ioctl =                   selinux_file_ioctl,
5456         .file_mmap =                    selinux_file_mmap,
5457         .file_mprotect =                selinux_file_mprotect,
5458         .file_lock =                    selinux_file_lock,
5459         .file_fcntl =                   selinux_file_fcntl,
5460         .file_set_fowner =              selinux_file_set_fowner,
5461         .file_send_sigiotask =          selinux_file_send_sigiotask,
5462         .file_receive =                 selinux_file_receive,
5463
5464         .dentry_open =                  selinux_dentry_open,
5465
5466         .task_create =                  selinux_task_create,
5467         .cred_alloc_blank =             selinux_cred_alloc_blank,
5468         .cred_free =                    selinux_cred_free,
5469         .cred_prepare =                 selinux_cred_prepare,
5470         .cred_transfer =                selinux_cred_transfer,
5471         .kernel_act_as =                selinux_kernel_act_as,
5472         .kernel_create_files_as =       selinux_kernel_create_files_as,
5473         .kernel_module_request =        selinux_kernel_module_request,
5474         .task_setpgid =                 selinux_task_setpgid,
5475         .task_getpgid =                 selinux_task_getpgid,
5476         .task_getsid =                  selinux_task_getsid,
5477         .task_getsecid =                selinux_task_getsecid,
5478         .task_setnice =                 selinux_task_setnice,
5479         .task_setioprio =               selinux_task_setioprio,
5480         .task_getioprio =               selinux_task_getioprio,
5481         .task_setrlimit =               selinux_task_setrlimit,
5482         .task_setscheduler =            selinux_task_setscheduler,
5483         .task_getscheduler =            selinux_task_getscheduler,
5484         .task_movememory =              selinux_task_movememory,
5485         .task_kill =                    selinux_task_kill,
5486         .task_wait =                    selinux_task_wait,
5487         .task_to_inode =                selinux_task_to_inode,
5488
5489         .ipc_permission =               selinux_ipc_permission,
5490         .ipc_getsecid =                 selinux_ipc_getsecid,
5491
5492         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5493         .msg_msg_free_security =        selinux_msg_msg_free_security,
5494
5495         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5496         .msg_queue_free_security =      selinux_msg_queue_free_security,
5497         .msg_queue_associate =          selinux_msg_queue_associate,
5498         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5499         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5500         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5501
5502         .shm_alloc_security =           selinux_shm_alloc_security,
5503         .shm_free_security =            selinux_shm_free_security,
5504         .shm_associate =                selinux_shm_associate,
5505         .shm_shmctl =                   selinux_shm_shmctl,
5506         .shm_shmat =                    selinux_shm_shmat,
5507
5508         .sem_alloc_security =           selinux_sem_alloc_security,
5509         .sem_free_security =            selinux_sem_free_security,
5510         .sem_associate =                selinux_sem_associate,
5511         .sem_semctl =                   selinux_sem_semctl,
5512         .sem_semop =                    selinux_sem_semop,
5513
5514         .d_instantiate =                selinux_d_instantiate,
5515
5516         .getprocattr =                  selinux_getprocattr,
5517         .setprocattr =                  selinux_setprocattr,
5518
5519         .secid_to_secctx =              selinux_secid_to_secctx,
5520         .secctx_to_secid =              selinux_secctx_to_secid,
5521         .release_secctx =               selinux_release_secctx,
5522         .inode_notifysecctx =           selinux_inode_notifysecctx,
5523         .inode_setsecctx =              selinux_inode_setsecctx,
5524         .inode_getsecctx =              selinux_inode_getsecctx,
5525
5526         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5527         .unix_may_send =                selinux_socket_unix_may_send,
5528
5529         .socket_create =                selinux_socket_create,
5530         .socket_post_create =           selinux_socket_post_create,
5531         .socket_bind =                  selinux_socket_bind,
5532         .socket_connect =               selinux_socket_connect,
5533         .socket_listen =                selinux_socket_listen,
5534         .socket_accept =                selinux_socket_accept,
5535         .socket_sendmsg =               selinux_socket_sendmsg,
5536         .socket_recvmsg =               selinux_socket_recvmsg,
5537         .socket_getsockname =           selinux_socket_getsockname,
5538         .socket_getpeername =           selinux_socket_getpeername,
5539         .socket_getsockopt =            selinux_socket_getsockopt,
5540         .socket_setsockopt =            selinux_socket_setsockopt,
5541         .socket_shutdown =              selinux_socket_shutdown,
5542         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5543         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5544         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5545         .sk_alloc_security =            selinux_sk_alloc_security,
5546         .sk_free_security =             selinux_sk_free_security,
5547         .sk_clone_security =            selinux_sk_clone_security,
5548         .sk_getsecid =                  selinux_sk_getsecid,
5549         .sock_graft =                   selinux_sock_graft,
5550         .inet_conn_request =            selinux_inet_conn_request,
5551         .inet_csk_clone =               selinux_inet_csk_clone,
5552         .inet_conn_established =        selinux_inet_conn_established,
5553         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5554         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5555         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5556         .req_classify_flow =            selinux_req_classify_flow,
5557         .tun_dev_create =               selinux_tun_dev_create,
5558         .tun_dev_post_create =          selinux_tun_dev_post_create,
5559         .tun_dev_attach =               selinux_tun_dev_attach,
5560
5561 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5562         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5563         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5564         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5565         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5566         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5567         .xfrm_state_free_security =     selinux_xfrm_state_free,
5568         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5569         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5570         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5571         .xfrm_decode_session =          selinux_xfrm_decode_session,
5572 #endif
5573
5574 #ifdef CONFIG_KEYS
5575         .key_alloc =                    selinux_key_alloc,
5576         .key_free =                     selinux_key_free,
5577         .key_permission =               selinux_key_permission,
5578         .key_getsecurity =              selinux_key_getsecurity,
5579 #endif
5580
5581 #ifdef CONFIG_AUDIT
5582         .audit_rule_init =              selinux_audit_rule_init,
5583         .audit_rule_known =             selinux_audit_rule_known,
5584         .audit_rule_match =             selinux_audit_rule_match,
5585         .audit_rule_free =              selinux_audit_rule_free,
5586 #endif
5587 };
5588
5589 static __init int selinux_init(void)
5590 {
5591         if (!security_module_enable(&selinux_ops)) {
5592                 selinux_enabled = 0;
5593                 return 0;
5594         }
5595
5596         if (!selinux_enabled) {
5597                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5598                 return 0;
5599         }
5600
5601         printk(KERN_INFO "SELinux:  Initializing.\n");
5602
5603         /* Set the security state for the initial task. */
5604         cred_init_security();
5605
5606         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5607
5608         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5609                                             sizeof(struct inode_security_struct),
5610                                             0, SLAB_PANIC, NULL);
5611         avc_init();
5612
5613         if (register_security(&selinux_ops))
5614                 panic("SELinux: Unable to register with kernel.\n");
5615
5616         if (selinux_enforcing)
5617                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5618         else
5619                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5620
5621         return 0;
5622 }
5623
5624 static void delayed_superblock_init(struct super_block *sb, void *unused)
5625 {
5626         superblock_doinit(sb, NULL);
5627 }
5628
5629 void selinux_complete_init(void)
5630 {
5631         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5632
5633         /* Set up any superblocks initialized prior to the policy load. */
5634         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5635         iterate_supers(delayed_superblock_init, NULL);
5636 }
5637
5638 /* SELinux requires early initialization in order to label
5639    all processes and objects when they are created. */
5640 security_initcall(selinux_init);
5641
5642 #if defined(CONFIG_NETFILTER)
5643
5644 static struct nf_hook_ops selinux_ipv4_ops[] = {
5645         {
5646                 .hook =         selinux_ipv4_postroute,
5647                 .owner =        THIS_MODULE,
5648                 .pf =           PF_INET,
5649                 .hooknum =      NF_INET_POST_ROUTING,
5650                 .priority =     NF_IP_PRI_SELINUX_LAST,
5651         },
5652         {
5653                 .hook =         selinux_ipv4_forward,
5654                 .owner =        THIS_MODULE,
5655                 .pf =           PF_INET,
5656                 .hooknum =      NF_INET_FORWARD,
5657                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5658         },
5659         {
5660                 .hook =         selinux_ipv4_output,
5661                 .owner =        THIS_MODULE,
5662                 .pf =           PF_INET,
5663                 .hooknum =      NF_INET_LOCAL_OUT,
5664                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5665         }
5666 };
5667
5668 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5669
5670 static struct nf_hook_ops selinux_ipv6_ops[] = {
5671         {
5672                 .hook =         selinux_ipv6_postroute,
5673                 .owner =        THIS_MODULE,
5674                 .pf =           PF_INET6,
5675                 .hooknum =      NF_INET_POST_ROUTING,
5676                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5677         },
5678         {
5679                 .hook =         selinux_ipv6_forward,
5680                 .owner =        THIS_MODULE,
5681                 .pf =           PF_INET6,
5682                 .hooknum =      NF_INET_FORWARD,
5683                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5684         }
5685 };
5686
5687 #endif  /* IPV6 */
5688
5689 static int __init selinux_nf_ip_init(void)
5690 {
5691         int err = 0;
5692
5693         if (!selinux_enabled)
5694                 goto out;
5695
5696         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5697
5698         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5699         if (err)
5700                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5701
5702 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5703         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5704         if (err)
5705                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5706 #endif  /* IPV6 */
5707
5708 out:
5709         return err;
5710 }
5711
5712 __initcall(selinux_nf_ip_init);
5713
5714 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5715 static void selinux_nf_ip_exit(void)
5716 {
5717         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5718
5719         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5720 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5721         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5722 #endif  /* IPV6 */
5723 }
5724 #endif
5725
5726 #else /* CONFIG_NETFILTER */
5727
5728 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5729 #define selinux_nf_ip_exit()
5730 #endif
5731
5732 #endif /* CONFIG_NETFILTER */
5733
5734 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5735 static int selinux_disabled;
5736
5737 int selinux_disable(void)
5738 {
5739         extern void exit_sel_fs(void);
5740
5741         if (ss_initialized) {
5742                 /* Not permitted after initial policy load. */
5743                 return -EINVAL;
5744         }
5745
5746         if (selinux_disabled) {
5747                 /* Only do this once. */
5748                 return -EINVAL;
5749         }
5750
5751         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5752
5753         selinux_disabled = 1;
5754         selinux_enabled = 0;
5755
5756         reset_security_ops();
5757
5758         /* Try to destroy the avc node cache */
5759         avc_disable();
5760
5761         /* Unregister netfilter hooks. */
5762         selinux_nf_ip_exit();
5763
5764         /* Unregister selinuxfs. */
5765         exit_sel_fs();
5766
5767         return 0;
5768 }
5769 #endif