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SELinux: /proc/mounts should show what it can
[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 Hewlett-Packard Development Company, L.P.
17  *              Paul Moore <paul.moore@hp.com>
18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
20  *
21  *      This program is free software; you can redistribute it and/or modify
22  *      it under the terms of the GNU General Public License version 2,
23  *      as published by the Free Software Foundation.
24  */
25
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched.h>
31 #include <linux/security.h>
32 #include <linux/xattr.h>
33 #include <linux/capability.h>
34 #include <linux/unistd.h>
35 #include <linux/mm.h>
36 #include <linux/mman.h>
37 #include <linux/slab.h>
38 #include <linux/pagemap.h>
39 #include <linux/swap.h>
40 #include <linux/spinlock.h>
41 #include <linux/syscalls.h>
42 #include <linux/file.h>
43 #include <linux/fdtable.h>
44 #include <linux/namei.h>
45 #include <linux/mount.h>
46 #include <linux/proc_fs.h>
47 #include <linux/netfilter_ipv4.h>
48 #include <linux/netfilter_ipv6.h>
49 #include <linux/tty.h>
50 #include <net/icmp.h>
51 #include <net/ip.h>             /* for local_port_range[] */
52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
53 #include <net/net_namespace.h>
54 #include <net/netlabel.h>
55 #include <linux/uaccess.h>
56 #include <asm/ioctls.h>
57 #include <asm/atomic.h>
58 #include <linux/bitops.h>
59 #include <linux/interrupt.h>
60 #include <linux/netdevice.h>    /* for network interface checks */
61 #include <linux/netlink.h>
62 #include <linux/tcp.h>
63 #include <linux/udp.h>
64 #include <linux/dccp.h>
65 #include <linux/quota.h>
66 #include <linux/un.h>           /* for Unix socket types */
67 #include <net/af_unix.h>        /* for Unix socket types */
68 #include <linux/parser.h>
69 #include <linux/nfs_mount.h>
70 #include <net/ipv6.h>
71 #include <linux/hugetlb.h>
72 #include <linux/personality.h>
73 #include <linux/sysctl.h>
74 #include <linux/audit.h>
75 #include <linux/string.h>
76 #include <linux/selinux.h>
77 #include <linux/mutex.h>
78
79 #include "avc.h"
80 #include "objsec.h"
81 #include "netif.h"
82 #include "netnode.h"
83 #include "netport.h"
84 #include "xfrm.h"
85 #include "netlabel.h"
86 #include "audit.h"
87
88 #define XATTR_SELINUX_SUFFIX "selinux"
89 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
90
91 #define NUM_SEL_MNT_OPTS 4
92
93 extern unsigned int policydb_loaded_version;
94 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
95 extern int selinux_compat_net;
96 extern struct security_operations *security_ops;
97
98 /* SECMARK reference count */
99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102 int selinux_enforcing;
103
104 static int __init enforcing_setup(char *str)
105 {
106         unsigned long enforcing;
107         if (!strict_strtoul(str, 0, &enforcing))
108                 selinux_enforcing = enforcing ? 1 : 0;
109         return 1;
110 }
111 __setup("enforcing=", enforcing_setup);
112 #endif
113
114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117 static int __init selinux_enabled_setup(char *str)
118 {
119         unsigned long enabled;
120         if (!strict_strtoul(str, 0, &enabled))
121                 selinux_enabled = enabled ? 1 : 0;
122         return 1;
123 }
124 __setup("selinux=", selinux_enabled_setup);
125 #else
126 int selinux_enabled = 1;
127 #endif
128
129
130 /*
131  * Minimal support for a secondary security module,
132  * just to allow the use of the capability module.
133  */
134 static struct security_operations *secondary_ops;
135
136 /* Lists of inode and superblock security structures initialized
137    before the policy was loaded. */
138 static LIST_HEAD(superblock_security_head);
139 static DEFINE_SPINLOCK(sb_security_lock);
140
141 static struct kmem_cache *sel_inode_cache;
142
143 /**
144  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
145  *
146  * Description:
147  * This function checks the SECMARK reference counter to see if any SECMARK
148  * targets are currently configured, if the reference counter is greater than
149  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
150  * enabled, false (0) if SECMARK is disabled.
151  *
152  */
153 static int selinux_secmark_enabled(void)
154 {
155         return (atomic_read(&selinux_secmark_refcount) > 0);
156 }
157
158 /* Allocate and free functions for each kind of security blob. */
159
160 static int task_alloc_security(struct task_struct *task)
161 {
162         struct task_security_struct *tsec;
163
164         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
165         if (!tsec)
166                 return -ENOMEM;
167
168         tsec->osid = tsec->sid = SECINITSID_UNLABELED;
169         task->security = tsec;
170
171         return 0;
172 }
173
174 static void task_free_security(struct task_struct *task)
175 {
176         struct task_security_struct *tsec = task->security;
177         task->security = NULL;
178         kfree(tsec);
179 }
180
181 static int inode_alloc_security(struct inode *inode)
182 {
183         struct task_security_struct *tsec = current->security;
184         struct inode_security_struct *isec;
185
186         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
187         if (!isec)
188                 return -ENOMEM;
189
190         mutex_init(&isec->lock);
191         INIT_LIST_HEAD(&isec->list);
192         isec->inode = inode;
193         isec->sid = SECINITSID_UNLABELED;
194         isec->sclass = SECCLASS_FILE;
195         isec->task_sid = tsec->sid;
196         inode->i_security = isec;
197
198         return 0;
199 }
200
201 static void inode_free_security(struct inode *inode)
202 {
203         struct inode_security_struct *isec = inode->i_security;
204         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
205
206         spin_lock(&sbsec->isec_lock);
207         if (!list_empty(&isec->list))
208                 list_del_init(&isec->list);
209         spin_unlock(&sbsec->isec_lock);
210
211         inode->i_security = NULL;
212         kmem_cache_free(sel_inode_cache, isec);
213 }
214
215 static int file_alloc_security(struct file *file)
216 {
217         struct task_security_struct *tsec = current->security;
218         struct file_security_struct *fsec;
219
220         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
221         if (!fsec)
222                 return -ENOMEM;
223
224         fsec->sid = tsec->sid;
225         fsec->fown_sid = tsec->sid;
226         file->f_security = fsec;
227
228         return 0;
229 }
230
231 static void file_free_security(struct file *file)
232 {
233         struct file_security_struct *fsec = file->f_security;
234         file->f_security = NULL;
235         kfree(fsec);
236 }
237
238 static int superblock_alloc_security(struct super_block *sb)
239 {
240         struct superblock_security_struct *sbsec;
241
242         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
243         if (!sbsec)
244                 return -ENOMEM;
245
246         mutex_init(&sbsec->lock);
247         INIT_LIST_HEAD(&sbsec->list);
248         INIT_LIST_HEAD(&sbsec->isec_head);
249         spin_lock_init(&sbsec->isec_lock);
250         sbsec->sb = sb;
251         sbsec->sid = SECINITSID_UNLABELED;
252         sbsec->def_sid = SECINITSID_FILE;
253         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
254         sb->s_security = sbsec;
255
256         return 0;
257 }
258
259 static void superblock_free_security(struct super_block *sb)
260 {
261         struct superblock_security_struct *sbsec = sb->s_security;
262
263         spin_lock(&sb_security_lock);
264         if (!list_empty(&sbsec->list))
265                 list_del_init(&sbsec->list);
266         spin_unlock(&sb_security_lock);
267
268         sb->s_security = NULL;
269         kfree(sbsec);
270 }
271
272 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
273 {
274         struct sk_security_struct *ssec;
275
276         ssec = kzalloc(sizeof(*ssec), priority);
277         if (!ssec)
278                 return -ENOMEM;
279
280         ssec->peer_sid = SECINITSID_UNLABELED;
281         ssec->sid = SECINITSID_UNLABELED;
282         sk->sk_security = ssec;
283
284         selinux_netlbl_sk_security_reset(ssec, family);
285
286         return 0;
287 }
288
289 static void sk_free_security(struct sock *sk)
290 {
291         struct sk_security_struct *ssec = sk->sk_security;
292
293         sk->sk_security = NULL;
294         kfree(ssec);
295 }
296
297 /* The security server must be initialized before
298    any labeling or access decisions can be provided. */
299 extern int ss_initialized;
300
301 /* The file system's label must be initialized prior to use. */
302
303 static char *labeling_behaviors[6] = {
304         "uses xattr",
305         "uses transition SIDs",
306         "uses task SIDs",
307         "uses genfs_contexts",
308         "not configured for labeling",
309         "uses mountpoint labeling",
310 };
311
312 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
313
314 static inline int inode_doinit(struct inode *inode)
315 {
316         return inode_doinit_with_dentry(inode, NULL);
317 }
318
319 enum {
320         Opt_error = -1,
321         Opt_context = 1,
322         Opt_fscontext = 2,
323         Opt_defcontext = 3,
324         Opt_rootcontext = 4,
325 };
326
327 static match_table_t tokens = {
328         {Opt_context, CONTEXT_STR "%s"},
329         {Opt_fscontext, FSCONTEXT_STR "%s"},
330         {Opt_defcontext, DEFCONTEXT_STR "%s"},
331         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
332         {Opt_error, NULL},
333 };
334
335 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
336
337 static int may_context_mount_sb_relabel(u32 sid,
338                         struct superblock_security_struct *sbsec,
339                         struct task_security_struct *tsec)
340 {
341         int rc;
342
343         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
344                           FILESYSTEM__RELABELFROM, NULL);
345         if (rc)
346                 return rc;
347
348         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
349                           FILESYSTEM__RELABELTO, NULL);
350         return rc;
351 }
352
353 static int may_context_mount_inode_relabel(u32 sid,
354                         struct superblock_security_struct *sbsec,
355                         struct task_security_struct *tsec)
356 {
357         int rc;
358         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
359                           FILESYSTEM__RELABELFROM, NULL);
360         if (rc)
361                 return rc;
362
363         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
364                           FILESYSTEM__ASSOCIATE, NULL);
365         return rc;
366 }
367
368 static int sb_finish_set_opts(struct super_block *sb)
369 {
370         struct superblock_security_struct *sbsec = sb->s_security;
371         struct dentry *root = sb->s_root;
372         struct inode *root_inode = root->d_inode;
373         int rc = 0;
374
375         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
376                 /* Make sure that the xattr handler exists and that no
377                    error other than -ENODATA is returned by getxattr on
378                    the root directory.  -ENODATA is ok, as this may be
379                    the first boot of the SELinux kernel before we have
380                    assigned xattr values to the filesystem. */
381                 if (!root_inode->i_op->getxattr) {
382                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
383                                "xattr support\n", sb->s_id, sb->s_type->name);
384                         rc = -EOPNOTSUPP;
385                         goto out;
386                 }
387                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
388                 if (rc < 0 && rc != -ENODATA) {
389                         if (rc == -EOPNOTSUPP)
390                                 printk(KERN_WARNING "SELinux: (dev %s, type "
391                                        "%s) has no security xattr handler\n",
392                                        sb->s_id, sb->s_type->name);
393                         else
394                                 printk(KERN_WARNING "SELinux: (dev %s, type "
395                                        "%s) getxattr errno %d\n", sb->s_id,
396                                        sb->s_type->name, -rc);
397                         goto out;
398                 }
399         }
400
401         sbsec->initialized = 1;
402
403         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
405                        sb->s_id, sb->s_type->name);
406         else
407                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
408                        sb->s_id, sb->s_type->name,
409                        labeling_behaviors[sbsec->behavior-1]);
410
411         /* Initialize the root inode. */
412         rc = inode_doinit_with_dentry(root_inode, root);
413
414         /* Initialize any other inodes associated with the superblock, e.g.
415            inodes created prior to initial policy load or inodes created
416            during get_sb by a pseudo filesystem that directly
417            populates itself. */
418         spin_lock(&sbsec->isec_lock);
419 next_inode:
420         if (!list_empty(&sbsec->isec_head)) {
421                 struct inode_security_struct *isec =
422                                 list_entry(sbsec->isec_head.next,
423                                            struct inode_security_struct, list);
424                 struct inode *inode = isec->inode;
425                 spin_unlock(&sbsec->isec_lock);
426                 inode = igrab(inode);
427                 if (inode) {
428                         if (!IS_PRIVATE(inode))
429                                 inode_doinit(inode);
430                         iput(inode);
431                 }
432                 spin_lock(&sbsec->isec_lock);
433                 list_del_init(&isec->list);
434                 goto next_inode;
435         }
436         spin_unlock(&sbsec->isec_lock);
437 out:
438         return rc;
439 }
440
441 /*
442  * This function should allow an FS to ask what it's mount security
443  * options were so it can use those later for submounts, displaying
444  * mount options, or whatever.
445  */
446 static int selinux_get_mnt_opts(const struct super_block *sb,
447                                 struct security_mnt_opts *opts)
448 {
449         int rc = 0, i;
450         struct superblock_security_struct *sbsec = sb->s_security;
451         char *context = NULL;
452         u32 len;
453         char tmp;
454
455         security_init_mnt_opts(opts);
456
457         if (!sbsec->initialized)
458                 return -EINVAL;
459
460         if (!ss_initialized)
461                 return -EINVAL;
462
463         /*
464          * if we ever use sbsec flags for anything other than tracking mount
465          * settings this is going to need a mask
466          */
467         tmp = sbsec->flags;
468         /* count the number of mount options for this sb */
469         for (i = 0; i < 8; i++) {
470                 if (tmp & 0x01)
471                         opts->num_mnt_opts++;
472                 tmp >>= 1;
473         }
474
475         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
476         if (!opts->mnt_opts) {
477                 rc = -ENOMEM;
478                 goto out_free;
479         }
480
481         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
482         if (!opts->mnt_opts_flags) {
483                 rc = -ENOMEM;
484                 goto out_free;
485         }
486
487         i = 0;
488         if (sbsec->flags & FSCONTEXT_MNT) {
489                 rc = security_sid_to_context(sbsec->sid, &context, &len);
490                 if (rc)
491                         goto out_free;
492                 opts->mnt_opts[i] = context;
493                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
494         }
495         if (sbsec->flags & CONTEXT_MNT) {
496                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
497                 if (rc)
498                         goto out_free;
499                 opts->mnt_opts[i] = context;
500                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
501         }
502         if (sbsec->flags & DEFCONTEXT_MNT) {
503                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
504                 if (rc)
505                         goto out_free;
506                 opts->mnt_opts[i] = context;
507                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
508         }
509         if (sbsec->flags & ROOTCONTEXT_MNT) {
510                 struct inode *root = sbsec->sb->s_root->d_inode;
511                 struct inode_security_struct *isec = root->i_security;
512
513                 rc = security_sid_to_context(isec->sid, &context, &len);
514                 if (rc)
515                         goto out_free;
516                 opts->mnt_opts[i] = context;
517                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
518         }
519
520         BUG_ON(i != opts->num_mnt_opts);
521
522         return 0;
523
524 out_free:
525         security_free_mnt_opts(opts);
526         return rc;
527 }
528
529 static int bad_option(struct superblock_security_struct *sbsec, char flag,
530                       u32 old_sid, u32 new_sid)
531 {
532         /* check if the old mount command had the same options */
533         if (sbsec->initialized)
534                 if (!(sbsec->flags & flag) ||
535                     (old_sid != new_sid))
536                         return 1;
537
538         /* check if we were passed the same options twice,
539          * aka someone passed context=a,context=b
540          */
541         if (!sbsec->initialized)
542                 if (sbsec->flags & flag)
543                         return 1;
544         return 0;
545 }
546
547 /*
548  * Allow filesystems with binary mount data to explicitly set mount point
549  * labeling information.
550  */
551 static int selinux_set_mnt_opts(struct super_block *sb,
552                                 struct security_mnt_opts *opts)
553 {
554         int rc = 0, i;
555         struct task_security_struct *tsec = current->security;
556         struct superblock_security_struct *sbsec = sb->s_security;
557         const char *name = sb->s_type->name;
558         struct inode *inode = sbsec->sb->s_root->d_inode;
559         struct inode_security_struct *root_isec = inode->i_security;
560         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
561         u32 defcontext_sid = 0;
562         char **mount_options = opts->mnt_opts;
563         int *flags = opts->mnt_opts_flags;
564         int num_opts = opts->num_mnt_opts;
565
566         mutex_lock(&sbsec->lock);
567
568         if (!ss_initialized) {
569                 if (!num_opts) {
570                         /* Defer initialization until selinux_complete_init,
571                            after the initial policy is loaded and the security
572                            server is ready to handle calls. */
573                         spin_lock(&sb_security_lock);
574                         if (list_empty(&sbsec->list))
575                                 list_add(&sbsec->list, &superblock_security_head);
576                         spin_unlock(&sb_security_lock);
577                         goto out;
578                 }
579                 rc = -EINVAL;
580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581                         "before the security server is initialized\n");
582                 goto out;
583         }
584
585         /*
586          * Binary mount data FS will come through this function twice.  Once
587          * from an explicit call and once from the generic calls from the vfs.
588          * Since the generic VFS calls will not contain any security mount data
589          * we need to skip the double mount verification.
590          *
591          * This does open a hole in which we will not notice if the first
592          * mount using this sb set explict options and a second mount using
593          * this sb does not set any security options.  (The first options
594          * will be used for both mounts)
595          */
596         if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597             && (num_opts == 0))
598                 goto out;
599
600         /*
601          * parse the mount options, check if they are valid sids.
602          * also check if someone is trying to mount the same sb more
603          * than once with different security options.
604          */
605         for (i = 0; i < num_opts; i++) {
606                 u32 sid;
607                 rc = security_context_to_sid(mount_options[i],
608                                              strlen(mount_options[i]), &sid);
609                 if (rc) {
610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
612                                mount_options[i], sb->s_id, name, rc);
613                         goto out;
614                 }
615                 switch (flags[i]) {
616                 case FSCONTEXT_MNT:
617                         fscontext_sid = sid;
618
619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
620                                         fscontext_sid))
621                                 goto out_double_mount;
622
623                         sbsec->flags |= FSCONTEXT_MNT;
624                         break;
625                 case CONTEXT_MNT:
626                         context_sid = sid;
627
628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
629                                         context_sid))
630                                 goto out_double_mount;
631
632                         sbsec->flags |= CONTEXT_MNT;
633                         break;
634                 case ROOTCONTEXT_MNT:
635                         rootcontext_sid = sid;
636
637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
638                                         rootcontext_sid))
639                                 goto out_double_mount;
640
641                         sbsec->flags |= ROOTCONTEXT_MNT;
642
643                         break;
644                 case DEFCONTEXT_MNT:
645                         defcontext_sid = sid;
646
647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
648                                         defcontext_sid))
649                                 goto out_double_mount;
650
651                         sbsec->flags |= DEFCONTEXT_MNT;
652
653                         break;
654                 default:
655                         rc = -EINVAL;
656                         goto out;
657                 }
658         }
659
660         if (sbsec->initialized) {
661                 /* previously mounted with options, but not on this attempt? */
662                 if (sbsec->flags && !num_opts)
663                         goto out_double_mount;
664                 rc = 0;
665                 goto out;
666         }
667
668         if (strcmp(sb->s_type->name, "proc") == 0)
669                 sbsec->proc = 1;
670
671         /* Determine the labeling behavior to use for this filesystem type. */
672         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
673         if (rc) {
674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
675                        __func__, sb->s_type->name, rc);
676                 goto out;
677         }
678
679         /* sets the context of the superblock for the fs being mounted. */
680         if (fscontext_sid) {
681
682                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
683                 if (rc)
684                         goto out;
685
686                 sbsec->sid = fscontext_sid;
687         }
688
689         /*
690          * Switch to using mount point labeling behavior.
691          * sets the label used on all file below the mountpoint, and will set
692          * the superblock context if not already set.
693          */
694         if (context_sid) {
695                 if (!fscontext_sid) {
696                         rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
697                         if (rc)
698                                 goto out;
699                         sbsec->sid = context_sid;
700                 } else {
701                         rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
702                         if (rc)
703                                 goto out;
704                 }
705                 if (!rootcontext_sid)
706                         rootcontext_sid = context_sid;
707
708                 sbsec->mntpoint_sid = context_sid;
709                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
710         }
711
712         if (rootcontext_sid) {
713                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
714                 if (rc)
715                         goto out;
716
717                 root_isec->sid = rootcontext_sid;
718                 root_isec->initialized = 1;
719         }
720
721         if (defcontext_sid) {
722                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
723                         rc = -EINVAL;
724                         printk(KERN_WARNING "SELinux: defcontext option is "
725                                "invalid for this filesystem type\n");
726                         goto out;
727                 }
728
729                 if (defcontext_sid != sbsec->def_sid) {
730                         rc = may_context_mount_inode_relabel(defcontext_sid,
731                                                              sbsec, tsec);
732                         if (rc)
733                                 goto out;
734                 }
735
736                 sbsec->def_sid = defcontext_sid;
737         }
738
739         rc = sb_finish_set_opts(sb);
740 out:
741         mutex_unlock(&sbsec->lock);
742         return rc;
743 out_double_mount:
744         rc = -EINVAL;
745         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
746                "security settings for (dev %s, type %s)\n", sb->s_id, name);
747         goto out;
748 }
749
750 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
751                                         struct super_block *newsb)
752 {
753         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
754         struct superblock_security_struct *newsbsec = newsb->s_security;
755
756         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
757         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
758         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
759
760         /*
761          * if the parent was able to be mounted it clearly had no special lsm
762          * mount options.  thus we can safely put this sb on the list and deal
763          * with it later
764          */
765         if (!ss_initialized) {
766                 spin_lock(&sb_security_lock);
767                 if (list_empty(&newsbsec->list))
768                         list_add(&newsbsec->list, &superblock_security_head);
769                 spin_unlock(&sb_security_lock);
770                 return;
771         }
772
773         /* how can we clone if the old one wasn't set up?? */
774         BUG_ON(!oldsbsec->initialized);
775
776         /* if fs is reusing a sb, just let its options stand... */
777         if (newsbsec->initialized)
778                 return;
779
780         mutex_lock(&newsbsec->lock);
781
782         newsbsec->flags = oldsbsec->flags;
783
784         newsbsec->sid = oldsbsec->sid;
785         newsbsec->def_sid = oldsbsec->def_sid;
786         newsbsec->behavior = oldsbsec->behavior;
787
788         if (set_context) {
789                 u32 sid = oldsbsec->mntpoint_sid;
790
791                 if (!set_fscontext)
792                         newsbsec->sid = sid;
793                 if (!set_rootcontext) {
794                         struct inode *newinode = newsb->s_root->d_inode;
795                         struct inode_security_struct *newisec = newinode->i_security;
796                         newisec->sid = sid;
797                 }
798                 newsbsec->mntpoint_sid = sid;
799         }
800         if (set_rootcontext) {
801                 const struct inode *oldinode = oldsb->s_root->d_inode;
802                 const struct inode_security_struct *oldisec = oldinode->i_security;
803                 struct inode *newinode = newsb->s_root->d_inode;
804                 struct inode_security_struct *newisec = newinode->i_security;
805
806                 newisec->sid = oldisec->sid;
807         }
808
809         sb_finish_set_opts(newsb);
810         mutex_unlock(&newsbsec->lock);
811 }
812
813 static int selinux_parse_opts_str(char *options,
814                                   struct security_mnt_opts *opts)
815 {
816         char *p;
817         char *context = NULL, *defcontext = NULL;
818         char *fscontext = NULL, *rootcontext = NULL;
819         int rc, num_mnt_opts = 0;
820
821         opts->num_mnt_opts = 0;
822
823         /* Standard string-based options. */
824         while ((p = strsep(&options, "|")) != NULL) {
825                 int token;
826                 substring_t args[MAX_OPT_ARGS];
827
828                 if (!*p)
829                         continue;
830
831                 token = match_token(p, tokens, args);
832
833                 switch (token) {
834                 case Opt_context:
835                         if (context || defcontext) {
836                                 rc = -EINVAL;
837                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
838                                 goto out_err;
839                         }
840                         context = match_strdup(&args[0]);
841                         if (!context) {
842                                 rc = -ENOMEM;
843                                 goto out_err;
844                         }
845                         break;
846
847                 case Opt_fscontext:
848                         if (fscontext) {
849                                 rc = -EINVAL;
850                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
851                                 goto out_err;
852                         }
853                         fscontext = match_strdup(&args[0]);
854                         if (!fscontext) {
855                                 rc = -ENOMEM;
856                                 goto out_err;
857                         }
858                         break;
859
860                 case Opt_rootcontext:
861                         if (rootcontext) {
862                                 rc = -EINVAL;
863                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
864                                 goto out_err;
865                         }
866                         rootcontext = match_strdup(&args[0]);
867                         if (!rootcontext) {
868                                 rc = -ENOMEM;
869                                 goto out_err;
870                         }
871                         break;
872
873                 case Opt_defcontext:
874                         if (context || defcontext) {
875                                 rc = -EINVAL;
876                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
877                                 goto out_err;
878                         }
879                         defcontext = match_strdup(&args[0]);
880                         if (!defcontext) {
881                                 rc = -ENOMEM;
882                                 goto out_err;
883                         }
884                         break;
885
886                 default:
887                         rc = -EINVAL;
888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
889                         goto out_err;
890
891                 }
892         }
893
894         rc = -ENOMEM;
895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896         if (!opts->mnt_opts)
897                 goto out_err;
898
899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900         if (!opts->mnt_opts_flags) {
901                 kfree(opts->mnt_opts);
902                 goto out_err;
903         }
904
905         if (fscontext) {
906                 opts->mnt_opts[num_mnt_opts] = fscontext;
907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908         }
909         if (context) {
910                 opts->mnt_opts[num_mnt_opts] = context;
911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912         }
913         if (rootcontext) {
914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916         }
917         if (defcontext) {
918                 opts->mnt_opts[num_mnt_opts] = defcontext;
919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920         }
921
922         opts->num_mnt_opts = num_mnt_opts;
923         return 0;
924
925 out_err:
926         kfree(context);
927         kfree(defcontext);
928         kfree(fscontext);
929         kfree(rootcontext);
930         return rc;
931 }
932 /*
933  * string mount options parsing and call set the sbsec
934  */
935 static int superblock_doinit(struct super_block *sb, void *data)
936 {
937         int rc = 0;
938         char *options = data;
939         struct security_mnt_opts opts;
940
941         security_init_mnt_opts(&opts);
942
943         if (!data)
944                 goto out;
945
946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948         rc = selinux_parse_opts_str(options, &opts);
949         if (rc)
950                 goto out_err;
951
952 out:
953         rc = selinux_set_mnt_opts(sb, &opts);
954
955 out_err:
956         security_free_mnt_opts(&opts);
957         return rc;
958 }
959
960 void selinux_write_opts(struct seq_file *m, struct security_mnt_opts *opts)
961 {
962         int i;
963         char *prefix;
964
965         for (i = 0; i < opts->num_mnt_opts; i++) {
966                 char *has_comma = strchr(opts->mnt_opts[i], ',');
967
968                 switch (opts->mnt_opts_flags[i]) {
969                 case CONTEXT_MNT:
970                         prefix = CONTEXT_STR;
971                         break;
972                 case FSCONTEXT_MNT:
973                         prefix = FSCONTEXT_STR;
974                         break;
975                 case ROOTCONTEXT_MNT:
976                         prefix = ROOTCONTEXT_STR;
977                         break;
978                 case DEFCONTEXT_MNT:
979                         prefix = DEFCONTEXT_STR;
980                         break;
981                 default:
982                         BUG();
983                 };
984                 /* we need a comma before each option */
985                 seq_putc(m, ',');
986                 seq_puts(m, prefix);
987                 if (has_comma)
988                         seq_putc(m, '\"');
989                 seq_puts(m, opts->mnt_opts[i]);
990                 if (has_comma)
991                         seq_putc(m, '\"');
992         }
993 }
994
995 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
996 {
997         struct security_mnt_opts opts;
998         int rc;
999
1000         rc = selinux_get_mnt_opts(sb, &opts);
1001         if (rc) {
1002                 /* before policy load we may get EINVAL, don't show anything */
1003                 if (rc == -EINVAL)
1004                         rc = 0;
1005                 return rc;
1006         }
1007
1008         selinux_write_opts(m, &opts);
1009
1010         security_free_mnt_opts(&opts);
1011
1012         return rc;
1013 }
1014
1015 static inline u16 inode_mode_to_security_class(umode_t mode)
1016 {
1017         switch (mode & S_IFMT) {
1018         case S_IFSOCK:
1019                 return SECCLASS_SOCK_FILE;
1020         case S_IFLNK:
1021                 return SECCLASS_LNK_FILE;
1022         case S_IFREG:
1023                 return SECCLASS_FILE;
1024         case S_IFBLK:
1025                 return SECCLASS_BLK_FILE;
1026         case S_IFDIR:
1027                 return SECCLASS_DIR;
1028         case S_IFCHR:
1029                 return SECCLASS_CHR_FILE;
1030         case S_IFIFO:
1031                 return SECCLASS_FIFO_FILE;
1032
1033         }
1034
1035         return SECCLASS_FILE;
1036 }
1037
1038 static inline int default_protocol_stream(int protocol)
1039 {
1040         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1041 }
1042
1043 static inline int default_protocol_dgram(int protocol)
1044 {
1045         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1046 }
1047
1048 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1049 {
1050         switch (family) {
1051         case PF_UNIX:
1052                 switch (type) {
1053                 case SOCK_STREAM:
1054                 case SOCK_SEQPACKET:
1055                         return SECCLASS_UNIX_STREAM_SOCKET;
1056                 case SOCK_DGRAM:
1057                         return SECCLASS_UNIX_DGRAM_SOCKET;
1058                 }
1059                 break;
1060         case PF_INET:
1061         case PF_INET6:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                         if (default_protocol_stream(protocol))
1065                                 return SECCLASS_TCP_SOCKET;
1066                         else
1067                                 return SECCLASS_RAWIP_SOCKET;
1068                 case SOCK_DGRAM:
1069                         if (default_protocol_dgram(protocol))
1070                                 return SECCLASS_UDP_SOCKET;
1071                         else
1072                                 return SECCLASS_RAWIP_SOCKET;
1073                 case SOCK_DCCP:
1074                         return SECCLASS_DCCP_SOCKET;
1075                 default:
1076                         return SECCLASS_RAWIP_SOCKET;
1077                 }
1078                 break;
1079         case PF_NETLINK:
1080                 switch (protocol) {
1081                 case NETLINK_ROUTE:
1082                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1083                 case NETLINK_FIREWALL:
1084                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1085                 case NETLINK_INET_DIAG:
1086                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1087                 case NETLINK_NFLOG:
1088                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1089                 case NETLINK_XFRM:
1090                         return SECCLASS_NETLINK_XFRM_SOCKET;
1091                 case NETLINK_SELINUX:
1092                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1093                 case NETLINK_AUDIT:
1094                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1095                 case NETLINK_IP6_FW:
1096                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1097                 case NETLINK_DNRTMSG:
1098                         return SECCLASS_NETLINK_DNRT_SOCKET;
1099                 case NETLINK_KOBJECT_UEVENT:
1100                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1101                 default:
1102                         return SECCLASS_NETLINK_SOCKET;
1103                 }
1104         case PF_PACKET:
1105                 return SECCLASS_PACKET_SOCKET;
1106         case PF_KEY:
1107                 return SECCLASS_KEY_SOCKET;
1108         case PF_APPLETALK:
1109                 return SECCLASS_APPLETALK_SOCKET;
1110         }
1111
1112         return SECCLASS_SOCKET;
1113 }
1114
1115 #ifdef CONFIG_PROC_FS
1116 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1117                                 u16 tclass,
1118                                 u32 *sid)
1119 {
1120         int buflen, rc;
1121         char *buffer, *path, *end;
1122
1123         buffer = (char *)__get_free_page(GFP_KERNEL);
1124         if (!buffer)
1125                 return -ENOMEM;
1126
1127         buflen = PAGE_SIZE;
1128         end = buffer+buflen;
1129         *--end = '\0';
1130         buflen--;
1131         path = end-1;
1132         *path = '/';
1133         while (de && de != de->parent) {
1134                 buflen -= de->namelen + 1;
1135                 if (buflen < 0)
1136                         break;
1137                 end -= de->namelen;
1138                 memcpy(end, de->name, de->namelen);
1139                 *--end = '/';
1140                 path = end;
1141                 de = de->parent;
1142         }
1143         rc = security_genfs_sid("proc", path, tclass, sid);
1144         free_page((unsigned long)buffer);
1145         return rc;
1146 }
1147 #else
1148 static int selinux_proc_get_sid(struct proc_dir_entry *de,
1149                                 u16 tclass,
1150                                 u32 *sid)
1151 {
1152         return -EINVAL;
1153 }
1154 #endif
1155
1156 /* The inode's security attributes must be initialized before first use. */
1157 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1158 {
1159         struct superblock_security_struct *sbsec = NULL;
1160         struct inode_security_struct *isec = inode->i_security;
1161         u32 sid;
1162         struct dentry *dentry;
1163 #define INITCONTEXTLEN 255
1164         char *context = NULL;
1165         unsigned len = 0;
1166         int rc = 0;
1167
1168         if (isec->initialized)
1169                 goto out;
1170
1171         mutex_lock(&isec->lock);
1172         if (isec->initialized)
1173                 goto out_unlock;
1174
1175         sbsec = inode->i_sb->s_security;
1176         if (!sbsec->initialized) {
1177                 /* Defer initialization until selinux_complete_init,
1178                    after the initial policy is loaded and the security
1179                    server is ready to handle calls. */
1180                 spin_lock(&sbsec->isec_lock);
1181                 if (list_empty(&isec->list))
1182                         list_add(&isec->list, &sbsec->isec_head);
1183                 spin_unlock(&sbsec->isec_lock);
1184                 goto out_unlock;
1185         }
1186
1187         switch (sbsec->behavior) {
1188         case SECURITY_FS_USE_XATTR:
1189                 if (!inode->i_op->getxattr) {
1190                         isec->sid = sbsec->def_sid;
1191                         break;
1192                 }
1193
1194                 /* Need a dentry, since the xattr API requires one.
1195                    Life would be simpler if we could just pass the inode. */
1196                 if (opt_dentry) {
1197                         /* Called from d_instantiate or d_splice_alias. */
1198                         dentry = dget(opt_dentry);
1199                 } else {
1200                         /* Called from selinux_complete_init, try to find a dentry. */
1201                         dentry = d_find_alias(inode);
1202                 }
1203                 if (!dentry) {
1204                         printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1205                                "ino=%ld\n", __func__, inode->i_sb->s_id,
1206                                inode->i_ino);
1207                         goto out_unlock;
1208                 }
1209
1210                 len = INITCONTEXTLEN;
1211                 context = kmalloc(len, GFP_NOFS);
1212                 if (!context) {
1213                         rc = -ENOMEM;
1214                         dput(dentry);
1215                         goto out_unlock;
1216                 }
1217                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1218                                            context, len);
1219                 if (rc == -ERANGE) {
1220                         /* Need a larger buffer.  Query for the right size. */
1221                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1222                                                    NULL, 0);
1223                         if (rc < 0) {
1224                                 dput(dentry);
1225                                 goto out_unlock;
1226                         }
1227                         kfree(context);
1228                         len = rc;
1229                         context = kmalloc(len, GFP_NOFS);
1230                         if (!context) {
1231                                 rc = -ENOMEM;
1232                                 dput(dentry);
1233                                 goto out_unlock;
1234                         }
1235                         rc = inode->i_op->getxattr(dentry,
1236                                                    XATTR_NAME_SELINUX,
1237                                                    context, len);
1238                 }
1239                 dput(dentry);
1240                 if (rc < 0) {
1241                         if (rc != -ENODATA) {
1242                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1243                                        "%d for dev=%s ino=%ld\n", __func__,
1244                                        -rc, inode->i_sb->s_id, inode->i_ino);
1245                                 kfree(context);
1246                                 goto out_unlock;
1247                         }
1248                         /* Map ENODATA to the default file SID */
1249                         sid = sbsec->def_sid;
1250                         rc = 0;
1251                 } else {
1252                         rc = security_context_to_sid_default(context, rc, &sid,
1253                                                              sbsec->def_sid,
1254                                                              GFP_NOFS);
1255                         if (rc) {
1256                                 printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1257                                        "returned %d for dev=%s ino=%ld\n",
1258                                        __func__, context, -rc,
1259                                        inode->i_sb->s_id, inode->i_ino);
1260                                 kfree(context);
1261                                 /* Leave with the unlabeled SID */
1262                                 rc = 0;
1263                                 break;
1264                         }
1265                 }
1266                 kfree(context);
1267                 isec->sid = sid;
1268                 break;
1269         case SECURITY_FS_USE_TASK:
1270                 isec->sid = isec->task_sid;
1271                 break;
1272         case SECURITY_FS_USE_TRANS:
1273                 /* Default to the fs SID. */
1274                 isec->sid = sbsec->sid;
1275
1276                 /* Try to obtain a transition SID. */
1277                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1278                 rc = security_transition_sid(isec->task_sid,
1279                                              sbsec->sid,
1280                                              isec->sclass,
1281                                              &sid);
1282                 if (rc)
1283                         goto out_unlock;
1284                 isec->sid = sid;
1285                 break;
1286         case SECURITY_FS_USE_MNTPOINT:
1287                 isec->sid = sbsec->mntpoint_sid;
1288                 break;
1289         default:
1290                 /* Default to the fs superblock SID. */
1291                 isec->sid = sbsec->sid;
1292
1293                 if (sbsec->proc) {
1294                         struct proc_inode *proci = PROC_I(inode);
1295                         if (proci->pde) {
1296                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1297                                 rc = selinux_proc_get_sid(proci->pde,
1298                                                           isec->sclass,
1299                                                           &sid);
1300                                 if (rc)
1301                                         goto out_unlock;
1302                                 isec->sid = sid;
1303                         }
1304                 }
1305                 break;
1306         }
1307
1308         isec->initialized = 1;
1309
1310 out_unlock:
1311         mutex_unlock(&isec->lock);
1312 out:
1313         if (isec->sclass == SECCLASS_FILE)
1314                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1315         return rc;
1316 }
1317
1318 /* Convert a Linux signal to an access vector. */
1319 static inline u32 signal_to_av(int sig)
1320 {
1321         u32 perm = 0;
1322
1323         switch (sig) {
1324         case SIGCHLD:
1325                 /* Commonly granted from child to parent. */
1326                 perm = PROCESS__SIGCHLD;
1327                 break;
1328         case SIGKILL:
1329                 /* Cannot be caught or ignored */
1330                 perm = PROCESS__SIGKILL;
1331                 break;
1332         case SIGSTOP:
1333                 /* Cannot be caught or ignored */
1334                 perm = PROCESS__SIGSTOP;
1335                 break;
1336         default:
1337                 /* All other signals. */
1338                 perm = PROCESS__SIGNAL;
1339                 break;
1340         }
1341
1342         return perm;
1343 }
1344
1345 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1346    fork check, ptrace check, etc. */
1347 static int task_has_perm(struct task_struct *tsk1,
1348                          struct task_struct *tsk2,
1349                          u32 perms)
1350 {
1351         struct task_security_struct *tsec1, *tsec2;
1352
1353         tsec1 = tsk1->security;
1354         tsec2 = tsk2->security;
1355         return avc_has_perm(tsec1->sid, tsec2->sid,
1356                             SECCLASS_PROCESS, perms, NULL);
1357 }
1358
1359 #if CAP_LAST_CAP > 63
1360 #error Fix SELinux to handle capabilities > 63.
1361 #endif
1362
1363 /* Check whether a task is allowed to use a capability. */
1364 static int task_has_capability(struct task_struct *tsk,
1365                                int cap)
1366 {
1367         struct task_security_struct *tsec;
1368         struct avc_audit_data ad;
1369         u16 sclass;
1370         u32 av = CAP_TO_MASK(cap);
1371
1372         tsec = tsk->security;
1373
1374         AVC_AUDIT_DATA_INIT(&ad, CAP);
1375         ad.tsk = tsk;
1376         ad.u.cap = cap;
1377
1378         switch (CAP_TO_INDEX(cap)) {
1379         case 0:
1380                 sclass = SECCLASS_CAPABILITY;
1381                 break;
1382         case 1:
1383                 sclass = SECCLASS_CAPABILITY2;
1384                 break;
1385         default:
1386                 printk(KERN_ERR
1387                        "SELinux:  out of range capability %d\n", cap);
1388                 BUG();
1389         }
1390         return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
1391 }
1392
1393 /* Check whether a task is allowed to use a system operation. */
1394 static int task_has_system(struct task_struct *tsk,
1395                            u32 perms)
1396 {
1397         struct task_security_struct *tsec;
1398
1399         tsec = tsk->security;
1400
1401         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1402                             SECCLASS_SYSTEM, perms, NULL);
1403 }
1404
1405 /* Check whether a task has a particular permission to an inode.
1406    The 'adp' parameter is optional and allows other audit
1407    data to be passed (e.g. the dentry). */
1408 static int inode_has_perm(struct task_struct *tsk,
1409                           struct inode *inode,
1410                           u32 perms,
1411                           struct avc_audit_data *adp)
1412 {
1413         struct task_security_struct *tsec;
1414         struct inode_security_struct *isec;
1415         struct avc_audit_data ad;
1416
1417         if (unlikely(IS_PRIVATE(inode)))
1418                 return 0;
1419
1420         tsec = tsk->security;
1421         isec = inode->i_security;
1422
1423         if (!adp) {
1424                 adp = &ad;
1425                 AVC_AUDIT_DATA_INIT(&ad, FS);
1426                 ad.u.fs.inode = inode;
1427         }
1428
1429         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1430 }
1431
1432 /* Same as inode_has_perm, but pass explicit audit data containing
1433    the dentry to help the auditing code to more easily generate the
1434    pathname if needed. */
1435 static inline int dentry_has_perm(struct task_struct *tsk,
1436                                   struct vfsmount *mnt,
1437                                   struct dentry *dentry,
1438                                   u32 av)
1439 {
1440         struct inode *inode = dentry->d_inode;
1441         struct avc_audit_data ad;
1442         AVC_AUDIT_DATA_INIT(&ad, FS);
1443         ad.u.fs.path.mnt = mnt;
1444         ad.u.fs.path.dentry = dentry;
1445         return inode_has_perm(tsk, inode, av, &ad);
1446 }
1447
1448 /* Check whether a task can use an open file descriptor to
1449    access an inode in a given way.  Check access to the
1450    descriptor itself, and then use dentry_has_perm to
1451    check a particular permission to the file.
1452    Access to the descriptor is implicitly granted if it
1453    has the same SID as the process.  If av is zero, then
1454    access to the file is not checked, e.g. for cases
1455    where only the descriptor is affected like seek. */
1456 static int file_has_perm(struct task_struct *tsk,
1457                                 struct file *file,
1458                                 u32 av)
1459 {
1460         struct task_security_struct *tsec = tsk->security;
1461         struct file_security_struct *fsec = file->f_security;
1462         struct inode *inode = file->f_path.dentry->d_inode;
1463         struct avc_audit_data ad;
1464         int rc;
1465
1466         AVC_AUDIT_DATA_INIT(&ad, FS);
1467         ad.u.fs.path = file->f_path;
1468
1469         if (tsec->sid != fsec->sid) {
1470                 rc = avc_has_perm(tsec->sid, fsec->sid,
1471                                   SECCLASS_FD,
1472                                   FD__USE,
1473                                   &ad);
1474                 if (rc)
1475                         return rc;
1476         }
1477
1478         /* av is zero if only checking access to the descriptor. */
1479         if (av)
1480                 return inode_has_perm(tsk, inode, av, &ad);
1481
1482         return 0;
1483 }
1484
1485 /* Check whether a task can create a file. */
1486 static int may_create(struct inode *dir,
1487                       struct dentry *dentry,
1488                       u16 tclass)
1489 {
1490         struct task_security_struct *tsec;
1491         struct inode_security_struct *dsec;
1492         struct superblock_security_struct *sbsec;
1493         u32 newsid;
1494         struct avc_audit_data ad;
1495         int rc;
1496
1497         tsec = current->security;
1498         dsec = dir->i_security;
1499         sbsec = dir->i_sb->s_security;
1500
1501         AVC_AUDIT_DATA_INIT(&ad, FS);
1502         ad.u.fs.path.dentry = dentry;
1503
1504         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1505                           DIR__ADD_NAME | DIR__SEARCH,
1506                           &ad);
1507         if (rc)
1508                 return rc;
1509
1510         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1511                 newsid = tsec->create_sid;
1512         } else {
1513                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1514                                              &newsid);
1515                 if (rc)
1516                         return rc;
1517         }
1518
1519         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1520         if (rc)
1521                 return rc;
1522
1523         return avc_has_perm(newsid, sbsec->sid,
1524                             SECCLASS_FILESYSTEM,
1525                             FILESYSTEM__ASSOCIATE, &ad);
1526 }
1527
1528 /* Check whether a task can create a key. */
1529 static int may_create_key(u32 ksid,
1530                           struct task_struct *ctx)
1531 {
1532         struct task_security_struct *tsec;
1533
1534         tsec = ctx->security;
1535
1536         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1537 }
1538
1539 #define MAY_LINK        0
1540 #define MAY_UNLINK      1
1541 #define MAY_RMDIR       2
1542
1543 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1544 static int may_link(struct inode *dir,
1545                     struct dentry *dentry,
1546                     int kind)
1547
1548 {
1549         struct task_security_struct *tsec;
1550         struct inode_security_struct *dsec, *isec;
1551         struct avc_audit_data ad;
1552         u32 av;
1553         int rc;
1554
1555         tsec = current->security;
1556         dsec = dir->i_security;
1557         isec = dentry->d_inode->i_security;
1558
1559         AVC_AUDIT_DATA_INIT(&ad, FS);
1560         ad.u.fs.path.dentry = dentry;
1561
1562         av = DIR__SEARCH;
1563         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1564         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1565         if (rc)
1566                 return rc;
1567
1568         switch (kind) {
1569         case MAY_LINK:
1570                 av = FILE__LINK;
1571                 break;
1572         case MAY_UNLINK:
1573                 av = FILE__UNLINK;
1574                 break;
1575         case MAY_RMDIR:
1576                 av = DIR__RMDIR;
1577                 break;
1578         default:
1579                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1580                         __func__, kind);
1581                 return 0;
1582         }
1583
1584         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1585         return rc;
1586 }
1587
1588 static inline int may_rename(struct inode *old_dir,
1589                              struct dentry *old_dentry,
1590                              struct inode *new_dir,
1591                              struct dentry *new_dentry)
1592 {
1593         struct task_security_struct *tsec;
1594         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1595         struct avc_audit_data ad;
1596         u32 av;
1597         int old_is_dir, new_is_dir;
1598         int rc;
1599
1600         tsec = current->security;
1601         old_dsec = old_dir->i_security;
1602         old_isec = old_dentry->d_inode->i_security;
1603         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1604         new_dsec = new_dir->i_security;
1605
1606         AVC_AUDIT_DATA_INIT(&ad, FS);
1607
1608         ad.u.fs.path.dentry = old_dentry;
1609         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1610                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1611         if (rc)
1612                 return rc;
1613         rc = avc_has_perm(tsec->sid, old_isec->sid,
1614                           old_isec->sclass, FILE__RENAME, &ad);
1615         if (rc)
1616                 return rc;
1617         if (old_is_dir && new_dir != old_dir) {
1618                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1619                                   old_isec->sclass, DIR__REPARENT, &ad);
1620                 if (rc)
1621                         return rc;
1622         }
1623
1624         ad.u.fs.path.dentry = new_dentry;
1625         av = DIR__ADD_NAME | DIR__SEARCH;
1626         if (new_dentry->d_inode)
1627                 av |= DIR__REMOVE_NAME;
1628         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631         if (new_dentry->d_inode) {
1632                 new_isec = new_dentry->d_inode->i_security;
1633                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1634                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1635                                   new_isec->sclass,
1636                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1637                 if (rc)
1638                         return rc;
1639         }
1640
1641         return 0;
1642 }
1643
1644 /* Check whether a task can perform a filesystem operation. */
1645 static int superblock_has_perm(struct task_struct *tsk,
1646                                struct super_block *sb,
1647                                u32 perms,
1648                                struct avc_audit_data *ad)
1649 {
1650         struct task_security_struct *tsec;
1651         struct superblock_security_struct *sbsec;
1652
1653         tsec = tsk->security;
1654         sbsec = sb->s_security;
1655         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1656                             perms, ad);
1657 }
1658
1659 /* Convert a Linux mode and permission mask to an access vector. */
1660 static inline u32 file_mask_to_av(int mode, int mask)
1661 {
1662         u32 av = 0;
1663
1664         if ((mode & S_IFMT) != S_IFDIR) {
1665                 if (mask & MAY_EXEC)
1666                         av |= FILE__EXECUTE;
1667                 if (mask & MAY_READ)
1668                         av |= FILE__READ;
1669
1670                 if (mask & MAY_APPEND)
1671                         av |= FILE__APPEND;
1672                 else if (mask & MAY_WRITE)
1673                         av |= FILE__WRITE;
1674
1675         } else {
1676                 if (mask & MAY_EXEC)
1677                         av |= DIR__SEARCH;
1678                 if (mask & MAY_WRITE)
1679                         av |= DIR__WRITE;
1680                 if (mask & MAY_READ)
1681                         av |= DIR__READ;
1682         }
1683
1684         return av;
1685 }
1686
1687 /*
1688  * Convert a file mask to an access vector and include the correct open
1689  * open permission.
1690  */
1691 static inline u32 open_file_mask_to_av(int mode, int mask)
1692 {
1693         u32 av = file_mask_to_av(mode, mask);
1694
1695         if (selinux_policycap_openperm) {
1696                 /*
1697                  * lnk files and socks do not really have an 'open'
1698                  */
1699                 if (S_ISREG(mode))
1700                         av |= FILE__OPEN;
1701                 else if (S_ISCHR(mode))
1702                         av |= CHR_FILE__OPEN;
1703                 else if (S_ISBLK(mode))
1704                         av |= BLK_FILE__OPEN;
1705                 else if (S_ISFIFO(mode))
1706                         av |= FIFO_FILE__OPEN;
1707                 else if (S_ISDIR(mode))
1708                         av |= DIR__OPEN;
1709                 else
1710                         printk(KERN_ERR "SELinux: WARNING: inside %s with "
1711                                 "unknown mode:%x\n", __func__, mode);
1712         }
1713         return av;
1714 }
1715
1716 /* Convert a Linux file to an access vector. */
1717 static inline u32 file_to_av(struct file *file)
1718 {
1719         u32 av = 0;
1720
1721         if (file->f_mode & FMODE_READ)
1722                 av |= FILE__READ;
1723         if (file->f_mode & FMODE_WRITE) {
1724                 if (file->f_flags & O_APPEND)
1725                         av |= FILE__APPEND;
1726                 else
1727                         av |= FILE__WRITE;
1728         }
1729         if (!av) {
1730                 /*
1731                  * Special file opened with flags 3 for ioctl-only use.
1732                  */
1733                 av = FILE__IOCTL;
1734         }
1735
1736         return av;
1737 }
1738
1739 /* Hook functions begin here. */
1740
1741 static int selinux_ptrace(struct task_struct *parent,
1742                           struct task_struct *child,
1743                           unsigned int mode)
1744 {
1745         int rc;
1746
1747         rc = secondary_ops->ptrace(parent, child, mode);
1748         if (rc)
1749                 return rc;
1750
1751         if (mode == PTRACE_MODE_READ) {
1752                 struct task_security_struct *tsec = parent->security;
1753                 struct task_security_struct *csec = child->security;
1754                 return avc_has_perm(tsec->sid, csec->sid,
1755                                     SECCLASS_FILE, FILE__READ, NULL);
1756         }
1757
1758         return task_has_perm(parent, child, PROCESS__PTRACE);
1759 }
1760
1761 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1762                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1763 {
1764         int error;
1765
1766         error = task_has_perm(current, target, PROCESS__GETCAP);
1767         if (error)
1768                 return error;
1769
1770         return secondary_ops->capget(target, effective, inheritable, permitted);
1771 }
1772
1773 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1774                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1775 {
1776         int error;
1777
1778         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1779         if (error)
1780                 return error;
1781
1782         return task_has_perm(current, target, PROCESS__SETCAP);
1783 }
1784
1785 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1786                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1787 {
1788         secondary_ops->capset_set(target, effective, inheritable, permitted);
1789 }
1790
1791 static int selinux_capable(struct task_struct *tsk, int cap)
1792 {
1793         int rc;
1794
1795         rc = secondary_ops->capable(tsk, cap);
1796         if (rc)
1797                 return rc;
1798
1799         return task_has_capability(tsk, cap);
1800 }
1801
1802 static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
1803 {
1804         int buflen, rc;
1805         char *buffer, *path, *end;
1806
1807         rc = -ENOMEM;
1808         buffer = (char *)__get_free_page(GFP_KERNEL);
1809         if (!buffer)
1810                 goto out;
1811
1812         buflen = PAGE_SIZE;
1813         end = buffer+buflen;
1814         *--end = '\0';
1815         buflen--;
1816         path = end-1;
1817         *path = '/';
1818         while (table) {
1819                 const char *name = table->procname;
1820                 size_t namelen = strlen(name);
1821                 buflen -= namelen + 1;
1822                 if (buflen < 0)
1823                         goto out_free;
1824                 end -= namelen;
1825                 memcpy(end, name, namelen);
1826                 *--end = '/';
1827                 path = end;
1828                 table = table->parent;
1829         }
1830         buflen -= 4;
1831         if (buflen < 0)
1832                 goto out_free;
1833         end -= 4;
1834         memcpy(end, "/sys", 4);
1835         path = end;
1836         rc = security_genfs_sid("proc", path, tclass, sid);
1837 out_free:
1838         free_page((unsigned long)buffer);
1839 out:
1840         return rc;
1841 }
1842
1843 static int selinux_sysctl(ctl_table *table, int op)
1844 {
1845         int error = 0;
1846         u32 av;
1847         struct task_security_struct *tsec;
1848         u32 tsid;
1849         int rc;
1850
1851         rc = secondary_ops->sysctl(table, op);
1852         if (rc)
1853                 return rc;
1854
1855         tsec = current->security;
1856
1857         rc = selinux_sysctl_get_sid(table, (op == 0001) ?
1858                                     SECCLASS_DIR : SECCLASS_FILE, &tsid);
1859         if (rc) {
1860                 /* Default to the well-defined sysctl SID. */
1861                 tsid = SECINITSID_SYSCTL;
1862         }
1863
1864         /* The op values are "defined" in sysctl.c, thereby creating
1865          * a bad coupling between this module and sysctl.c */
1866         if (op == 001) {
1867                 error = avc_has_perm(tsec->sid, tsid,
1868                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1869         } else {
1870                 av = 0;
1871                 if (op & 004)
1872                         av |= FILE__READ;
1873                 if (op & 002)
1874                         av |= FILE__WRITE;
1875                 if (av)
1876                         error = avc_has_perm(tsec->sid, tsid,
1877                                              SECCLASS_FILE, av, NULL);
1878         }
1879
1880         return error;
1881 }
1882
1883 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1884 {
1885         int rc = 0;
1886
1887         if (!sb)
1888                 return 0;
1889
1890         switch (cmds) {
1891         case Q_SYNC:
1892         case Q_QUOTAON:
1893         case Q_QUOTAOFF:
1894         case Q_SETINFO:
1895         case Q_SETQUOTA:
1896                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,
1897                                          NULL);
1898                 break;
1899         case Q_GETFMT:
1900         case Q_GETINFO:
1901         case Q_GETQUOTA:
1902                 rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,
1903                                          NULL);
1904                 break;
1905         default:
1906                 rc = 0;  /* let the kernel handle invalid cmds */
1907                 break;
1908         }
1909         return rc;
1910 }
1911
1912 static int selinux_quota_on(struct dentry *dentry)
1913 {
1914         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1915 }
1916
1917 static int selinux_syslog(int type)
1918 {
1919         int rc;
1920
1921         rc = secondary_ops->syslog(type);
1922         if (rc)
1923                 return rc;
1924
1925         switch (type) {
1926         case 3:         /* Read last kernel messages */
1927         case 10:        /* Return size of the log buffer */
1928                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929                 break;
1930         case 6:         /* Disable logging to console */
1931         case 7:         /* Enable logging to console */
1932         case 8:         /* Set level of messages printed to console */
1933                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1934                 break;
1935         case 0:         /* Close log */
1936         case 1:         /* Open log */
1937         case 2:         /* Read from log */
1938         case 4:         /* Read/clear last kernel messages */
1939         case 5:         /* Clear ring buffer */
1940         default:
1941                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1942                 break;
1943         }
1944         return rc;
1945 }
1946
1947 /*
1948  * Check that a process has enough memory to allocate a new virtual
1949  * mapping. 0 means there is enough memory for the allocation to
1950  * succeed and -ENOMEM implies there is not.
1951  *
1952  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1953  * if the capability is granted, but __vm_enough_memory requires 1 if
1954  * the capability is granted.
1955  *
1956  * Do not audit the selinux permission check, as this is applied to all
1957  * processes that allocate mappings.
1958  */
1959 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1960 {
1961         int rc, cap_sys_admin = 0;
1962         struct task_security_struct *tsec = current->security;
1963
1964         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1965         if (rc == 0)
1966                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1967                                           SECCLASS_CAPABILITY,
1968                                           CAP_TO_MASK(CAP_SYS_ADMIN),
1969                                           0,
1970                                           NULL);
1971
1972         if (rc == 0)
1973                 cap_sys_admin = 1;
1974
1975         return __vm_enough_memory(mm, pages, cap_sys_admin);
1976 }
1977
1978 /* binprm security operations */
1979
1980 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1981 {
1982         struct bprm_security_struct *bsec;
1983
1984         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1985         if (!bsec)
1986                 return -ENOMEM;
1987
1988         bsec->sid = SECINITSID_UNLABELED;
1989         bsec->set = 0;
1990
1991         bprm->security = bsec;
1992         return 0;
1993 }
1994
1995 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1996 {
1997         struct task_security_struct *tsec;
1998         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1999         struct inode_security_struct *isec;
2000         struct bprm_security_struct *bsec;
2001         u32 newsid;
2002         struct avc_audit_data ad;
2003         int rc;
2004
2005         rc = secondary_ops->bprm_set_security(bprm);
2006         if (rc)
2007                 return rc;
2008
2009         bsec = bprm->security;
2010
2011         if (bsec->set)
2012                 return 0;
2013
2014         tsec = current->security;
2015         isec = inode->i_security;
2016
2017         /* Default to the current task SID. */
2018         bsec->sid = tsec->sid;
2019
2020         /* Reset fs, key, and sock SIDs on execve. */
2021         tsec->create_sid = 0;
2022         tsec->keycreate_sid = 0;
2023         tsec->sockcreate_sid = 0;
2024
2025         if (tsec->exec_sid) {
2026                 newsid = tsec->exec_sid;
2027                 /* Reset exec SID on execve. */
2028                 tsec->exec_sid = 0;
2029         } else {
2030                 /* Check for a default transition on this program. */
2031                 rc = security_transition_sid(tsec->sid, isec->sid,
2032                                              SECCLASS_PROCESS, &newsid);
2033                 if (rc)
2034                         return rc;
2035         }
2036
2037         AVC_AUDIT_DATA_INIT(&ad, FS);
2038         ad.u.fs.path = bprm->file->f_path;
2039
2040         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2041                 newsid = tsec->sid;
2042
2043         if (tsec->sid == newsid) {
2044                 rc = avc_has_perm(tsec->sid, isec->sid,
2045                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2046                 if (rc)
2047                         return rc;
2048         } else {
2049                 /* Check permissions for the transition. */
2050                 rc = avc_has_perm(tsec->sid, newsid,
2051                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2052                 if (rc)
2053                         return rc;
2054
2055                 rc = avc_has_perm(newsid, isec->sid,
2056                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2057                 if (rc)
2058                         return rc;
2059
2060                 /* Clear any possibly unsafe personality bits on exec: */
2061                 current->personality &= ~PER_CLEAR_ON_SETID;
2062
2063                 /* Set the security field to the new SID. */
2064                 bsec->sid = newsid;
2065         }
2066
2067         bsec->set = 1;
2068         return 0;
2069 }
2070
2071 static int selinux_bprm_check_security(struct linux_binprm *bprm)
2072 {
2073         return secondary_ops->bprm_check_security(bprm);
2074 }
2075
2076
2077 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2078 {
2079         struct task_security_struct *tsec = current->security;
2080         int atsecure = 0;
2081
2082         if (tsec->osid != tsec->sid) {
2083                 /* Enable secure mode for SIDs transitions unless
2084                    the noatsecure permission is granted between
2085                    the two SIDs, i.e. ahp returns 0. */
2086                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
2087                                          SECCLASS_PROCESS,
2088                                          PROCESS__NOATSECURE, NULL);
2089         }
2090
2091         return (atsecure || secondary_ops->bprm_secureexec(bprm));
2092 }
2093
2094 static void selinux_bprm_free_security(struct linux_binprm *bprm)
2095 {
2096         kfree(bprm->security);
2097         bprm->security = NULL;
2098 }
2099
2100 extern struct vfsmount *selinuxfs_mount;
2101 extern struct dentry *selinux_null;
2102
2103 /* Derived from fs/exec.c:flush_old_files. */
2104 static inline void flush_unauthorized_files(struct files_struct *files)
2105 {
2106         struct avc_audit_data ad;
2107         struct file *file, *devnull = NULL;
2108         struct tty_struct *tty;
2109         struct fdtable *fdt;
2110         long j = -1;
2111         int drop_tty = 0;
2112
2113         mutex_lock(&tty_mutex);
2114         tty = get_current_tty();
2115         if (tty) {
2116                 file_list_lock();
2117                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
2118                 if (file) {
2119                         /* Revalidate access to controlling tty.
2120                            Use inode_has_perm on the tty inode directly rather
2121                            than using file_has_perm, as this particular open
2122                            file may belong to another process and we are only
2123                            interested in the inode-based check here. */
2124                         struct inode *inode = file->f_path.dentry->d_inode;
2125                         if (inode_has_perm(current, inode,
2126                                            FILE__READ | FILE__WRITE, NULL)) {
2127                                 drop_tty = 1;
2128                         }
2129                 }
2130                 file_list_unlock();
2131         }
2132         mutex_unlock(&tty_mutex);
2133         /* Reset controlling tty. */
2134         if (drop_tty)
2135                 no_tty();
2136
2137         /* Revalidate access to inherited open files. */
2138
2139         AVC_AUDIT_DATA_INIT(&ad, FS);
2140
2141         spin_lock(&files->file_lock);
2142         for (;;) {
2143                 unsigned long set, i;
2144                 int fd;
2145
2146                 j++;
2147                 i = j * __NFDBITS;
2148                 fdt = files_fdtable(files);
2149                 if (i >= fdt->max_fds)
2150                         break;
2151                 set = fdt->open_fds->fds_bits[j];
2152                 if (!set)
2153                         continue;
2154                 spin_unlock(&files->file_lock);
2155                 for ( ; set ; i++, set >>= 1) {
2156                         if (set & 1) {
2157                                 file = fget(i);
2158                                 if (!file)
2159                                         continue;
2160                                 if (file_has_perm(current,
2161                                                   file,
2162                                                   file_to_av(file))) {
2163                                         sys_close(i);
2164                                         fd = get_unused_fd();
2165                                         if (fd != i) {
2166                                                 if (fd >= 0)
2167                                                         put_unused_fd(fd);
2168                                                 fput(file);
2169                                                 continue;
2170                                         }
2171                                         if (devnull) {
2172                                                 get_file(devnull);
2173                                         } else {
2174                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
2175                                                 if (IS_ERR(devnull)) {
2176                                                         devnull = NULL;
2177                                                         put_unused_fd(fd);
2178                                                         fput(file);
2179                                                         continue;
2180                                                 }
2181                                         }
2182                                         fd_install(fd, devnull);
2183                                 }
2184                                 fput(file);
2185                         }
2186                 }
2187                 spin_lock(&files->file_lock);
2188
2189         }
2190         spin_unlock(&files->file_lock);
2191 }
2192
2193 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
2194 {
2195         struct task_security_struct *tsec;
2196         struct bprm_security_struct *bsec;
2197         u32 sid;
2198         int rc;
2199
2200         secondary_ops->bprm_apply_creds(bprm, unsafe);
2201
2202         tsec = current->security;
2203
2204         bsec = bprm->security;
2205         sid = bsec->sid;
2206
2207         tsec->osid = tsec->sid;
2208         bsec->unsafe = 0;
2209         if (tsec->sid != sid) {
2210                 /* Check for shared state.  If not ok, leave SID
2211                    unchanged and kill. */
2212                 if (unsafe & LSM_UNSAFE_SHARE) {
2213                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
2214                                         PROCESS__SHARE, NULL);
2215                         if (rc) {
2216                                 bsec->unsafe = 1;
2217                                 return;
2218                         }
2219                 }
2220
2221                 /* Check for ptracing, and update the task SID if ok.
2222                    Otherwise, leave SID unchanged and kill. */
2223                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2224                         struct task_struct *tracer;
2225                         struct task_security_struct *sec;
2226                         u32 ptsid = 0;
2227
2228                         rcu_read_lock();
2229                         tracer = tracehook_tracer_task(current);
2230                         if (likely(tracer != NULL)) {
2231                                 sec = tracer->security;
2232                                 ptsid = sec->sid;
2233                         }
2234                         rcu_read_unlock();
2235
2236                         if (ptsid != 0) {
2237                                 rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
2238                                                   PROCESS__PTRACE, NULL);
2239                                 if (rc) {
2240                                         bsec->unsafe = 1;
2241                                         return;
2242                                 }
2243                         }
2244                 }
2245                 tsec->sid = sid;
2246         }
2247 }
2248
2249 /*
2250  * called after apply_creds without the task lock held
2251  */
2252 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
2253 {
2254         struct task_security_struct *tsec;
2255         struct rlimit *rlim, *initrlim;
2256         struct itimerval itimer;
2257         struct bprm_security_struct *bsec;
2258         int rc, i;
2259
2260         tsec = current->security;
2261         bsec = bprm->security;
2262
2263         if (bsec->unsafe) {
2264                 force_sig_specific(SIGKILL, current);
2265                 return;
2266         }
2267         if (tsec->osid == tsec->sid)
2268                 return;
2269
2270         /* Close files for which the new task SID is not authorized. */
2271         flush_unauthorized_files(current->files);
2272
2273         /* Check whether the new SID can inherit signal state
2274            from the old SID.  If not, clear itimers to avoid
2275            subsequent signal generation and flush and unblock
2276            signals. This must occur _after_ the task SID has
2277           been updated so that any kill done after the flush
2278           will be checked against the new SID. */
2279         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2280                           PROCESS__SIGINH, NULL);
2281         if (rc) {
2282                 memset(&itimer, 0, sizeof itimer);
2283                 for (i = 0; i < 3; i++)
2284                         do_setitimer(i, &itimer, NULL);
2285                 flush_signals(current);
2286                 spin_lock_irq(&current->sighand->siglock);
2287                 flush_signal_handlers(current, 1);
2288                 sigemptyset(&current->blocked);
2289                 recalc_sigpending();
2290                 spin_unlock_irq(&current->sighand->siglock);
2291         }
2292
2293         /* Always clear parent death signal on SID transitions. */
2294         current->pdeath_signal = 0;
2295
2296         /* Check whether the new SID can inherit resource limits
2297            from the old SID.  If not, reset all soft limits to
2298            the lower of the current task's hard limit and the init
2299            task's soft limit.  Note that the setting of hard limits
2300            (even to lower them) can be controlled by the setrlimit
2301            check. The inclusion of the init task's soft limit into
2302            the computation is to avoid resetting soft limits higher
2303            than the default soft limit for cases where the default
2304            is lower than the hard limit, e.g. RLIMIT_CORE or
2305            RLIMIT_STACK.*/
2306         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
2307                           PROCESS__RLIMITINH, NULL);
2308         if (rc) {
2309                 for (i = 0; i < RLIM_NLIMITS; i++) {
2310                         rlim = current->signal->rlim + i;
2311                         initrlim = init_task.signal->rlim+i;
2312                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2313                 }
2314                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
2315                         /*
2316                          * This will cause RLIMIT_CPU calculations
2317                          * to be refigured.
2318                          */
2319                         current->it_prof_expires = jiffies_to_cputime(1);
2320                 }
2321         }
2322
2323         /* Wake up the parent if it is waiting so that it can
2324            recheck wait permission to the new task SID. */
2325         wake_up_interruptible(&current->parent->signal->wait_chldexit);
2326 }
2327
2328 /* superblock security operations */
2329
2330 static int selinux_sb_alloc_security(struct super_block *sb)
2331 {
2332         return superblock_alloc_security(sb);
2333 }
2334
2335 static void selinux_sb_free_security(struct super_block *sb)
2336 {
2337         superblock_free_security(sb);
2338 }
2339
2340 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2341 {
2342         if (plen > olen)
2343                 return 0;
2344
2345         return !memcmp(prefix, option, plen);
2346 }
2347
2348 static inline int selinux_option(char *option, int len)
2349 {
2350         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2351                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2352                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2353                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
2354 }
2355
2356 static inline void take_option(char **to, char *from, int *first, int len)
2357 {
2358         if (!*first) {
2359                 **to = ',';
2360                 *to += 1;
2361         } else
2362                 *first = 0;
2363         memcpy(*to, from, len);
2364         *to += len;
2365 }
2366
2367 static inline void take_selinux_option(char **to, char *from, int *first,
2368                                        int len)
2369 {
2370         int current_size = 0;
2371
2372         if (!*first) {
2373                 **to = '|';
2374                 *to += 1;
2375         } else
2376                 *first = 0;
2377
2378         while (current_size < len) {
2379                 if (*from != '"') {
2380                         **to = *from;
2381                         *to += 1;
2382                 }
2383                 from += 1;
2384                 current_size += 1;
2385         }
2386 }
2387
2388 static int selinux_sb_copy_data(char *orig, char *copy)
2389 {
2390         int fnosec, fsec, rc = 0;
2391         char *in_save, *in_curr, *in_end;
2392         char *sec_curr, *nosec_save, *nosec;
2393         int open_quote = 0;
2394
2395         in_curr = orig;
2396         sec_curr = copy;
2397
2398         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2399         if (!nosec) {
2400                 rc = -ENOMEM;
2401                 goto out;
2402         }
2403
2404         nosec_save = nosec;
2405         fnosec = fsec = 1;
2406         in_save = in_end = orig;
2407
2408         do {
2409                 if (*in_end == '"')
2410                         open_quote = !open_quote;
2411                 if ((*in_end == ',' && open_quote == 0) ||
2412                                 *in_end == '\0') {
2413                         int len = in_end - in_curr;
2414
2415                         if (selinux_option(in_curr, len))
2416                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2417                         else
2418                                 take_option(&nosec, in_curr, &fnosec, len);
2419
2420                         in_curr = in_end + 1;
2421                 }
2422         } while (*in_end++);
2423
2424         strcpy(in_save, nosec_save);
2425         free_page((unsigned long)nosec_save);
2426 out:
2427         return rc;
2428 }
2429
2430 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2431 {
2432         struct avc_audit_data ad;
2433         int rc;
2434
2435         rc = superblock_doinit(sb, data);
2436         if (rc)
2437                 return rc;
2438
2439         AVC_AUDIT_DATA_INIT(&ad, FS);
2440         ad.u.fs.path.dentry = sb->s_root;
2441         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2442 }
2443
2444 static int selinux_sb_statfs(struct dentry *dentry)
2445 {
2446         struct avc_audit_data ad;
2447
2448         AVC_AUDIT_DATA_INIT(&ad, FS);
2449         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2450         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2451 }
2452
2453 static int selinux_mount(char *dev_name,
2454                          struct path *path,
2455                          char *type,
2456                          unsigned long flags,
2457                          void *data)
2458 {
2459         int rc;
2460
2461         rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
2462         if (rc)
2463                 return rc;
2464
2465         if (flags & MS_REMOUNT)
2466                 return superblock_has_perm(current, path->mnt->mnt_sb,
2467                                            FILESYSTEM__REMOUNT, NULL);
2468         else
2469                 return dentry_has_perm(current, path->mnt, path->dentry,
2470                                        FILE__MOUNTON);
2471 }
2472
2473 static int selinux_umount(struct vfsmount *mnt, int flags)
2474 {
2475         int rc;
2476
2477         rc = secondary_ops->sb_umount(mnt, flags);
2478         if (rc)
2479                 return rc;
2480
2481         return superblock_has_perm(current, mnt->mnt_sb,
2482                                    FILESYSTEM__UNMOUNT, NULL);
2483 }
2484
2485 /* inode security operations */
2486
2487 static int selinux_inode_alloc_security(struct inode *inode)
2488 {
2489         return inode_alloc_security(inode);
2490 }
2491
2492 static void selinux_inode_free_security(struct inode *inode)
2493 {
2494         inode_free_security(inode);
2495 }
2496
2497 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2498                                        char **name, void **value,
2499                                        size_t *len)
2500 {
2501         struct task_security_struct *tsec;
2502         struct inode_security_struct *dsec;
2503         struct superblock_security_struct *sbsec;
2504         u32 newsid, clen;
2505         int rc;
2506         char *namep = NULL, *context;
2507
2508         tsec = current->security;
2509         dsec = dir->i_security;
2510         sbsec = dir->i_sb->s_security;
2511
2512         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2513                 newsid = tsec->create_sid;
2514         } else {
2515                 rc = security_transition_sid(tsec->sid, dsec->sid,
2516                                              inode_mode_to_security_class(inode->i_mode),
2517                                              &newsid);
2518                 if (rc) {
2519                         printk(KERN_WARNING "%s:  "
2520                                "security_transition_sid failed, rc=%d (dev=%s "
2521                                "ino=%ld)\n",
2522                                __func__,
2523                                -rc, inode->i_sb->s_id, inode->i_ino);
2524                         return rc;
2525                 }
2526         }
2527
2528         /* Possibly defer initialization to selinux_complete_init. */
2529         if (sbsec->initialized) {
2530                 struct inode_security_struct *isec = inode->i_security;
2531                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2532                 isec->sid = newsid;
2533                 isec->initialized = 1;
2534         }
2535
2536         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2537                 return -EOPNOTSUPP;
2538
2539         if (name) {
2540                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2541                 if (!namep)
2542                         return -ENOMEM;
2543                 *name = namep;
2544         }
2545
2546         if (value && len) {
2547                 rc = security_sid_to_context_force(newsid, &context, &clen);
2548                 if (rc) {
2549                         kfree(namep);
2550                         return rc;
2551                 }
2552                 *value = context;
2553                 *len = clen;
2554         }
2555
2556         return 0;
2557 }
2558
2559 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2560 {
2561         return may_create(dir, dentry, SECCLASS_FILE);
2562 }
2563
2564 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2565 {
2566         int rc;
2567
2568         rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
2569         if (rc)
2570                 return rc;
2571         return may_link(dir, old_dentry, MAY_LINK);
2572 }
2573
2574 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2575 {
2576         int rc;
2577
2578         rc = secondary_ops->inode_unlink(dir, dentry);
2579         if (rc)
2580                 return rc;
2581         return may_link(dir, dentry, MAY_UNLINK);
2582 }
2583
2584 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2585 {
2586         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2587 }
2588
2589 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2590 {
2591         return may_create(dir, dentry, SECCLASS_DIR);
2592 }
2593
2594 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2595 {
2596         return may_link(dir, dentry, MAY_RMDIR);
2597 }
2598
2599 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2600 {
2601         int rc;
2602
2603         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2604         if (rc)
2605                 return rc;
2606
2607         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2608 }
2609
2610 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2611                                 struct inode *new_inode, struct dentry *new_dentry)
2612 {
2613         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2614 }
2615
2616 static int selinux_inode_readlink(struct dentry *dentry)
2617 {
2618         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2619 }
2620
2621 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2622 {
2623         int rc;
2624
2625         rc = secondary_ops->inode_follow_link(dentry, nameidata);
2626         if (rc)
2627                 return rc;
2628         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2629 }
2630
2631 static int selinux_inode_permission(struct inode *inode, int mask)
2632 {
2633         int rc;
2634
2635         rc = secondary_ops->inode_permission(inode, mask);
2636         if (rc)
2637                 return rc;
2638
2639         if (!mask) {
2640                 /* No permission to check.  Existence test. */
2641                 return 0;
2642         }
2643
2644         return inode_has_perm(current, inode,
2645                                open_file_mask_to_av(inode->i_mode, mask), NULL);
2646 }
2647
2648 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2649 {
2650         int rc;
2651
2652         rc = secondary_ops->inode_setattr(dentry, iattr);
2653         if (rc)
2654                 return rc;
2655
2656         if (iattr->ia_valid & ATTR_FORCE)
2657                 return 0;
2658
2659         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2660                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2661                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2662
2663         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2664 }
2665
2666 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2667 {
2668         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2669 }
2670
2671 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2672 {
2673         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2674                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2675                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2676                         if (!capable(CAP_SETFCAP))
2677                                 return -EPERM;
2678                 } else if (!capable(CAP_SYS_ADMIN)) {
2679                         /* A different attribute in the security namespace.
2680                            Restrict to administrator. */
2681                         return -EPERM;
2682                 }
2683         }
2684
2685         /* Not an attribute we recognize, so just check the
2686            ordinary setattr permission. */
2687         return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2688 }
2689
2690 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2691                                   const void *value, size_t size, int flags)
2692 {
2693         struct task_security_struct *tsec = current->security;
2694         struct inode *inode = dentry->d_inode;
2695         struct inode_security_struct *isec = inode->i_security;
2696         struct superblock_security_struct *sbsec;
2697         struct avc_audit_data ad;
2698         u32 newsid;
2699         int rc = 0;
2700
2701         if (strcmp(name, XATTR_NAME_SELINUX))
2702                 return selinux_inode_setotherxattr(dentry, name);
2703
2704         sbsec = inode->i_sb->s_security;
2705         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2706                 return -EOPNOTSUPP;
2707
2708         if (!is_owner_or_cap(inode))
2709                 return -EPERM;
2710
2711         AVC_AUDIT_DATA_INIT(&ad, FS);
2712         ad.u.fs.path.dentry = dentry;
2713
2714         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2715                           FILE__RELABELFROM, &ad);
2716         if (rc)
2717                 return rc;
2718
2719         rc = security_context_to_sid(value, size, &newsid);
2720         if (rc == -EINVAL) {
2721                 if (!capable(CAP_MAC_ADMIN))
2722                         return rc;
2723                 rc = security_context_to_sid_force(value, size, &newsid);
2724         }
2725         if (rc)
2726                 return rc;
2727
2728         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2729                           FILE__RELABELTO, &ad);
2730         if (rc)
2731                 return rc;
2732
2733         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2734                                           isec->sclass);
2735         if (rc)
2736                 return rc;
2737
2738         return avc_has_perm(newsid,
2739                             sbsec->sid,
2740                             SECCLASS_FILESYSTEM,
2741                             FILESYSTEM__ASSOCIATE,
2742                             &ad);
2743 }
2744
2745 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2746                                         const void *value, size_t size,
2747                                         int flags)
2748 {
2749         struct inode *inode = dentry->d_inode;
2750         struct inode_security_struct *isec = inode->i_security;
2751         u32 newsid;
2752         int rc;
2753
2754         if (strcmp(name, XATTR_NAME_SELINUX)) {
2755                 /* Not an attribute we recognize, so nothing to do. */
2756                 return;
2757         }
2758
2759         rc = security_context_to_sid_force(value, size, &newsid);
2760         if (rc) {
2761                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2762                        "for (%s, %lu), rc=%d\n",
2763                        inode->i_sb->s_id, inode->i_ino, -rc);
2764                 return;
2765         }
2766
2767         isec->sid = newsid;
2768         return;
2769 }
2770
2771 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2772 {
2773         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2774 }
2775
2776 static int selinux_inode_listxattr(struct dentry *dentry)
2777 {
2778         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2779 }
2780
2781 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2782 {
2783         if (strcmp(name, XATTR_NAME_SELINUX))
2784                 return selinux_inode_setotherxattr(dentry, name);
2785
2786         /* No one is allowed to remove a SELinux security label.
2787            You can change the label, but all data must be labeled. */
2788         return -EACCES;
2789 }
2790
2791 /*
2792  * Copy the inode security context value to the user.
2793  *
2794  * Permission check is handled by selinux_inode_getxattr hook.
2795  */
2796 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2797 {
2798         u32 size;
2799         int error;
2800         char *context = NULL;
2801         struct task_security_struct *tsec = current->security;
2802         struct inode_security_struct *isec = inode->i_security;
2803
2804         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2805                 return -EOPNOTSUPP;
2806
2807         /*
2808          * If the caller has CAP_MAC_ADMIN, then get the raw context
2809          * value even if it is not defined by current policy; otherwise,
2810          * use the in-core value under current policy.
2811          * Use the non-auditing forms of the permission checks since
2812          * getxattr may be called by unprivileged processes commonly
2813          * and lack of permission just means that we fall back to the
2814          * in-core context value, not a denial.
2815          */
2816         error = secondary_ops->capable(current, CAP_MAC_ADMIN);
2817         if (!error)
2818                 error = avc_has_perm_noaudit(tsec->sid, tsec->sid,
2819                                              SECCLASS_CAPABILITY2,
2820                                              CAPABILITY2__MAC_ADMIN,
2821                                              0,
2822                                              NULL);
2823         if (!error)
2824                 error = security_sid_to_context_force(isec->sid, &context,
2825                                                       &size);
2826         else
2827                 error = security_sid_to_context(isec->sid, &context, &size);
2828         if (error)
2829                 return error;
2830         error = size;
2831         if (alloc) {
2832                 *buffer = context;
2833                 goto out_nofree;
2834         }
2835         kfree(context);
2836 out_nofree:
2837         return error;
2838 }
2839
2840 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2841                                      const void *value, size_t size, int flags)
2842 {
2843         struct inode_security_struct *isec = inode->i_security;
2844         u32 newsid;
2845         int rc;
2846
2847         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2848                 return -EOPNOTSUPP;
2849
2850         if (!value || !size)
2851                 return -EACCES;
2852
2853         rc = security_context_to_sid((void *)value, size, &newsid);
2854         if (rc)
2855                 return rc;
2856
2857         isec->sid = newsid;
2858         return 0;
2859 }
2860
2861 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2862 {
2863         const int len = sizeof(XATTR_NAME_SELINUX);
2864         if (buffer && len <= buffer_size)
2865                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2866         return len;
2867 }
2868
2869 static int selinux_inode_need_killpriv(struct dentry *dentry)
2870 {
2871         return secondary_ops->inode_need_killpriv(dentry);
2872 }
2873
2874 static int selinux_inode_killpriv(struct dentry *dentry)
2875 {
2876         return secondary_ops->inode_killpriv(dentry);
2877 }
2878
2879 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2880 {
2881         struct inode_security_struct *isec = inode->i_security;
2882         *secid = isec->sid;
2883 }
2884
2885 /* file security operations */
2886
2887 static int selinux_revalidate_file_permission(struct file *file, int mask)
2888 {
2889         int rc;
2890         struct inode *inode = file->f_path.dentry->d_inode;
2891
2892         if (!mask) {
2893                 /* No permission to check.  Existence test. */
2894                 return 0;
2895         }
2896
2897         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2898         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2899                 mask |= MAY_APPEND;
2900
2901         rc = file_has_perm(current, file,
2902                            file_mask_to_av(inode->i_mode, mask));
2903         if (rc)
2904                 return rc;
2905
2906         return selinux_netlbl_inode_permission(inode, mask);
2907 }
2908
2909 static int selinux_file_permission(struct file *file, int mask)
2910 {
2911         struct inode *inode = file->f_path.dentry->d_inode;
2912         struct task_security_struct *tsec = current->security;
2913         struct file_security_struct *fsec = file->f_security;
2914         struct inode_security_struct *isec = inode->i_security;
2915
2916         if (!mask) {
2917                 /* No permission to check.  Existence test. */
2918                 return 0;
2919         }
2920
2921         if (tsec->sid == fsec->sid && fsec->isid == isec->sid
2922             && fsec->pseqno == avc_policy_seqno())
2923                 return selinux_netlbl_inode_permission(inode, mask);
2924
2925         return selinux_revalidate_file_permission(file, mask);
2926 }
2927
2928 static int selinux_file_alloc_security(struct file *file)
2929 {
2930         return file_alloc_security(file);
2931 }
2932
2933 static void selinux_file_free_security(struct file *file)
2934 {
2935         file_free_security(file);
2936 }
2937
2938 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2939                               unsigned long arg)
2940 {
2941         u32 av = 0;
2942
2943         if (_IOC_DIR(cmd) & _IOC_WRITE)
2944                 av |= FILE__WRITE;
2945         if (_IOC_DIR(cmd) & _IOC_READ)
2946                 av |= FILE__READ;
2947         if (!av)
2948                 av = FILE__IOCTL;
2949
2950         return file_has_perm(current, file, av);
2951 }
2952
2953 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2954 {
2955 #ifndef CONFIG_PPC32
2956         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2957                 /*
2958                  * We are making executable an anonymous mapping or a
2959                  * private file mapping that will also be writable.
2960                  * This has an additional check.
2961                  */
2962                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2963                 if (rc)
2964                         return rc;
2965         }
2966 #endif
2967
2968         if (file) {
2969                 /* read access is always possible with a mapping */
2970                 u32 av = FILE__READ;
2971
2972                 /* write access only matters if the mapping is shared */
2973                 if (shared && (prot & PROT_WRITE))
2974                         av |= FILE__WRITE;
2975
2976                 if (prot & PROT_EXEC)
2977                         av |= FILE__EXECUTE;
2978
2979                 return file_has_perm(current, file, av);
2980         }
2981         return 0;
2982 }
2983
2984 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2985                              unsigned long prot, unsigned long flags,
2986                              unsigned long addr, unsigned long addr_only)
2987 {
2988         int rc = 0;
2989         u32 sid = ((struct task_security_struct *)(current->security))->sid;
2990
2991         if (addr < mmap_min_addr)
2992                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
2993                                   MEMPROTECT__MMAP_ZERO, NULL);
2994         if (rc || addr_only)
2995                 return rc;
2996
2997         if (selinux_checkreqprot)
2998                 prot = reqprot;
2999
3000         return file_map_prot_check(file, prot,
3001                                    (flags & MAP_TYPE) == MAP_SHARED);
3002 }
3003
3004 static int selinux_file_mprotect(struct vm_area_struct *vma,
3005                                  unsigned long reqprot,
3006                                  unsigned long prot)
3007 {
3008         int rc;
3009
3010         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
3011         if (rc)
3012                 return rc;
3013
3014         if (selinux_checkreqprot)
3015                 prot = reqprot;
3016
3017 #ifndef CONFIG_PPC32
3018         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3019                 rc = 0;
3020                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3021                     vma->vm_end <= vma->vm_mm->brk) {
3022                         rc = task_has_perm(current, current,
3023                                            PROCESS__EXECHEAP);
3024                 } else if (!vma->vm_file &&
3025                            vma->vm_start <= vma->vm_mm->start_stack &&
3026                            vma->vm_end >= vma->vm_mm->start_stack) {
3027                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
3028                 } else if (vma->vm_file && vma->anon_vma) {
3029                         /*
3030                          * We are making executable a file mapping that has
3031                          * had some COW done. Since pages might have been
3032                          * written, check ability to execute the possibly
3033                          * modified content.  This typically should only
3034                          * occur for text relocations.
3035                          */
3036                         rc = file_has_perm(current, vma->vm_file,
3037                                            FILE__EXECMOD);
3038                 }
3039                 if (rc)
3040                         return rc;
3041         }
3042 #endif
3043
3044         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3045 }
3046
3047 static int selinux_file_lock(struct file *file, unsigned int cmd)
3048 {
3049         return file_has_perm(current, file, FILE__LOCK);
3050 }
3051
3052 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3053                               unsigned long arg)
3054 {
3055         int err = 0;
3056
3057         switch (cmd) {
3058         case F_SETFL:
3059                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3060                         err = -EINVAL;
3061                         break;
3062                 }
3063
3064                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3065                         err = file_has_perm(current, file, FILE__WRITE);
3066                         break;
3067                 }
3068                 /* fall through */
3069         case F_SETOWN:
3070         case F_SETSIG:
3071         case F_GETFL:
3072         case F_GETOWN:
3073         case F_GETSIG:
3074                 /* Just check FD__USE permission */
3075                 err = file_has_perm(current, file, 0);
3076                 break;
3077         case F_GETLK:
3078         case F_SETLK:
3079         case F_SETLKW:
3080 #if BITS_PER_LONG == 32
3081         case F_GETLK64:
3082         case F_SETLK64:
3083         case F_SETLKW64:
3084 #endif
3085                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3086                         err = -EINVAL;
3087                         break;
3088                 }
3089                 err = file_has_perm(current, file, FILE__LOCK);
3090                 break;
3091         }
3092
3093         return err;
3094 }
3095
3096 static int selinux_file_set_fowner(struct file *file)
3097 {
3098         struct task_security_struct *tsec;
3099         struct file_security_struct *fsec;
3100
3101         tsec = current->security;
3102         fsec = file->f_security;
3103         fsec->fown_sid = tsec->sid;
3104
3105         return 0;
3106 }
3107
3108 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3109                                        struct fown_struct *fown, int signum)
3110 {
3111         struct file *file;
3112         u32 perm;
3113         struct task_security_struct *tsec;
3114         struct file_security_struct *fsec;
3115
3116         /* struct fown_struct is never outside the context of a struct file */
3117         file = container_of(fown, struct file, f_owner);
3118
3119         tsec = tsk->security;
3120         fsec = file->f_security;
3121
3122         if (!signum)
3123                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3124         else
3125                 perm = signal_to_av(signum);
3126
3127         return avc_has_perm(fsec->fown_sid, tsec->sid,
3128                             SECCLASS_PROCESS, perm, NULL);
3129 }
3130
3131 static int selinux_file_receive(struct file *file)
3132 {
3133         return file_has_perm(current, file, file_to_av(file));
3134 }
3135
3136 static int selinux_dentry_open(struct file *file)
3137 {
3138         struct file_security_struct *fsec;
3139         struct inode *inode;
3140         struct inode_security_struct *isec;
3141         inode = file->f_path.dentry->d_inode;
3142         fsec = file->f_security;
3143         isec = inode->i_security;
3144         /*
3145          * Save inode label and policy sequence number
3146          * at open-time so that selinux_file_permission
3147          * can determine whether revalidation is necessary.
3148          * Task label is already saved in the file security
3149          * struct as its SID.
3150          */
3151         fsec->isid = isec->sid;
3152         fsec->pseqno = avc_policy_seqno();
3153         /*
3154          * Since the inode label or policy seqno may have changed
3155          * between the selinux_inode_permission check and the saving
3156          * of state above, recheck that access is still permitted.
3157          * Otherwise, access might never be revalidated against the
3158          * new inode label or new policy.
3159          * This check is not redundant - do not remove.
3160          */
3161         return inode_has_perm(current, inode, file_to_av(file), NULL);
3162 }
3163
3164 /* task security operations */
3165
3166 static int selinux_task_create(unsigned long clone_flags)
3167 {
3168         int rc;
3169
3170         rc = secondary_ops->task_create(clone_flags);
3171         if (rc)
3172                 return rc;
3173
3174         return task_has_perm(current, current, PROCESS__FORK);
3175 }
3176
3177 static int selinux_task_alloc_security(struct task_struct *tsk)
3178 {
3179         struct task_security_struct *tsec1, *tsec2;
3180         int rc;
3181
3182         tsec1 = current->security;
3183
3184         rc = task_alloc_security(tsk);
3185         if (rc)
3186                 return rc;
3187         tsec2 = tsk->security;
3188
3189         tsec2->osid = tsec1->osid;
3190         tsec2->sid = tsec1->sid;
3191
3192         /* Retain the exec, fs, key, and sock SIDs across fork */
3193         tsec2->exec_sid = tsec1->exec_sid;
3194         tsec2->create_sid = tsec1->create_sid;
3195         tsec2->keycreate_sid = tsec1->keycreate_sid;
3196         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
3197
3198         return 0;
3199 }
3200
3201 static void selinux_task_free_security(struct task_struct *tsk)
3202 {
3203         task_free_security(tsk);
3204 }
3205
3206 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3207 {
3208         /* Since setuid only affects the current process, and
3209            since the SELinux controls are not based on the Linux
3210            identity attributes, SELinux does not need to control
3211            this operation.  However, SELinux does control the use
3212            of the CAP_SETUID and CAP_SETGID capabilities using the
3213            capable hook. */
3214         return 0;
3215 }
3216
3217 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
3218 {
3219         return secondary_ops->task_post_setuid(id0, id1, id2, flags);
3220 }
3221
3222 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
3223 {
3224         /* See the comment for setuid above. */
3225         return 0;
3226 }
3227
3228 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3229 {
3230         return task_has_perm(current, p, PROCESS__SETPGID);
3231 }
3232
3233 static int selinux_task_getpgid(struct task_struct *p)
3234 {
3235         return task_has_perm(current, p, PROCESS__GETPGID);
3236 }
3237
3238 static int selinux_task_getsid(struct task_struct *p)
3239 {
3240         return task_has_perm(current, p, PROCESS__GETSESSION);
3241 }
3242
3243 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3244 {
3245         struct task_security_struct *tsec = p->security;
3246         *secid = tsec->sid;
3247 }
3248
3249 static int selinux_task_setgroups(struct group_info *group_info)
3250 {
3251         /* See the comment for setuid above. */
3252         return 0;
3253 }
3254
3255 static int selinux_task_setnice(struct task_struct *p, int nice)
3256 {
3257         int rc;
3258
3259         rc = secondary_ops->task_setnice(p, nice);
3260         if (rc)
3261                 return rc;
3262
3263         return task_has_perm(current, p, PROCESS__SETSCHED);
3264 }
3265
3266 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3267 {
3268         int rc;
3269
3270         rc = secondary_ops->task_setioprio(p, ioprio);
3271         if (rc)
3272                 return rc;
3273
3274         return task_has_perm(current, p, PROCESS__SETSCHED);
3275 }
3276
3277 static int selinux_task_getioprio(struct task_struct *p)
3278 {
3279         return task_has_perm(current, p, PROCESS__GETSCHED);
3280 }
3281
3282 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
3283 {
3284         struct rlimit *old_rlim = current->signal->rlim + resource;
3285         int rc;
3286
3287         rc = secondary_ops->task_setrlimit(resource, new_rlim);
3288         if (rc)
3289                 return rc;
3290
3291         /* Control the ability to change the hard limit (whether
3292            lowering or raising it), so that the hard limit can
3293            later be used as a safe reset point for the soft limit
3294            upon context transitions. See selinux_bprm_apply_creds. */
3295         if (old_rlim->rlim_max != new_rlim->rlim_max)
3296                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
3297
3298         return 0;
3299 }
3300
3301 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
3302 {
3303         int rc;
3304
3305         rc = secondary_ops->task_setscheduler(p, policy, lp);
3306         if (rc)
3307                 return rc;
3308
3309         return task_has_perm(current, p, PROCESS__SETSCHED);
3310 }
3311
3312 static int selinux_task_getscheduler(struct task_struct *p)
3313 {
3314         return task_has_perm(current, p, PROCESS__GETSCHED);
3315 }
3316
3317 static int selinux_task_movememory(struct task_struct *p)
3318 {
3319         return task_has_perm(current, p, PROCESS__SETSCHED);
3320 }
3321
3322 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3323                                 int sig, u32 secid)
3324 {
3325         u32 perm;
3326         int rc;
3327         struct task_security_struct *tsec;
3328
3329         rc = secondary_ops->task_kill(p, info, sig, secid);
3330         if (rc)
3331                 return rc;
3332
3333         if (!sig)
3334                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3335         else
3336                 perm = signal_to_av(sig);
3337         tsec = p->security;
3338         if (secid)
3339                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
3340         else
3341                 rc = task_has_perm(current, p, perm);
3342         return rc;
3343 }
3344
3345 static int selinux_task_prctl(int option,
3346                               unsigned long arg2,
3347                               unsigned long arg3,
3348                               unsigned long arg4,
3349                               unsigned long arg5,
3350                               long *rc_p)
3351 {
3352         /* The current prctl operations do not appear to require
3353            any SELinux controls since they merely observe or modify
3354            the state of the current process. */
3355         return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
3356 }
3357
3358 static int selinux_task_wait(struct task_struct *p)
3359 {
3360         return task_has_perm(p, current, PROCESS__SIGCHLD);
3361 }
3362
3363 static void selinux_task_reparent_to_init(struct task_struct *p)
3364 {
3365         struct task_security_struct *tsec;
3366
3367         secondary_ops->task_reparent_to_init(p);
3368
3369         tsec = p->security;
3370         tsec->osid = tsec->sid;
3371         tsec->sid = SECINITSID_KERNEL;
3372         return;
3373 }
3374
3375 static void selinux_task_to_inode(struct task_struct *p,
3376                                   struct inode *inode)
3377 {
3378         struct task_security_struct *tsec = p->security;
3379         struct inode_security_struct *isec = inode->i_security;
3380
3381         isec->sid = tsec->sid;
3382         isec->initialized = 1;
3383         return;
3384 }
3385
3386 /* Returns error only if unable to parse addresses */
3387 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3388                         struct avc_audit_data *ad, u8 *proto)
3389 {
3390         int offset, ihlen, ret = -EINVAL;
3391         struct iphdr _iph, *ih;
3392
3393         offset = skb_network_offset(skb);
3394         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3395         if (ih == NULL)
3396                 goto out;
3397
3398         ihlen = ih->ihl * 4;
3399         if (ihlen < sizeof(_iph))
3400                 goto out;
3401
3402         ad->u.net.v4info.saddr = ih->saddr;
3403         ad->u.net.v4info.daddr = ih->daddr;
3404         ret = 0;
3405
3406         if (proto)
3407                 *proto = ih->protocol;
3408
3409         switch (ih->protocol) {
3410         case IPPROTO_TCP: {
3411                 struct tcphdr _tcph, *th;
3412
3413                 if (ntohs(ih->frag_off) & IP_OFFSET)
3414                         break;
3415
3416                 offset += ihlen;
3417                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3418                 if (th == NULL)
3419                         break;
3420
3421                 ad->u.net.sport = th->source;
3422                 ad->u.net.dport = th->dest;
3423                 break;
3424         }
3425
3426         case IPPROTO_UDP: {
3427                 struct udphdr _udph, *uh;
3428
3429                 if (ntohs(ih->frag_off) & IP_OFFSET)
3430                         break;
3431
3432                 offset += ihlen;
3433                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3434                 if (uh == NULL)
3435                         break;
3436
3437                 ad->u.net.sport = uh->source;
3438                 ad->u.net.dport = uh->dest;
3439                 break;
3440         }
3441
3442         case IPPROTO_DCCP: {
3443                 struct dccp_hdr _dccph, *dh;
3444
3445                 if (ntohs(ih->frag_off) & IP_OFFSET)
3446                         break;
3447
3448                 offset += ihlen;
3449                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3450                 if (dh == NULL)
3451                         break;
3452
3453                 ad->u.net.sport = dh->dccph_sport;
3454                 ad->u.net.dport = dh->dccph_dport;
3455                 break;
3456         }
3457
3458         default:
3459                 break;
3460         }
3461 out:
3462         return ret;
3463 }
3464
3465 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3466
3467 /* Returns error only if unable to parse addresses */
3468 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3469                         struct avc_audit_data *ad, u8 *proto)
3470 {
3471         u8 nexthdr;
3472         int ret = -EINVAL, offset;
3473         struct ipv6hdr _ipv6h, *ip6;
3474
3475         offset = skb_network_offset(skb);
3476         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3477         if (ip6 == NULL)
3478                 goto out;
3479
3480         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3481         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3482         ret = 0;
3483
3484         nexthdr = ip6->nexthdr;
3485         offset += sizeof(_ipv6h);
3486         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3487         if (offset < 0)
3488                 goto out;
3489
3490         if (proto)
3491                 *proto = nexthdr;
3492
3493         switch (nexthdr) {
3494         case IPPROTO_TCP: {
3495                 struct tcphdr _tcph, *th;
3496
3497                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3498                 if (th == NULL)
3499                         break;
3500
3501                 ad->u.net.sport = th->source;
3502                 ad->u.net.dport = th->dest;
3503                 break;
3504         }
3505
3506         case IPPROTO_UDP: {
3507                 struct udphdr _udph, *uh;
3508
3509                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3510                 if (uh == NULL)
3511                         break;
3512
3513                 ad->u.net.sport = uh->source;
3514                 ad->u.net.dport = uh->dest;
3515                 break;
3516         }
3517
3518         case IPPROTO_DCCP: {
3519                 struct dccp_hdr _dccph, *dh;
3520
3521                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3522                 if (dh == NULL)
3523                         break;
3524
3525                 ad->u.net.sport = dh->dccph_sport;
3526                 ad->u.net.dport = dh->dccph_dport;
3527                 break;
3528         }
3529
3530         /* includes fragments */
3531         default:
3532                 break;
3533         }
3534 out:
3535         return ret;
3536 }
3537
3538 #endif /* IPV6 */
3539
3540 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3541                              char **addrp, int src, u8 *proto)
3542 {
3543         int ret = 0;
3544
3545         switch (ad->u.net.family) {
3546         case PF_INET:
3547                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3548                 if (ret || !addrp)
3549                         break;
3550                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3551                                         &ad->u.net.v4info.daddr);
3552                 break;
3553
3554 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3555         case PF_INET6:
3556                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3557                 if (ret || !addrp)
3558                         break;
3559                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3560                                         &ad->u.net.v6info.daddr);
3561                 break;
3562 #endif  /* IPV6 */
3563         default:
3564                 break;
3565         }
3566
3567         if (unlikely(ret))
3568                 printk(KERN_WARNING
3569                        "SELinux: failure in selinux_parse_skb(),"
3570                        " unable to parse packet\n");
3571
3572         return ret;
3573 }
3574
3575 /**
3576  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3577  * @skb: the packet
3578  * @family: protocol family
3579  * @sid: the packet's peer label SID
3580  *
3581  * Description:
3582  * Check the various different forms of network peer labeling and determine
3583  * the peer label/SID for the packet; most of the magic actually occurs in
3584  * the security server function security_net_peersid_cmp().  The function
3585  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3586  * or -EACCES if @sid is invalid due to inconsistencies with the different
3587  * peer labels.
3588  *
3589  */
3590 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3591 {
3592         int err;
3593         u32 xfrm_sid;
3594         u32 nlbl_sid;
3595         u32 nlbl_type;
3596
3597         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3598         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3599
3600         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3601         if (unlikely(err)) {
3602                 printk(KERN_WARNING
3603                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3604                        " unable to determine packet's peer label\n");
3605                 return -EACCES;
3606         }
3607
3608         return 0;
3609 }
3610
3611 /* socket security operations */
3612 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3613                            u32 perms)
3614 {
3615         struct inode_security_struct *isec;
3616         struct task_security_struct *tsec;
3617         struct avc_audit_data ad;
3618         int err = 0;
3619
3620         tsec = task->security;
3621         isec = SOCK_INODE(sock)->i_security;
3622
3623         if (isec->sid == SECINITSID_KERNEL)
3624                 goto out;
3625
3626         AVC_AUDIT_DATA_INIT(&ad, NET);
3627         ad.u.net.sk = sock->sk;
3628         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3629
3630 out:
3631         return err;
3632 }
3633
3634 static int selinux_socket_create(int family, int type,
3635                                  int protocol, int kern)
3636 {
3637         int err = 0;
3638         struct task_security_struct *tsec;
3639         u32 newsid;
3640
3641         if (kern)
3642                 goto out;
3643
3644         tsec = current->security;
3645         newsid = tsec->sockcreate_sid ? : tsec->sid;
3646         err = avc_has_perm(tsec->sid, newsid,
3647                            socket_type_to_security_class(family, type,
3648                            protocol), SOCKET__CREATE, NULL);
3649
3650 out:
3651         return err;
3652 }
3653
3654 static int selinux_socket_post_create(struct socket *sock, int family,
3655                                       int type, int protocol, int kern)
3656 {
3657         int err = 0;
3658         struct inode_security_struct *isec;
3659         struct task_security_struct *tsec;
3660         struct sk_security_struct *sksec;
3661         u32 newsid;
3662
3663         isec = SOCK_INODE(sock)->i_security;
3664
3665         tsec = current->security;
3666         newsid = tsec->sockcreate_sid ? : tsec->sid;
3667         isec->sclass = socket_type_to_security_class(family, type, protocol);
3668         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3669         isec->initialized = 1;
3670
3671         if (sock->sk) {
3672                 sksec = sock->sk->sk_security;
3673                 sksec->sid = isec->sid;
3674                 sksec->sclass = isec->sclass;
3675                 err = selinux_netlbl_socket_post_create(sock);
3676         }
3677
3678         return err;
3679 }
3680
3681 /* Range of port numbers used to automatically bind.
3682    Need to determine whether we should perform a name_bind
3683    permission check between the socket and the port number. */
3684
3685 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3686 {
3687         u16 family;
3688         int err;
3689
3690         err = socket_has_perm(current, sock, SOCKET__BIND);
3691         if (err)
3692                 goto out;
3693
3694         /*
3695          * If PF_INET or PF_INET6, check name_bind permission for the port.
3696          * Multiple address binding for SCTP is not supported yet: we just
3697          * check the first address now.
3698          */
3699         family = sock->sk->sk_family;
3700         if (family == PF_INET || family == PF_INET6) {
3701                 char *addrp;
3702                 struct inode_security_struct *isec;
3703                 struct task_security_struct *tsec;
3704                 struct avc_audit_data ad;
3705                 struct sockaddr_in *addr4 = NULL;
3706                 struct sockaddr_in6 *addr6 = NULL;
3707                 unsigned short snum;
3708                 struct sock *sk = sock->sk;
3709                 u32 sid, node_perm;
3710
3711                 tsec = current->security;
3712                 isec = SOCK_INODE(sock)->i_security;
3713
3714                 if (family == PF_INET) {
3715                         addr4 = (struct sockaddr_in *)address;
3716                         snum = ntohs(addr4->sin_port);
3717                         addrp = (char *)&addr4->sin_addr.s_addr;
3718                 } else {
3719                         addr6 = (struct sockaddr_in6 *)address;
3720                         snum = ntohs(addr6->sin6_port);
3721                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3722                 }
3723
3724                 if (snum) {
3725                         int low, high;
3726
3727                         inet_get_local_port_range(&low, &high);
3728
3729                         if (snum < max(PROT_SOCK, low) || snum > high) {
3730                                 err = sel_netport_sid(sk->sk_protocol,
3731                                                       snum, &sid);
3732                                 if (err)
3733                                         goto out;
3734                                 AVC_AUDIT_DATA_INIT(&ad, NET);
3735                                 ad.u.net.sport = htons(snum);
3736                                 ad.u.net.family = family;
3737                                 err = avc_has_perm(isec->sid, sid,
3738                                                    isec->sclass,
3739                                                    SOCKET__NAME_BIND, &ad);
3740                                 if (err)
3741                                         goto out;
3742                         }
3743                 }
3744
3745                 switch (isec->sclass) {
3746                 case SECCLASS_TCP_SOCKET:
3747                         node_perm = TCP_SOCKET__NODE_BIND;
3748                         break;
3749
3750                 case SECCLASS_UDP_SOCKET:
3751                         node_perm = UDP_SOCKET__NODE_BIND;
3752                         break;
3753
3754                 case SECCLASS_DCCP_SOCKET:
3755                         node_perm = DCCP_SOCKET__NODE_BIND;
3756                         break;
3757
3758                 default:
3759                         node_perm = RAWIP_SOCKET__NODE_BIND;
3760                         break;
3761                 }
3762
3763                 err = sel_netnode_sid(addrp, family, &sid);
3764                 if (err)
3765                         goto out;
3766
3767                 AVC_AUDIT_DATA_INIT(&ad, NET);
3768                 ad.u.net.sport = htons(snum);
3769                 ad.u.net.family = family;
3770
3771                 if (family == PF_INET)
3772                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3773                 else
3774                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3775
3776                 err = avc_has_perm(isec->sid, sid,
3777                                    isec->sclass, node_perm, &ad);
3778                 if (err)
3779                         goto out;
3780         }
3781 out:
3782         return err;
3783 }
3784
3785 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3786 {
3787         struct inode_security_struct *isec;
3788         int err;
3789
3790         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3791         if (err)
3792                 return err;
3793
3794         /*
3795          * If a TCP or DCCP socket, check name_connect permission for the port.
3796          */
3797         isec = SOCK_INODE(sock)->i_security;
3798         if (isec->sclass == SECCLASS_TCP_SOCKET ||
3799             isec->sclass == SECCLASS_DCCP_SOCKET) {
3800                 struct sock *sk = sock->sk;
3801                 struct avc_audit_data ad;
3802                 struct sockaddr_in *addr4 = NULL;
3803                 struct sockaddr_in6 *addr6 = NULL;
3804                 unsigned short snum;
3805                 u32 sid, perm;
3806
3807                 if (sk->sk_family == PF_INET) {
3808                         addr4 = (struct sockaddr_in *)address;
3809                         if (addrlen < sizeof(struct sockaddr_in))
3810                                 return -EINVAL;
3811                         snum = ntohs(addr4->sin_port);
3812                 } else {
3813                         addr6 = (struct sockaddr_in6 *)address;
3814                         if (addrlen < SIN6_LEN_RFC2133)
3815                                 return -EINVAL;
3816                         snum = ntohs(addr6->sin6_port);
3817                 }
3818
3819                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3820                 if (err)
3821                         goto out;
3822
3823                 perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
3824                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3825
3826                 AVC_AUDIT_DATA_INIT(&ad, NET);
3827                 ad.u.net.dport = htons(snum);
3828                 ad.u.net.family = sk->sk_family;
3829                 err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
3830                 if (err)
3831                         goto out;
3832         }
3833
3834 out:
3835         return err;
3836 }
3837
3838 static int selinux_socket_listen(struct socket *sock, int backlog)
3839 {
3840         return socket_has_perm(current, sock, SOCKET__LISTEN);
3841 }
3842
3843 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3844 {
3845         int err;
3846         struct inode_security_struct *isec;
3847         struct inode_security_struct *newisec;
3848
3849         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3850         if (err)
3851                 return err;
3852
3853         newisec = SOCK_INODE(newsock)->i_security;
3854
3855         isec = SOCK_INODE(sock)->i_security;
3856         newisec->sclass = isec->sclass;
3857         newisec->sid = isec->sid;
3858         newisec->initialized = 1;
3859
3860         return 0;
3861 }
3862
3863 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3864                                   int size)
3865 {
3866         int rc;
3867
3868         rc = socket_has_perm(current, sock, SOCKET__WRITE);
3869         if (rc)
3870                 return rc;
3871
3872         return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
3873 }
3874
3875 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3876                                   int size, int flags)
3877 {
3878         return socket_has_perm(current, sock, SOCKET__READ);
3879 }
3880
3881 static int selinux_socket_getsockname(struct socket *sock)
3882 {
3883         return socket_has_perm(current, sock, SOCKET__GETATTR);
3884 }
3885
3886 static int selinux_socket_getpeername(struct socket *sock)
3887 {
3888         return socket_has_perm(current, sock, SOCKET__GETATTR);
3889 }
3890
3891 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3892 {
3893         int err;
3894
3895         err = socket_has_perm(current, sock, SOCKET__SETOPT);
3896         if (err)
3897                 return err;
3898
3899         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3900 }
3901
3902 static int selinux_socket_getsockopt(struct socket *sock, int level,
3903                                      int optname)
3904 {
3905         return socket_has_perm(current, sock, SOCKET__GETOPT);
3906 }
3907
3908 static int selinux_socket_shutdown(struct socket *sock, int how)
3909 {
3910         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3911 }
3912
3913 static int selinux_socket_unix_stream_connect(struct socket *sock,
3914                                               struct socket *other,
3915                                               struct sock *newsk)
3916 {
3917         struct sk_security_struct *ssec;
3918         struct inode_security_struct *isec;
3919         struct inode_security_struct *other_isec;
3920         struct avc_audit_data ad;
3921         int err;
3922
3923         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3924         if (err)
3925                 return err;
3926
3927         isec = SOCK_INODE(sock)->i_security;
3928         other_isec = SOCK_INODE(other)->i_security;
3929
3930         AVC_AUDIT_DATA_INIT(&ad, NET);
3931         ad.u.net.sk = other->sk;
3932
3933         err = avc_has_perm(isec->sid, other_isec->sid,
3934                            isec->sclass,
3935                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3936         if (err)
3937                 return err;
3938
3939         /* connecting socket */
3940         ssec = sock->sk->sk_security;
3941         ssec->peer_sid = other_isec->sid;
3942
3943         /* server child socket */
3944         ssec = newsk->sk_security;
3945         ssec->peer_sid = isec->sid;
3946         err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);
3947
3948         return err;
3949 }
3950
3951 static int selinux_socket_unix_may_send(struct socket *sock,
3952                                         struct socket *other)
3953 {
3954         struct inode_security_struct *isec;
3955         struct inode_security_struct *other_isec;
3956         struct avc_audit_data ad;
3957         int err;
3958
3959         isec = SOCK_INODE(sock)->i_security;
3960         other_isec = SOCK_INODE(other)->i_security;
3961
3962         AVC_AUDIT_DATA_INIT(&ad, NET);
3963         ad.u.net.sk = other->sk;
3964
3965         err = avc_has_perm(isec->sid, other_isec->sid,
3966                            isec->sclass, SOCKET__SENDTO, &ad);
3967         if (err)
3968                 return err;
3969
3970         return 0;
3971 }
3972
3973 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
3974                                     u32 peer_sid,
3975                                     struct avc_audit_data *ad)
3976 {
3977         int err;
3978         u32 if_sid;
3979         u32 node_sid;
3980
3981         err = sel_netif_sid(ifindex, &if_sid);
3982         if (err)
3983                 return err;
3984         err = avc_has_perm(peer_sid, if_sid,
3985                            SECCLASS_NETIF, NETIF__INGRESS, ad);
3986         if (err)
3987                 return err;
3988
3989         err = sel_netnode_sid(addrp, family, &node_sid);
3990         if (err)
3991                 return err;
3992         return avc_has_perm(peer_sid, node_sid,
3993                             SECCLASS_NODE, NODE__RECVFROM, ad);
3994 }
3995
3996 static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
3997                                                 struct sk_buff *skb,
3998                                                 struct avc_audit_data *ad,
3999                                                 u16 family,
4000                                                 char *addrp)
4001 {
4002         int err;
4003         struct sk_security_struct *sksec = sk->sk_security;
4004         u16 sk_class;
4005         u32 netif_perm, node_perm, recv_perm;
4006         u32 port_sid, node_sid, if_sid, sk_sid;
4007
4008         sk_sid = sksec->sid;
4009         sk_class = sksec->sclass;
4010
4011         switch (sk_class) {
4012         case SECCLASS_UDP_SOCKET:
4013                 netif_perm = NETIF__UDP_RECV;
4014                 node_perm = NODE__UDP_RECV;
4015                 recv_perm = UDP_SOCKET__RECV_MSG;
4016                 break;
4017         case SECCLASS_TCP_SOCKET:
4018                 netif_perm = NETIF__TCP_RECV;
4019                 node_perm = NODE__TCP_RECV;
4020                 recv_perm = TCP_SOCKET__RECV_MSG;
4021                 break;
4022         case SECCLASS_DCCP_SOCKET:
4023                 netif_perm = NETIF__DCCP_RECV;
4024                 node_perm = NODE__DCCP_RECV;
4025                 recv_perm = DCCP_SOCKET__RECV_MSG;
4026                 break;
4027         default:
4028                 netif_perm = NETIF__RAWIP_RECV;
4029                 node_perm = NODE__RAWIP_RECV;
4030                 recv_perm = 0;
4031                 break;
4032         }
4033
4034         err = sel_netif_sid(skb->iif, &if_sid);
4035         if (err)
4036                 return err;
4037         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4038         if (err)
4039                 return err;
4040
4041         err = sel_netnode_sid(addrp, family, &node_sid);
4042         if (err)
4043                 return err;
4044         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4045         if (err)
4046                 return err;
4047
4048         if (!recv_perm)
4049                 return 0;
4050         err = sel_netport_sid(sk->sk_protocol,
4051                               ntohs(ad->u.net.sport), &port_sid);
4052         if (unlikely(err)) {
4053                 printk(KERN_WARNING
4054                        "SELinux: failure in"
4055                        " selinux_sock_rcv_skb_iptables_compat(),"
4056                        " network port label not found\n");
4057                 return err;
4058         }
4059         return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
4060 }
4061
4062 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4063                                        struct avc_audit_data *ad,
4064                                        u16 family, char *addrp)
4065 {
4066         int err;
4067         struct sk_security_struct *sksec = sk->sk_security;
4068         u32 peer_sid;
4069         u32 sk_sid = sksec->sid;
4070
4071         if (selinux_compat_net)
4072                 err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
4073                                                            family, addrp);
4074         else
4075                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4076                                    PACKET__RECV, ad);
4077         if (err)
4078                 return err;
4079
4080         if (selinux_policycap_netpeer) {
4081                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4082                 if (err)
4083                         return err;
4084                 err = avc_has_perm(sk_sid, peer_sid,
4085                                    SECCLASS_PEER, PEER__RECV, ad);
4086         } else {
4087                 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
4088                 if (err)
4089                         return err;
4090                 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
4091         }
4092
4093         return err;
4094 }
4095
4096 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4097 {
4098         int err;
4099         struct sk_security_struct *sksec = sk->sk_security;
4100         u16 family = sk->sk_family;
4101         u32 sk_sid = sksec->sid;
4102         struct avc_audit_data ad;
4103         char *addrp;
4104
4105         if (family != PF_INET && family != PF_INET6)
4106                 return 0;
4107
4108         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4109         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4110                 family = PF_INET;
4111
4112         AVC_AUDIT_DATA_INIT(&ad, NET);
4113         ad.u.net.netif = skb->iif;
4114         ad.u.net.family = family;
4115         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4116         if (err)
4117                 return err;
4118
4119         /* If any sort of compatibility mode is enabled then handoff processing
4120          * to the selinux_sock_rcv_skb_compat() function to deal with the
4121          * special handling.  We do this in an attempt to keep this function
4122          * as fast and as clean as possible. */
4123         if (selinux_compat_net || !selinux_policycap_netpeer)
4124                 return selinux_sock_rcv_skb_compat(sk, skb, &ad,
4125                                                    family, addrp);
4126
4127         if (netlbl_enabled() || selinux_xfrm_enabled()) {
4128                 u32 peer_sid;
4129
4130                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4131                 if (err)
4132                         return err;
4133                 err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
4134                                                peer_sid, &ad);
4135                 if (err)
4136                         return err;
4137                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4138                                    PEER__RECV, &ad);
4139         }
4140
4141         if (selinux_secmark_enabled()) {
4142                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4143                                    PACKET__RECV, &ad);
4144                 if (err)
4145                         return err;
4146         }
4147
4148         return err;
4149 }
4150
4151 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4152                                             int __user *optlen, unsigned len)
4153 {
4154         int err = 0;
4155         char *scontext;
4156         u32 scontext_len;
4157         struct sk_security_struct *ssec;
4158         struct inode_security_struct *isec;
4159         u32 peer_sid = SECSID_NULL;
4160
4161         isec = SOCK_INODE(sock)->i_security;
4162
4163         if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4164             isec->sclass == SECCLASS_TCP_SOCKET) {
4165                 ssec = sock->sk->sk_security;
4166                 peer_sid = ssec->peer_sid;
4167         }
4168         if (peer_sid == SECSID_NULL) {
4169                 err = -ENOPROTOOPT;
4170                 goto out;
4171         }
4172
4173         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4174
4175         if (err)
4176                 goto out;
4177
4178         if (scontext_len > len) {
4179                 err = -ERANGE;
4180                 goto out_len;
4181         }
4182
4183         if (copy_to_user(optval, scontext, scontext_len))
4184                 err = -EFAULT;
4185
4186 out_len:
4187         if (put_user(scontext_len, optlen))
4188                 err = -EFAULT;
4189
4190         kfree(scontext);
4191 out:
4192         return err;
4193 }
4194
4195 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4196 {
4197         u32 peer_secid = SECSID_NULL;
4198         u16 family;
4199
4200         if (sock)
4201                 family = sock->sk->sk_family;
4202         else if (skb && skb->sk)
4203                 family = skb->sk->sk_family;
4204         else
4205                 goto out;
4206
4207         if (sock && family == PF_UNIX)
4208                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4209         else if (skb)
4210                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4211
4212 out:
4213         *secid = peer_secid;
4214         if (peer_secid == SECSID_NULL)
4215                 return -EINVAL;
4216         return 0;
4217 }
4218
4219 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4220 {
4221         return sk_alloc_security(sk, family, priority);
4222 }
4223
4224 static void selinux_sk_free_security(struct sock *sk)
4225 {
4226         sk_free_security(sk);
4227 }
4228
4229 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4230 {
4231         struct sk_security_struct *ssec = sk->sk_security;
4232         struct sk_security_struct *newssec = newsk->sk_security;
4233
4234         newssec->sid = ssec->sid;
4235         newssec->peer_sid = ssec->peer_sid;
4236         newssec->sclass = ssec->sclass;
4237
4238         selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4239 }
4240
4241 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4242 {
4243         if (!sk)
4244                 *secid = SECINITSID_ANY_SOCKET;
4245         else {
4246                 struct sk_security_struct *sksec = sk->sk_security;
4247
4248                 *secid = sksec->sid;
4249         }
4250 }
4251
4252 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4253 {
4254         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4255         struct sk_security_struct *sksec = sk->sk_security;
4256
4257         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4258             sk->sk_family == PF_UNIX)
4259                 isec->sid = sksec->sid;
4260         sksec->sclass = isec->sclass;
4261
4262         selinux_netlbl_sock_graft(sk, parent);
4263 }
4264
4265 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4266                                      struct request_sock *req)
4267 {
4268         struct sk_security_struct *sksec = sk->sk_security;
4269         int err;
4270         u32 newsid;
4271         u32 peersid;
4272
4273         err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
4274         if (err)
4275                 return err;
4276         if (peersid == SECSID_NULL) {
4277                 req->secid = sksec->sid;
4278                 req->peer_secid = SECSID_NULL;
4279                 return 0;
4280         }
4281
4282         err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4283         if (err)
4284                 return err;
4285
4286         req->secid = newsid;
4287         req->peer_secid = peersid;
4288         return 0;
4289 }
4290
4291 static void selinux_inet_csk_clone(struct sock *newsk,
4292                                    const struct request_sock *req)
4293 {
4294         struct sk_security_struct *newsksec = newsk->sk_security;
4295
4296         newsksec->sid = req->secid;
4297         newsksec->peer_sid = req->peer_secid;
4298         /* NOTE: Ideally, we should also get the isec->sid for the
4299            new socket in sync, but we don't have the isec available yet.
4300            So we will wait until sock_graft to do it, by which
4301            time it will have been created and available. */
4302
4303         /* We don't need to take any sort of lock here as we are the only
4304          * thread with access to newsksec */
4305         selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4306 }
4307
4308 static void selinux_inet_conn_established(struct sock *sk,
4309                                 struct sk_buff *skb)
4310 {
4311         struct sk_security_struct *sksec = sk->sk_security;
4312
4313         selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
4314 }
4315
4316 static void selinux_req_classify_flow(const struct request_sock *req,
4317                                       struct flowi *fl)
4318 {
4319         fl->secid = req->secid;
4320 }
4321
4322 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4323 {
4324         int err = 0;
4325         u32 perm;
4326         struct nlmsghdr *nlh;
4327         struct socket *sock = sk->sk_socket;
4328         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4329
4330         if (skb->len < NLMSG_SPACE(0)) {
4331                 err = -EINVAL;
4332                 goto out;
4333         }
4334         nlh = nlmsg_hdr(skb);
4335
4336         err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
4337         if (err) {
4338                 if (err == -EINVAL) {
4339                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4340                                   "SELinux:  unrecognized netlink message"
4341                                   " type=%hu for sclass=%hu\n",
4342                                   nlh->nlmsg_type, isec->sclass);
4343                         if (!selinux_enforcing)
4344                                 err = 0;
4345                 }
4346
4347                 /* Ignore */
4348                 if (err == -ENOENT)
4349                         err = 0;
4350                 goto out;
4351         }
4352
4353         err = socket_has_perm(current, sock, perm);
4354 out:
4355         return err;
4356 }
4357
4358 #ifdef CONFIG_NETFILTER
4359
4360 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4361                                        u16 family)
4362 {
4363         char *addrp;
4364         u32 peer_sid;
4365         struct avc_audit_data ad;
4366         u8 secmark_active;
4367         u8 peerlbl_active;
4368
4369         if (!selinux_policycap_netpeer)
4370                 return NF_ACCEPT;
4371
4372         secmark_active = selinux_secmark_enabled();
4373         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4374         if (!secmark_active && !peerlbl_active)
4375                 return NF_ACCEPT;
4376
4377         AVC_AUDIT_DATA_INIT(&ad, NET);
4378         ad.u.net.netif = ifindex;
4379         ad.u.net.family = family;
4380         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4381                 return NF_DROP;
4382
4383         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4384                 return NF_DROP;
4385
4386         if (peerlbl_active)
4387                 if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4388                                              peer_sid, &ad) != 0)
4389                         return NF_DROP;
4390
4391         if (secmark_active)
4392                 if (avc_has_perm(peer_sid, skb->secmark,
4393                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4394                         return NF_DROP;
4395
4396         return NF_ACCEPT;
4397 }
4398
4399 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4400                                          struct sk_buff *skb,
4401                                          const struct net_device *in,
4402                                          const struct net_device *out,
4403                                          int (*okfn)(struct sk_buff *))
4404 {
4405         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4406 }
4407
4408 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4409 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4410                                          struct sk_buff *skb,
4411                                          const struct net_device *in,
4412                                          const struct net_device *out,
4413                                          int (*okfn)(struct sk_buff *))
4414 {
4415         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4416 }
4417 #endif  /* IPV6 */
4418
4419 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
4420                                                 int ifindex,
4421                                                 struct avc_audit_data *ad,
4422                                                 u16 family, char *addrp)
4423 {
4424         int err;
4425         struct sk_security_struct *sksec = sk->sk_security;
4426         u16 sk_class;
4427         u32 netif_perm, node_perm, send_perm;
4428         u32 port_sid, node_sid, if_sid, sk_sid;
4429
4430         sk_sid = sksec->sid;
4431         sk_class = sksec->sclass;
4432
4433         switch (sk_class) {
4434         case SECCLASS_UDP_SOCKET:
4435                 netif_perm = NETIF__UDP_SEND;
4436                 node_perm = NODE__UDP_SEND;
4437                 send_perm = UDP_SOCKET__SEND_MSG;
4438                 break;
4439         case SECCLASS_TCP_SOCKET:
4440                 netif_perm = NETIF__TCP_SEND;
4441                 node_perm = NODE__TCP_SEND;
4442                 send_perm = TCP_SOCKET__SEND_MSG;
4443                 break;
4444         case SECCLASS_DCCP_SOCKET:
4445                 netif_perm = NETIF__DCCP_SEND;
4446                 node_perm = NODE__DCCP_SEND;
4447                 send_perm = DCCP_SOCKET__SEND_MSG;
4448                 break;
4449         default:
4450                 netif_perm = NETIF__RAWIP_SEND;
4451                 node_perm = NODE__RAWIP_SEND;
4452                 send_perm = 0;
4453                 break;
4454         }
4455
4456         err = sel_netif_sid(ifindex, &if_sid);
4457         if (err)
4458                 return err;
4459         err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
4460                 return err;
4461
4462         err = sel_netnode_sid(addrp, family, &node_sid);
4463         if (err)
4464                 return err;
4465         err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4466         if (err)
4467                 return err;
4468
4469         if (send_perm != 0)
4470                 return 0;
4471
4472         err = sel_netport_sid(sk->sk_protocol,
4473                               ntohs(ad->u.net.dport), &port_sid);
4474         if (unlikely(err)) {
4475                 printk(KERN_WARNING
4476                        "SELinux: failure in"
4477                        " selinux_ip_postroute_iptables_compat(),"
4478                        " network port label not found\n");
4479                 return err;
4480         }
4481         return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
4482 }
4483
4484 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4485                                                 int ifindex,
4486                                                 struct avc_audit_data *ad,
4487                                                 u16 family,
4488                                                 char *addrp,
4489                                                 u8 proto)
4490 {
4491         struct sock *sk = skb->sk;
4492         struct sk_security_struct *sksec;
4493
4494         if (sk == NULL)
4495                 return NF_ACCEPT;
4496         sksec = sk->sk_security;
4497
4498         if (selinux_compat_net) {
4499                 if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4500                                                          ad, family, addrp))
4501                         return NF_DROP;
4502         } else {
4503                 if (avc_has_perm(sksec->sid, skb->secmark,
4504                                  SECCLASS_PACKET, PACKET__SEND, ad))
4505                         return NF_DROP;
4506         }
4507
4508         if (selinux_policycap_netpeer)
4509                 if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
4510                         return NF_DROP;
4511
4512         return NF_ACCEPT;
4513 }
4514
4515 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4516                                          u16 family)
4517 {
4518         u32 secmark_perm;
4519         u32 peer_sid;
4520         struct sock *sk;
4521         struct avc_audit_data ad;
4522         char *addrp;
4523         u8 proto;
4524         u8 secmark_active;
4525         u8 peerlbl_active;
4526
4527         AVC_AUDIT_DATA_INIT(&ad, NET);
4528         ad.u.net.netif = ifindex;
4529         ad.u.net.family = family;
4530         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4531                 return NF_DROP;
4532
4533         /* If any sort of compatibility mode is enabled then handoff processing
4534          * to the selinux_ip_postroute_compat() function to deal with the
4535          * special handling.  We do this in an attempt to keep this function
4536          * as fast and as clean as possible. */
4537         if (selinux_compat_net || !selinux_policycap_netpeer)
4538                 return selinux_ip_postroute_compat(skb, ifindex, &ad,
4539                                                    family, addrp, proto);
4540
4541         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4542          * packet transformation so allow the packet to pass without any checks
4543          * since we'll have another chance to perform access control checks
4544          * when the packet is on it's final way out.
4545          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4546          *       is NULL, in this case go ahead and apply access control. */
4547         if (skb->dst != NULL && skb->dst->xfrm != NULL)
4548                 return NF_ACCEPT;
4549
4550         secmark_active = selinux_secmark_enabled();
4551         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4552         if (!secmark_active && !peerlbl_active)
4553                 return NF_ACCEPT;
4554
4555         /* if the packet is locally generated (skb->sk != NULL) then use the
4556          * socket's label as the peer label, otherwise the packet is being
4557          * forwarded through this system and we need to fetch the peer label
4558          * directly from the packet */
4559         sk = skb->sk;
4560         if (sk) {
4561                 struct sk_security_struct *sksec = sk->sk_security;
4562                 peer_sid = sksec->sid;
4563                 secmark_perm = PACKET__SEND;
4564         } else {
4565                 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4566                                 return NF_DROP;
4567                 secmark_perm = PACKET__FORWARD_OUT;
4568         }
4569
4570         if (secmark_active)
4571                 if (avc_has_perm(peer_sid, skb->secmark,
4572                                  SECCLASS_PACKET, secmark_perm, &ad))
4573                         return NF_DROP;
4574
4575         if (peerlbl_active) {
4576                 u32 if_sid;
4577                 u32 node_sid;
4578
4579                 if (sel_netif_sid(ifindex, &if_sid))
4580                         return NF_DROP;
4581                 if (avc_has_perm(peer_sid, if_sid,
4582                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4583                         return NF_DROP;
4584
4585                 if (sel_netnode_sid(addrp, family, &node_sid))
4586                         return NF_DROP;
4587                 if (avc_has_perm(peer_sid, node_sid,
4588                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4589                         return NF_DROP;
4590         }
4591
4592         return NF_ACCEPT;
4593 }
4594
4595 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4596                                            struct sk_buff *skb,
4597                                            const struct net_device *in,
4598                                            const struct net_device *out,
4599                                            int (*okfn)(struct sk_buff *))
4600 {
4601         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4602 }
4603
4604 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4605 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4606                                            struct sk_buff *skb,
4607                                            const struct net_device *in,
4608                                            const struct net_device *out,
4609                                            int (*okfn)(struct sk_buff *))
4610 {
4611         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4612 }
4613 #endif  /* IPV6 */
4614
4615 #endif  /* CONFIG_NETFILTER */
4616
4617 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4618 {
4619         int err;
4620
4621         err = secondary_ops->netlink_send(sk, skb);
4622         if (err)
4623                 return err;
4624
4625         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
4626                 err = selinux_nlmsg_perm(sk, skb);
4627
4628         return err;
4629 }
4630
4631 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4632 {
4633         int err;
4634         struct avc_audit_data ad;
4635
4636         err = secondary_ops->netlink_recv(skb, capability);
4637         if (err)
4638                 return err;
4639
4640         AVC_AUDIT_DATA_INIT(&ad, CAP);
4641         ad.u.cap = capability;
4642
4643         return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4644                             SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
4645 }
4646
4647 static int ipc_alloc_security(struct task_struct *task,
4648                               struct kern_ipc_perm *perm,
4649                               u16 sclass)
4650 {
4651         struct task_security_struct *tsec = task->security;
4652         struct ipc_security_struct *isec;
4653
4654         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4655         if (!isec)
4656                 return -ENOMEM;
4657
4658         isec->sclass = sclass;
4659         isec->sid = tsec->sid;
4660         perm->security = isec;
4661
4662         return 0;
4663 }
4664
4665 static void ipc_free_security(struct kern_ipc_perm *perm)
4666 {
4667         struct ipc_security_struct *isec = perm->security;
4668         perm->security = NULL;
4669         kfree(isec);
4670 }
4671
4672 static int msg_msg_alloc_security(struct msg_msg *msg)
4673 {
4674         struct msg_security_struct *msec;
4675
4676         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4677         if (!msec)
4678                 return -ENOMEM;
4679
4680         msec->sid = SECINITSID_UNLABELED;
4681         msg->security = msec;
4682
4683         return 0;
4684 }
4685
4686 static void msg_msg_free_security(struct msg_msg *msg)
4687 {
4688         struct msg_security_struct *msec = msg->security;
4689
4690         msg->security = NULL;
4691         kfree(msec);
4692 }
4693
4694 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4695                         u32 perms)
4696 {
4697         struct task_security_struct *tsec;
4698         struct ipc_security_struct *isec;
4699         struct avc_audit_data ad;
4700
4701         tsec = current->security;
4702         isec = ipc_perms->security;
4703
4704         AVC_AUDIT_DATA_INIT(&ad, IPC);
4705         ad.u.ipc_id = ipc_perms->key;
4706
4707         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
4708 }
4709
4710 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4711 {
4712         return msg_msg_alloc_security(msg);
4713 }
4714
4715 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4716 {
4717         msg_msg_free_security(msg);
4718 }
4719
4720 /* message queue security operations */
4721 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4722 {
4723         struct task_security_struct *tsec;
4724         struct ipc_security_struct *isec;
4725         struct avc_audit_data ad;
4726         int rc;
4727
4728         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4729         if (rc)
4730                 return rc;
4731
4732         tsec = current->security;
4733         isec = msq->q_perm.security;
4734
4735         AVC_AUDIT_DATA_INIT(&ad, IPC);
4736         ad.u.ipc_id = msq->q_perm.key;
4737
4738         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4739                           MSGQ__CREATE, &ad);
4740         if (rc) {
4741                 ipc_free_security(&msq->q_perm);
4742                 return rc;
4743         }
4744         return 0;
4745 }
4746
4747 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4748 {
4749         ipc_free_security(&msq->q_perm);
4750 }
4751
4752 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4753 {
4754         struct task_security_struct *tsec;
4755         struct ipc_security_struct *isec;
4756         struct avc_audit_data ad;
4757
4758         tsec = current->security;
4759         isec = msq->q_perm.security;
4760
4761         AVC_AUDIT_DATA_INIT(&ad, IPC);
4762         ad.u.ipc_id = msq->q_perm.key;
4763
4764         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4765                             MSGQ__ASSOCIATE, &ad);
4766 }
4767
4768 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4769 {
4770         int err;
4771         int perms;
4772
4773         switch (cmd) {
4774         case IPC_INFO:
4775         case MSG_INFO:
4776                 /* No specific object, just general system-wide information. */
4777                 return task_has_system(current, SYSTEM__IPC_INFO);
4778         case IPC_STAT:
4779         case MSG_STAT:
4780                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4781                 break;
4782         case IPC_SET:
4783                 perms = MSGQ__SETATTR;
4784                 break;
4785         case IPC_RMID:
4786                 perms = MSGQ__DESTROY;
4787                 break;
4788         default:
4789                 return 0;
4790         }
4791
4792         err = ipc_has_perm(&msq->q_perm, perms);
4793         return err;
4794 }
4795
4796 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4797 {
4798         struct task_security_struct *tsec;
4799         struct ipc_security_struct *isec;
4800         struct msg_security_struct *msec;
4801         struct avc_audit_data ad;
4802         int rc;
4803
4804         tsec = current->security;
4805         isec = msq->q_perm.security;
4806         msec = msg->security;
4807
4808         /*
4809          * First time through, need to assign label to the message
4810          */
4811         if (msec->sid == SECINITSID_UNLABELED) {
4812                 /*
4813                  * Compute new sid based on current process and
4814                  * message queue this message will be stored in
4815                  */
4816                 rc = security_transition_sid(tsec->sid,
4817                                              isec->sid,
4818                                              SECCLASS_MSG,
4819                                              &msec->sid);
4820                 if (rc)
4821                         return rc;
4822         }
4823
4824         AVC_AUDIT_DATA_INIT(&ad, IPC);
4825         ad.u.ipc_id = msq->q_perm.key;
4826
4827         /* Can this process write to the queue? */
4828         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_MSGQ,
4829                           MSGQ__WRITE, &ad);
4830         if (!rc)
4831                 /* Can this process send the message */
4832                 rc = avc_has_perm(tsec->sid, msec->sid,
4833                                   SECCLASS_MSG, MSG__SEND, &ad);
4834         if (!rc)
4835                 /* Can the message be put in the queue? */
4836                 rc = avc_has_perm(msec->sid, isec->sid,
4837                                   SECCLASS_MSGQ, MSGQ__ENQUEUE, &ad);
4838
4839         return rc;
4840 }
4841
4842 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4843                                     struct task_struct *target,
4844                                     long type, int mode)
4845 {
4846         struct task_security_struct *tsec;
4847         struct ipc_security_struct *isec;
4848         struct msg_security_struct *msec;
4849         struct avc_audit_data ad;
4850         int rc;
4851
4852         tsec = target->security;
4853         isec = msq->q_perm.security;
4854         msec = msg->security;
4855
4856         AVC_AUDIT_DATA_INIT(&ad, IPC);
4857         ad.u.ipc_id = msq->q_perm.key;
4858
4859         rc = avc_has_perm(tsec->sid, isec->sid,
4860                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4861         if (!rc)
4862                 rc = avc_has_perm(tsec->sid, msec->sid,
4863                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4864         return rc;
4865 }
4866
4867 /* Shared Memory security operations */
4868 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4869 {
4870         struct task_security_struct *tsec;
4871         struct ipc_security_struct *isec;
4872         struct avc_audit_data ad;
4873         int rc;
4874
4875         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4876         if (rc)
4877                 return rc;
4878
4879         tsec = current->security;
4880         isec = shp->shm_perm.security;
4881
4882         AVC_AUDIT_DATA_INIT(&ad, IPC);
4883         ad.u.ipc_id = shp->shm_perm.key;
4884
4885         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4886                           SHM__CREATE, &ad);
4887         if (rc) {
4888                 ipc_free_security(&shp->shm_perm);
4889                 return rc;
4890         }
4891         return 0;
4892 }
4893
4894 static void selinux_shm_free_security(struct shmid_kernel *shp)
4895 {
4896         ipc_free_security(&shp->shm_perm);
4897 }
4898
4899 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4900 {
4901         struct task_security_struct *tsec;
4902         struct ipc_security_struct *isec;
4903         struct avc_audit_data ad;
4904
4905         tsec = current->security;
4906         isec = shp->shm_perm.security;
4907
4908         AVC_AUDIT_DATA_INIT(&ad, IPC);
4909         ad.u.ipc_id = shp->shm_perm.key;
4910
4911         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SHM,
4912                             SHM__ASSOCIATE, &ad);
4913 }
4914
4915 /* Note, at this point, shp is locked down */
4916 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4917 {
4918         int perms;
4919         int err;
4920
4921         switch (cmd) {
4922         case IPC_INFO:
4923         case SHM_INFO:
4924                 /* No specific object, just general system-wide information. */
4925                 return task_has_system(current, SYSTEM__IPC_INFO);
4926         case IPC_STAT:
4927         case SHM_STAT:
4928                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4929                 break;
4930         case IPC_SET:
4931                 perms = SHM__SETATTR;
4932                 break;
4933         case SHM_LOCK:
4934         case SHM_UNLOCK:
4935                 perms = SHM__LOCK;
4936                 break;
4937         case IPC_RMID:
4938                 perms = SHM__DESTROY;
4939                 break;
4940         default:
4941                 return 0;
4942         }
4943
4944         err = ipc_has_perm(&shp->shm_perm, perms);
4945         return err;
4946 }
4947
4948 static int selinux_shm_shmat(struct shmid_kernel *shp,
4949                              char __user *shmaddr, int shmflg)
4950 {
4951         u32 perms;
4952         int rc;
4953
4954         rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
4955         if (rc)
4956                 return rc;
4957
4958         if (shmflg & SHM_RDONLY)
4959                 perms = SHM__READ;
4960         else
4961                 perms = SHM__READ | SHM__WRITE;
4962
4963         return ipc_has_perm(&shp->shm_perm, perms);
4964 }
4965
4966 /* Semaphore security operations */
4967 static int selinux_sem_alloc_security(struct sem_array *sma)
4968 {
4969         struct task_security_struct *tsec;
4970         struct ipc_security_struct *isec;
4971         struct avc_audit_data ad;
4972         int rc;
4973
4974         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
4975         if (rc)
4976                 return rc;
4977
4978         tsec = current->security;
4979         isec = sma->sem_perm.security;
4980
4981         AVC_AUDIT_DATA_INIT(&ad, IPC);
4982         ad.u.ipc_id = sma->sem_perm.key;
4983
4984         rc = avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
4985                           SEM__CREATE, &ad);
4986         if (rc) {
4987                 ipc_free_security(&sma->sem_perm);
4988                 return rc;
4989         }
4990         return 0;
4991 }
4992
4993 static void selinux_sem_free_security(struct sem_array *sma)
4994 {
4995         ipc_free_security(&sma->sem_perm);
4996 }
4997
4998 static int selinux_sem_associate(struct sem_array *sma, int semflg)
4999 {
5000         struct task_security_struct *tsec;
5001         struct ipc_security_struct *isec;
5002         struct avc_audit_data ad;
5003
5004         tsec = current->security;
5005         isec = sma->sem_perm.security;
5006
5007         AVC_AUDIT_DATA_INIT(&ad, IPC);
5008         ad.u.ipc_id = sma->sem_perm.key;
5009
5010         return avc_has_perm(tsec->sid, isec->sid, SECCLASS_SEM,
5011                             SEM__ASSOCIATE, &ad);
5012 }
5013
5014 /* Note, at this point, sma is locked down */
5015 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5016 {
5017         int err;
5018         u32 perms;
5019
5020         switch (cmd) {
5021         case IPC_INFO:
5022         case SEM_INFO:
5023                 /* No specific object, just general system-wide information. */
5024                 return task_has_system(current, SYSTEM__IPC_INFO);
5025         case GETPID:
5026         case GETNCNT:
5027         case GETZCNT:
5028                 perms = SEM__GETATTR;
5029                 break;
5030         case GETVAL:
5031         case GETALL:
5032                 perms = SEM__READ;
5033                 break;
5034         case SETVAL:
5035         case SETALL:
5036                 perms = SEM__WRITE;
5037                 break;
5038         case IPC_RMID:
5039                 perms = SEM__DESTROY;
5040                 break;
5041         case IPC_SET:
5042                 perms = SEM__SETATTR;
5043                 break;
5044         case IPC_STAT:
5045         case SEM_STAT:
5046                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5047                 break;
5048         default:
5049                 return 0;
5050         }
5051
5052         err = ipc_has_perm(&sma->sem_perm, perms);
5053         return err;
5054 }
5055
5056 static int selinux_sem_semop(struct sem_array *sma,
5057                              struct sembuf *sops, unsigned nsops, int alter)
5058 {
5059         u32 perms;
5060
5061         if (alter)
5062                 perms = SEM__READ | SEM__WRITE;
5063         else
5064                 perms = SEM__READ;
5065
5066         return ipc_has_perm(&sma->sem_perm, perms);
5067 }
5068
5069 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5070 {
5071         u32 av = 0;
5072
5073         av = 0;
5074         if (flag & S_IRUGO)
5075                 av |= IPC__UNIX_READ;
5076         if (flag & S_IWUGO)
5077                 av |= IPC__UNIX_WRITE;
5078
5079         if (av == 0)
5080                 return 0;
5081
5082         return ipc_has_perm(ipcp, av);
5083 }
5084
5085 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5086 {
5087         struct ipc_security_struct *isec = ipcp->security;
5088         *secid = isec->sid;
5089 }
5090
5091 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5092 {
5093         if (inode)
5094                 inode_doinit_with_dentry(inode, dentry);
5095 }
5096
5097 static int selinux_getprocattr(struct task_struct *p,
5098                                char *name, char **value)
5099 {
5100         struct task_security_struct *tsec;
5101         u32 sid;
5102         int error;
5103         unsigned len;
5104
5105         if (current != p) {
5106                 error = task_has_perm(current, p, PROCESS__GETATTR);
5107                 if (error)
5108                         return error;
5109         }
5110
5111         tsec = p->security;
5112
5113         if (!strcmp(name, "current"))
5114                 sid = tsec->sid;
5115         else if (!strcmp(name, "prev"))
5116                 sid = tsec->osid;
5117         else if (!strcmp(name, "exec"))
5118                 sid = tsec->exec_sid;
5119         else if (!strcmp(name, "fscreate"))
5120                 sid = tsec->create_sid;
5121         else if (!strcmp(name, "keycreate"))
5122                 sid = tsec->keycreate_sid;
5123         else if (!strcmp(name, "sockcreate"))
5124                 sid = tsec->sockcreate_sid;
5125         else
5126                 return -EINVAL;
5127
5128         if (!sid)
5129                 return 0;
5130
5131         error = security_sid_to_context(sid, value, &len);
5132         if (error)
5133                 return error;
5134         return len;
5135 }
5136
5137 static int selinux_setprocattr(struct task_struct *p,
5138                                char *name, void *value, size_t size)
5139 {
5140         struct task_security_struct *tsec;
5141         struct task_struct *tracer;
5142         u32 sid = 0;
5143         int error;
5144         char *str = value;
5145
5146         if (current != p) {
5147                 /* SELinux only allows a process to change its own
5148                    security attributes. */
5149                 return -EACCES;
5150         }
5151
5152         /*
5153          * Basic control over ability to set these attributes at all.
5154          * current == p, but we'll pass them separately in case the
5155          * above restriction is ever removed.
5156          */
5157         if (!strcmp(name, "exec"))
5158                 error = task_has_perm(current, p, PROCESS__SETEXEC);
5159         else if (!strcmp(name, "fscreate"))
5160                 error = task_has_perm(current, p, PROCESS__SETFSCREATE);
5161         else if (!strcmp(name, "keycreate"))
5162                 error = task_has_perm(current, p, PROCESS__SETKEYCREATE);
5163         else if (!strcmp(name, "sockcreate"))
5164                 error = task_has_perm(current, p, PROCESS__SETSOCKCREATE);
5165         else if (!strcmp(name, "current"))
5166                 error = task_has_perm(current, p, PROCESS__SETCURRENT);
5167         else
5168                 error = -EINVAL;
5169         if (error)
5170                 return error;
5171
5172         /* Obtain a SID for the context, if one was specified. */
5173         if (size && str[1] && str[1] != '\n') {
5174                 if (str[size-1] == '\n') {
5175                         str[size-1] = 0;
5176                         size--;
5177                 }
5178                 error = security_context_to_sid(value, size, &sid);
5179                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5180                         if (!capable(CAP_MAC_ADMIN))
5181                                 return error;
5182                         error = security_context_to_sid_force(value, size,
5183                                                               &sid);
5184                 }
5185                 if (error)
5186                         return error;
5187         }
5188
5189         /* Permission checking based on the specified context is
5190            performed during the actual operation (execve,
5191            open/mkdir/...), when we know the full context of the
5192            operation.  See selinux_bprm_set_security for the execve
5193            checks and may_create for the file creation checks. The
5194            operation will then fail if the context is not permitted. */
5195         tsec = p->security;
5196         if (!strcmp(name, "exec"))
5197                 tsec->exec_sid = sid;
5198         else if (!strcmp(name, "fscreate"))
5199                 tsec->create_sid = sid;
5200         else if (!strcmp(name, "keycreate")) {
5201                 error = may_create_key(sid, p);
5202                 if (error)
5203                         return error;
5204                 tsec->keycreate_sid = sid;
5205         } else if (!strcmp(name, "sockcreate"))
5206                 tsec->sockcreate_sid = sid;
5207         else if (!strcmp(name, "current")) {
5208                 struct av_decision avd;
5209
5210                 if (sid == 0)
5211                         return -EINVAL;
5212
5213                 /* Only allow single threaded processes to change context */
5214                 if (atomic_read(&p->mm->mm_users) != 1) {
5215                         struct task_struct *g, *t;
5216                         struct mm_struct *mm = p->mm;
5217                         read_lock(&tasklist_lock);
5218                         do_each_thread(g, t) {
5219                                 if (t->mm == mm && t != p) {
5220                                         read_unlock(&tasklist_lock);
5221                                         return -EPERM;
5222                                 }
5223                         } while_each_thread(g, t);
5224                         read_unlock(&tasklist_lock);
5225                 }
5226
5227                 /* Check permissions for the transition. */
5228                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5229                                      PROCESS__DYNTRANSITION, NULL);
5230                 if (error)
5231                         return error;
5232
5233                 /* Check for ptracing, and update the task SID if ok.
5234                    Otherwise, leave SID unchanged and fail. */
5235                 task_lock(p);
5236                 rcu_read_lock();
5237                 tracer = tracehook_tracer_task(p);
5238                 if (tracer != NULL) {
5239                         struct task_security_struct *ptsec = tracer->security;
5240                         u32 ptsid = ptsec->sid;
5241                         rcu_read_unlock();
5242                         error = avc_has_perm_noaudit(ptsid, sid,
5243                                                      SECCLASS_PROCESS,
5244                                                      PROCESS__PTRACE, 0, &avd);
5245                         if (!error)
5246                                 tsec->sid = sid;
5247                         task_unlock(p);
5248                         avc_audit(ptsid, sid, SECCLASS_PROCESS,
5249                                   PROCESS__PTRACE, &avd, error, NULL);
5250                         if (error)
5251                                 return error;
5252                 } else {
5253                         rcu_read_unlock();
5254                         tsec->sid = sid;
5255                         task_unlock(p);
5256                 }
5257         } else
5258                 return -EINVAL;
5259
5260         return size;
5261 }
5262
5263 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5264 {
5265         return security_sid_to_context(secid, secdata, seclen);
5266 }
5267
5268 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5269 {
5270         return security_context_to_sid(secdata, seclen, secid);
5271 }
5272
5273 static void selinux_release_secctx(char *secdata, u32 seclen)
5274 {
5275         kfree(secdata);
5276 }
5277
5278 #ifdef CONFIG_KEYS
5279
5280 static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
5281                              unsigned long flags)
5282 {
5283         struct task_security_struct *tsec = tsk->security;
5284         struct key_security_struct *ksec;
5285
5286         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5287         if (!ksec)
5288                 return -ENOMEM;
5289
5290         if (tsec->keycreate_sid)
5291                 ksec->sid = tsec->keycreate_sid;
5292         else
5293                 ksec->sid = tsec->sid;
5294         k->security = ksec;
5295
5296         return 0;
5297 }
5298
5299 static void selinux_key_free(struct key *k)
5300 {
5301         struct key_security_struct *ksec = k->security;
5302
5303         k->security = NULL;
5304         kfree(ksec);
5305 }
5306
5307 static int selinux_key_permission(key_ref_t key_ref,
5308                             struct task_struct *ctx,
5309                             key_perm_t perm)
5310 {
5311         struct key *key;
5312         struct task_security_struct *tsec;
5313         struct key_security_struct *ksec;
5314
5315         key = key_ref_to_ptr(key_ref);
5316
5317         tsec = ctx->security;
5318         ksec = key->security;
5319
5320         /* if no specific permissions are requested, we skip the
5321            permission check. No serious, additional covert channels
5322            appear to be created. */
5323         if (perm == 0)
5324                 return 0;
5325
5326         return avc_has_perm(tsec->sid, ksec->sid,
5327                             SECCLASS_KEY, perm, NULL);
5328 }
5329
5330 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5331 {
5332         struct key_security_struct *ksec = key->security;
5333         char *context = NULL;
5334         unsigned len;
5335         int rc;
5336
5337         rc = security_sid_to_context(ksec->sid, &context, &len);
5338         if (!rc)
5339                 rc = len;
5340         *_buffer = context;
5341         return rc;
5342 }
5343
5344 #endif
5345
5346 static struct security_operations selinux_ops = {
5347         .name =                         "selinux",
5348
5349         .ptrace =                       selinux_ptrace,
5350         .capget =                       selinux_capget,
5351         .capset_check =                 selinux_capset_check,
5352         .capset_set =                   selinux_capset_set,
5353         .sysctl =                       selinux_sysctl,
5354         .capable =                      selinux_capable,
5355         .quotactl =                     selinux_quotactl,
5356         .quota_on =                     selinux_quota_on,
5357         .syslog =                       selinux_syslog,
5358         .vm_enough_memory =             selinux_vm_enough_memory,
5359
5360         .netlink_send =                 selinux_netlink_send,
5361         .netlink_recv =                 selinux_netlink_recv,
5362
5363         .bprm_alloc_security =          selinux_bprm_alloc_security,
5364         .bprm_free_security =           selinux_bprm_free_security,
5365         .bprm_apply_creds =             selinux_bprm_apply_creds,
5366         .bprm_post_apply_creds =        selinux_bprm_post_apply_creds,
5367         .bprm_set_security =            selinux_bprm_set_security,
5368         .bprm_check_security =          selinux_bprm_check_security,
5369         .bprm_secureexec =              selinux_bprm_secureexec,
5370
5371         .sb_alloc_security =            selinux_sb_alloc_security,
5372         .sb_free_security =             selinux_sb_free_security,
5373         .sb_copy_data =                 selinux_sb_copy_data,
5374         .sb_kern_mount =                selinux_sb_kern_mount,
5375         .sb_show_options =              selinux_sb_show_options,
5376         .sb_statfs =                    selinux_sb_statfs,
5377         .sb_mount =                     selinux_mount,
5378         .sb_umount =                    selinux_umount,
5379         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5380         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5381         .sb_parse_opts_str =            selinux_parse_opts_str,
5382
5383
5384         .inode_alloc_security =         selinux_inode_alloc_security,
5385         .inode_free_security =          selinux_inode_free_security,
5386         .inode_init_security =          selinux_inode_init_security,
5387         .inode_create =                 selinux_inode_create,
5388         .inode_link =                   selinux_inode_link,
5389         .inode_unlink =                 selinux_inode_unlink,
5390         .inode_symlink =                selinux_inode_symlink,
5391         .inode_mkdir =                  selinux_inode_mkdir,
5392         .inode_rmdir =                  selinux_inode_rmdir,
5393         .inode_mknod =                  selinux_inode_mknod,
5394         .inode_rename =                 selinux_inode_rename,
5395         .inode_readlink =               selinux_inode_readlink,
5396         .inode_follow_link =            selinux_inode_follow_link,
5397         .inode_permission =             selinux_inode_permission,
5398         .inode_setattr =                selinux_inode_setattr,
5399         .inode_getattr =                selinux_inode_getattr,
5400         .inode_setxattr =               selinux_inode_setxattr,
5401         .inode_post_setxattr =          selinux_inode_post_setxattr,
5402         .inode_getxattr =               selinux_inode_getxattr,
5403         .inode_listxattr =              selinux_inode_listxattr,
5404         .inode_removexattr =            selinux_inode_removexattr,
5405         .inode_getsecurity =            selinux_inode_getsecurity,
5406         .inode_setsecurity =            selinux_inode_setsecurity,
5407         .inode_listsecurity =           selinux_inode_listsecurity,
5408         .inode_need_killpriv =          selinux_inode_need_killpriv,
5409         .inode_killpriv =               selinux_inode_killpriv,
5410         .inode_getsecid =               selinux_inode_getsecid,
5411
5412         .file_permission =              selinux_file_permission,
5413         .file_alloc_security =          selinux_file_alloc_security,
5414         .file_free_security =           selinux_file_free_security,
5415         .file_ioctl =                   selinux_file_ioctl,
5416         .file_mmap =                    selinux_file_mmap,
5417         .file_mprotect =                selinux_file_mprotect,
5418         .file_lock =                    selinux_file_lock,
5419         .file_fcntl =                   selinux_file_fcntl,
5420         .file_set_fowner =              selinux_file_set_fowner,
5421         .file_send_sigiotask =          selinux_file_send_sigiotask,
5422         .file_receive =                 selinux_file_receive,
5423
5424         .dentry_open =                  selinux_dentry_open,
5425
5426         .task_create =                  selinux_task_create,
5427         .task_alloc_security =          selinux_task_alloc_security,
5428         .task_free_security =           selinux_task_free_security,
5429         .task_setuid =                  selinux_task_setuid,
5430         .task_post_setuid =             selinux_task_post_setuid,
5431         .task_setgid =                  selinux_task_setgid,
5432         .task_setpgid =                 selinux_task_setpgid,
5433         .task_getpgid =                 selinux_task_getpgid,
5434         .task_getsid =                  selinux_task_getsid,
5435         .task_getsecid =                selinux_task_getsecid,
5436         .task_setgroups =               selinux_task_setgroups,
5437         .task_setnice =                 selinux_task_setnice,
5438         .task_setioprio =               selinux_task_setioprio,
5439         .task_getioprio =               selinux_task_getioprio,
5440         .task_setrlimit =               selinux_task_setrlimit,
5441         .task_setscheduler =            selinux_task_setscheduler,
5442         .task_getscheduler =            selinux_task_getscheduler,
5443         .task_movememory =              selinux_task_movememory,
5444         .task_kill =                    selinux_task_kill,
5445         .task_wait =                    selinux_task_wait,
5446         .task_prctl =                   selinux_task_prctl,
5447         .task_reparent_to_init =        selinux_task_reparent_to_init,
5448         .task_to_inode =                selinux_task_to_inode,
5449
5450         .ipc_permission =               selinux_ipc_permission,
5451         .ipc_getsecid =                 selinux_ipc_getsecid,
5452
5453         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5454         .msg_msg_free_security =        selinux_msg_msg_free_security,
5455
5456         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5457         .msg_queue_free_security =      selinux_msg_queue_free_security,
5458         .msg_queue_associate =          selinux_msg_queue_associate,
5459         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5460         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5461         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5462
5463         .shm_alloc_security =           selinux_shm_alloc_security,
5464         .shm_free_security =            selinux_shm_free_security,
5465         .shm_associate =                selinux_shm_associate,
5466         .shm_shmctl =                   selinux_shm_shmctl,
5467         .shm_shmat =                    selinux_shm_shmat,
5468
5469         .sem_alloc_security =           selinux_sem_alloc_security,
5470         .sem_free_security =            selinux_sem_free_security,
5471         .sem_associate =                selinux_sem_associate,
5472         .sem_semctl =                   selinux_sem_semctl,
5473         .sem_semop =                    selinux_sem_semop,
5474
5475         .d_instantiate =                selinux_d_instantiate,
5476
5477         .getprocattr =                  selinux_getprocattr,
5478         .setprocattr =                  selinux_setprocattr,
5479
5480         .secid_to_secctx =              selinux_secid_to_secctx,
5481         .secctx_to_secid =              selinux_secctx_to_secid,
5482         .release_secctx =               selinux_release_secctx,
5483
5484         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5485         .unix_may_send =                selinux_socket_unix_may_send,
5486
5487         .socket_create =                selinux_socket_create,
5488         .socket_post_create =           selinux_socket_post_create,
5489         .socket_bind =                  selinux_socket_bind,
5490         .socket_connect =               selinux_socket_connect,
5491         .socket_listen =                selinux_socket_listen,
5492         .socket_accept =                selinux_socket_accept,
5493         .socket_sendmsg =               selinux_socket_sendmsg,
5494         .socket_recvmsg =               selinux_socket_recvmsg,
5495         .socket_getsockname =           selinux_socket_getsockname,
5496         .socket_getpeername =           selinux_socket_getpeername,
5497         .socket_getsockopt =            selinux_socket_getsockopt,
5498         .socket_setsockopt =            selinux_socket_setsockopt,
5499         .socket_shutdown =              selinux_socket_shutdown,
5500         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5501         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5502         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5503         .sk_alloc_security =            selinux_sk_alloc_security,
5504         .sk_free_security =             selinux_sk_free_security,
5505         .sk_clone_security =            selinux_sk_clone_security,
5506         .sk_getsecid =                  selinux_sk_getsecid,
5507         .sock_graft =                   selinux_sock_graft,
5508         .inet_conn_request =            selinux_inet_conn_request,
5509         .inet_csk_clone =               selinux_inet_csk_clone,
5510         .inet_conn_established =        selinux_inet_conn_established,
5511         .req_classify_flow =            selinux_req_classify_flow,
5512
5513 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5514         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5515         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5516         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5517         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5518         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5519         .xfrm_state_free_security =     selinux_xfrm_state_free,
5520         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5521         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5522         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5523         .xfrm_decode_session =          selinux_xfrm_decode_session,
5524 #endif
5525
5526 #ifdef CONFIG_KEYS
5527         .key_alloc =                    selinux_key_alloc,
5528         .key_free =                     selinux_key_free,
5529         .key_permission =               selinux_key_permission,
5530         .key_getsecurity =              selinux_key_getsecurity,
5531 #endif
5532
5533 #ifdef CONFIG_AUDIT
5534         .audit_rule_init =              selinux_audit_rule_init,
5535         .audit_rule_known =             selinux_audit_rule_known,
5536         .audit_rule_match =             selinux_audit_rule_match,
5537         .audit_rule_free =              selinux_audit_rule_free,
5538 #endif
5539 };
5540
5541 static __init int selinux_init(void)
5542 {
5543         struct task_security_struct *tsec;
5544
5545         if (!security_module_enable(&selinux_ops)) {
5546                 selinux_enabled = 0;
5547                 return 0;
5548         }
5549
5550         if (!selinux_enabled) {
5551                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5552                 return 0;
5553         }
5554
5555         printk(KERN_INFO "SELinux:  Initializing.\n");
5556
5557         /* Set the security state for the initial task. */
5558         if (task_alloc_security(current))
5559                 panic("SELinux:  Failed to initialize initial task.\n");
5560         tsec = current->security;
5561         tsec->osid = tsec->sid = SECINITSID_KERNEL;
5562
5563         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5564                                             sizeof(struct inode_security_struct),
5565                                             0, SLAB_PANIC, NULL);
5566         avc_init();
5567
5568         secondary_ops = security_ops;
5569         if (!secondary_ops)
5570                 panic("SELinux: No initial security operations\n");
5571         if (register_security(&selinux_ops))
5572                 panic("SELinux: Unable to register with kernel.\n");
5573
5574         if (selinux_enforcing)
5575                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5576         else
5577                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5578
5579         return 0;
5580 }
5581
5582 void selinux_complete_init(void)
5583 {
5584         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5585
5586         /* Set up any superblocks initialized prior to the policy load. */
5587         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5588         spin_lock(&sb_lock);
5589         spin_lock(&sb_security_lock);
5590 next_sb:
5591         if (!list_empty(&superblock_security_head)) {
5592                 struct superblock_security_struct *sbsec =
5593                                 list_entry(superblock_security_head.next,
5594                                            struct superblock_security_struct,
5595                                            list);
5596                 struct super_block *sb = sbsec->sb;
5597                 sb->s_count++;
5598                 spin_unlock(&sb_security_lock);
5599                 spin_unlock(&sb_lock);
5600                 down_read(&sb->s_umount);
5601                 if (sb->s_root)
5602                         superblock_doinit(sb, NULL);
5603                 drop_super(sb);
5604                 spin_lock(&sb_lock);
5605                 spin_lock(&sb_security_lock);
5606                 list_del_init(&sbsec->list);
5607                 goto next_sb;
5608         }
5609         spin_unlock(&sb_security_lock);
5610         spin_unlock(&sb_lock);
5611 }
5612
5613 /* SELinux requires early initialization in order to label
5614    all processes and objects when they are created. */
5615 security_initcall(selinux_init);
5616
5617 #if defined(CONFIG_NETFILTER)
5618
5619 static struct nf_hook_ops selinux_ipv4_ops[] = {
5620         {
5621                 .hook =         selinux_ipv4_postroute,
5622                 .owner =        THIS_MODULE,
5623                 .pf =           PF_INET,
5624                 .hooknum =      NF_INET_POST_ROUTING,
5625                 .priority =     NF_IP_PRI_SELINUX_LAST,
5626         },
5627         {
5628                 .hook =         selinux_ipv4_forward,
5629                 .owner =        THIS_MODULE,
5630                 .pf =           PF_INET,
5631                 .hooknum =      NF_INET_FORWARD,
5632                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5633         }
5634 };
5635
5636 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5637
5638 static struct nf_hook_ops selinux_ipv6_ops[] = {
5639         {
5640                 .hook =         selinux_ipv6_postroute,
5641                 .owner =        THIS_MODULE,
5642                 .pf =           PF_INET6,
5643                 .hooknum =      NF_INET_POST_ROUTING,
5644                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5645         },
5646         {
5647                 .hook =         selinux_ipv6_forward,
5648                 .owner =        THIS_MODULE,
5649                 .pf =           PF_INET6,
5650                 .hooknum =      NF_INET_FORWARD,
5651                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5652         }
5653 };
5654
5655 #endif  /* IPV6 */
5656
5657 static int __init selinux_nf_ip_init(void)
5658 {
5659         int err = 0;
5660
5661         if (!selinux_enabled)
5662                 goto out;
5663
5664         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5665
5666         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5667         if (err)
5668                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5669
5670 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5671         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5672         if (err)
5673                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5674 #endif  /* IPV6 */
5675
5676 out:
5677         return err;
5678 }
5679
5680 __initcall(selinux_nf_ip_init);
5681
5682 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5683 static void selinux_nf_ip_exit(void)
5684 {
5685         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5686
5687         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5688 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5689         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5690 #endif  /* IPV6 */
5691 }
5692 #endif
5693
5694 #else /* CONFIG_NETFILTER */
5695
5696 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5697 #define selinux_nf_ip_exit()
5698 #endif
5699
5700 #endif /* CONFIG_NETFILTER */
5701
5702 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5703 static int selinux_disabled;
5704
5705 int selinux_disable(void)
5706 {
5707         extern void exit_sel_fs(void);
5708
5709         if (ss_initialized) {
5710                 /* Not permitted after initial policy load. */
5711                 return -EINVAL;
5712         }
5713
5714         if (selinux_disabled) {
5715                 /* Only do this once. */
5716                 return -EINVAL;
5717         }
5718
5719         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5720
5721         selinux_disabled = 1;
5722         selinux_enabled = 0;
5723
5724         /* Reset security_ops to the secondary module, dummy or capability. */
5725         security_ops = secondary_ops;
5726
5727         /* Unregister netfilter hooks. */
5728         selinux_nf_ip_exit();
5729
5730         /* Unregister selinuxfs. */
5731         exit_sel_fs();
5732
5733         return 0;
5734 }
5735 #endif