Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[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 Red Hat, Inc., James Morris <jmorris@redhat.com>
13  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
14  *                          <dgoeddel@trustedcs.com>
15  *  Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
16  *                     Paul Moore, <paul.moore@hp.com>
17  *
18  *      This program is free software; you can redistribute it and/or modify
19  *      it under the terms of the GNU General Public License version 2,
20  *      as published by the Free Software Foundation.
21  */
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/kernel.h>
26 #include <linux/ptrace.h>
27 #include <linux/errno.h>
28 #include <linux/sched.h>
29 #include <linux/security.h>
30 #include <linux/xattr.h>
31 #include <linux/capability.h>
32 #include <linux/unistd.h>
33 #include <linux/mm.h>
34 #include <linux/mman.h>
35 #include <linux/slab.h>
36 #include <linux/pagemap.h>
37 #include <linux/swap.h>
38 #include <linux/smp_lock.h>
39 #include <linux/spinlock.h>
40 #include <linux/syscalls.h>
41 #include <linux/file.h>
42 #include <linux/namei.h>
43 #include <linux/mount.h>
44 #include <linux/ext2_fs.h>
45 #include <linux/proc_fs.h>
46 #include <linux/kd.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 sysctl_local_port_range[] */
52 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
53 #include <asm/uaccess.h>
54 #include <asm/ioctls.h>
55 #include <linux/bitops.h>
56 #include <linux/interrupt.h>
57 #include <linux/netdevice.h>    /* for network interface checks */
58 #include <linux/netlink.h>
59 #include <linux/tcp.h>
60 #include <linux/udp.h>
61 #include <linux/quota.h>
62 #include <linux/un.h>           /* for Unix socket types */
63 #include <net/af_unix.h>        /* for Unix socket types */
64 #include <linux/parser.h>
65 #include <linux/nfs_mount.h>
66 #include <net/ipv6.h>
67 #include <linux/hugetlb.h>
68 #include <linux/personality.h>
69 #include <linux/sysctl.h>
70 #include <linux/audit.h>
71 #include <linux/string.h>
72 #include <linux/selinux.h>
73 #include <linux/mutex.h>
74
75 #include "avc.h"
76 #include "objsec.h"
77 #include "netif.h"
78 #include "xfrm.h"
79 #include "selinux_netlabel.h"
80
81 #define XATTR_SELINUX_SUFFIX "selinux"
82 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
83
84 extern unsigned int policydb_loaded_version;
85 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
86 extern int selinux_compat_net;
87
88 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
89 int selinux_enforcing = 0;
90
91 static int __init enforcing_setup(char *str)
92 {
93         selinux_enforcing = simple_strtol(str,NULL,0);
94         return 1;
95 }
96 __setup("enforcing=", enforcing_setup);
97 #endif
98
99 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
100 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
101
102 static int __init selinux_enabled_setup(char *str)
103 {
104         selinux_enabled = simple_strtol(str, NULL, 0);
105         return 1;
106 }
107 __setup("selinux=", selinux_enabled_setup);
108 #else
109 int selinux_enabled = 1;
110 #endif
111
112 /* Original (dummy) security module. */
113 static struct security_operations *original_ops = NULL;
114
115 /* Minimal support for a secondary security module,
116    just to allow the use of the dummy or capability modules.
117    The owlsm module can alternatively be used as a secondary
118    module as long as CONFIG_OWLSM_FD is not enabled. */
119 static struct security_operations *secondary_ops = NULL;
120
121 /* Lists of inode and superblock security structures initialized
122    before the policy was loaded. */
123 static LIST_HEAD(superblock_security_head);
124 static DEFINE_SPINLOCK(sb_security_lock);
125
126 static kmem_cache_t *sel_inode_cache;
127
128 /* Return security context for a given sid or just the context 
129    length if the buffer is null or length is 0 */
130 static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
131 {
132         char *context;
133         unsigned len;
134         int rc;
135
136         rc = security_sid_to_context(sid, &context, &len);
137         if (rc)
138                 return rc;
139
140         if (!buffer || !size)
141                 goto getsecurity_exit;
142
143         if (size < len) {
144                 len = -ERANGE;
145                 goto getsecurity_exit;
146         }
147         memcpy(buffer, context, len);
148
149 getsecurity_exit:
150         kfree(context);
151         return len;
152 }
153
154 /* Allocate and free functions for each kind of security blob. */
155
156 static int task_alloc_security(struct task_struct *task)
157 {
158         struct task_security_struct *tsec;
159
160         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
161         if (!tsec)
162                 return -ENOMEM;
163
164         tsec->task = task;
165         tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
166         task->security = tsec;
167
168         return 0;
169 }
170
171 static void task_free_security(struct task_struct *task)
172 {
173         struct task_security_struct *tsec = task->security;
174         task->security = NULL;
175         kfree(tsec);
176 }
177
178 static int inode_alloc_security(struct inode *inode)
179 {
180         struct task_security_struct *tsec = current->security;
181         struct inode_security_struct *isec;
182
183         isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL);
184         if (!isec)
185                 return -ENOMEM;
186
187         memset(isec, 0, sizeof(*isec));
188         mutex_init(&isec->lock);
189         INIT_LIST_HEAD(&isec->list);
190         isec->inode = inode;
191         isec->sid = SECINITSID_UNLABELED;
192         isec->sclass = SECCLASS_FILE;
193         isec->task_sid = tsec->sid;
194         inode->i_security = isec;
195
196         return 0;
197 }
198
199 static void inode_free_security(struct inode *inode)
200 {
201         struct inode_security_struct *isec = inode->i_security;
202         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
203
204         spin_lock(&sbsec->isec_lock);
205         if (!list_empty(&isec->list))
206                 list_del_init(&isec->list);
207         spin_unlock(&sbsec->isec_lock);
208
209         inode->i_security = NULL;
210         kmem_cache_free(sel_inode_cache, isec);
211 }
212
213 static int file_alloc_security(struct file *file)
214 {
215         struct task_security_struct *tsec = current->security;
216         struct file_security_struct *fsec;
217
218         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
219         if (!fsec)
220                 return -ENOMEM;
221
222         fsec->file = file;
223         fsec->sid = tsec->sid;
224         fsec->fown_sid = tsec->sid;
225         file->f_security = fsec;
226
227         return 0;
228 }
229
230 static void file_free_security(struct file *file)
231 {
232         struct file_security_struct *fsec = file->f_security;
233         file->f_security = NULL;
234         kfree(fsec);
235 }
236
237 static int superblock_alloc_security(struct super_block *sb)
238 {
239         struct superblock_security_struct *sbsec;
240
241         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
242         if (!sbsec)
243                 return -ENOMEM;
244
245         mutex_init(&sbsec->lock);
246         INIT_LIST_HEAD(&sbsec->list);
247         INIT_LIST_HEAD(&sbsec->isec_head);
248         spin_lock_init(&sbsec->isec_lock);
249         sbsec->sb = sb;
250         sbsec->sid = SECINITSID_UNLABELED;
251         sbsec->def_sid = SECINITSID_FILE;
252         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
253         sb->s_security = sbsec;
254
255         return 0;
256 }
257
258 static void superblock_free_security(struct super_block *sb)
259 {
260         struct superblock_security_struct *sbsec = sb->s_security;
261
262         spin_lock(&sb_security_lock);
263         if (!list_empty(&sbsec->list))
264                 list_del_init(&sbsec->list);
265         spin_unlock(&sb_security_lock);
266
267         sb->s_security = NULL;
268         kfree(sbsec);
269 }
270
271 static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
272 {
273         struct sk_security_struct *ssec;
274
275         ssec = kzalloc(sizeof(*ssec), priority);
276         if (!ssec)
277                 return -ENOMEM;
278
279         ssec->sk = sk;
280         ssec->peer_sid = SECINITSID_UNLABELED;
281         ssec->sid = SECINITSID_UNLABELED;
282         sk->sk_security = ssec;
283
284         selinux_netlbl_sk_security_init(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_context = 1,
321         Opt_fscontext = 2,
322         Opt_defcontext = 4,
323         Opt_rootcontext = 8,
324 };
325
326 static match_table_t tokens = {
327         {Opt_context, "context=%s"},
328         {Opt_fscontext, "fscontext=%s"},
329         {Opt_defcontext, "defcontext=%s"},
330         {Opt_rootcontext, "rootcontext=%s"},
331 };
332
333 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
334
335 static int may_context_mount_sb_relabel(u32 sid,
336                         struct superblock_security_struct *sbsec,
337                         struct task_security_struct *tsec)
338 {
339         int rc;
340
341         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
342                           FILESYSTEM__RELABELFROM, NULL);
343         if (rc)
344                 return rc;
345
346         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
347                           FILESYSTEM__RELABELTO, NULL);
348         return rc;
349 }
350
351 static int may_context_mount_inode_relabel(u32 sid,
352                         struct superblock_security_struct *sbsec,
353                         struct task_security_struct *tsec)
354 {
355         int rc;
356         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
357                           FILESYSTEM__RELABELFROM, NULL);
358         if (rc)
359                 return rc;
360
361         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
362                           FILESYSTEM__ASSOCIATE, NULL);
363         return rc;
364 }
365
366 static int try_context_mount(struct super_block *sb, void *data)
367 {
368         char *context = NULL, *defcontext = NULL;
369         char *fscontext = NULL, *rootcontext = NULL;
370         const char *name;
371         u32 sid;
372         int alloc = 0, rc = 0, seen = 0;
373         struct task_security_struct *tsec = current->security;
374         struct superblock_security_struct *sbsec = sb->s_security;
375
376         if (!data)
377                 goto out;
378
379         name = sb->s_type->name;
380
381         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
382
383                 /* NFS we understand. */
384                 if (!strcmp(name, "nfs")) {
385                         struct nfs_mount_data *d = data;
386
387                         if (d->version <  NFS_MOUNT_VERSION)
388                                 goto out;
389
390                         if (d->context[0]) {
391                                 context = d->context;
392                                 seen |= Opt_context;
393                         }
394                 } else
395                         goto out;
396
397         } else {
398                 /* Standard string-based options. */
399                 char *p, *options = data;
400
401                 while ((p = strsep(&options, "|")) != NULL) {
402                         int token;
403                         substring_t args[MAX_OPT_ARGS];
404
405                         if (!*p)
406                                 continue;
407
408                         token = match_token(p, tokens, args);
409
410                         switch (token) {
411                         case Opt_context:
412                                 if (seen & (Opt_context|Opt_defcontext)) {
413                                         rc = -EINVAL;
414                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
415                                         goto out_free;
416                                 }
417                                 context = match_strdup(&args[0]);
418                                 if (!context) {
419                                         rc = -ENOMEM;
420                                         goto out_free;
421                                 }
422                                 if (!alloc)
423                                         alloc = 1;
424                                 seen |= Opt_context;
425                                 break;
426
427                         case Opt_fscontext:
428                                 if (seen & Opt_fscontext) {
429                                         rc = -EINVAL;
430                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
431                                         goto out_free;
432                                 }
433                                 fscontext = match_strdup(&args[0]);
434                                 if (!fscontext) {
435                                         rc = -ENOMEM;
436                                         goto out_free;
437                                 }
438                                 if (!alloc)
439                                         alloc = 1;
440                                 seen |= Opt_fscontext;
441                                 break;
442
443                         case Opt_rootcontext:
444                                 if (seen & Opt_rootcontext) {
445                                         rc = -EINVAL;
446                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
447                                         goto out_free;
448                                 }
449                                 rootcontext = match_strdup(&args[0]);
450                                 if (!rootcontext) {
451                                         rc = -ENOMEM;
452                                         goto out_free;
453                                 }
454                                 if (!alloc)
455                                         alloc = 1;
456                                 seen |= Opt_rootcontext;
457                                 break;
458
459                         case Opt_defcontext:
460                                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
461                                         rc = -EINVAL;
462                                         printk(KERN_WARNING "SELinux:  "
463                                                "defcontext option is invalid "
464                                                "for this filesystem type\n");
465                                         goto out_free;
466                                 }
467                                 if (seen & (Opt_context|Opt_defcontext)) {
468                                         rc = -EINVAL;
469                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
470                                         goto out_free;
471                                 }
472                                 defcontext = match_strdup(&args[0]);
473                                 if (!defcontext) {
474                                         rc = -ENOMEM;
475                                         goto out_free;
476                                 }
477                                 if (!alloc)
478                                         alloc = 1;
479                                 seen |= Opt_defcontext;
480                                 break;
481
482                         default:
483                                 rc = -EINVAL;
484                                 printk(KERN_WARNING "SELinux:  unknown mount "
485                                        "option\n");
486                                 goto out_free;
487
488                         }
489                 }
490         }
491
492         if (!seen)
493                 goto out;
494
495         /* sets the context of the superblock for the fs being mounted. */
496         if (fscontext) {
497                 rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
498                 if (rc) {
499                         printk(KERN_WARNING "SELinux: security_context_to_sid"
500                                "(%s) failed for (dev %s, type %s) errno=%d\n",
501                                fscontext, sb->s_id, name, rc);
502                         goto out_free;
503                 }
504
505                 rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
506                 if (rc)
507                         goto out_free;
508
509                 sbsec->sid = sid;
510         }
511
512         /*
513          * Switch to using mount point labeling behavior.
514          * sets the label used on all file below the mountpoint, and will set
515          * the superblock context if not already set.
516          */
517         if (context) {
518                 rc = security_context_to_sid(context, strlen(context), &sid);
519                 if (rc) {
520                         printk(KERN_WARNING "SELinux: security_context_to_sid"
521                                "(%s) failed for (dev %s, type %s) errno=%d\n",
522                                context, sb->s_id, name, rc);
523                         goto out_free;
524                 }
525
526                 if (!fscontext) {
527                         rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
528                         if (rc)
529                                 goto out_free;
530                         sbsec->sid = sid;
531                 } else {
532                         rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
533                         if (rc)
534                                 goto out_free;
535                 }
536                 sbsec->mntpoint_sid = sid;
537
538                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
539         }
540
541         if (rootcontext) {
542                 struct inode *inode = sb->s_root->d_inode;
543                 struct inode_security_struct *isec = inode->i_security;
544                 rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
545                 if (rc) {
546                         printk(KERN_WARNING "SELinux: security_context_to_sid"
547                                "(%s) failed for (dev %s, type %s) errno=%d\n",
548                                rootcontext, sb->s_id, name, rc);
549                         goto out_free;
550                 }
551
552                 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
553                 if (rc)
554                         goto out_free;
555
556                 isec->sid = sid;
557                 isec->initialized = 1;
558         }
559
560         if (defcontext) {
561                 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
562                 if (rc) {
563                         printk(KERN_WARNING "SELinux: security_context_to_sid"
564                                "(%s) failed for (dev %s, type %s) errno=%d\n",
565                                defcontext, sb->s_id, name, rc);
566                         goto out_free;
567                 }
568
569                 if (sid == sbsec->def_sid)
570                         goto out_free;
571
572                 rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
573                 if (rc)
574                         goto out_free;
575
576                 sbsec->def_sid = sid;
577         }
578
579 out_free:
580         if (alloc) {
581                 kfree(context);
582                 kfree(defcontext);
583                 kfree(fscontext);
584                 kfree(rootcontext);
585         }
586 out:
587         return rc;
588 }
589
590 static int superblock_doinit(struct super_block *sb, void *data)
591 {
592         struct superblock_security_struct *sbsec = sb->s_security;
593         struct dentry *root = sb->s_root;
594         struct inode *inode = root->d_inode;
595         int rc = 0;
596
597         mutex_lock(&sbsec->lock);
598         if (sbsec->initialized)
599                 goto out;
600
601         if (!ss_initialized) {
602                 /* Defer initialization until selinux_complete_init,
603                    after the initial policy is loaded and the security
604                    server is ready to handle calls. */
605                 spin_lock(&sb_security_lock);
606                 if (list_empty(&sbsec->list))
607                         list_add(&sbsec->list, &superblock_security_head);
608                 spin_unlock(&sb_security_lock);
609                 goto out;
610         }
611
612         /* Determine the labeling behavior to use for this filesystem type. */
613         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
614         if (rc) {
615                 printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
616                        __FUNCTION__, sb->s_type->name, rc);
617                 goto out;
618         }
619
620         rc = try_context_mount(sb, data);
621         if (rc)
622                 goto out;
623
624         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
625                 /* Make sure that the xattr handler exists and that no
626                    error other than -ENODATA is returned by getxattr on
627                    the root directory.  -ENODATA is ok, as this may be
628                    the first boot of the SELinux kernel before we have
629                    assigned xattr values to the filesystem. */
630                 if (!inode->i_op->getxattr) {
631                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
632                                "xattr support\n", sb->s_id, sb->s_type->name);
633                         rc = -EOPNOTSUPP;
634                         goto out;
635                 }
636                 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
637                 if (rc < 0 && rc != -ENODATA) {
638                         if (rc == -EOPNOTSUPP)
639                                 printk(KERN_WARNING "SELinux: (dev %s, type "
640                                        "%s) has no security xattr handler\n",
641                                        sb->s_id, sb->s_type->name);
642                         else
643                                 printk(KERN_WARNING "SELinux: (dev %s, type "
644                                        "%s) getxattr errno %d\n", sb->s_id,
645                                        sb->s_type->name, -rc);
646                         goto out;
647                 }
648         }
649
650         if (strcmp(sb->s_type->name, "proc") == 0)
651                 sbsec->proc = 1;
652
653         sbsec->initialized = 1;
654
655         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
656                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
657                        sb->s_id, sb->s_type->name);
658         }
659         else {
660                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
661                        sb->s_id, sb->s_type->name,
662                        labeling_behaviors[sbsec->behavior-1]);
663         }
664
665         /* Initialize the root inode. */
666         rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
667
668         /* Initialize any other inodes associated with the superblock, e.g.
669            inodes created prior to initial policy load or inodes created
670            during get_sb by a pseudo filesystem that directly
671            populates itself. */
672         spin_lock(&sbsec->isec_lock);
673 next_inode:
674         if (!list_empty(&sbsec->isec_head)) {
675                 struct inode_security_struct *isec =
676                                 list_entry(sbsec->isec_head.next,
677                                            struct inode_security_struct, list);
678                 struct inode *inode = isec->inode;
679                 spin_unlock(&sbsec->isec_lock);
680                 inode = igrab(inode);
681                 if (inode) {
682                         if (!IS_PRIVATE (inode))
683                                 inode_doinit(inode);
684                         iput(inode);
685                 }
686                 spin_lock(&sbsec->isec_lock);
687                 list_del_init(&isec->list);
688                 goto next_inode;
689         }
690         spin_unlock(&sbsec->isec_lock);
691 out:
692         mutex_unlock(&sbsec->lock);
693         return rc;
694 }
695
696 static inline u16 inode_mode_to_security_class(umode_t mode)
697 {
698         switch (mode & S_IFMT) {
699         case S_IFSOCK:
700                 return SECCLASS_SOCK_FILE;
701         case S_IFLNK:
702                 return SECCLASS_LNK_FILE;
703         case S_IFREG:
704                 return SECCLASS_FILE;
705         case S_IFBLK:
706                 return SECCLASS_BLK_FILE;
707         case S_IFDIR:
708                 return SECCLASS_DIR;
709         case S_IFCHR:
710                 return SECCLASS_CHR_FILE;
711         case S_IFIFO:
712                 return SECCLASS_FIFO_FILE;
713
714         }
715
716         return SECCLASS_FILE;
717 }
718
719 static inline int default_protocol_stream(int protocol)
720 {
721         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
722 }
723
724 static inline int default_protocol_dgram(int protocol)
725 {
726         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
727 }
728
729 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
730 {
731         switch (family) {
732         case PF_UNIX:
733                 switch (type) {
734                 case SOCK_STREAM:
735                 case SOCK_SEQPACKET:
736                         return SECCLASS_UNIX_STREAM_SOCKET;
737                 case SOCK_DGRAM:
738                         return SECCLASS_UNIX_DGRAM_SOCKET;
739                 }
740                 break;
741         case PF_INET:
742         case PF_INET6:
743                 switch (type) {
744                 case SOCK_STREAM:
745                         if (default_protocol_stream(protocol))
746                                 return SECCLASS_TCP_SOCKET;
747                         else
748                                 return SECCLASS_RAWIP_SOCKET;
749                 case SOCK_DGRAM:
750                         if (default_protocol_dgram(protocol))
751                                 return SECCLASS_UDP_SOCKET;
752                         else
753                                 return SECCLASS_RAWIP_SOCKET;
754                 default:
755                         return SECCLASS_RAWIP_SOCKET;
756                 }
757                 break;
758         case PF_NETLINK:
759                 switch (protocol) {
760                 case NETLINK_ROUTE:
761                         return SECCLASS_NETLINK_ROUTE_SOCKET;
762                 case NETLINK_FIREWALL:
763                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
764                 case NETLINK_INET_DIAG:
765                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
766                 case NETLINK_NFLOG:
767                         return SECCLASS_NETLINK_NFLOG_SOCKET;
768                 case NETLINK_XFRM:
769                         return SECCLASS_NETLINK_XFRM_SOCKET;
770                 case NETLINK_SELINUX:
771                         return SECCLASS_NETLINK_SELINUX_SOCKET;
772                 case NETLINK_AUDIT:
773                         return SECCLASS_NETLINK_AUDIT_SOCKET;
774                 case NETLINK_IP6_FW:
775                         return SECCLASS_NETLINK_IP6FW_SOCKET;
776                 case NETLINK_DNRTMSG:
777                         return SECCLASS_NETLINK_DNRT_SOCKET;
778                 case NETLINK_KOBJECT_UEVENT:
779                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
780                 default:
781                         return SECCLASS_NETLINK_SOCKET;
782                 }
783         case PF_PACKET:
784                 return SECCLASS_PACKET_SOCKET;
785         case PF_KEY:
786                 return SECCLASS_KEY_SOCKET;
787         case PF_APPLETALK:
788                 return SECCLASS_APPLETALK_SOCKET;
789         }
790
791         return SECCLASS_SOCKET;
792 }
793
794 #ifdef CONFIG_PROC_FS
795 static int selinux_proc_get_sid(struct proc_dir_entry *de,
796                                 u16 tclass,
797                                 u32 *sid)
798 {
799         int buflen, rc;
800         char *buffer, *path, *end;
801
802         buffer = (char*)__get_free_page(GFP_KERNEL);
803         if (!buffer)
804                 return -ENOMEM;
805
806         buflen = PAGE_SIZE;
807         end = buffer+buflen;
808         *--end = '\0';
809         buflen--;
810         path = end-1;
811         *path = '/';
812         while (de && de != de->parent) {
813                 buflen -= de->namelen + 1;
814                 if (buflen < 0)
815                         break;
816                 end -= de->namelen;
817                 memcpy(end, de->name, de->namelen);
818                 *--end = '/';
819                 path = end;
820                 de = de->parent;
821         }
822         rc = security_genfs_sid("proc", path, tclass, sid);
823         free_page((unsigned long)buffer);
824         return rc;
825 }
826 #else
827 static int selinux_proc_get_sid(struct proc_dir_entry *de,
828                                 u16 tclass,
829                                 u32 *sid)
830 {
831         return -EINVAL;
832 }
833 #endif
834
835 /* The inode's security attributes must be initialized before first use. */
836 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
837 {
838         struct superblock_security_struct *sbsec = NULL;
839         struct inode_security_struct *isec = inode->i_security;
840         u32 sid;
841         struct dentry *dentry;
842 #define INITCONTEXTLEN 255
843         char *context = NULL;
844         unsigned len = 0;
845         int rc = 0;
846
847         if (isec->initialized)
848                 goto out;
849
850         mutex_lock(&isec->lock);
851         if (isec->initialized)
852                 goto out_unlock;
853
854         sbsec = inode->i_sb->s_security;
855         if (!sbsec->initialized) {
856                 /* Defer initialization until selinux_complete_init,
857                    after the initial policy is loaded and the security
858                    server is ready to handle calls. */
859                 spin_lock(&sbsec->isec_lock);
860                 if (list_empty(&isec->list))
861                         list_add(&isec->list, &sbsec->isec_head);
862                 spin_unlock(&sbsec->isec_lock);
863                 goto out_unlock;
864         }
865
866         switch (sbsec->behavior) {
867         case SECURITY_FS_USE_XATTR:
868                 if (!inode->i_op->getxattr) {
869                         isec->sid = sbsec->def_sid;
870                         break;
871                 }
872
873                 /* Need a dentry, since the xattr API requires one.
874                    Life would be simpler if we could just pass the inode. */
875                 if (opt_dentry) {
876                         /* Called from d_instantiate or d_splice_alias. */
877                         dentry = dget(opt_dentry);
878                 } else {
879                         /* Called from selinux_complete_init, try to find a dentry. */
880                         dentry = d_find_alias(inode);
881                 }
882                 if (!dentry) {
883                         printk(KERN_WARNING "%s:  no dentry for dev=%s "
884                                "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
885                                inode->i_ino);
886                         goto out_unlock;
887                 }
888
889                 len = INITCONTEXTLEN;
890                 context = kmalloc(len, GFP_KERNEL);
891                 if (!context) {
892                         rc = -ENOMEM;
893                         dput(dentry);
894                         goto out_unlock;
895                 }
896                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
897                                            context, len);
898                 if (rc == -ERANGE) {
899                         /* Need a larger buffer.  Query for the right size. */
900                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
901                                                    NULL, 0);
902                         if (rc < 0) {
903                                 dput(dentry);
904                                 goto out_unlock;
905                         }
906                         kfree(context);
907                         len = rc;
908                         context = kmalloc(len, GFP_KERNEL);
909                         if (!context) {
910                                 rc = -ENOMEM;
911                                 dput(dentry);
912                                 goto out_unlock;
913                         }
914                         rc = inode->i_op->getxattr(dentry,
915                                                    XATTR_NAME_SELINUX,
916                                                    context, len);
917                 }
918                 dput(dentry);
919                 if (rc < 0) {
920                         if (rc != -ENODATA) {
921                                 printk(KERN_WARNING "%s:  getxattr returned "
922                                        "%d for dev=%s ino=%ld\n", __FUNCTION__,
923                                        -rc, inode->i_sb->s_id, inode->i_ino);
924                                 kfree(context);
925                                 goto out_unlock;
926                         }
927                         /* Map ENODATA to the default file SID */
928                         sid = sbsec->def_sid;
929                         rc = 0;
930                 } else {
931                         rc = security_context_to_sid_default(context, rc, &sid,
932                                                              sbsec->def_sid);
933                         if (rc) {
934                                 printk(KERN_WARNING "%s:  context_to_sid(%s) "
935                                        "returned %d for dev=%s ino=%ld\n",
936                                        __FUNCTION__, context, -rc,
937                                        inode->i_sb->s_id, inode->i_ino);
938                                 kfree(context);
939                                 /* Leave with the unlabeled SID */
940                                 rc = 0;
941                                 break;
942                         }
943                 }
944                 kfree(context);
945                 isec->sid = sid;
946                 break;
947         case SECURITY_FS_USE_TASK:
948                 isec->sid = isec->task_sid;
949                 break;
950         case SECURITY_FS_USE_TRANS:
951                 /* Default to the fs SID. */
952                 isec->sid = sbsec->sid;
953
954                 /* Try to obtain a transition SID. */
955                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
956                 rc = security_transition_sid(isec->task_sid,
957                                              sbsec->sid,
958                                              isec->sclass,
959                                              &sid);
960                 if (rc)
961                         goto out_unlock;
962                 isec->sid = sid;
963                 break;
964         case SECURITY_FS_USE_MNTPOINT:
965                 isec->sid = sbsec->mntpoint_sid;
966                 break;
967         default:
968                 /* Default to the fs superblock SID. */
969                 isec->sid = sbsec->sid;
970
971                 if (sbsec->proc) {
972                         struct proc_inode *proci = PROC_I(inode);
973                         if (proci->pde) {
974                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
975                                 rc = selinux_proc_get_sid(proci->pde,
976                                                           isec->sclass,
977                                                           &sid);
978                                 if (rc)
979                                         goto out_unlock;
980                                 isec->sid = sid;
981                         }
982                 }
983                 break;
984         }
985
986         isec->initialized = 1;
987
988 out_unlock:
989         mutex_unlock(&isec->lock);
990 out:
991         if (isec->sclass == SECCLASS_FILE)
992                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
993         return rc;
994 }
995
996 /* Convert a Linux signal to an access vector. */
997 static inline u32 signal_to_av(int sig)
998 {
999         u32 perm = 0;
1000
1001         switch (sig) {
1002         case SIGCHLD:
1003                 /* Commonly granted from child to parent. */
1004                 perm = PROCESS__SIGCHLD;
1005                 break;
1006         case SIGKILL:
1007                 /* Cannot be caught or ignored */
1008                 perm = PROCESS__SIGKILL;
1009                 break;
1010         case SIGSTOP:
1011                 /* Cannot be caught or ignored */
1012                 perm = PROCESS__SIGSTOP;
1013                 break;
1014         default:
1015                 /* All other signals. */
1016                 perm = PROCESS__SIGNAL;
1017                 break;
1018         }
1019
1020         return perm;
1021 }
1022
1023 /* Check permission betweeen a pair of tasks, e.g. signal checks,
1024    fork check, ptrace check, etc. */
1025 static int task_has_perm(struct task_struct *tsk1,
1026                          struct task_struct *tsk2,
1027                          u32 perms)
1028 {
1029         struct task_security_struct *tsec1, *tsec2;
1030
1031         tsec1 = tsk1->security;
1032         tsec2 = tsk2->security;
1033         return avc_has_perm(tsec1->sid, tsec2->sid,
1034                             SECCLASS_PROCESS, perms, NULL);
1035 }
1036
1037 /* Check whether a task is allowed to use a capability. */
1038 static int task_has_capability(struct task_struct *tsk,
1039                                int cap)
1040 {
1041         struct task_security_struct *tsec;
1042         struct avc_audit_data ad;
1043
1044         tsec = tsk->security;
1045
1046         AVC_AUDIT_DATA_INIT(&ad,CAP);
1047         ad.tsk = tsk;
1048         ad.u.cap = cap;
1049
1050         return avc_has_perm(tsec->sid, tsec->sid,
1051                             SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
1052 }
1053
1054 /* Check whether a task is allowed to use a system operation. */
1055 static int task_has_system(struct task_struct *tsk,
1056                            u32 perms)
1057 {
1058         struct task_security_struct *tsec;
1059
1060         tsec = tsk->security;
1061
1062         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
1063                             SECCLASS_SYSTEM, perms, NULL);
1064 }
1065
1066 /* Check whether a task has a particular permission to an inode.
1067    The 'adp' parameter is optional and allows other audit
1068    data to be passed (e.g. the dentry). */
1069 static int inode_has_perm(struct task_struct *tsk,
1070                           struct inode *inode,
1071                           u32 perms,
1072                           struct avc_audit_data *adp)
1073 {
1074         struct task_security_struct *tsec;
1075         struct inode_security_struct *isec;
1076         struct avc_audit_data ad;
1077
1078         tsec = tsk->security;
1079         isec = inode->i_security;
1080
1081         if (!adp) {
1082                 adp = &ad;
1083                 AVC_AUDIT_DATA_INIT(&ad, FS);
1084                 ad.u.fs.inode = inode;
1085         }
1086
1087         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
1088 }
1089
1090 /* Same as inode_has_perm, but pass explicit audit data containing
1091    the dentry to help the auditing code to more easily generate the
1092    pathname if needed. */
1093 static inline int dentry_has_perm(struct task_struct *tsk,
1094                                   struct vfsmount *mnt,
1095                                   struct dentry *dentry,
1096                                   u32 av)
1097 {
1098         struct inode *inode = dentry->d_inode;
1099         struct avc_audit_data ad;
1100         AVC_AUDIT_DATA_INIT(&ad,FS);
1101         ad.u.fs.mnt = mnt;
1102         ad.u.fs.dentry = dentry;
1103         return inode_has_perm(tsk, inode, av, &ad);
1104 }
1105
1106 /* Check whether a task can use an open file descriptor to
1107    access an inode in a given way.  Check access to the
1108    descriptor itself, and then use dentry_has_perm to
1109    check a particular permission to the file.
1110    Access to the descriptor is implicitly granted if it
1111    has the same SID as the process.  If av is zero, then
1112    access to the file is not checked, e.g. for cases
1113    where only the descriptor is affected like seek. */
1114 static int file_has_perm(struct task_struct *tsk,
1115                                 struct file *file,
1116                                 u32 av)
1117 {
1118         struct task_security_struct *tsec = tsk->security;
1119         struct file_security_struct *fsec = file->f_security;
1120         struct vfsmount *mnt = file->f_vfsmnt;
1121         struct dentry *dentry = file->f_dentry;
1122         struct inode *inode = dentry->d_inode;
1123         struct avc_audit_data ad;
1124         int rc;
1125
1126         AVC_AUDIT_DATA_INIT(&ad, FS);
1127         ad.u.fs.mnt = mnt;
1128         ad.u.fs.dentry = dentry;
1129
1130         if (tsec->sid != fsec->sid) {
1131                 rc = avc_has_perm(tsec->sid, fsec->sid,
1132                                   SECCLASS_FD,
1133                                   FD__USE,
1134                                   &ad);
1135                 if (rc)
1136                         return rc;
1137         }
1138
1139         /* av is zero if only checking access to the descriptor. */
1140         if (av)
1141                 return inode_has_perm(tsk, inode, av, &ad);
1142
1143         return 0;
1144 }
1145
1146 /* Check whether a task can create a file. */
1147 static int may_create(struct inode *dir,
1148                       struct dentry *dentry,
1149                       u16 tclass)
1150 {
1151         struct task_security_struct *tsec;
1152         struct inode_security_struct *dsec;
1153         struct superblock_security_struct *sbsec;
1154         u32 newsid;
1155         struct avc_audit_data ad;
1156         int rc;
1157
1158         tsec = current->security;
1159         dsec = dir->i_security;
1160         sbsec = dir->i_sb->s_security;
1161
1162         AVC_AUDIT_DATA_INIT(&ad, FS);
1163         ad.u.fs.dentry = dentry;
1164
1165         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1166                           DIR__ADD_NAME | DIR__SEARCH,
1167                           &ad);
1168         if (rc)
1169                 return rc;
1170
1171         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1172                 newsid = tsec->create_sid;
1173         } else {
1174                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1175                                              &newsid);
1176                 if (rc)
1177                         return rc;
1178         }
1179
1180         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1181         if (rc)
1182                 return rc;
1183
1184         return avc_has_perm(newsid, sbsec->sid,
1185                             SECCLASS_FILESYSTEM,
1186                             FILESYSTEM__ASSOCIATE, &ad);
1187 }
1188
1189 /* Check whether a task can create a key. */
1190 static int may_create_key(u32 ksid,
1191                           struct task_struct *ctx)
1192 {
1193         struct task_security_struct *tsec;
1194
1195         tsec = ctx->security;
1196
1197         return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1198 }
1199
1200 #define MAY_LINK   0
1201 #define MAY_UNLINK 1
1202 #define MAY_RMDIR  2
1203
1204 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1205 static int may_link(struct inode *dir,
1206                     struct dentry *dentry,
1207                     int kind)
1208
1209 {
1210         struct task_security_struct *tsec;
1211         struct inode_security_struct *dsec, *isec;
1212         struct avc_audit_data ad;
1213         u32 av;
1214         int rc;
1215
1216         tsec = current->security;
1217         dsec = dir->i_security;
1218         isec = dentry->d_inode->i_security;
1219
1220         AVC_AUDIT_DATA_INIT(&ad, FS);
1221         ad.u.fs.dentry = dentry;
1222
1223         av = DIR__SEARCH;
1224         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1225         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1226         if (rc)
1227                 return rc;
1228
1229         switch (kind) {
1230         case MAY_LINK:
1231                 av = FILE__LINK;
1232                 break;
1233         case MAY_UNLINK:
1234                 av = FILE__UNLINK;
1235                 break;
1236         case MAY_RMDIR:
1237                 av = DIR__RMDIR;
1238                 break;
1239         default:
1240                 printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1241                 return 0;
1242         }
1243
1244         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1245         return rc;
1246 }
1247
1248 static inline int may_rename(struct inode *old_dir,
1249                              struct dentry *old_dentry,
1250                              struct inode *new_dir,
1251                              struct dentry *new_dentry)
1252 {
1253         struct task_security_struct *tsec;
1254         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1255         struct avc_audit_data ad;
1256         u32 av;
1257         int old_is_dir, new_is_dir;
1258         int rc;
1259
1260         tsec = current->security;
1261         old_dsec = old_dir->i_security;
1262         old_isec = old_dentry->d_inode->i_security;
1263         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1264         new_dsec = new_dir->i_security;
1265
1266         AVC_AUDIT_DATA_INIT(&ad, FS);
1267
1268         ad.u.fs.dentry = old_dentry;
1269         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1270                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1271         if (rc)
1272                 return rc;
1273         rc = avc_has_perm(tsec->sid, old_isec->sid,
1274                           old_isec->sclass, FILE__RENAME, &ad);
1275         if (rc)
1276                 return rc;
1277         if (old_is_dir && new_dir != old_dir) {
1278                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1279                                   old_isec->sclass, DIR__REPARENT, &ad);
1280                 if (rc)
1281                         return rc;
1282         }
1283
1284         ad.u.fs.dentry = new_dentry;
1285         av = DIR__ADD_NAME | DIR__SEARCH;
1286         if (new_dentry->d_inode)
1287                 av |= DIR__REMOVE_NAME;
1288         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1289         if (rc)
1290                 return rc;
1291         if (new_dentry->d_inode) {
1292                 new_isec = new_dentry->d_inode->i_security;
1293                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1294                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1295                                   new_isec->sclass,
1296                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1297                 if (rc)
1298                         return rc;
1299         }
1300
1301         return 0;
1302 }
1303
1304 /* Check whether a task can perform a filesystem operation. */
1305 static int superblock_has_perm(struct task_struct *tsk,
1306                                struct super_block *sb,
1307                                u32 perms,
1308                                struct avc_audit_data *ad)
1309 {
1310         struct task_security_struct *tsec;
1311         struct superblock_security_struct *sbsec;
1312
1313         tsec = tsk->security;
1314         sbsec = sb->s_security;
1315         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1316                             perms, ad);
1317 }
1318
1319 /* Convert a Linux mode and permission mask to an access vector. */
1320 static inline u32 file_mask_to_av(int mode, int mask)
1321 {
1322         u32 av = 0;
1323
1324         if ((mode & S_IFMT) != S_IFDIR) {
1325                 if (mask & MAY_EXEC)
1326                         av |= FILE__EXECUTE;
1327                 if (mask & MAY_READ)
1328                         av |= FILE__READ;
1329
1330                 if (mask & MAY_APPEND)
1331                         av |= FILE__APPEND;
1332                 else if (mask & MAY_WRITE)
1333                         av |= FILE__WRITE;
1334
1335         } else {
1336                 if (mask & MAY_EXEC)
1337                         av |= DIR__SEARCH;
1338                 if (mask & MAY_WRITE)
1339                         av |= DIR__WRITE;
1340                 if (mask & MAY_READ)
1341                         av |= DIR__READ;
1342         }
1343
1344         return av;
1345 }
1346
1347 /* Convert a Linux file to an access vector. */
1348 static inline u32 file_to_av(struct file *file)
1349 {
1350         u32 av = 0;
1351
1352         if (file->f_mode & FMODE_READ)
1353                 av |= FILE__READ;
1354         if (file->f_mode & FMODE_WRITE) {
1355                 if (file->f_flags & O_APPEND)
1356                         av |= FILE__APPEND;
1357                 else
1358                         av |= FILE__WRITE;
1359         }
1360
1361         return av;
1362 }
1363
1364 /* Hook functions begin here. */
1365
1366 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1367 {
1368         struct task_security_struct *psec = parent->security;
1369         struct task_security_struct *csec = child->security;
1370         int rc;
1371
1372         rc = secondary_ops->ptrace(parent,child);
1373         if (rc)
1374                 return rc;
1375
1376         rc = task_has_perm(parent, child, PROCESS__PTRACE);
1377         /* Save the SID of the tracing process for later use in apply_creds. */
1378         if (!(child->ptrace & PT_PTRACED) && !rc)
1379                 csec->ptrace_sid = psec->sid;
1380         return rc;
1381 }
1382
1383 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1384                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1385 {
1386         int error;
1387
1388         error = task_has_perm(current, target, PROCESS__GETCAP);
1389         if (error)
1390                 return error;
1391
1392         return secondary_ops->capget(target, effective, inheritable, permitted);
1393 }
1394
1395 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1396                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1397 {
1398         int error;
1399
1400         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1401         if (error)
1402                 return error;
1403
1404         return task_has_perm(current, target, PROCESS__SETCAP);
1405 }
1406
1407 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1408                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1409 {
1410         secondary_ops->capset_set(target, effective, inheritable, permitted);
1411 }
1412
1413 static int selinux_capable(struct task_struct *tsk, int cap)
1414 {
1415         int rc;
1416
1417         rc = secondary_ops->capable(tsk, cap);
1418         if (rc)
1419                 return rc;
1420
1421         return task_has_capability(tsk,cap);
1422 }
1423
1424 static int selinux_sysctl(ctl_table *table, int op)
1425 {
1426         int error = 0;
1427         u32 av;
1428         struct task_security_struct *tsec;
1429         u32 tsid;
1430         int rc;
1431
1432         rc = secondary_ops->sysctl(table, op);
1433         if (rc)
1434                 return rc;
1435
1436         tsec = current->security;
1437
1438         rc = selinux_proc_get_sid(table->de, (op == 001) ?
1439                                   SECCLASS_DIR : SECCLASS_FILE, &tsid);
1440         if (rc) {
1441                 /* Default to the well-defined sysctl SID. */
1442                 tsid = SECINITSID_SYSCTL;
1443         }
1444
1445         /* The op values are "defined" in sysctl.c, thereby creating
1446          * a bad coupling between this module and sysctl.c */
1447         if(op == 001) {
1448                 error = avc_has_perm(tsec->sid, tsid,
1449                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1450         } else {
1451                 av = 0;
1452                 if (op & 004)
1453                         av |= FILE__READ;
1454                 if (op & 002)
1455                         av |= FILE__WRITE;
1456                 if (av)
1457                         error = avc_has_perm(tsec->sid, tsid,
1458                                              SECCLASS_FILE, av, NULL);
1459         }
1460
1461         return error;
1462 }
1463
1464 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1465 {
1466         int rc = 0;
1467
1468         if (!sb)
1469                 return 0;
1470
1471         switch (cmds) {
1472                 case Q_SYNC:
1473                 case Q_QUOTAON:
1474                 case Q_QUOTAOFF:
1475                 case Q_SETINFO:
1476                 case Q_SETQUOTA:
1477                         rc = superblock_has_perm(current,
1478                                                  sb,
1479                                                  FILESYSTEM__QUOTAMOD, NULL);
1480                         break;
1481                 case Q_GETFMT:
1482                 case Q_GETINFO:
1483                 case Q_GETQUOTA:
1484                         rc = superblock_has_perm(current,
1485                                                  sb,
1486                                                  FILESYSTEM__QUOTAGET, NULL);
1487                         break;
1488                 default:
1489                         rc = 0;  /* let the kernel handle invalid cmds */
1490                         break;
1491         }
1492         return rc;
1493 }
1494
1495 static int selinux_quota_on(struct dentry *dentry)
1496 {
1497         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1498 }
1499
1500 static int selinux_syslog(int type)
1501 {
1502         int rc;
1503
1504         rc = secondary_ops->syslog(type);
1505         if (rc)
1506                 return rc;
1507
1508         switch (type) {
1509                 case 3:         /* Read last kernel messages */
1510                 case 10:        /* Return size of the log buffer */
1511                         rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1512                         break;
1513                 case 6:         /* Disable logging to console */
1514                 case 7:         /* Enable logging to console */
1515                 case 8:         /* Set level of messages printed to console */
1516                         rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1517                         break;
1518                 case 0:         /* Close log */
1519                 case 1:         /* Open log */
1520                 case 2:         /* Read from log */
1521                 case 4:         /* Read/clear last kernel messages */
1522                 case 5:         /* Clear ring buffer */
1523                 default:
1524                         rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1525                         break;
1526         }
1527         return rc;
1528 }
1529
1530 /*
1531  * Check that a process has enough memory to allocate a new virtual
1532  * mapping. 0 means there is enough memory for the allocation to
1533  * succeed and -ENOMEM implies there is not.
1534  *
1535  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1536  * if the capability is granted, but __vm_enough_memory requires 1 if
1537  * the capability is granted.
1538  *
1539  * Do not audit the selinux permission check, as this is applied to all
1540  * processes that allocate mappings.
1541  */
1542 static int selinux_vm_enough_memory(long pages)
1543 {
1544         int rc, cap_sys_admin = 0;
1545         struct task_security_struct *tsec = current->security;
1546
1547         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1548         if (rc == 0)
1549                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1550                                         SECCLASS_CAPABILITY,
1551                                         CAP_TO_MASK(CAP_SYS_ADMIN),
1552                                         NULL);
1553
1554         if (rc == 0)
1555                 cap_sys_admin = 1;
1556
1557         return __vm_enough_memory(pages, cap_sys_admin);
1558 }
1559
1560 /* binprm security operations */
1561
1562 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1563 {
1564         struct bprm_security_struct *bsec;
1565
1566         bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1567         if (!bsec)
1568                 return -ENOMEM;
1569
1570         bsec->bprm = bprm;
1571         bsec->sid = SECINITSID_UNLABELED;
1572         bsec->set = 0;
1573
1574         bprm->security = bsec;
1575         return 0;
1576 }
1577
1578 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1579 {
1580         struct task_security_struct *tsec;
1581         struct inode *inode = bprm->file->f_dentry->d_inode;
1582         struct inode_security_struct *isec;
1583         struct bprm_security_struct *bsec;
1584         u32 newsid;
1585         struct avc_audit_data ad;
1586         int rc;
1587
1588         rc = secondary_ops->bprm_set_security(bprm);
1589         if (rc)
1590                 return rc;
1591
1592         bsec = bprm->security;
1593
1594         if (bsec->set)
1595                 return 0;
1596
1597         tsec = current->security;
1598         isec = inode->i_security;
1599
1600         /* Default to the current task SID. */
1601         bsec->sid = tsec->sid;
1602
1603         /* Reset fs, key, and sock SIDs on execve. */
1604         tsec->create_sid = 0;
1605         tsec->keycreate_sid = 0;
1606         tsec->sockcreate_sid = 0;
1607
1608         if (tsec->exec_sid) {
1609                 newsid = tsec->exec_sid;
1610                 /* Reset exec SID on execve. */
1611                 tsec->exec_sid = 0;
1612         } else {
1613                 /* Check for a default transition on this program. */
1614                 rc = security_transition_sid(tsec->sid, isec->sid,
1615                                              SECCLASS_PROCESS, &newsid);
1616                 if (rc)
1617                         return rc;
1618         }
1619
1620         AVC_AUDIT_DATA_INIT(&ad, FS);
1621         ad.u.fs.mnt = bprm->file->f_vfsmnt;
1622         ad.u.fs.dentry = bprm->file->f_dentry;
1623
1624         if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1625                 newsid = tsec->sid;
1626
1627         if (tsec->sid == newsid) {
1628                 rc = avc_has_perm(tsec->sid, isec->sid,
1629                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1630                 if (rc)
1631                         return rc;
1632         } else {
1633                 /* Check permissions for the transition. */
1634                 rc = avc_has_perm(tsec->sid, newsid,
1635                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1636                 if (rc)
1637                         return rc;
1638
1639                 rc = avc_has_perm(newsid, isec->sid,
1640                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1641                 if (rc)
1642                         return rc;
1643
1644                 /* Clear any possibly unsafe personality bits on exec: */
1645                 current->personality &= ~PER_CLEAR_ON_SETID;
1646
1647                 /* Set the security field to the new SID. */
1648                 bsec->sid = newsid;
1649         }
1650
1651         bsec->set = 1;
1652         return 0;
1653 }
1654
1655 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1656 {
1657         return secondary_ops->bprm_check_security(bprm);
1658 }
1659
1660
1661 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1662 {
1663         struct task_security_struct *tsec = current->security;
1664         int atsecure = 0;
1665
1666         if (tsec->osid != tsec->sid) {
1667                 /* Enable secure mode for SIDs transitions unless
1668                    the noatsecure permission is granted between
1669                    the two SIDs, i.e. ahp returns 0. */
1670                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1671                                          SECCLASS_PROCESS,
1672                                          PROCESS__NOATSECURE, NULL);
1673         }
1674
1675         return (atsecure || secondary_ops->bprm_secureexec(bprm));
1676 }
1677
1678 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1679 {
1680         kfree(bprm->security);
1681         bprm->security = NULL;
1682 }
1683
1684 extern struct vfsmount *selinuxfs_mount;
1685 extern struct dentry *selinux_null;
1686
1687 /* Derived from fs/exec.c:flush_old_files. */
1688 static inline void flush_unauthorized_files(struct files_struct * files)
1689 {
1690         struct avc_audit_data ad;
1691         struct file *file, *devnull = NULL;
1692         struct tty_struct *tty;
1693         struct fdtable *fdt;
1694         long j = -1;
1695
1696         mutex_lock(&tty_mutex);
1697         tty = current->signal->tty;
1698         if (tty) {
1699                 file_list_lock();
1700                 file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
1701                 if (file) {
1702                         /* Revalidate access to controlling tty.
1703                            Use inode_has_perm on the tty inode directly rather
1704                            than using file_has_perm, as this particular open
1705                            file may belong to another process and we are only
1706                            interested in the inode-based check here. */
1707                         struct inode *inode = file->f_dentry->d_inode;
1708                         if (inode_has_perm(current, inode,
1709                                            FILE__READ | FILE__WRITE, NULL)) {
1710                                 /* Reset controlling tty. */
1711                                 current->signal->tty = NULL;
1712                                 current->signal->tty_old_pgrp = 0;
1713                         }
1714                 }
1715                 file_list_unlock();
1716         }
1717         mutex_unlock(&tty_mutex);
1718
1719         /* Revalidate access to inherited open files. */
1720
1721         AVC_AUDIT_DATA_INIT(&ad,FS);
1722
1723         spin_lock(&files->file_lock);
1724         for (;;) {
1725                 unsigned long set, i;
1726                 int fd;
1727
1728                 j++;
1729                 i = j * __NFDBITS;
1730                 fdt = files_fdtable(files);
1731                 if (i >= fdt->max_fds || i >= fdt->max_fdset)
1732                         break;
1733                 set = fdt->open_fds->fds_bits[j];
1734                 if (!set)
1735                         continue;
1736                 spin_unlock(&files->file_lock);
1737                 for ( ; set ; i++,set >>= 1) {
1738                         if (set & 1) {
1739                                 file = fget(i);
1740                                 if (!file)
1741                                         continue;
1742                                 if (file_has_perm(current,
1743                                                   file,
1744                                                   file_to_av(file))) {
1745                                         sys_close(i);
1746                                         fd = get_unused_fd();
1747                                         if (fd != i) {
1748                                                 if (fd >= 0)
1749                                                         put_unused_fd(fd);
1750                                                 fput(file);
1751                                                 continue;
1752                                         }
1753                                         if (devnull) {
1754                                                 get_file(devnull);
1755                                         } else {
1756                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1757                                                 if (!devnull) {
1758                                                         put_unused_fd(fd);
1759                                                         fput(file);
1760                                                         continue;
1761                                                 }
1762                                         }
1763                                         fd_install(fd, devnull);
1764                                 }
1765                                 fput(file);
1766                         }
1767                 }
1768                 spin_lock(&files->file_lock);
1769
1770         }
1771         spin_unlock(&files->file_lock);
1772 }
1773
1774 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1775 {
1776         struct task_security_struct *tsec;
1777         struct bprm_security_struct *bsec;
1778         u32 sid;
1779         int rc;
1780
1781         secondary_ops->bprm_apply_creds(bprm, unsafe);
1782
1783         tsec = current->security;
1784
1785         bsec = bprm->security;
1786         sid = bsec->sid;
1787
1788         tsec->osid = tsec->sid;
1789         bsec->unsafe = 0;
1790         if (tsec->sid != sid) {
1791                 /* Check for shared state.  If not ok, leave SID
1792                    unchanged and kill. */
1793                 if (unsafe & LSM_UNSAFE_SHARE) {
1794                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1795                                         PROCESS__SHARE, NULL);
1796                         if (rc) {
1797                                 bsec->unsafe = 1;
1798                                 return;
1799                         }
1800                 }
1801
1802                 /* Check for ptracing, and update the task SID if ok.
1803                    Otherwise, leave SID unchanged and kill. */
1804                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1805                         rc = avc_has_perm(tsec->ptrace_sid, sid,
1806                                           SECCLASS_PROCESS, PROCESS__PTRACE,
1807                                           NULL);
1808                         if (rc) {
1809                                 bsec->unsafe = 1;
1810                                 return;
1811                         }
1812                 }
1813                 tsec->sid = sid;
1814         }
1815 }
1816
1817 /*
1818  * called after apply_creds without the task lock held
1819  */
1820 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1821 {
1822         struct task_security_struct *tsec;
1823         struct rlimit *rlim, *initrlim;
1824         struct itimerval itimer;
1825         struct bprm_security_struct *bsec;
1826         int rc, i;
1827
1828         tsec = current->security;
1829         bsec = bprm->security;
1830
1831         if (bsec->unsafe) {
1832                 force_sig_specific(SIGKILL, current);
1833                 return;
1834         }
1835         if (tsec->osid == tsec->sid)
1836                 return;
1837
1838         /* Close files for which the new task SID is not authorized. */
1839         flush_unauthorized_files(current->files);
1840
1841         /* Check whether the new SID can inherit signal state
1842            from the old SID.  If not, clear itimers to avoid
1843            subsequent signal generation and flush and unblock
1844            signals. This must occur _after_ the task SID has
1845           been updated so that any kill done after the flush
1846           will be checked against the new SID. */
1847         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1848                           PROCESS__SIGINH, NULL);
1849         if (rc) {
1850                 memset(&itimer, 0, sizeof itimer);
1851                 for (i = 0; i < 3; i++)
1852                         do_setitimer(i, &itimer, NULL);
1853                 flush_signals(current);
1854                 spin_lock_irq(&current->sighand->siglock);
1855                 flush_signal_handlers(current, 1);
1856                 sigemptyset(&current->blocked);
1857                 recalc_sigpending();
1858                 spin_unlock_irq(&current->sighand->siglock);
1859         }
1860
1861         /* Check whether the new SID can inherit resource limits
1862            from the old SID.  If not, reset all soft limits to
1863            the lower of the current task's hard limit and the init
1864            task's soft limit.  Note that the setting of hard limits
1865            (even to lower them) can be controlled by the setrlimit
1866            check. The inclusion of the init task's soft limit into
1867            the computation is to avoid resetting soft limits higher
1868            than the default soft limit for cases where the default
1869            is lower than the hard limit, e.g. RLIMIT_CORE or
1870            RLIMIT_STACK.*/
1871         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1872                           PROCESS__RLIMITINH, NULL);
1873         if (rc) {
1874                 for (i = 0; i < RLIM_NLIMITS; i++) {
1875                         rlim = current->signal->rlim + i;
1876                         initrlim = init_task.signal->rlim+i;
1877                         rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1878                 }
1879                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1880                         /*
1881                          * This will cause RLIMIT_CPU calculations
1882                          * to be refigured.
1883                          */
1884                         current->it_prof_expires = jiffies_to_cputime(1);
1885                 }
1886         }
1887
1888         /* Wake up the parent if it is waiting so that it can
1889            recheck wait permission to the new task SID. */
1890         wake_up_interruptible(&current->parent->signal->wait_chldexit);
1891 }
1892
1893 /* superblock security operations */
1894
1895 static int selinux_sb_alloc_security(struct super_block *sb)
1896 {
1897         return superblock_alloc_security(sb);
1898 }
1899
1900 static void selinux_sb_free_security(struct super_block *sb)
1901 {
1902         superblock_free_security(sb);
1903 }
1904
1905 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1906 {
1907         if (plen > olen)
1908                 return 0;
1909
1910         return !memcmp(prefix, option, plen);
1911 }
1912
1913 static inline int selinux_option(char *option, int len)
1914 {
1915         return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1916                 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1917                 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
1918                 match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
1919 }
1920
1921 static inline void take_option(char **to, char *from, int *first, int len)
1922 {
1923         if (!*first) {
1924                 **to = ',';
1925                 *to += 1;
1926         } else
1927                 *first = 0;
1928         memcpy(*to, from, len);
1929         *to += len;
1930 }
1931
1932 static inline void take_selinux_option(char **to, char *from, int *first, 
1933                                        int len)
1934 {
1935         int current_size = 0;
1936
1937         if (!*first) {
1938                 **to = '|';
1939                 *to += 1;
1940         }
1941         else
1942                 *first = 0;
1943
1944         while (current_size < len) {
1945                 if (*from != '"') {
1946                         **to = *from;
1947                         *to += 1;
1948                 }
1949                 from += 1;
1950                 current_size += 1;
1951         }
1952 }
1953
1954 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1955 {
1956         int fnosec, fsec, rc = 0;
1957         char *in_save, *in_curr, *in_end;
1958         char *sec_curr, *nosec_save, *nosec;
1959         int open_quote = 0;
1960
1961         in_curr = orig;
1962         sec_curr = copy;
1963
1964         /* Binary mount data: just copy */
1965         if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1966                 copy_page(sec_curr, in_curr);
1967                 goto out;
1968         }
1969
1970         nosec = (char *)get_zeroed_page(GFP_KERNEL);
1971         if (!nosec) {
1972                 rc = -ENOMEM;
1973                 goto out;
1974         }
1975
1976         nosec_save = nosec;
1977         fnosec = fsec = 1;
1978         in_save = in_end = orig;
1979
1980         do {
1981                 if (*in_end == '"')
1982                         open_quote = !open_quote;
1983                 if ((*in_end == ',' && open_quote == 0) ||
1984                                 *in_end == '\0') {
1985                         int len = in_end - in_curr;
1986
1987                         if (selinux_option(in_curr, len))
1988                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
1989                         else
1990                                 take_option(&nosec, in_curr, &fnosec, len);
1991
1992                         in_curr = in_end + 1;
1993                 }
1994         } while (*in_end++);
1995
1996         strcpy(in_save, nosec_save);
1997         free_page((unsigned long)nosec_save);
1998 out:
1999         return rc;
2000 }
2001
2002 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
2003 {
2004         struct avc_audit_data ad;
2005         int rc;
2006
2007         rc = superblock_doinit(sb, data);
2008         if (rc)
2009                 return rc;
2010
2011         AVC_AUDIT_DATA_INIT(&ad,FS);
2012         ad.u.fs.dentry = sb->s_root;
2013         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
2014 }
2015
2016 static int selinux_sb_statfs(struct dentry *dentry)
2017 {
2018         struct avc_audit_data ad;
2019
2020         AVC_AUDIT_DATA_INIT(&ad,FS);
2021         ad.u.fs.dentry = dentry->d_sb->s_root;
2022         return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2023 }
2024
2025 static int selinux_mount(char * dev_name,
2026                          struct nameidata *nd,
2027                          char * type,
2028                          unsigned long flags,
2029                          void * data)
2030 {
2031         int rc;
2032
2033         rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
2034         if (rc)
2035                 return rc;
2036
2037         if (flags & MS_REMOUNT)
2038                 return superblock_has_perm(current, nd->mnt->mnt_sb,
2039                                            FILESYSTEM__REMOUNT, NULL);
2040         else
2041                 return dentry_has_perm(current, nd->mnt, nd->dentry,
2042                                        FILE__MOUNTON);
2043 }
2044
2045 static int selinux_umount(struct vfsmount *mnt, int flags)
2046 {
2047         int rc;
2048
2049         rc = secondary_ops->sb_umount(mnt, flags);
2050         if (rc)
2051                 return rc;
2052
2053         return superblock_has_perm(current,mnt->mnt_sb,
2054                                    FILESYSTEM__UNMOUNT,NULL);
2055 }
2056
2057 /* inode security operations */
2058
2059 static int selinux_inode_alloc_security(struct inode *inode)
2060 {
2061         return inode_alloc_security(inode);
2062 }
2063
2064 static void selinux_inode_free_security(struct inode *inode)
2065 {
2066         inode_free_security(inode);
2067 }
2068
2069 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2070                                        char **name, void **value,
2071                                        size_t *len)
2072 {
2073         struct task_security_struct *tsec;
2074         struct inode_security_struct *dsec;
2075         struct superblock_security_struct *sbsec;
2076         u32 newsid, clen;
2077         int rc;
2078         char *namep = NULL, *context;
2079
2080         tsec = current->security;
2081         dsec = dir->i_security;
2082         sbsec = dir->i_sb->s_security;
2083
2084         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2085                 newsid = tsec->create_sid;
2086         } else {
2087                 rc = security_transition_sid(tsec->sid, dsec->sid,
2088                                              inode_mode_to_security_class(inode->i_mode),
2089                                              &newsid);
2090                 if (rc) {
2091                         printk(KERN_WARNING "%s:  "
2092                                "security_transition_sid failed, rc=%d (dev=%s "
2093                                "ino=%ld)\n",
2094                                __FUNCTION__,
2095                                -rc, inode->i_sb->s_id, inode->i_ino);
2096                         return rc;
2097                 }
2098         }
2099
2100         /* Possibly defer initialization to selinux_complete_init. */
2101         if (sbsec->initialized) {
2102                 struct inode_security_struct *isec = inode->i_security;
2103                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2104                 isec->sid = newsid;
2105                 isec->initialized = 1;
2106         }
2107
2108         if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2109                 return -EOPNOTSUPP;
2110
2111         if (name) {
2112                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL);
2113                 if (!namep)
2114                         return -ENOMEM;
2115                 *name = namep;
2116         }
2117
2118         if (value && len) {
2119                 rc = security_sid_to_context(newsid, &context, &clen);
2120                 if (rc) {
2121                         kfree(namep);
2122                         return rc;
2123                 }
2124                 *value = context;
2125                 *len = clen;
2126         }
2127
2128         return 0;
2129 }
2130
2131 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2132 {
2133         return may_create(dir, dentry, SECCLASS_FILE);
2134 }
2135
2136 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2137 {
2138         int rc;
2139
2140         rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2141         if (rc)
2142                 return rc;
2143         return may_link(dir, old_dentry, MAY_LINK);
2144 }
2145
2146 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2147 {
2148         int rc;
2149
2150         rc = secondary_ops->inode_unlink(dir, dentry);
2151         if (rc)
2152                 return rc;
2153         return may_link(dir, dentry, MAY_UNLINK);
2154 }
2155
2156 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2157 {
2158         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2159 }
2160
2161 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2162 {
2163         return may_create(dir, dentry, SECCLASS_DIR);
2164 }
2165
2166 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2167 {
2168         return may_link(dir, dentry, MAY_RMDIR);
2169 }
2170
2171 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2172 {
2173         int rc;
2174
2175         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2176         if (rc)
2177                 return rc;
2178
2179         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2180 }
2181
2182 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2183                                 struct inode *new_inode, struct dentry *new_dentry)
2184 {
2185         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2186 }
2187
2188 static int selinux_inode_readlink(struct dentry *dentry)
2189 {
2190         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2191 }
2192
2193 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2194 {
2195         int rc;
2196
2197         rc = secondary_ops->inode_follow_link(dentry,nameidata);
2198         if (rc)
2199                 return rc;
2200         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2201 }
2202
2203 static int selinux_inode_permission(struct inode *inode, int mask,
2204                                     struct nameidata *nd)
2205 {
2206         int rc;
2207
2208         rc = secondary_ops->inode_permission(inode, mask, nd);
2209         if (rc)
2210                 return rc;
2211
2212         if (!mask) {
2213                 /* No permission to check.  Existence test. */
2214                 return 0;
2215         }
2216
2217         return inode_has_perm(current, inode,
2218                                file_mask_to_av(inode->i_mode, mask), NULL);
2219 }
2220
2221 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2222 {
2223         int rc;
2224
2225         rc = secondary_ops->inode_setattr(dentry, iattr);
2226         if (rc)
2227                 return rc;
2228
2229         if (iattr->ia_valid & ATTR_FORCE)
2230                 return 0;
2231
2232         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2233                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2234                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2235
2236         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2237 }
2238
2239 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2240 {
2241         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2242 }
2243
2244 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2245 {
2246         struct task_security_struct *tsec = current->security;
2247         struct inode *inode = dentry->d_inode;
2248         struct inode_security_struct *isec = inode->i_security;
2249         struct superblock_security_struct *sbsec;
2250         struct avc_audit_data ad;
2251         u32 newsid;
2252         int rc = 0;
2253
2254         if (strcmp(name, XATTR_NAME_SELINUX)) {
2255                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2256                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2257                     !capable(CAP_SYS_ADMIN)) {
2258                         /* A different attribute in the security namespace.
2259                            Restrict to administrator. */
2260                         return -EPERM;
2261                 }
2262
2263                 /* Not an attribute we recognize, so just check the
2264                    ordinary setattr permission. */
2265                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2266         }
2267
2268         sbsec = inode->i_sb->s_security;
2269         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2270                 return -EOPNOTSUPP;
2271
2272         if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2273                 return -EPERM;
2274
2275         AVC_AUDIT_DATA_INIT(&ad,FS);
2276         ad.u.fs.dentry = dentry;
2277
2278         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2279                           FILE__RELABELFROM, &ad);
2280         if (rc)
2281                 return rc;
2282
2283         rc = security_context_to_sid(value, size, &newsid);
2284         if (rc)
2285                 return rc;
2286
2287         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2288                           FILE__RELABELTO, &ad);
2289         if (rc)
2290                 return rc;
2291
2292         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2293                                           isec->sclass);
2294         if (rc)
2295                 return rc;
2296
2297         return avc_has_perm(newsid,
2298                             sbsec->sid,
2299                             SECCLASS_FILESYSTEM,
2300                             FILESYSTEM__ASSOCIATE,
2301                             &ad);
2302 }
2303
2304 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2305                                         void *value, size_t size, int flags)
2306 {
2307         struct inode *inode = dentry->d_inode;
2308         struct inode_security_struct *isec = inode->i_security;
2309         u32 newsid;
2310         int rc;
2311
2312         if (strcmp(name, XATTR_NAME_SELINUX)) {
2313                 /* Not an attribute we recognize, so nothing to do. */
2314                 return;
2315         }
2316
2317         rc = security_context_to_sid(value, size, &newsid);
2318         if (rc) {
2319                 printk(KERN_WARNING "%s:  unable to obtain SID for context "
2320                        "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2321                 return;
2322         }
2323
2324         isec->sid = newsid;
2325         return;
2326 }
2327
2328 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2329 {
2330         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2331 }
2332
2333 static int selinux_inode_listxattr (struct dentry *dentry)
2334 {
2335         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2336 }
2337
2338 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2339 {
2340         if (strcmp(name, XATTR_NAME_SELINUX)) {
2341                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2342                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2343                     !capable(CAP_SYS_ADMIN)) {
2344                         /* A different attribute in the security namespace.
2345                            Restrict to administrator. */
2346                         return -EPERM;
2347                 }
2348
2349                 /* Not an attribute we recognize, so just check the
2350                    ordinary setattr permission. Might want a separate
2351                    permission for removexattr. */
2352                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2353         }
2354
2355         /* No one is allowed to remove a SELinux security label.
2356            You can change the label, but all data must be labeled. */
2357         return -EACCES;
2358 }
2359
2360 static const char *selinux_inode_xattr_getsuffix(void)
2361 {
2362       return XATTR_SELINUX_SUFFIX;
2363 }
2364
2365 /*
2366  * Copy the in-core inode security context value to the user.  If the
2367  * getxattr() prior to this succeeded, check to see if we need to
2368  * canonicalize the value to be finally returned to the user.
2369  *
2370  * Permission check is handled by selinux_inode_getxattr hook.
2371  */
2372 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
2373 {
2374         struct inode_security_struct *isec = inode->i_security;
2375
2376         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2377                 return -EOPNOTSUPP;
2378
2379         return selinux_getsecurity(isec->sid, buffer, size);
2380 }
2381
2382 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2383                                      const void *value, size_t size, int flags)
2384 {
2385         struct inode_security_struct *isec = inode->i_security;
2386         u32 newsid;
2387         int rc;
2388
2389         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2390                 return -EOPNOTSUPP;
2391
2392         if (!value || !size)
2393                 return -EACCES;
2394
2395         rc = security_context_to_sid((void*)value, size, &newsid);
2396         if (rc)
2397                 return rc;
2398
2399         isec->sid = newsid;
2400         return 0;
2401 }
2402
2403 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2404 {
2405         const int len = sizeof(XATTR_NAME_SELINUX);
2406         if (buffer && len <= buffer_size)
2407                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2408         return len;
2409 }
2410
2411 /* file security operations */
2412
2413 static int selinux_file_permission(struct file *file, int mask)
2414 {
2415         int rc;
2416         struct inode *inode = file->f_dentry->d_inode;
2417
2418         if (!mask) {
2419                 /* No permission to check.  Existence test. */
2420                 return 0;
2421         }
2422
2423         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2424         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2425                 mask |= MAY_APPEND;
2426
2427         rc = file_has_perm(current, file,
2428                            file_mask_to_av(inode->i_mode, mask));
2429         if (rc)
2430                 return rc;
2431
2432         return selinux_netlbl_inode_permission(inode, mask);
2433 }
2434
2435 static int selinux_file_alloc_security(struct file *file)
2436 {
2437         return file_alloc_security(file);
2438 }
2439
2440 static void selinux_file_free_security(struct file *file)
2441 {
2442         file_free_security(file);
2443 }
2444
2445 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2446                               unsigned long arg)
2447 {
2448         int error = 0;
2449
2450         switch (cmd) {
2451                 case FIONREAD:
2452                 /* fall through */
2453                 case FIBMAP:
2454                 /* fall through */
2455                 case FIGETBSZ:
2456                 /* fall through */
2457                 case EXT2_IOC_GETFLAGS:
2458                 /* fall through */
2459                 case EXT2_IOC_GETVERSION:
2460                         error = file_has_perm(current, file, FILE__GETATTR);
2461                         break;
2462
2463                 case EXT2_IOC_SETFLAGS:
2464                 /* fall through */
2465                 case EXT2_IOC_SETVERSION:
2466                         error = file_has_perm(current, file, FILE__SETATTR);
2467                         break;
2468
2469                 /* sys_ioctl() checks */
2470                 case FIONBIO:
2471                 /* fall through */
2472                 case FIOASYNC:
2473                         error = file_has_perm(current, file, 0);
2474                         break;
2475
2476                 case KDSKBENT:
2477                 case KDSKBSENT:
2478                         error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2479                         break;
2480
2481                 /* default case assumes that the command will go
2482                  * to the file's ioctl() function.
2483                  */
2484                 default:
2485                         error = file_has_perm(current, file, FILE__IOCTL);
2486
2487         }
2488         return error;
2489 }
2490
2491 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2492 {
2493 #ifndef CONFIG_PPC32
2494         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2495                 /*
2496                  * We are making executable an anonymous mapping or a
2497                  * private file mapping that will also be writable.
2498                  * This has an additional check.
2499                  */
2500                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2501                 if (rc)
2502                         return rc;
2503         }
2504 #endif
2505
2506         if (file) {
2507                 /* read access is always possible with a mapping */
2508                 u32 av = FILE__READ;
2509
2510                 /* write access only matters if the mapping is shared */
2511                 if (shared && (prot & PROT_WRITE))
2512                         av |= FILE__WRITE;
2513
2514                 if (prot & PROT_EXEC)
2515                         av |= FILE__EXECUTE;
2516
2517                 return file_has_perm(current, file, av);
2518         }
2519         return 0;
2520 }
2521
2522 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2523                              unsigned long prot, unsigned long flags)
2524 {
2525         int rc;
2526
2527         rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2528         if (rc)
2529                 return rc;
2530
2531         if (selinux_checkreqprot)
2532                 prot = reqprot;
2533
2534         return file_map_prot_check(file, prot,
2535                                    (flags & MAP_TYPE) == MAP_SHARED);
2536 }
2537
2538 static int selinux_file_mprotect(struct vm_area_struct *vma,
2539                                  unsigned long reqprot,
2540                                  unsigned long prot)
2541 {
2542         int rc;
2543
2544         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2545         if (rc)
2546                 return rc;
2547
2548         if (selinux_checkreqprot)
2549                 prot = reqprot;
2550
2551 #ifndef CONFIG_PPC32
2552         if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
2553                 rc = 0;
2554                 if (vma->vm_start >= vma->vm_mm->start_brk &&
2555                     vma->vm_end <= vma->vm_mm->brk) {
2556                         rc = task_has_perm(current, current,
2557                                            PROCESS__EXECHEAP);
2558                 } else if (!vma->vm_file &&
2559                            vma->vm_start <= vma->vm_mm->start_stack &&
2560                            vma->vm_end >= vma->vm_mm->start_stack) {
2561                         rc = task_has_perm(current, current, PROCESS__EXECSTACK);
2562                 } else if (vma->vm_file && vma->anon_vma) {
2563                         /*
2564                          * We are making executable a file mapping that has
2565                          * had some COW done. Since pages might have been
2566                          * written, check ability to execute the possibly
2567                          * modified content.  This typically should only
2568                          * occur for text relocations.
2569                          */
2570                         rc = file_has_perm(current, vma->vm_file,
2571                                            FILE__EXECMOD);
2572                 }
2573                 if (rc)
2574                         return rc;
2575         }
2576 #endif
2577
2578         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2579 }
2580
2581 static int selinux_file_lock(struct file *file, unsigned int cmd)
2582 {
2583         return file_has_perm(current, file, FILE__LOCK);
2584 }
2585
2586 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2587                               unsigned long arg)
2588 {
2589         int err = 0;
2590
2591         switch (cmd) {
2592                 case F_SETFL:
2593                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2594                                 err = -EINVAL;
2595                                 break;
2596                         }
2597
2598                         if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2599                                 err = file_has_perm(current, file,FILE__WRITE);
2600                                 break;
2601                         }
2602                         /* fall through */
2603                 case F_SETOWN:
2604                 case F_SETSIG:
2605                 case F_GETFL:
2606                 case F_GETOWN:
2607                 case F_GETSIG:
2608                         /* Just check FD__USE permission */
2609                         err = file_has_perm(current, file, 0);
2610                         break;
2611                 case F_GETLK:
2612                 case F_SETLK:
2613                 case F_SETLKW:
2614 #if BITS_PER_LONG == 32
2615                 case F_GETLK64:
2616                 case F_SETLK64:
2617                 case F_SETLKW64:
2618 #endif
2619                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2620                                 err = -EINVAL;
2621                                 break;
2622                         }
2623                         err = file_has_perm(current, file, FILE__LOCK);
2624                         break;
2625         }
2626
2627         return err;
2628 }
2629
2630 static int selinux_file_set_fowner(struct file *file)
2631 {
2632         struct task_security_struct *tsec;
2633         struct file_security_struct *fsec;
2634
2635         tsec = current->security;
2636         fsec = file->f_security;
2637         fsec->fown_sid = tsec->sid;
2638
2639         return 0;
2640 }
2641
2642 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2643                                        struct fown_struct *fown, int signum)
2644 {
2645         struct file *file;
2646         u32 perm;
2647         struct task_security_struct *tsec;
2648         struct file_security_struct *fsec;
2649
2650         /* struct fown_struct is never outside the context of a struct file */
2651         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2652
2653         tsec = tsk->security;
2654         fsec = file->f_security;
2655
2656         if (!signum)
2657                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2658         else
2659                 perm = signal_to_av(signum);
2660
2661         return avc_has_perm(fsec->fown_sid, tsec->sid,
2662                             SECCLASS_PROCESS, perm, NULL);
2663 }
2664
2665 static int selinux_file_receive(struct file *file)
2666 {
2667         return file_has_perm(current, file, file_to_av(file));
2668 }
2669
2670 /* task security operations */
2671
2672 static int selinux_task_create(unsigned long clone_flags)
2673 {
2674         int rc;
2675
2676         rc = secondary_ops->task_create(clone_flags);
2677         if (rc)
2678                 return rc;
2679
2680         return task_has_perm(current, current, PROCESS__FORK);
2681 }
2682
2683 static int selinux_task_alloc_security(struct task_struct *tsk)
2684 {
2685         struct task_security_struct *tsec1, *tsec2;
2686         int rc;
2687
2688         tsec1 = current->security;
2689
2690         rc = task_alloc_security(tsk);
2691         if (rc)
2692                 return rc;
2693         tsec2 = tsk->security;
2694
2695         tsec2->osid = tsec1->osid;
2696         tsec2->sid = tsec1->sid;
2697
2698         /* Retain the exec, fs, key, and sock SIDs across fork */
2699         tsec2->exec_sid = tsec1->exec_sid;
2700         tsec2->create_sid = tsec1->create_sid;
2701         tsec2->keycreate_sid = tsec1->keycreate_sid;
2702         tsec2->sockcreate_sid = tsec1->sockcreate_sid;
2703
2704         /* Retain ptracer SID across fork, if any.
2705            This will be reset by the ptrace hook upon any
2706            subsequent ptrace_attach operations. */
2707         tsec2->ptrace_sid = tsec1->ptrace_sid;
2708
2709         return 0;
2710 }
2711
2712 static void selinux_task_free_security(struct task_struct *tsk)
2713 {
2714         task_free_security(tsk);
2715 }
2716
2717 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2718 {
2719         /* Since setuid only affects the current process, and
2720            since the SELinux controls are not based on the Linux
2721            identity attributes, SELinux does not need to control
2722            this operation.  However, SELinux does control the use
2723            of the CAP_SETUID and CAP_SETGID capabilities using the
2724            capable hook. */
2725         return 0;
2726 }
2727
2728 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2729 {
2730         return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2731 }
2732
2733 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2734 {
2735         /* See the comment for setuid above. */
2736         return 0;
2737 }
2738
2739 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2740 {
2741         return task_has_perm(current, p, PROCESS__SETPGID);
2742 }
2743
2744 static int selinux_task_getpgid(struct task_struct *p)
2745 {
2746         return task_has_perm(current, p, PROCESS__GETPGID);
2747 }
2748
2749 static int selinux_task_getsid(struct task_struct *p)
2750 {
2751         return task_has_perm(current, p, PROCESS__GETSESSION);
2752 }
2753
2754 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
2755 {
2756         selinux_get_task_sid(p, secid);
2757 }
2758
2759 static int selinux_task_setgroups(struct group_info *group_info)
2760 {
2761         /* See the comment for setuid above. */
2762         return 0;
2763 }
2764
2765 static int selinux_task_setnice(struct task_struct *p, int nice)
2766 {
2767         int rc;
2768
2769         rc = secondary_ops->task_setnice(p, nice);
2770         if (rc)
2771                 return rc;
2772
2773         return task_has_perm(current,p, PROCESS__SETSCHED);
2774 }
2775
2776 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
2777 {
2778         return task_has_perm(current, p, PROCESS__SETSCHED);
2779 }
2780
2781 static int selinux_task_getioprio(struct task_struct *p)
2782 {
2783         return task_has_perm(current, p, PROCESS__GETSCHED);
2784 }
2785
2786 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2787 {
2788         struct rlimit *old_rlim = current->signal->rlim + resource;
2789         int rc;
2790
2791         rc = secondary_ops->task_setrlimit(resource, new_rlim);
2792         if (rc)
2793                 return rc;
2794
2795         /* Control the ability to change the hard limit (whether
2796            lowering or raising it), so that the hard limit can
2797            later be used as a safe reset point for the soft limit
2798            upon context transitions. See selinux_bprm_apply_creds. */
2799         if (old_rlim->rlim_max != new_rlim->rlim_max)
2800                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
2801
2802         return 0;
2803 }
2804
2805 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2806 {
2807         return task_has_perm(current, p, PROCESS__SETSCHED);
2808 }
2809
2810 static int selinux_task_getscheduler(struct task_struct *p)
2811 {
2812         return task_has_perm(current, p, PROCESS__GETSCHED);
2813 }
2814
2815 static int selinux_task_movememory(struct task_struct *p)
2816 {
2817         return task_has_perm(current, p, PROCESS__SETSCHED);
2818 }
2819
2820 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
2821                                 int sig, u32 secid)
2822 {
2823         u32 perm;
2824         int rc;
2825         struct task_security_struct *tsec;
2826
2827         rc = secondary_ops->task_kill(p, info, sig, secid);
2828         if (rc)
2829                 return rc;
2830
2831         if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
2832                 return 0;
2833
2834         if (!sig)
2835                 perm = PROCESS__SIGNULL; /* null signal; existence test */
2836         else
2837                 perm = signal_to_av(sig);
2838         tsec = p->security;
2839         if (secid)
2840                 rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
2841         else
2842                 rc = task_has_perm(current, p, perm);
2843         return rc;
2844 }
2845
2846 static int selinux_task_prctl(int option,
2847                               unsigned long arg2,
2848                               unsigned long arg3,
2849                               unsigned long arg4,
2850                               unsigned long arg5)
2851 {
2852         /* The current prctl operations do not appear to require
2853            any SELinux controls since they merely observe or modify
2854            the state of the current process. */
2855         return 0;
2856 }
2857
2858 static int selinux_task_wait(struct task_struct *p)
2859 {
2860         u32 perm;
2861
2862         perm = signal_to_av(p->exit_signal);
2863
2864         return task_has_perm(p, current, perm);
2865 }
2866
2867 static void selinux_task_reparent_to_init(struct task_struct *p)
2868 {
2869         struct task_security_struct *tsec;
2870
2871         secondary_ops->task_reparent_to_init(p);
2872
2873         tsec = p->security;
2874         tsec->osid = tsec->sid;
2875         tsec->sid = SECINITSID_KERNEL;
2876         return;
2877 }
2878
2879 static void selinux_task_to_inode(struct task_struct *p,
2880                                   struct inode *inode)
2881 {
2882         struct task_security_struct *tsec = p->security;
2883         struct inode_security_struct *isec = inode->i_security;
2884
2885         isec->sid = tsec->sid;
2886         isec->initialized = 1;
2887         return;
2888 }
2889
2890 /* Returns error only if unable to parse addresses */
2891 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2892 {
2893         int offset, ihlen, ret = -EINVAL;
2894         struct iphdr _iph, *ih;
2895
2896         offset = skb->nh.raw - skb->data;
2897         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2898         if (ih == NULL)
2899                 goto out;
2900
2901         ihlen = ih->ihl * 4;
2902         if (ihlen < sizeof(_iph))
2903                 goto out;
2904
2905         ad->u.net.v4info.saddr = ih->saddr;
2906         ad->u.net.v4info.daddr = ih->daddr;
2907         ret = 0;
2908
2909         switch (ih->protocol) {
2910         case IPPROTO_TCP: {
2911                 struct tcphdr _tcph, *th;
2912
2913                 if (ntohs(ih->frag_off) & IP_OFFSET)
2914                         break;
2915
2916                 offset += ihlen;
2917                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2918                 if (th == NULL)
2919                         break;
2920
2921                 ad->u.net.sport = th->source;
2922                 ad->u.net.dport = th->dest;
2923                 break;
2924         }
2925         
2926         case IPPROTO_UDP: {
2927                 struct udphdr _udph, *uh;
2928                 
2929                 if (ntohs(ih->frag_off) & IP_OFFSET)
2930                         break;
2931                         
2932                 offset += ihlen;
2933                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2934                 if (uh == NULL)
2935                         break;  
2936
2937                 ad->u.net.sport = uh->source;
2938                 ad->u.net.dport = uh->dest;
2939                 break;
2940         }
2941
2942         default:
2943                 break;
2944         }
2945 out:
2946         return ret;
2947 }
2948
2949 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2950
2951 /* Returns error only if unable to parse addresses */
2952 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2953 {
2954         u8 nexthdr;
2955         int ret = -EINVAL, offset;
2956         struct ipv6hdr _ipv6h, *ip6;
2957
2958         offset = skb->nh.raw - skb->data;
2959         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2960         if (ip6 == NULL)
2961                 goto out;
2962
2963         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2964         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2965         ret = 0;
2966
2967         nexthdr = ip6->nexthdr;
2968         offset += sizeof(_ipv6h);
2969         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2970         if (offset < 0)
2971                 goto out;
2972
2973         switch (nexthdr) {
2974         case IPPROTO_TCP: {
2975                 struct tcphdr _tcph, *th;
2976
2977                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2978                 if (th == NULL)
2979                         break;
2980
2981                 ad->u.net.sport = th->source;
2982                 ad->u.net.dport = th->dest;
2983                 break;
2984         }
2985
2986         case IPPROTO_UDP: {
2987                 struct udphdr _udph, *uh;
2988
2989                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2990                 if (uh == NULL)
2991                         break;
2992
2993                 ad->u.net.sport = uh->source;
2994                 ad->u.net.dport = uh->dest;
2995                 break;
2996         }
2997
2998         /* includes fragments */
2999         default:
3000                 break;
3001         }
3002 out:
3003         return ret;
3004 }
3005
3006 #endif /* IPV6 */
3007
3008 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3009                              char **addrp, int *len, int src)
3010 {
3011         int ret = 0;
3012
3013         switch (ad->u.net.family) {
3014         case PF_INET:
3015                 ret = selinux_parse_skb_ipv4(skb, ad);
3016                 if (ret || !addrp)
3017                         break;
3018                 *len = 4;
3019                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3020                                         &ad->u.net.v4info.daddr);
3021                 break;
3022
3023 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3024         case PF_INET6:
3025                 ret = selinux_parse_skb_ipv6(skb, ad);
3026                 if (ret || !addrp)
3027                         break;
3028                 *len = 16;
3029                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3030                                         &ad->u.net.v6info.daddr);
3031                 break;
3032 #endif  /* IPV6 */
3033         default:
3034                 break;
3035         }
3036
3037         return ret;
3038 }
3039
3040 /* socket security operations */
3041 static int socket_has_perm(struct task_struct *task, struct socket *sock,
3042                            u32 perms)
3043 {
3044         struct inode_security_struct *isec;
3045         struct task_security_struct *tsec;
3046         struct avc_audit_data ad;
3047         int err = 0;
3048
3049         tsec = task->security;
3050         isec = SOCK_INODE(sock)->i_security;
3051
3052         if (isec->sid == SECINITSID_KERNEL)
3053                 goto out;
3054
3055         AVC_AUDIT_DATA_INIT(&ad,NET);
3056         ad.u.net.sk = sock->sk;
3057         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
3058
3059 out:
3060         return err;
3061 }
3062
3063 static int selinux_socket_create(int family, int type,
3064                                  int protocol, int kern)
3065 {
3066         int err = 0;
3067         struct task_security_struct *tsec;
3068         u32 newsid;
3069
3070         if (kern)
3071                 goto out;
3072
3073         tsec = current->security;
3074         newsid = tsec->sockcreate_sid ? : tsec->sid;
3075         err = avc_has_perm(tsec->sid, newsid,
3076                            socket_type_to_security_class(family, type,
3077                            protocol), SOCKET__CREATE, NULL);
3078
3079 out:
3080         return err;
3081 }
3082
3083 static int selinux_socket_post_create(struct socket *sock, int family,
3084                                       int type, int protocol, int kern)
3085 {
3086         int err = 0;
3087         struct inode_security_struct *isec;
3088         struct task_security_struct *tsec;
3089         struct sk_security_struct *sksec;
3090         u32 newsid;
3091
3092         isec = SOCK_INODE(sock)->i_security;
3093
3094         tsec = current->security;
3095         newsid = tsec->sockcreate_sid ? : tsec->sid;
3096         isec->sclass = socket_type_to_security_class(family, type, protocol);
3097         isec->sid = kern ? SECINITSID_KERNEL : newsid;
3098         isec->initialized = 1;
3099
3100         if (sock->sk) {
3101                 sksec = sock->sk->sk_security;
3102                 sksec->sid = isec->sid;
3103                 err = selinux_netlbl_socket_post_create(sock,
3104                                                         family,
3105                                                         isec->sid);
3106         }
3107
3108         return err;
3109 }
3110
3111 /* Range of port numbers used to automatically bind.
3112    Need to determine whether we should perform a name_bind
3113    permission check between the socket and the port number. */
3114 #define ip_local_port_range_0 sysctl_local_port_range[0]
3115 #define ip_local_port_range_1 sysctl_local_port_range[1]
3116
3117 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3118 {
3119         u16 family;
3120         int err;
3121
3122         err = socket_has_perm(current, sock, SOCKET__BIND);
3123         if (err)
3124                 goto out;
3125
3126         /*
3127          * If PF_INET or PF_INET6, check name_bind permission for the port.
3128          * Multiple address binding for SCTP is not supported yet: we just
3129          * check the first address now.
3130          */
3131         family = sock->sk->sk_family;
3132         if (family == PF_INET || family == PF_INET6) {
3133                 char *addrp;
3134                 struct inode_security_struct *isec;
3135                 struct task_security_struct *tsec;
3136                 struct avc_audit_data ad;
3137                 struct sockaddr_in *addr4 = NULL;
3138                 struct sockaddr_in6 *addr6 = NULL;
3139                 unsigned short snum;
3140                 struct sock *sk = sock->sk;
3141                 u32 sid, node_perm, addrlen;
3142
3143                 tsec = current->security;
3144                 isec = SOCK_INODE(sock)->i_security;
3145
3146                 if (family == PF_INET) {
3147                         addr4 = (struct sockaddr_in *)address;
3148                         snum = ntohs(addr4->sin_port);
3149                         addrlen = sizeof(addr4->sin_addr.s_addr);
3150                         addrp = (char *)&addr4->sin_addr.s_addr;
3151                 } else {
3152                         addr6 = (struct sockaddr_in6 *)address;
3153                         snum = ntohs(addr6->sin6_port);
3154                         addrlen = sizeof(addr6->sin6_addr.s6_addr);
3155                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3156                 }
3157
3158                 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3159                            snum > ip_local_port_range_1)) {
3160                         err = security_port_sid(sk->sk_family, sk->sk_type,
3161                                                 sk->sk_protocol, snum, &sid);
3162                         if (err)
3163                                 goto out;
3164                         AVC_AUDIT_DATA_INIT(&ad,NET);
3165                         ad.u.net.sport = htons(snum);
3166                         ad.u.net.family = family;
3167                         err = avc_has_perm(isec->sid, sid,
3168                                            isec->sclass,
3169                                            SOCKET__NAME_BIND, &ad);
3170                         if (err)
3171                                 goto out;
3172                 }
3173                 
3174                 switch(isec->sclass) {
3175                 case SECCLASS_TCP_SOCKET:
3176                         node_perm = TCP_SOCKET__NODE_BIND;
3177                         break;
3178                         
3179                 case SECCLASS_UDP_SOCKET:
3180                         node_perm = UDP_SOCKET__NODE_BIND;
3181                         break;
3182                         
3183                 default:
3184                         node_perm = RAWIP_SOCKET__NODE_BIND;
3185                         break;
3186                 }
3187                 
3188                 err = security_node_sid(family, addrp, addrlen, &sid);
3189                 if (err)
3190                         goto out;
3191                 
3192                 AVC_AUDIT_DATA_INIT(&ad,NET);
3193                 ad.u.net.sport = htons(snum);
3194                 ad.u.net.family = family;
3195
3196                 if (family == PF_INET)
3197                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3198                 else
3199                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3200
3201                 err = avc_has_perm(isec->sid, sid,
3202                                    isec->sclass, node_perm, &ad);
3203                 if (err)
3204                         goto out;
3205         }
3206 out:
3207         return err;
3208 }
3209
3210 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3211 {
3212         struct inode_security_struct *isec;
3213         int err;
3214
3215         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3216         if (err)
3217                 return err;
3218
3219         /*
3220          * If a TCP socket, check name_connect permission for the port.
3221          */
3222         isec = SOCK_INODE(sock)->i_security;
3223         if (isec->sclass == SECCLASS_TCP_SOCKET) {
3224                 struct sock *sk = sock->sk;
3225                 struct avc_audit_data ad;
3226                 struct sockaddr_in *addr4 = NULL;
3227                 struct sockaddr_in6 *addr6 = NULL;
3228                 unsigned short snum;
3229                 u32 sid;
3230
3231                 if (sk->sk_family == PF_INET) {
3232                         addr4 = (struct sockaddr_in *)address;
3233                         if (addrlen < sizeof(struct sockaddr_in))
3234                                 return -EINVAL;
3235                         snum = ntohs(addr4->sin_port);
3236                 } else {
3237                         addr6 = (struct sockaddr_in6 *)address;
3238                         if (addrlen < SIN6_LEN_RFC2133)
3239                                 return -EINVAL;
3240                         snum = ntohs(addr6->sin6_port);
3241                 }
3242
3243                 err = security_port_sid(sk->sk_family, sk->sk_type,
3244                                         sk->sk_protocol, snum, &sid);
3245                 if (err)
3246                         goto out;
3247
3248                 AVC_AUDIT_DATA_INIT(&ad,NET);
3249                 ad.u.net.dport = htons(snum);
3250                 ad.u.net.family = sk->sk_family;
3251                 err = avc_has_perm(isec->sid, sid, isec->sclass,
3252                                    TCP_SOCKET__NAME_CONNECT, &ad);
3253                 if (err)
3254                         goto out;
3255         }
3256
3257 out:
3258         return err;
3259 }
3260
3261 static int selinux_socket_listen(struct socket *sock, int backlog)
3262 {
3263         return socket_has_perm(current, sock, SOCKET__LISTEN);
3264 }
3265
3266 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3267 {
3268         int err;
3269         struct inode_security_struct *isec;
3270         struct inode_security_struct *newisec;
3271
3272         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3273         if (err)
3274                 return err;
3275
3276         newisec = SOCK_INODE(newsock)->i_security;
3277
3278         isec = SOCK_INODE(sock)->i_security;
3279         newisec->sclass = isec->sclass;
3280         newisec->sid = isec->sid;
3281         newisec->initialized = 1;
3282