]> nv-tegra.nvidia Code Review - linux-3.10.git/blob - security/selinux/hooks.c
AUDIT: Round up audit skb expansion to AUDIT_BUFSIZ.
[linux-3.10.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  *
16  *      This program is free software; you can redistribute it and/or modify
17  *      it under the terms of the GNU General Public License version 2,
18  *      as published by the Free Software Foundation.
19  */
20
21 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/kernel.h>
25 #include <linux/ptrace.h>
26 #include <linux/errno.h>
27 #include <linux/sched.h>
28 #include <linux/security.h>
29 #include <linux/xattr.h>
30 #include <linux/capability.h>
31 #include <linux/unistd.h>
32 #include <linux/mm.h>
33 #include <linux/mman.h>
34 #include <linux/slab.h>
35 #include <linux/pagemap.h>
36 #include <linux/swap.h>
37 #include <linux/smp_lock.h>
38 #include <linux/spinlock.h>
39 #include <linux/syscalls.h>
40 #include <linux/file.h>
41 #include <linux/namei.h>
42 #include <linux/mount.h>
43 #include <linux/ext2_fs.h>
44 #include <linux/proc_fs.h>
45 #include <linux/kd.h>
46 #include <linux/netfilter_ipv4.h>
47 #include <linux/netfilter_ipv6.h>
48 #include <linux/tty.h>
49 #include <net/icmp.h>
50 #include <net/ip.h>             /* for sysctl_local_port_range[] */
51 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
52 #include <asm/uaccess.h>
53 #include <asm/semaphore.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
72 #include "avc.h"
73 #include "objsec.h"
74 #include "netif.h"
75
76 #define XATTR_SELINUX_SUFFIX "selinux"
77 #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
78
79 extern unsigned int policydb_loaded_version;
80 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
81
82 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
83 int selinux_enforcing = 0;
84
85 static int __init enforcing_setup(char *str)
86 {
87         selinux_enforcing = simple_strtol(str,NULL,0);
88         return 1;
89 }
90 __setup("enforcing=", enforcing_setup);
91 #endif
92
93 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
94 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
95
96 static int __init selinux_enabled_setup(char *str)
97 {
98         selinux_enabled = simple_strtol(str, NULL, 0);
99         return 1;
100 }
101 __setup("selinux=", selinux_enabled_setup);
102 #endif
103
104 /* Original (dummy) security module. */
105 static struct security_operations *original_ops = NULL;
106
107 /* Minimal support for a secondary security module,
108    just to allow the use of the dummy or capability modules.
109    The owlsm module can alternatively be used as a secondary
110    module as long as CONFIG_OWLSM_FD is not enabled. */
111 static struct security_operations *secondary_ops = NULL;
112
113 /* Lists of inode and superblock security structures initialized
114    before the policy was loaded. */
115 static LIST_HEAD(superblock_security_head);
116 static DEFINE_SPINLOCK(sb_security_lock);
117
118 /* Allocate and free functions for each kind of security blob. */
119
120 static int task_alloc_security(struct task_struct *task)
121 {
122         struct task_security_struct *tsec;
123
124         tsec = kmalloc(sizeof(struct task_security_struct), GFP_KERNEL);
125         if (!tsec)
126                 return -ENOMEM;
127
128         memset(tsec, 0, sizeof(struct task_security_struct));
129         tsec->magic = SELINUX_MAGIC;
130         tsec->task = task;
131         tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED;
132         task->security = tsec;
133
134         return 0;
135 }
136
137 static void task_free_security(struct task_struct *task)
138 {
139         struct task_security_struct *tsec = task->security;
140
141         if (!tsec || tsec->magic != SELINUX_MAGIC)
142                 return;
143
144         task->security = NULL;
145         kfree(tsec);
146 }
147
148 static int inode_alloc_security(struct inode *inode)
149 {
150         struct task_security_struct *tsec = current->security;
151         struct inode_security_struct *isec;
152
153         isec = kmalloc(sizeof(struct inode_security_struct), GFP_KERNEL);
154         if (!isec)
155                 return -ENOMEM;
156
157         memset(isec, 0, sizeof(struct inode_security_struct));
158         init_MUTEX(&isec->sem);
159         INIT_LIST_HEAD(&isec->list);
160         isec->magic = SELINUX_MAGIC;
161         isec->inode = inode;
162         isec->sid = SECINITSID_UNLABELED;
163         isec->sclass = SECCLASS_FILE;
164         if (tsec && tsec->magic == SELINUX_MAGIC)
165                 isec->task_sid = tsec->sid;
166         else
167                 isec->task_sid = SECINITSID_UNLABELED;
168         inode->i_security = isec;
169
170         return 0;
171 }
172
173 static void inode_free_security(struct inode *inode)
174 {
175         struct inode_security_struct *isec = inode->i_security;
176         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
177
178         if (!isec || isec->magic != SELINUX_MAGIC)
179                 return;
180
181         spin_lock(&sbsec->isec_lock);
182         if (!list_empty(&isec->list))
183                 list_del_init(&isec->list);
184         spin_unlock(&sbsec->isec_lock);
185
186         inode->i_security = NULL;
187         kfree(isec);
188 }
189
190 static int file_alloc_security(struct file *file)
191 {
192         struct task_security_struct *tsec = current->security;
193         struct file_security_struct *fsec;
194
195         fsec = kmalloc(sizeof(struct file_security_struct), GFP_ATOMIC);
196         if (!fsec)
197                 return -ENOMEM;
198
199         memset(fsec, 0, sizeof(struct file_security_struct));
200         fsec->magic = SELINUX_MAGIC;
201         fsec->file = file;
202         if (tsec && tsec->magic == SELINUX_MAGIC) {
203                 fsec->sid = tsec->sid;
204                 fsec->fown_sid = tsec->sid;
205         } else {
206                 fsec->sid = SECINITSID_UNLABELED;
207                 fsec->fown_sid = SECINITSID_UNLABELED;
208         }
209         file->f_security = fsec;
210
211         return 0;
212 }
213
214 static void file_free_security(struct file *file)
215 {
216         struct file_security_struct *fsec = file->f_security;
217
218         if (!fsec || fsec->magic != SELINUX_MAGIC)
219                 return;
220
221         file->f_security = NULL;
222         kfree(fsec);
223 }
224
225 static int superblock_alloc_security(struct super_block *sb)
226 {
227         struct superblock_security_struct *sbsec;
228
229         sbsec = kmalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
230         if (!sbsec)
231                 return -ENOMEM;
232
233         memset(sbsec, 0, sizeof(struct superblock_security_struct));
234         init_MUTEX(&sbsec->sem);
235         INIT_LIST_HEAD(&sbsec->list);
236         INIT_LIST_HEAD(&sbsec->isec_head);
237         spin_lock_init(&sbsec->isec_lock);
238         sbsec->magic = SELINUX_MAGIC;
239         sbsec->sb = sb;
240         sbsec->sid = SECINITSID_UNLABELED;
241         sbsec->def_sid = SECINITSID_FILE;
242         sb->s_security = sbsec;
243
244         return 0;
245 }
246
247 static void superblock_free_security(struct super_block *sb)
248 {
249         struct superblock_security_struct *sbsec = sb->s_security;
250
251         if (!sbsec || sbsec->magic != SELINUX_MAGIC)
252                 return;
253
254         spin_lock(&sb_security_lock);
255         if (!list_empty(&sbsec->list))
256                 list_del_init(&sbsec->list);
257         spin_unlock(&sb_security_lock);
258
259         sb->s_security = NULL;
260         kfree(sbsec);
261 }
262
263 #ifdef CONFIG_SECURITY_NETWORK
264 static int sk_alloc_security(struct sock *sk, int family, int priority)
265 {
266         struct sk_security_struct *ssec;
267
268         if (family != PF_UNIX)
269                 return 0;
270
271         ssec = kmalloc(sizeof(*ssec), priority);
272         if (!ssec)
273                 return -ENOMEM;
274
275         memset(ssec, 0, sizeof(*ssec));
276         ssec->magic = SELINUX_MAGIC;
277         ssec->sk = sk;
278         ssec->peer_sid = SECINITSID_UNLABELED;
279         sk->sk_security = ssec;
280
281         return 0;
282 }
283
284 static void sk_free_security(struct sock *sk)
285 {
286         struct sk_security_struct *ssec = sk->sk_security;
287
288         if (sk->sk_family != PF_UNIX || ssec->magic != SELINUX_MAGIC)
289                 return;
290
291         sk->sk_security = NULL;
292         kfree(ssec);
293 }
294 #endif  /* CONFIG_SECURITY_NETWORK */
295
296 /* The security server must be initialized before
297    any labeling or access decisions can be provided. */
298 extern int ss_initialized;
299
300 /* The file system's label must be initialized prior to use. */
301
302 static char *labeling_behaviors[6] = {
303         "uses xattr",
304         "uses transition SIDs",
305         "uses task SIDs",
306         "uses genfs_contexts",
307         "not configured for labeling",
308         "uses mountpoint labeling",
309 };
310
311 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
312
313 static inline int inode_doinit(struct inode *inode)
314 {
315         return inode_doinit_with_dentry(inode, NULL);
316 }
317
318 enum {
319         Opt_context = 1,
320         Opt_fscontext = 2,
321         Opt_defcontext = 4,
322 };
323
324 static match_table_t tokens = {
325         {Opt_context, "context=%s"},
326         {Opt_fscontext, "fscontext=%s"},
327         {Opt_defcontext, "defcontext=%s"},
328 };
329
330 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
331
332 static int try_context_mount(struct super_block *sb, void *data)
333 {
334         char *context = NULL, *defcontext = NULL;
335         const char *name;
336         u32 sid;
337         int alloc = 0, rc = 0, seen = 0;
338         struct task_security_struct *tsec = current->security;
339         struct superblock_security_struct *sbsec = sb->s_security;
340
341         if (!data)
342                 goto out;
343
344         name = sb->s_type->name;
345
346         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
347
348                 /* NFS we understand. */
349                 if (!strcmp(name, "nfs")) {
350                         struct nfs_mount_data *d = data;
351
352                         if (d->version <  NFS_MOUNT_VERSION)
353                                 goto out;
354
355                         if (d->context[0]) {
356                                 context = d->context;
357                                 seen |= Opt_context;
358                         }
359                 } else
360                         goto out;
361
362         } else {
363                 /* Standard string-based options. */
364                 char *p, *options = data;
365
366                 while ((p = strsep(&options, ",")) != NULL) {
367                         int token;
368                         substring_t args[MAX_OPT_ARGS];
369
370                         if (!*p)
371                                 continue;
372
373                         token = match_token(p, tokens, args);
374
375                         switch (token) {
376                         case Opt_context:
377                                 if (seen) {
378                                         rc = -EINVAL;
379                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
380                                         goto out_free;
381                                 }
382                                 context = match_strdup(&args[0]);
383                                 if (!context) {
384                                         rc = -ENOMEM;
385                                         goto out_free;
386                                 }
387                                 if (!alloc)
388                                         alloc = 1;
389                                 seen |= Opt_context;
390                                 break;
391
392                         case Opt_fscontext:
393                                 if (seen & (Opt_context|Opt_fscontext)) {
394                                         rc = -EINVAL;
395                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
396                                         goto out_free;
397                                 }
398                                 context = match_strdup(&args[0]);
399                                 if (!context) {
400                                         rc = -ENOMEM;
401                                         goto out_free;
402                                 }
403                                 if (!alloc)
404                                         alloc = 1;
405                                 seen |= Opt_fscontext;
406                                 break;
407
408                         case Opt_defcontext:
409                                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
410                                         rc = -EINVAL;
411                                         printk(KERN_WARNING "SELinux:  "
412                                                "defcontext option is invalid "
413                                                "for this filesystem type\n");
414                                         goto out_free;
415                                 }
416                                 if (seen & (Opt_context|Opt_defcontext)) {
417                                         rc = -EINVAL;
418                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
419                                         goto out_free;
420                                 }
421                                 defcontext = match_strdup(&args[0]);
422                                 if (!defcontext) {
423                                         rc = -ENOMEM;
424                                         goto out_free;
425                                 }
426                                 if (!alloc)
427                                         alloc = 1;
428                                 seen |= Opt_defcontext;
429                                 break;
430
431                         default:
432                                 rc = -EINVAL;
433                                 printk(KERN_WARNING "SELinux:  unknown mount "
434                                        "option\n");
435                                 goto out_free;
436
437                         }
438                 }
439         }
440
441         if (!seen)
442                 goto out;
443
444         if (context) {
445                 rc = security_context_to_sid(context, strlen(context), &sid);
446                 if (rc) {
447                         printk(KERN_WARNING "SELinux: security_context_to_sid"
448                                "(%s) failed for (dev %s, type %s) errno=%d\n",
449                                context, sb->s_id, name, rc);
450                         goto out_free;
451                 }
452
453                 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
454                                   FILESYSTEM__RELABELFROM, NULL);
455                 if (rc)
456                         goto out_free;
457
458                 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
459                                   FILESYSTEM__RELABELTO, NULL);
460                 if (rc)
461                         goto out_free;
462
463                 sbsec->sid = sid;
464
465                 if (seen & Opt_context)
466                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
467         }
468
469         if (defcontext) {
470                 rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
471                 if (rc) {
472                         printk(KERN_WARNING "SELinux: security_context_to_sid"
473                                "(%s) failed for (dev %s, type %s) errno=%d\n",
474                                defcontext, sb->s_id, name, rc);
475                         goto out_free;
476                 }
477
478                 if (sid == sbsec->def_sid)
479                         goto out_free;
480
481                 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
482                                   FILESYSTEM__RELABELFROM, NULL);
483                 if (rc)
484                         goto out_free;
485
486                 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
487                                   FILESYSTEM__ASSOCIATE, NULL);
488                 if (rc)
489                         goto out_free;
490
491                 sbsec->def_sid = sid;
492         }
493
494 out_free:
495         if (alloc) {
496                 kfree(context);
497                 kfree(defcontext);
498         }
499 out:
500         return rc;
501 }
502
503 static int superblock_doinit(struct super_block *sb, void *data)
504 {
505         struct superblock_security_struct *sbsec = sb->s_security;
506         struct dentry *root = sb->s_root;
507         struct inode *inode = root->d_inode;
508         int rc = 0;
509
510         down(&sbsec->sem);
511         if (sbsec->initialized)
512                 goto out;
513
514         if (!ss_initialized) {
515                 /* Defer initialization until selinux_complete_init,
516                    after the initial policy is loaded and the security
517                    server is ready to handle calls. */
518                 spin_lock(&sb_security_lock);
519                 if (list_empty(&sbsec->list))
520                         list_add(&sbsec->list, &superblock_security_head);
521                 spin_unlock(&sb_security_lock);
522                 goto out;
523         }
524
525         /* Determine the labeling behavior to use for this filesystem type. */
526         rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
527         if (rc) {
528                 printk(KERN_WARNING "%s:  security_fs_use(%s) returned %d\n",
529                        __FUNCTION__, sb->s_type->name, rc);
530                 goto out;
531         }
532
533         rc = try_context_mount(sb, data);
534         if (rc)
535                 goto out;
536
537         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
538                 /* Make sure that the xattr handler exists and that no
539                    error other than -ENODATA is returned by getxattr on
540                    the root directory.  -ENODATA is ok, as this may be
541                    the first boot of the SELinux kernel before we have
542                    assigned xattr values to the filesystem. */
543                 if (!inode->i_op->getxattr) {
544                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
545                                "xattr support\n", sb->s_id, sb->s_type->name);
546                         rc = -EOPNOTSUPP;
547                         goto out;
548                 }
549                 rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
550                 if (rc < 0 && rc != -ENODATA) {
551                         if (rc == -EOPNOTSUPP)
552                                 printk(KERN_WARNING "SELinux: (dev %s, type "
553                                        "%s) has no security xattr handler\n",
554                                        sb->s_id, sb->s_type->name);
555                         else
556                                 printk(KERN_WARNING "SELinux: (dev %s, type "
557                                        "%s) getxattr errno %d\n", sb->s_id,
558                                        sb->s_type->name, -rc);
559                         goto out;
560                 }
561         }
562
563         if (strcmp(sb->s_type->name, "proc") == 0)
564                 sbsec->proc = 1;
565
566         sbsec->initialized = 1;
567
568         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
569                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), unknown behavior\n",
570                        sb->s_id, sb->s_type->name);
571         }
572         else {
573                 printk(KERN_INFO "SELinux: initialized (dev %s, type %s), %s\n",
574                        sb->s_id, sb->s_type->name,
575                        labeling_behaviors[sbsec->behavior-1]);
576         }
577
578         /* Initialize the root inode. */
579         rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
580
581         /* Initialize any other inodes associated with the superblock, e.g.
582            inodes created prior to initial policy load or inodes created
583            during get_sb by a pseudo filesystem that directly
584            populates itself. */
585         spin_lock(&sbsec->isec_lock);
586 next_inode:
587         if (!list_empty(&sbsec->isec_head)) {
588                 struct inode_security_struct *isec =
589                                 list_entry(sbsec->isec_head.next,
590                                            struct inode_security_struct, list);
591                 struct inode *inode = isec->inode;
592                 spin_unlock(&sbsec->isec_lock);
593                 inode = igrab(inode);
594                 if (inode) {
595                         if (!IS_PRIVATE (inode))
596                                 inode_doinit(inode);
597                         iput(inode);
598                 }
599                 spin_lock(&sbsec->isec_lock);
600                 list_del_init(&isec->list);
601                 goto next_inode;
602         }
603         spin_unlock(&sbsec->isec_lock);
604 out:
605         up(&sbsec->sem);
606         return rc;
607 }
608
609 static inline u16 inode_mode_to_security_class(umode_t mode)
610 {
611         switch (mode & S_IFMT) {
612         case S_IFSOCK:
613                 return SECCLASS_SOCK_FILE;
614         case S_IFLNK:
615                 return SECCLASS_LNK_FILE;
616         case S_IFREG:
617                 return SECCLASS_FILE;
618         case S_IFBLK:
619                 return SECCLASS_BLK_FILE;
620         case S_IFDIR:
621                 return SECCLASS_DIR;
622         case S_IFCHR:
623                 return SECCLASS_CHR_FILE;
624         case S_IFIFO:
625                 return SECCLASS_FIFO_FILE;
626
627         }
628
629         return SECCLASS_FILE;
630 }
631
632 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
633 {
634         switch (family) {
635         case PF_UNIX:
636                 switch (type) {
637                 case SOCK_STREAM:
638                 case SOCK_SEQPACKET:
639                         return SECCLASS_UNIX_STREAM_SOCKET;
640                 case SOCK_DGRAM:
641                         return SECCLASS_UNIX_DGRAM_SOCKET;
642                 }
643                 break;
644         case PF_INET:
645         case PF_INET6:
646                 switch (type) {
647                 case SOCK_STREAM:
648                         return SECCLASS_TCP_SOCKET;
649                 case SOCK_DGRAM:
650                         return SECCLASS_UDP_SOCKET;
651                 case SOCK_RAW:
652                         return SECCLASS_RAWIP_SOCKET;
653                 }
654                 break;
655         case PF_NETLINK:
656                 switch (protocol) {
657                 case NETLINK_ROUTE:
658                         return SECCLASS_NETLINK_ROUTE_SOCKET;
659                 case NETLINK_FIREWALL:
660                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
661                 case NETLINK_TCPDIAG:
662                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
663                 case NETLINK_NFLOG:
664                         return SECCLASS_NETLINK_NFLOG_SOCKET;
665                 case NETLINK_XFRM:
666                         return SECCLASS_NETLINK_XFRM_SOCKET;
667                 case NETLINK_SELINUX:
668                         return SECCLASS_NETLINK_SELINUX_SOCKET;
669                 case NETLINK_AUDIT:
670                         return SECCLASS_NETLINK_AUDIT_SOCKET;
671                 case NETLINK_IP6_FW:
672                         return SECCLASS_NETLINK_IP6FW_SOCKET;
673                 case NETLINK_DNRTMSG:
674                         return SECCLASS_NETLINK_DNRT_SOCKET;
675                 case NETLINK_KOBJECT_UEVENT:
676                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
677                 default:
678                         return SECCLASS_NETLINK_SOCKET;
679                 }
680         case PF_PACKET:
681                 return SECCLASS_PACKET_SOCKET;
682         case PF_KEY:
683                 return SECCLASS_KEY_SOCKET;
684         }
685
686         return SECCLASS_SOCKET;
687 }
688
689 #ifdef CONFIG_PROC_FS
690 static int selinux_proc_get_sid(struct proc_dir_entry *de,
691                                 u16 tclass,
692                                 u32 *sid)
693 {
694         int buflen, rc;
695         char *buffer, *path, *end;
696
697         buffer = (char*)__get_free_page(GFP_KERNEL);
698         if (!buffer)
699                 return -ENOMEM;
700
701         buflen = PAGE_SIZE;
702         end = buffer+buflen;
703         *--end = '\0';
704         buflen--;
705         path = end-1;
706         *path = '/';
707         while (de && de != de->parent) {
708                 buflen -= de->namelen + 1;
709                 if (buflen < 0)
710                         break;
711                 end -= de->namelen;
712                 memcpy(end, de->name, de->namelen);
713                 *--end = '/';
714                 path = end;
715                 de = de->parent;
716         }
717         rc = security_genfs_sid("proc", path, tclass, sid);
718         free_page((unsigned long)buffer);
719         return rc;
720 }
721 #else
722 static int selinux_proc_get_sid(struct proc_dir_entry *de,
723                                 u16 tclass,
724                                 u32 *sid)
725 {
726         return -EINVAL;
727 }
728 #endif
729
730 /* The inode's security attributes must be initialized before first use. */
731 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
732 {
733         struct superblock_security_struct *sbsec = NULL;
734         struct inode_security_struct *isec = inode->i_security;
735         u32 sid;
736         struct dentry *dentry;
737 #define INITCONTEXTLEN 255
738         char *context = NULL;
739         unsigned len = 0;
740         int rc = 0;
741         int hold_sem = 0;
742
743         if (isec->initialized)
744                 goto out;
745
746         down(&isec->sem);
747         hold_sem = 1;
748         if (isec->initialized)
749                 goto out;
750
751         sbsec = inode->i_sb->s_security;
752         if (!sbsec->initialized) {
753                 /* Defer initialization until selinux_complete_init,
754                    after the initial policy is loaded and the security
755                    server is ready to handle calls. */
756                 spin_lock(&sbsec->isec_lock);
757                 if (list_empty(&isec->list))
758                         list_add(&isec->list, &sbsec->isec_head);
759                 spin_unlock(&sbsec->isec_lock);
760                 goto out;
761         }
762
763         switch (sbsec->behavior) {
764         case SECURITY_FS_USE_XATTR:
765                 if (!inode->i_op->getxattr) {
766                         isec->sid = sbsec->def_sid;
767                         break;
768                 }
769
770                 /* Need a dentry, since the xattr API requires one.
771                    Life would be simpler if we could just pass the inode. */
772                 if (opt_dentry) {
773                         /* Called from d_instantiate or d_splice_alias. */
774                         dentry = dget(opt_dentry);
775                 } else {
776                         /* Called from selinux_complete_init, try to find a dentry. */
777                         dentry = d_find_alias(inode);
778                 }
779                 if (!dentry) {
780                         printk(KERN_WARNING "%s:  no dentry for dev=%s "
781                                "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id,
782                                inode->i_ino);
783                         goto out;
784                 }
785
786                 len = INITCONTEXTLEN;
787                 context = kmalloc(len, GFP_KERNEL);
788                 if (!context) {
789                         rc = -ENOMEM;
790                         dput(dentry);
791                         goto out;
792                 }
793                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
794                                            context, len);
795                 if (rc == -ERANGE) {
796                         /* Need a larger buffer.  Query for the right size. */
797                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
798                                                    NULL, 0);
799                         if (rc < 0) {
800                                 dput(dentry);
801                                 goto out;
802                         }
803                         kfree(context);
804                         len = rc;
805                         context = kmalloc(len, GFP_KERNEL);
806                         if (!context) {
807                                 rc = -ENOMEM;
808                                 dput(dentry);
809                                 goto out;
810                         }
811                         rc = inode->i_op->getxattr(dentry,
812                                                    XATTR_NAME_SELINUX,
813                                                    context, len);
814                 }
815                 dput(dentry);
816                 if (rc < 0) {
817                         if (rc != -ENODATA) {
818                                 printk(KERN_WARNING "%s:  getxattr returned "
819                                        "%d for dev=%s ino=%ld\n", __FUNCTION__,
820                                        -rc, inode->i_sb->s_id, inode->i_ino);
821                                 kfree(context);
822                                 goto out;
823                         }
824                         /* Map ENODATA to the default file SID */
825                         sid = sbsec->def_sid;
826                         rc = 0;
827                 } else {
828                         rc = security_context_to_sid(context, rc, &sid);
829                         if (rc) {
830                                 printk(KERN_WARNING "%s:  context_to_sid(%s) "
831                                        "returned %d for dev=%s ino=%ld\n",
832                                        __FUNCTION__, context, -rc,
833                                        inode->i_sb->s_id, inode->i_ino);
834                                 kfree(context);
835                                 /* Leave with the unlabeled SID */
836                                 rc = 0;
837                                 break;
838                         }
839                 }
840                 kfree(context);
841                 isec->sid = sid;
842                 break;
843         case SECURITY_FS_USE_TASK:
844                 isec->sid = isec->task_sid;
845                 break;
846         case SECURITY_FS_USE_TRANS:
847                 /* Default to the fs SID. */
848                 isec->sid = sbsec->sid;
849
850                 /* Try to obtain a transition SID. */
851                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
852                 rc = security_transition_sid(isec->task_sid,
853                                              sbsec->sid,
854                                              isec->sclass,
855                                              &sid);
856                 if (rc)
857                         goto out;
858                 isec->sid = sid;
859                 break;
860         default:
861                 /* Default to the fs SID. */
862                 isec->sid = sbsec->sid;
863
864                 if (sbsec->proc) {
865                         struct proc_inode *proci = PROC_I(inode);
866                         if (proci->pde) {
867                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
868                                 rc = selinux_proc_get_sid(proci->pde,
869                                                           isec->sclass,
870                                                           &sid);
871                                 if (rc)
872                                         goto out;
873                                 isec->sid = sid;
874                         }
875                 }
876                 break;
877         }
878
879         isec->initialized = 1;
880
881 out:
882         if (isec->sclass == SECCLASS_FILE)
883                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
884
885         if (hold_sem)
886                 up(&isec->sem);
887         return rc;
888 }
889
890 /* Convert a Linux signal to an access vector. */
891 static inline u32 signal_to_av(int sig)
892 {
893         u32 perm = 0;
894
895         switch (sig) {
896         case SIGCHLD:
897                 /* Commonly granted from child to parent. */
898                 perm = PROCESS__SIGCHLD;
899                 break;
900         case SIGKILL:
901                 /* Cannot be caught or ignored */
902                 perm = PROCESS__SIGKILL;
903                 break;
904         case SIGSTOP:
905                 /* Cannot be caught or ignored */
906                 perm = PROCESS__SIGSTOP;
907                 break;
908         default:
909                 /* All other signals. */
910                 perm = PROCESS__SIGNAL;
911                 break;
912         }
913
914         return perm;
915 }
916
917 /* Check permission betweeen a pair of tasks, e.g. signal checks,
918    fork check, ptrace check, etc. */
919 static int task_has_perm(struct task_struct *tsk1,
920                          struct task_struct *tsk2,
921                          u32 perms)
922 {
923         struct task_security_struct *tsec1, *tsec2;
924
925         tsec1 = tsk1->security;
926         tsec2 = tsk2->security;
927         return avc_has_perm(tsec1->sid, tsec2->sid,
928                             SECCLASS_PROCESS, perms, NULL);
929 }
930
931 /* Check whether a task is allowed to use a capability. */
932 static int task_has_capability(struct task_struct *tsk,
933                                int cap)
934 {
935         struct task_security_struct *tsec;
936         struct avc_audit_data ad;
937
938         tsec = tsk->security;
939
940         AVC_AUDIT_DATA_INIT(&ad,CAP);
941         ad.tsk = tsk;
942         ad.u.cap = cap;
943
944         return avc_has_perm(tsec->sid, tsec->sid,
945                             SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
946 }
947
948 /* Check whether a task is allowed to use a system operation. */
949 static int task_has_system(struct task_struct *tsk,
950                            u32 perms)
951 {
952         struct task_security_struct *tsec;
953
954         tsec = tsk->security;
955
956         return avc_has_perm(tsec->sid, SECINITSID_KERNEL,
957                             SECCLASS_SYSTEM, perms, NULL);
958 }
959
960 /* Check whether a task has a particular permission to an inode.
961    The 'adp' parameter is optional and allows other audit
962    data to be passed (e.g. the dentry). */
963 static int inode_has_perm(struct task_struct *tsk,
964                           struct inode *inode,
965                           u32 perms,
966                           struct avc_audit_data *adp)
967 {
968         struct task_security_struct *tsec;
969         struct inode_security_struct *isec;
970         struct avc_audit_data ad;
971
972         tsec = tsk->security;
973         isec = inode->i_security;
974
975         if (!adp) {
976                 adp = &ad;
977                 AVC_AUDIT_DATA_INIT(&ad, FS);
978                 ad.u.fs.inode = inode;
979         }
980
981         return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp);
982 }
983
984 /* Same as inode_has_perm, but pass explicit audit data containing
985    the dentry to help the auditing code to more easily generate the
986    pathname if needed. */
987 static inline int dentry_has_perm(struct task_struct *tsk,
988                                   struct vfsmount *mnt,
989                                   struct dentry *dentry,
990                                   u32 av)
991 {
992         struct inode *inode = dentry->d_inode;
993         struct avc_audit_data ad;
994         AVC_AUDIT_DATA_INIT(&ad,FS);
995         ad.u.fs.mnt = mnt;
996         ad.u.fs.dentry = dentry;
997         return inode_has_perm(tsk, inode, av, &ad);
998 }
999
1000 /* Check whether a task can use an open file descriptor to
1001    access an inode in a given way.  Check access to the
1002    descriptor itself, and then use dentry_has_perm to
1003    check a particular permission to the file.
1004    Access to the descriptor is implicitly granted if it
1005    has the same SID as the process.  If av is zero, then
1006    access to the file is not checked, e.g. for cases
1007    where only the descriptor is affected like seek. */
1008 static inline int file_has_perm(struct task_struct *tsk,
1009                                 struct file *file,
1010                                 u32 av)
1011 {
1012         struct task_security_struct *tsec = tsk->security;
1013         struct file_security_struct *fsec = file->f_security;
1014         struct vfsmount *mnt = file->f_vfsmnt;
1015         struct dentry *dentry = file->f_dentry;
1016         struct inode *inode = dentry->d_inode;
1017         struct avc_audit_data ad;
1018         int rc;
1019
1020         AVC_AUDIT_DATA_INIT(&ad, FS);
1021         ad.u.fs.mnt = mnt;
1022         ad.u.fs.dentry = dentry;
1023
1024         if (tsec->sid != fsec->sid) {
1025                 rc = avc_has_perm(tsec->sid, fsec->sid,
1026                                   SECCLASS_FD,
1027                                   FD__USE,
1028                                   &ad);
1029                 if (rc)
1030                         return rc;
1031         }
1032
1033         /* av is zero if only checking access to the descriptor. */
1034         if (av)
1035                 return inode_has_perm(tsk, inode, av, &ad);
1036
1037         return 0;
1038 }
1039
1040 /* Check whether a task can create a file. */
1041 static int may_create(struct inode *dir,
1042                       struct dentry *dentry,
1043                       u16 tclass)
1044 {
1045         struct task_security_struct *tsec;
1046         struct inode_security_struct *dsec;
1047         struct superblock_security_struct *sbsec;
1048         u32 newsid;
1049         struct avc_audit_data ad;
1050         int rc;
1051
1052         tsec = current->security;
1053         dsec = dir->i_security;
1054         sbsec = dir->i_sb->s_security;
1055
1056         AVC_AUDIT_DATA_INIT(&ad, FS);
1057         ad.u.fs.dentry = dentry;
1058
1059         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
1060                           DIR__ADD_NAME | DIR__SEARCH,
1061                           &ad);
1062         if (rc)
1063                 return rc;
1064
1065         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1066                 newsid = tsec->create_sid;
1067         } else {
1068                 rc = security_transition_sid(tsec->sid, dsec->sid, tclass,
1069                                              &newsid);
1070                 if (rc)
1071                         return rc;
1072         }
1073
1074         rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad);
1075         if (rc)
1076                 return rc;
1077
1078         return avc_has_perm(newsid, sbsec->sid,
1079                             SECCLASS_FILESYSTEM,
1080                             FILESYSTEM__ASSOCIATE, &ad);
1081 }
1082
1083 #define MAY_LINK   0
1084 #define MAY_UNLINK 1
1085 #define MAY_RMDIR  2
1086
1087 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1088 static int may_link(struct inode *dir,
1089                     struct dentry *dentry,
1090                     int kind)
1091
1092 {
1093         struct task_security_struct *tsec;
1094         struct inode_security_struct *dsec, *isec;
1095         struct avc_audit_data ad;
1096         u32 av;
1097         int rc;
1098
1099         tsec = current->security;
1100         dsec = dir->i_security;
1101         isec = dentry->d_inode->i_security;
1102
1103         AVC_AUDIT_DATA_INIT(&ad, FS);
1104         ad.u.fs.dentry = dentry;
1105
1106         av = DIR__SEARCH;
1107         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1108         rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad);
1109         if (rc)
1110                 return rc;
1111
1112         switch (kind) {
1113         case MAY_LINK:
1114                 av = FILE__LINK;
1115                 break;
1116         case MAY_UNLINK:
1117                 av = FILE__UNLINK;
1118                 break;
1119         case MAY_RMDIR:
1120                 av = DIR__RMDIR;
1121                 break;
1122         default:
1123                 printk(KERN_WARNING "may_link:  unrecognized kind %d\n", kind);
1124                 return 0;
1125         }
1126
1127         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad);
1128         return rc;
1129 }
1130
1131 static inline int may_rename(struct inode *old_dir,
1132                              struct dentry *old_dentry,
1133                              struct inode *new_dir,
1134                              struct dentry *new_dentry)
1135 {
1136         struct task_security_struct *tsec;
1137         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1138         struct avc_audit_data ad;
1139         u32 av;
1140         int old_is_dir, new_is_dir;
1141         int rc;
1142
1143         tsec = current->security;
1144         old_dsec = old_dir->i_security;
1145         old_isec = old_dentry->d_inode->i_security;
1146         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1147         new_dsec = new_dir->i_security;
1148
1149         AVC_AUDIT_DATA_INIT(&ad, FS);
1150
1151         ad.u.fs.dentry = old_dentry;
1152         rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
1153                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1154         if (rc)
1155                 return rc;
1156         rc = avc_has_perm(tsec->sid, old_isec->sid,
1157                           old_isec->sclass, FILE__RENAME, &ad);
1158         if (rc)
1159                 return rc;
1160         if (old_is_dir && new_dir != old_dir) {
1161                 rc = avc_has_perm(tsec->sid, old_isec->sid,
1162                                   old_isec->sclass, DIR__REPARENT, &ad);
1163                 if (rc)
1164                         return rc;
1165         }
1166
1167         ad.u.fs.dentry = new_dentry;
1168         av = DIR__ADD_NAME | DIR__SEARCH;
1169         if (new_dentry->d_inode)
1170                 av |= DIR__REMOVE_NAME;
1171         rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1172         if (rc)
1173                 return rc;
1174         if (new_dentry->d_inode) {
1175                 new_isec = new_dentry->d_inode->i_security;
1176                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1177                 rc = avc_has_perm(tsec->sid, new_isec->sid,
1178                                   new_isec->sclass,
1179                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1180                 if (rc)
1181                         return rc;
1182         }
1183
1184         return 0;
1185 }
1186
1187 /* Check whether a task can perform a filesystem operation. */
1188 static int superblock_has_perm(struct task_struct *tsk,
1189                                struct super_block *sb,
1190                                u32 perms,
1191                                struct avc_audit_data *ad)
1192 {
1193         struct task_security_struct *tsec;
1194         struct superblock_security_struct *sbsec;
1195
1196         tsec = tsk->security;
1197         sbsec = sb->s_security;
1198         return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
1199                             perms, ad);
1200 }
1201
1202 /* Convert a Linux mode and permission mask to an access vector. */
1203 static inline u32 file_mask_to_av(int mode, int mask)
1204 {
1205         u32 av = 0;
1206
1207         if ((mode & S_IFMT) != S_IFDIR) {
1208                 if (mask & MAY_EXEC)
1209                         av |= FILE__EXECUTE;
1210                 if (mask & MAY_READ)
1211                         av |= FILE__READ;
1212
1213                 if (mask & MAY_APPEND)
1214                         av |= FILE__APPEND;
1215                 else if (mask & MAY_WRITE)
1216                         av |= FILE__WRITE;
1217
1218         } else {
1219                 if (mask & MAY_EXEC)
1220                         av |= DIR__SEARCH;
1221                 if (mask & MAY_WRITE)
1222                         av |= DIR__WRITE;
1223                 if (mask & MAY_READ)
1224                         av |= DIR__READ;
1225         }
1226
1227         return av;
1228 }
1229
1230 /* Convert a Linux file to an access vector. */
1231 static inline u32 file_to_av(struct file *file)
1232 {
1233         u32 av = 0;
1234
1235         if (file->f_mode & FMODE_READ)
1236                 av |= FILE__READ;
1237         if (file->f_mode & FMODE_WRITE) {
1238                 if (file->f_flags & O_APPEND)
1239                         av |= FILE__APPEND;
1240                 else
1241                         av |= FILE__WRITE;
1242         }
1243
1244         return av;
1245 }
1246
1247 /* Set an inode's SID to a specified value. */
1248 static int inode_security_set_sid(struct inode *inode, u32 sid)
1249 {
1250         struct inode_security_struct *isec = inode->i_security;
1251         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
1252
1253         if (!sbsec->initialized) {
1254                 /* Defer initialization to selinux_complete_init. */
1255                 return 0;
1256         }
1257
1258         down(&isec->sem);
1259         isec->sclass = inode_mode_to_security_class(inode->i_mode);
1260         isec->sid = sid;
1261         isec->initialized = 1;
1262         up(&isec->sem);
1263         return 0;
1264 }
1265
1266 /* Set the security attributes on a newly created file. */
1267 static int post_create(struct inode *dir,
1268                        struct dentry *dentry)
1269 {
1270
1271         struct task_security_struct *tsec;
1272         struct inode *inode;
1273         struct inode_security_struct *dsec;
1274         struct superblock_security_struct *sbsec;
1275         u32 newsid;
1276         char *context;
1277         unsigned int len;
1278         int rc;
1279
1280         tsec = current->security;
1281         dsec = dir->i_security;
1282         sbsec = dir->i_sb->s_security;
1283
1284         inode = dentry->d_inode;
1285         if (!inode) {
1286                 /* Some file system types (e.g. NFS) may not instantiate
1287                    a dentry for all create operations (e.g. symlink),
1288                    so we have to check to see if the inode is non-NULL. */
1289                 printk(KERN_WARNING "post_create:  no inode, dir (dev=%s, "
1290                        "ino=%ld)\n", dir->i_sb->s_id, dir->i_ino);
1291                 return 0;
1292         }
1293
1294         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
1295                 newsid = tsec->create_sid;
1296         } else {
1297                 rc = security_transition_sid(tsec->sid, dsec->sid,
1298                                              inode_mode_to_security_class(inode->i_mode),
1299                                              &newsid);
1300                 if (rc) {
1301                         printk(KERN_WARNING "post_create:  "
1302                                "security_transition_sid failed, rc=%d (dev=%s "
1303                                "ino=%ld)\n",
1304                                -rc, inode->i_sb->s_id, inode->i_ino);
1305                         return rc;
1306                 }
1307         }
1308
1309         rc = inode_security_set_sid(inode, newsid);
1310         if (rc) {
1311                 printk(KERN_WARNING "post_create:  inode_security_set_sid "
1312                        "failed, rc=%d (dev=%s ino=%ld)\n",
1313                        -rc, inode->i_sb->s_id, inode->i_ino);
1314                 return rc;
1315         }
1316
1317         if (sbsec->behavior == SECURITY_FS_USE_XATTR &&
1318             inode->i_op->setxattr) {
1319                 /* Use extended attributes. */
1320                 rc = security_sid_to_context(newsid, &context, &len);
1321                 if (rc) {
1322                         printk(KERN_WARNING "post_create:  sid_to_context "
1323                                "failed, rc=%d (dev=%s ino=%ld)\n",
1324                                -rc, inode->i_sb->s_id, inode->i_ino);
1325                         return rc;
1326                 }
1327                 down(&inode->i_sem);
1328                 rc = inode->i_op->setxattr(dentry,
1329                                            XATTR_NAME_SELINUX,
1330                                            context, len, 0);
1331                 up(&inode->i_sem);
1332                 kfree(context);
1333                 if (rc < 0) {
1334                         printk(KERN_WARNING "post_create:  setxattr failed, "
1335                                "rc=%d (dev=%s ino=%ld)\n",
1336                                -rc, inode->i_sb->s_id, inode->i_ino);
1337                         return rc;
1338                 }
1339         }
1340
1341         return 0;
1342 }
1343
1344
1345 /* Hook functions begin here. */
1346
1347 static int selinux_ptrace(struct task_struct *parent, struct task_struct *child)
1348 {
1349         struct task_security_struct *psec = parent->security;
1350         struct task_security_struct *csec = child->security;
1351         int rc;
1352
1353         rc = secondary_ops->ptrace(parent,child);
1354         if (rc)
1355                 return rc;
1356
1357         rc = task_has_perm(parent, child, PROCESS__PTRACE);
1358         /* Save the SID of the tracing process for later use in apply_creds. */
1359         if (!rc)
1360                 csec->ptrace_sid = psec->sid;
1361         return rc;
1362 }
1363
1364 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1365                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1366 {
1367         int error;
1368
1369         error = task_has_perm(current, target, PROCESS__GETCAP);
1370         if (error)
1371                 return error;
1372
1373         return secondary_ops->capget(target, effective, inheritable, permitted);
1374 }
1375
1376 static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective,
1377                                 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1378 {
1379         int error;
1380
1381         error = secondary_ops->capset_check(target, effective, inheritable, permitted);
1382         if (error)
1383                 return error;
1384
1385         return task_has_perm(current, target, PROCESS__SETCAP);
1386 }
1387
1388 static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective,
1389                                kernel_cap_t *inheritable, kernel_cap_t *permitted)
1390 {
1391         secondary_ops->capset_set(target, effective, inheritable, permitted);
1392 }
1393
1394 static int selinux_capable(struct task_struct *tsk, int cap)
1395 {
1396         int rc;
1397
1398         rc = secondary_ops->capable(tsk, cap);
1399         if (rc)
1400                 return rc;
1401
1402         return task_has_capability(tsk,cap);
1403 }
1404
1405 static int selinux_sysctl(ctl_table *table, int op)
1406 {
1407         int error = 0;
1408         u32 av;
1409         struct task_security_struct *tsec;
1410         u32 tsid;
1411         int rc;
1412
1413         rc = secondary_ops->sysctl(table, op);
1414         if (rc)
1415                 return rc;
1416
1417         tsec = current->security;
1418
1419         rc = selinux_proc_get_sid(table->de, (op == 001) ?
1420                                   SECCLASS_DIR : SECCLASS_FILE, &tsid);
1421         if (rc) {
1422                 /* Default to the well-defined sysctl SID. */
1423                 tsid = SECINITSID_SYSCTL;
1424         }
1425
1426         /* The op values are "defined" in sysctl.c, thereby creating
1427          * a bad coupling between this module and sysctl.c */
1428         if(op == 001) {
1429                 error = avc_has_perm(tsec->sid, tsid,
1430                                      SECCLASS_DIR, DIR__SEARCH, NULL);
1431         } else {
1432                 av = 0;
1433                 if (op & 004)
1434                         av |= FILE__READ;
1435                 if (op & 002)
1436                         av |= FILE__WRITE;
1437                 if (av)
1438                         error = avc_has_perm(tsec->sid, tsid,
1439                                              SECCLASS_FILE, av, NULL);
1440         }
1441
1442         return error;
1443 }
1444
1445 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1446 {
1447         int rc = 0;
1448
1449         if (!sb)
1450                 return 0;
1451
1452         switch (cmds) {
1453                 case Q_SYNC:
1454                 case Q_QUOTAON:
1455                 case Q_QUOTAOFF:
1456                 case Q_SETINFO:
1457                 case Q_SETQUOTA:
1458                         rc = superblock_has_perm(current,
1459                                                  sb,
1460                                                  FILESYSTEM__QUOTAMOD, NULL);
1461                         break;
1462                 case Q_GETFMT:
1463                 case Q_GETINFO:
1464                 case Q_GETQUOTA:
1465                         rc = superblock_has_perm(current,
1466                                                  sb,
1467                                                  FILESYSTEM__QUOTAGET, NULL);
1468                         break;
1469                 default:
1470                         rc = 0;  /* let the kernel handle invalid cmds */
1471                         break;
1472         }
1473         return rc;
1474 }
1475
1476 static int selinux_quota_on(struct dentry *dentry)
1477 {
1478         return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);
1479 }
1480
1481 static int selinux_syslog(int type)
1482 {
1483         int rc;
1484
1485         rc = secondary_ops->syslog(type);
1486         if (rc)
1487                 return rc;
1488
1489         switch (type) {
1490                 case 3:         /* Read last kernel messages */
1491                 case 10:        /* Return size of the log buffer */
1492                         rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1493                         break;
1494                 case 6:         /* Disable logging to console */
1495                 case 7:         /* Enable logging to console */
1496                 case 8:         /* Set level of messages printed to console */
1497                         rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1498                         break;
1499                 case 0:         /* Close log */
1500                 case 1:         /* Open log */
1501                 case 2:         /* Read from log */
1502                 case 4:         /* Read/clear last kernel messages */
1503                 case 5:         /* Clear ring buffer */
1504                 default:
1505                         rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1506                         break;
1507         }
1508         return rc;
1509 }
1510
1511 /*
1512  * Check that a process has enough memory to allocate a new virtual
1513  * mapping. 0 means there is enough memory for the allocation to
1514  * succeed and -ENOMEM implies there is not.
1515  *
1516  * Note that secondary_ops->capable and task_has_perm_noaudit return 0
1517  * if the capability is granted, but __vm_enough_memory requires 1 if
1518  * the capability is granted.
1519  *
1520  * Do not audit the selinux permission check, as this is applied to all
1521  * processes that allocate mappings.
1522  */
1523 static int selinux_vm_enough_memory(long pages)
1524 {
1525         int rc, cap_sys_admin = 0;
1526         struct task_security_struct *tsec = current->security;
1527
1528         rc = secondary_ops->capable(current, CAP_SYS_ADMIN);
1529         if (rc == 0)
1530                 rc = avc_has_perm_noaudit(tsec->sid, tsec->sid,
1531                                         SECCLASS_CAPABILITY,
1532                                         CAP_TO_MASK(CAP_SYS_ADMIN),
1533                                         NULL);
1534
1535         if (rc == 0)
1536                 cap_sys_admin = 1;
1537
1538         return __vm_enough_memory(pages, cap_sys_admin);
1539 }
1540
1541 /* binprm security operations */
1542
1543 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
1544 {
1545         struct bprm_security_struct *bsec;
1546
1547         bsec = kmalloc(sizeof(struct bprm_security_struct), GFP_KERNEL);
1548         if (!bsec)
1549                 return -ENOMEM;
1550
1551         memset(bsec, 0, sizeof *bsec);
1552         bsec->magic = SELINUX_MAGIC;
1553         bsec->bprm = bprm;
1554         bsec->sid = SECINITSID_UNLABELED;
1555         bsec->set = 0;
1556
1557         bprm->security = bsec;
1558         return 0;
1559 }
1560
1561 static int selinux_bprm_set_security(struct linux_binprm *bprm)
1562 {
1563         struct task_security_struct *tsec;
1564         struct inode *inode = bprm->file->f_dentry->d_inode;
1565         struct inode_security_struct *isec;
1566         struct bprm_security_struct *bsec;
1567         u32 newsid;
1568         struct avc_audit_data ad;
1569         int rc;
1570
1571         rc = secondary_ops->bprm_set_security(bprm);
1572         if (rc)
1573                 return rc;
1574
1575         bsec = bprm->security;
1576
1577         if (bsec->set)
1578                 return 0;
1579
1580         tsec = current->security;
1581         isec = inode->i_security;
1582
1583         /* Default to the current task SID. */
1584         bsec->sid = tsec->sid;
1585
1586         /* Reset create SID on execve. */
1587         tsec->create_sid = 0;
1588
1589         if (tsec->exec_sid) {
1590                 newsid = tsec->exec_sid;
1591                 /* Reset exec SID on execve. */
1592                 tsec->exec_sid = 0;
1593         } else {
1594                 /* Check for a default transition on this program. */
1595                 rc = security_transition_sid(tsec->sid, isec->sid,
1596                                              SECCLASS_PROCESS, &newsid);
1597                 if (rc)
1598                         return rc;
1599         }
1600
1601         AVC_AUDIT_DATA_INIT(&ad, FS);
1602         ad.u.fs.mnt = bprm->file->f_vfsmnt;
1603         ad.u.fs.dentry = bprm->file->f_dentry;
1604
1605         if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID)
1606                 newsid = tsec->sid;
1607
1608         if (tsec->sid == newsid) {
1609                 rc = avc_has_perm(tsec->sid, isec->sid,
1610                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
1611                 if (rc)
1612                         return rc;
1613         } else {
1614                 /* Check permissions for the transition. */
1615                 rc = avc_has_perm(tsec->sid, newsid,
1616                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
1617                 if (rc)
1618                         return rc;
1619
1620                 rc = avc_has_perm(newsid, isec->sid,
1621                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
1622                 if (rc)
1623                         return rc;
1624
1625                 /* Clear any possibly unsafe personality bits on exec: */
1626                 current->personality &= ~PER_CLEAR_ON_SETID;
1627
1628                 /* Set the security field to the new SID. */
1629                 bsec->sid = newsid;
1630         }
1631
1632         bsec->set = 1;
1633         return 0;
1634 }
1635
1636 static int selinux_bprm_check_security (struct linux_binprm *bprm)
1637 {
1638         return secondary_ops->bprm_check_security(bprm);
1639 }
1640
1641
1642 static int selinux_bprm_secureexec (struct linux_binprm *bprm)
1643 {
1644         struct task_security_struct *tsec = current->security;
1645         int atsecure = 0;
1646
1647         if (tsec->osid != tsec->sid) {
1648                 /* Enable secure mode for SIDs transitions unless
1649                    the noatsecure permission is granted between
1650                    the two SIDs, i.e. ahp returns 0. */
1651                 atsecure = avc_has_perm(tsec->osid, tsec->sid,
1652                                          SECCLASS_PROCESS,
1653                                          PROCESS__NOATSECURE, NULL);
1654         }
1655
1656         return (atsecure || secondary_ops->bprm_secureexec(bprm));
1657 }
1658
1659 static void selinux_bprm_free_security(struct linux_binprm *bprm)
1660 {
1661         struct bprm_security_struct *bsec = bprm->security;
1662         bprm->security = NULL;
1663         kfree(bsec);
1664 }
1665
1666 extern struct vfsmount *selinuxfs_mount;
1667 extern struct dentry *selinux_null;
1668
1669 /* Derived from fs/exec.c:flush_old_files. */
1670 static inline void flush_unauthorized_files(struct files_struct * files)
1671 {
1672         struct avc_audit_data ad;
1673         struct file *file, *devnull = NULL;
1674         struct tty_struct *tty = current->signal->tty;
1675         long j = -1;
1676
1677         if (tty) {
1678                 file_list_lock();
1679                 file = list_entry(tty->tty_files.next, typeof(*file), f_list);
1680                 if (file) {
1681                         /* Revalidate access to controlling tty.
1682                            Use inode_has_perm on the tty inode directly rather
1683                            than using file_has_perm, as this particular open
1684                            file may belong to another process and we are only
1685                            interested in the inode-based check here. */
1686                         struct inode *inode = file->f_dentry->d_inode;
1687                         if (inode_has_perm(current, inode,
1688                                            FILE__READ | FILE__WRITE, NULL)) {
1689                                 /* Reset controlling tty. */
1690                                 current->signal->tty = NULL;
1691                                 current->signal->tty_old_pgrp = 0;
1692                         }
1693                 }
1694                 file_list_unlock();
1695         }
1696
1697         /* Revalidate access to inherited open files. */
1698
1699         AVC_AUDIT_DATA_INIT(&ad,FS);
1700
1701         spin_lock(&files->file_lock);
1702         for (;;) {
1703                 unsigned long set, i;
1704                 int fd;
1705
1706                 j++;
1707                 i = j * __NFDBITS;
1708                 if (i >= files->max_fds || i >= files->max_fdset)
1709                         break;
1710                 set = files->open_fds->fds_bits[j];
1711                 if (!set)
1712                         continue;
1713                 spin_unlock(&files->file_lock);
1714                 for ( ; set ; i++,set >>= 1) {
1715                         if (set & 1) {
1716                                 file = fget(i);
1717                                 if (!file)
1718                                         continue;
1719                                 if (file_has_perm(current,
1720                                                   file,
1721                                                   file_to_av(file))) {
1722                                         sys_close(i);
1723                                         fd = get_unused_fd();
1724                                         if (fd != i) {
1725                                                 if (fd >= 0)
1726                                                         put_unused_fd(fd);
1727                                                 fput(file);
1728                                                 continue;
1729                                         }
1730                                         if (devnull) {
1731                                                 atomic_inc(&devnull->f_count);
1732                                         } else {
1733                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
1734                                                 if (!devnull) {
1735                                                         put_unused_fd(fd);
1736                                                         fput(file);
1737                                                         continue;
1738                                                 }
1739                                         }
1740                                         fd_install(fd, devnull);
1741                                 }
1742                                 fput(file);
1743                         }
1744                 }
1745                 spin_lock(&files->file_lock);
1746
1747         }
1748         spin_unlock(&files->file_lock);
1749 }
1750
1751 static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
1752 {
1753         struct task_security_struct *tsec;
1754         struct bprm_security_struct *bsec;
1755         u32 sid;
1756         int rc;
1757
1758         secondary_ops->bprm_apply_creds(bprm, unsafe);
1759
1760         tsec = current->security;
1761
1762         bsec = bprm->security;
1763         sid = bsec->sid;
1764
1765         tsec->osid = tsec->sid;
1766         bsec->unsafe = 0;
1767         if (tsec->sid != sid) {
1768                 /* Check for shared state.  If not ok, leave SID
1769                    unchanged and kill. */
1770                 if (unsafe & LSM_UNSAFE_SHARE) {
1771                         rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
1772                                         PROCESS__SHARE, NULL);
1773                         if (rc) {
1774                                 bsec->unsafe = 1;
1775                                 return;
1776                         }
1777                 }
1778
1779                 /* Check for ptracing, and update the task SID if ok.
1780                    Otherwise, leave SID unchanged and kill. */
1781                 if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
1782                         rc = avc_has_perm(tsec->ptrace_sid, sid,
1783                                           SECCLASS_PROCESS, PROCESS__PTRACE,
1784                                           NULL);
1785                         if (rc) {
1786                                 bsec->unsafe = 1;
1787                                 return;
1788                         }
1789                 }
1790                 tsec->sid = sid;
1791         }
1792 }
1793
1794 /*
1795  * called after apply_creds without the task lock held
1796  */
1797 static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
1798 {
1799         struct task_security_struct *tsec;
1800         struct rlimit *rlim, *initrlim;
1801         struct itimerval itimer;
1802         struct bprm_security_struct *bsec;
1803         int rc, i;
1804
1805         tsec = current->security;
1806         bsec = bprm->security;
1807
1808         if (bsec->unsafe) {
1809                 force_sig_specific(SIGKILL, current);
1810                 return;
1811         }
1812         if (tsec->osid == tsec->sid)
1813                 return;
1814
1815         /* Close files for which the new task SID is not authorized. */
1816         flush_unauthorized_files(current->files);
1817
1818         /* Check whether the new SID can inherit signal state
1819            from the old SID.  If not, clear itimers to avoid
1820            subsequent signal generation and flush and unblock
1821            signals. This must occur _after_ the task SID has
1822           been updated so that any kill done after the flush
1823           will be checked against the new SID. */
1824         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1825                           PROCESS__SIGINH, NULL);
1826         if (rc) {
1827                 memset(&itimer, 0, sizeof itimer);
1828                 for (i = 0; i < 3; i++)
1829                         do_setitimer(i, &itimer, NULL);
1830                 flush_signals(current);
1831                 spin_lock_irq(&current->sighand->siglock);
1832                 flush_signal_handlers(current, 1);
1833                 sigemptyset(&current->blocked);
1834                 recalc_sigpending();
1835                 spin_unlock_irq(&current->sighand->siglock);
1836         }
1837
1838         /* Check whether the new SID can inherit resource limits
1839            from the old SID.  If not, reset all soft limits to
1840            the lower of the current task's hard limit and the init
1841            task's soft limit.  Note that the setting of hard limits
1842            (even to lower them) can be controlled by the setrlimit
1843            check. The inclusion of the init task's soft limit into
1844            the computation is to avoid resetting soft limits higher
1845            than the default soft limit for cases where the default
1846            is lower than the hard limit, e.g. RLIMIT_CORE or
1847            RLIMIT_STACK.*/
1848         rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS,
1849                           PROCESS__RLIMITINH, NULL);
1850         if (rc) {
1851                 for (i = 0; i < RLIM_NLIMITS; i++) {
1852                         rlim = current->signal->rlim + i;
1853                         initrlim = init_task.signal->rlim+i;
1854                         rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur);
1855                 }
1856                 if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
1857                         /*
1858                          * This will cause RLIMIT_CPU calculations
1859                          * to be refigured.
1860                          */
1861                         current->it_prof_expires = jiffies_to_cputime(1);
1862                 }
1863         }
1864
1865         /* Wake up the parent if it is waiting so that it can
1866            recheck wait permission to the new task SID. */
1867         wake_up_interruptible(&current->parent->signal->wait_chldexit);
1868 }
1869
1870 /* superblock security operations */
1871
1872 static int selinux_sb_alloc_security(struct super_block *sb)
1873 {
1874         return superblock_alloc_security(sb);
1875 }
1876
1877 static void selinux_sb_free_security(struct super_block *sb)
1878 {
1879         superblock_free_security(sb);
1880 }
1881
1882 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
1883 {
1884         if (plen > olen)
1885                 return 0;
1886
1887         return !memcmp(prefix, option, plen);
1888 }
1889
1890 static inline int selinux_option(char *option, int len)
1891 {
1892         return (match_prefix("context=", sizeof("context=")-1, option, len) ||
1893                 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
1894                 match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
1895 }
1896
1897 static inline void take_option(char **to, char *from, int *first, int len)
1898 {
1899         if (!*first) {
1900                 **to = ',';
1901                 *to += 1;
1902         }
1903         else
1904                 *first = 0;
1905         memcpy(*to, from, len);
1906         *to += len;
1907 }
1908
1909 static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
1910 {
1911         int fnosec, fsec, rc = 0;
1912         char *in_save, *in_curr, *in_end;
1913         char *sec_curr, *nosec_save, *nosec;
1914
1915         in_curr = orig;
1916         sec_curr = copy;
1917
1918         /* Binary mount data: just copy */
1919         if (type->fs_flags & FS_BINARY_MOUNTDATA) {
1920                 copy_page(sec_curr, in_curr);
1921                 goto out;
1922         }
1923
1924         nosec = (char *)get_zeroed_page(GFP_KERNEL);
1925         if (!nosec) {
1926                 rc = -ENOMEM;
1927                 goto out;
1928         }
1929
1930         nosec_save = nosec;
1931         fnosec = fsec = 1;
1932         in_save = in_end = orig;
1933
1934         do {
1935                 if (*in_end == ',' || *in_end == '\0') {
1936                         int len = in_end - in_curr;
1937
1938                         if (selinux_option(in_curr, len))
1939                                 take_option(&sec_curr, in_curr, &fsec, len);
1940                         else
1941                                 take_option(&nosec, in_curr, &fnosec, len);
1942
1943                         in_curr = in_end + 1;
1944                 }
1945         } while (*in_end++);
1946
1947         copy_page(in_save, nosec_save);
1948 out:
1949         return rc;
1950 }
1951
1952 static int selinux_sb_kern_mount(struct super_block *sb, void *data)
1953 {
1954         struct avc_audit_data ad;
1955         int rc;
1956
1957         rc = superblock_doinit(sb, data);
1958         if (rc)
1959                 return rc;
1960
1961         AVC_AUDIT_DATA_INIT(&ad,FS);
1962         ad.u.fs.dentry = sb->s_root;
1963         return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
1964 }
1965
1966 static int selinux_sb_statfs(struct super_block *sb)
1967 {
1968         struct avc_audit_data ad;
1969
1970         AVC_AUDIT_DATA_INIT(&ad,FS);
1971         ad.u.fs.dentry = sb->s_root;
1972         return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad);
1973 }
1974
1975 static int selinux_mount(char * dev_name,
1976                          struct nameidata *nd,
1977                          char * type,
1978                          unsigned long flags,
1979                          void * data)
1980 {
1981         int rc;
1982
1983         rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data);
1984         if (rc)
1985                 return rc;
1986
1987         if (flags & MS_REMOUNT)
1988                 return superblock_has_perm(current, nd->mnt->mnt_sb,
1989                                            FILESYSTEM__REMOUNT, NULL);
1990         else
1991                 return dentry_has_perm(current, nd->mnt, nd->dentry,
1992                                        FILE__MOUNTON);
1993 }
1994
1995 static int selinux_umount(struct vfsmount *mnt, int flags)
1996 {
1997         int rc;
1998
1999         rc = secondary_ops->sb_umount(mnt, flags);
2000         if (rc)
2001                 return rc;
2002
2003         return superblock_has_perm(current,mnt->mnt_sb,
2004                                    FILESYSTEM__UNMOUNT,NULL);
2005 }
2006
2007 /* inode security operations */
2008
2009 static int selinux_inode_alloc_security(struct inode *inode)
2010 {
2011         return inode_alloc_security(inode);
2012 }
2013
2014 static void selinux_inode_free_security(struct inode *inode)
2015 {
2016         inode_free_security(inode);
2017 }
2018
2019 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2020 {
2021         return may_create(dir, dentry, SECCLASS_FILE);
2022 }
2023
2024 static void selinux_inode_post_create(struct inode *dir, struct dentry *dentry, int mask)
2025 {
2026         post_create(dir, dentry);
2027 }
2028
2029 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2030 {
2031         int rc;
2032
2033         rc = secondary_ops->inode_link(old_dentry,dir,new_dentry);
2034         if (rc)
2035                 return rc;
2036         return may_link(dir, old_dentry, MAY_LINK);
2037 }
2038
2039 static void selinux_inode_post_link(struct dentry *old_dentry, struct inode *inode, struct dentry *new_dentry)
2040 {
2041         return;
2042 }
2043
2044 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2045 {
2046         int rc;
2047
2048         rc = secondary_ops->inode_unlink(dir, dentry);
2049         if (rc)
2050                 return rc;
2051         return may_link(dir, dentry, MAY_UNLINK);
2052 }
2053
2054 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2055 {
2056         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2057 }
2058
2059 static void selinux_inode_post_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2060 {
2061         post_create(dir, dentry);
2062 }
2063
2064 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2065 {
2066         return may_create(dir, dentry, SECCLASS_DIR);
2067 }
2068
2069 static void selinux_inode_post_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2070 {
2071         post_create(dir, dentry);
2072 }
2073
2074 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2075 {
2076         return may_link(dir, dentry, MAY_RMDIR);
2077 }
2078
2079 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2080 {
2081         int rc;
2082
2083         rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
2084         if (rc)
2085                 return rc;
2086
2087         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2088 }
2089
2090 static void selinux_inode_post_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2091 {
2092         post_create(dir, dentry);
2093 }
2094
2095 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2096                                 struct inode *new_inode, struct dentry *new_dentry)
2097 {
2098         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2099 }
2100
2101 static void selinux_inode_post_rename(struct inode *old_inode, struct dentry *old_dentry,
2102                                       struct inode *new_inode, struct dentry *new_dentry)
2103 {
2104         return;
2105 }
2106
2107 static int selinux_inode_readlink(struct dentry *dentry)
2108 {
2109         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2110 }
2111
2112 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2113 {
2114         int rc;
2115
2116         rc = secondary_ops->inode_follow_link(dentry,nameidata);
2117         if (rc)
2118                 return rc;
2119         return dentry_has_perm(current, NULL, dentry, FILE__READ);
2120 }
2121
2122 static int selinux_inode_permission(struct inode *inode, int mask,
2123                                     struct nameidata *nd)
2124 {
2125         int rc;
2126
2127         rc = secondary_ops->inode_permission(inode, mask, nd);
2128         if (rc)
2129                 return rc;
2130
2131         if (!mask) {
2132                 /* No permission to check.  Existence test. */
2133                 return 0;
2134         }
2135
2136         return inode_has_perm(current, inode,
2137                                file_mask_to_av(inode->i_mode, mask), NULL);
2138 }
2139
2140 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2141 {
2142         int rc;
2143
2144         rc = secondary_ops->inode_setattr(dentry, iattr);
2145         if (rc)
2146                 return rc;
2147
2148         if (iattr->ia_valid & ATTR_FORCE)
2149                 return 0;
2150
2151         if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2152                                ATTR_ATIME_SET | ATTR_MTIME_SET))
2153                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2154
2155         return dentry_has_perm(current, NULL, dentry, FILE__WRITE);
2156 }
2157
2158 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2159 {
2160         return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
2161 }
2162
2163 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags)
2164 {
2165         struct task_security_struct *tsec = current->security;
2166         struct inode *inode = dentry->d_inode;
2167         struct inode_security_struct *isec = inode->i_security;
2168         struct superblock_security_struct *sbsec;
2169         struct avc_audit_data ad;
2170         u32 newsid;
2171         int rc = 0;
2172
2173         if (strcmp(name, XATTR_NAME_SELINUX)) {
2174                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2175                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2176                     !capable(CAP_SYS_ADMIN)) {
2177                         /* A different attribute in the security namespace.
2178                            Restrict to administrator. */
2179                         return -EPERM;
2180                 }
2181
2182                 /* Not an attribute we recognize, so just check the
2183                    ordinary setattr permission. */
2184                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2185         }
2186
2187         sbsec = inode->i_sb->s_security;
2188         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2189                 return -EOPNOTSUPP;
2190
2191         if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
2192                 return -EPERM;
2193
2194         AVC_AUDIT_DATA_INIT(&ad,FS);
2195         ad.u.fs.dentry = dentry;
2196
2197         rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
2198                           FILE__RELABELFROM, &ad);
2199         if (rc)
2200                 return rc;
2201
2202         rc = security_context_to_sid(value, size, &newsid);
2203         if (rc)
2204                 return rc;
2205
2206         rc = avc_has_perm(tsec->sid, newsid, isec->sclass,
2207                           FILE__RELABELTO, &ad);
2208         if (rc)
2209                 return rc;
2210
2211         rc = security_validate_transition(isec->sid, newsid, tsec->sid,
2212                                           isec->sclass);
2213         if (rc)
2214                 return rc;
2215
2216         return avc_has_perm(newsid,
2217                             sbsec->sid,
2218                             SECCLASS_FILESYSTEM,
2219                             FILESYSTEM__ASSOCIATE,
2220                             &ad);
2221 }
2222
2223 static void selinux_inode_post_setxattr(struct dentry *dentry, char *name,
2224                                         void *value, size_t size, int flags)
2225 {
2226         struct inode *inode = dentry->d_inode;
2227         struct inode_security_struct *isec = inode->i_security;
2228         u32 newsid;
2229         int rc;
2230
2231         if (strcmp(name, XATTR_NAME_SELINUX)) {
2232                 /* Not an attribute we recognize, so nothing to do. */
2233                 return;
2234         }
2235
2236         rc = security_context_to_sid(value, size, &newsid);
2237         if (rc) {
2238                 printk(KERN_WARNING "%s:  unable to obtain SID for context "
2239                        "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc);
2240                 return;
2241         }
2242
2243         isec->sid = newsid;
2244         return;
2245 }
2246
2247 static int selinux_inode_getxattr (struct dentry *dentry, char *name)
2248 {
2249         struct inode *inode = dentry->d_inode;
2250         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
2251
2252         if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2253                 return -EOPNOTSUPP;
2254
2255         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2256 }
2257
2258 static int selinux_inode_listxattr (struct dentry *dentry)
2259 {
2260         return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);
2261 }
2262
2263 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
2264 {
2265         if (strcmp(name, XATTR_NAME_SELINUX)) {
2266                 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2267                              sizeof XATTR_SECURITY_PREFIX - 1) &&
2268                     !capable(CAP_SYS_ADMIN)) {
2269                         /* A different attribute in the security namespace.
2270                            Restrict to administrator. */
2271                         return -EPERM;
2272                 }
2273
2274                 /* Not an attribute we recognize, so just check the
2275                    ordinary setattr permission. Might want a separate
2276                    permission for removexattr. */
2277                 return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
2278         }
2279
2280         /* No one is allowed to remove a SELinux security label.
2281            You can change the label, but all data must be labeled. */
2282         return -EACCES;
2283 }
2284
2285 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void *buffer, size_t size)
2286 {
2287         struct inode_security_struct *isec = inode->i_security;
2288         char *context;
2289         unsigned len;
2290         int rc;
2291
2292         /* Permission check handled by selinux_inode_getxattr hook.*/
2293
2294         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2295                 return -EOPNOTSUPP;
2296
2297         rc = security_sid_to_context(isec->sid, &context, &len);
2298         if (rc)
2299                 return rc;
2300
2301         if (!buffer || !size) {
2302                 kfree(context);
2303                 return len;
2304         }
2305         if (size < len) {
2306                 kfree(context);
2307                 return -ERANGE;
2308         }
2309         memcpy(buffer, context, len);
2310         kfree(context);
2311         return len;
2312 }
2313
2314 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2315                                      const void *value, size_t size, int flags)
2316 {
2317         struct inode_security_struct *isec = inode->i_security;
2318         u32 newsid;
2319         int rc;
2320
2321         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2322                 return -EOPNOTSUPP;
2323
2324         if (!value || !size)
2325                 return -EACCES;
2326
2327         rc = security_context_to_sid((void*)value, size, &newsid);
2328         if (rc)
2329                 return rc;
2330
2331         isec->sid = newsid;
2332         return 0;
2333 }
2334
2335 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2336 {
2337         const int len = sizeof(XATTR_NAME_SELINUX);
2338         if (buffer && len <= buffer_size)
2339                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2340         return len;
2341 }
2342
2343 /* file security operations */
2344
2345 static int selinux_file_permission(struct file *file, int mask)
2346 {
2347         struct inode *inode = file->f_dentry->d_inode;
2348
2349         if (!mask) {
2350                 /* No permission to check.  Existence test. */
2351                 return 0;
2352         }
2353
2354         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2355         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2356                 mask |= MAY_APPEND;
2357
2358         return file_has_perm(current, file,
2359                              file_mask_to_av(inode->i_mode, mask));
2360 }
2361
2362 static int selinux_file_alloc_security(struct file *file)
2363 {
2364         return file_alloc_security(file);
2365 }
2366
2367 static void selinux_file_free_security(struct file *file)
2368 {
2369         file_free_security(file);
2370 }
2371
2372 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2373                               unsigned long arg)
2374 {
2375         int error = 0;
2376
2377         switch (cmd) {
2378                 case FIONREAD:
2379                 /* fall through */
2380                 case FIBMAP:
2381                 /* fall through */
2382                 case FIGETBSZ:
2383                 /* fall through */
2384                 case EXT2_IOC_GETFLAGS:
2385                 /* fall through */
2386                 case EXT2_IOC_GETVERSION:
2387                         error = file_has_perm(current, file, FILE__GETATTR);
2388                         break;
2389
2390                 case EXT2_IOC_SETFLAGS:
2391                 /* fall through */
2392                 case EXT2_IOC_SETVERSION:
2393                         error = file_has_perm(current, file, FILE__SETATTR);
2394                         break;
2395
2396                 /* sys_ioctl() checks */
2397                 case FIONBIO:
2398                 /* fall through */
2399                 case FIOASYNC:
2400                         error = file_has_perm(current, file, 0);
2401                         break;
2402
2403                 case KDSKBENT:
2404                 case KDSKBSENT:
2405                         error = task_has_capability(current,CAP_SYS_TTY_CONFIG);
2406                         break;
2407
2408                 /* default case assumes that the command will go
2409                  * to the file's ioctl() function.
2410                  */
2411                 default:
2412                         error = file_has_perm(current, file, FILE__IOCTL);
2413
2414         }
2415         return error;
2416 }
2417
2418 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2419 {
2420 #ifndef CONFIG_PPC32
2421         if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2422                 /*
2423                  * We are making executable an anonymous mapping or a
2424                  * private file mapping that will also be writable.
2425                  * This has an additional check.
2426                  */
2427                 int rc = task_has_perm(current, current, PROCESS__EXECMEM);
2428                 if (rc)
2429                         return rc;
2430         }
2431 #endif
2432
2433         if (file) {
2434                 /* read access is always possible with a mapping */
2435                 u32 av = FILE__READ;
2436
2437                 /* write access only matters if the mapping is shared */
2438                 if (shared && (prot & PROT_WRITE))
2439                         av |= FILE__WRITE;
2440
2441                 if (prot & PROT_EXEC)
2442                         av |= FILE__EXECUTE;
2443
2444                 return file_has_perm(current, file, av);
2445         }
2446         return 0;
2447 }
2448
2449 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
2450                              unsigned long prot, unsigned long flags)
2451 {
2452         int rc;
2453
2454         rc = secondary_ops->file_mmap(file, reqprot, prot, flags);
2455         if (rc)
2456                 return rc;
2457
2458         if (selinux_checkreqprot)
2459                 prot = reqprot;
2460
2461         return file_map_prot_check(file, prot,
2462                                    (flags & MAP_TYPE) == MAP_SHARED);
2463 }
2464
2465 static int selinux_file_mprotect(struct vm_area_struct *vma,
2466                                  unsigned long reqprot,
2467                                  unsigned long prot)
2468 {
2469         int rc;
2470
2471         rc = secondary_ops->file_mprotect(vma, reqprot, prot);
2472         if (rc)
2473                 return rc;
2474
2475         if (selinux_checkreqprot)
2476                 prot = reqprot;
2477
2478 #ifndef CONFIG_PPC32
2479         if (vma->vm_file != NULL && vma->anon_vma != NULL && (prot & PROT_EXEC)) {
2480                 /*
2481                  * We are making executable a file mapping that has
2482                  * had some COW done. Since pages might have been written,
2483                  * check ability to execute the possibly modified content.
2484                  * This typically should only occur for text relocations.
2485                  */
2486                 int rc = file_has_perm(current, vma->vm_file, FILE__EXECMOD);
2487                 if (rc)
2488                         return rc;
2489         }
2490 #endif
2491
2492         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
2493 }
2494
2495 static int selinux_file_lock(struct file *file, unsigned int cmd)
2496 {
2497         return file_has_perm(current, file, FILE__LOCK);
2498 }
2499
2500 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
2501                               unsigned long arg)
2502 {
2503         int err = 0;
2504
2505         switch (cmd) {
2506                 case F_SETFL:
2507                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2508                                 err = -EINVAL;
2509                                 break;
2510                         }
2511
2512                         if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
2513                                 err = file_has_perm(current, file,FILE__WRITE);
2514                                 break;
2515                         }
2516                         /* fall through */
2517                 case F_SETOWN:
2518                 case F_SETSIG:
2519                 case F_GETFL:
2520                 case F_GETOWN:
2521                 case F_GETSIG:
2522                         /* Just check FD__USE permission */
2523                         err = file_has_perm(current, file, 0);
2524                         break;
2525                 case F_GETLK:
2526                 case F_SETLK:
2527                 case F_SETLKW:
2528 #if BITS_PER_LONG == 32
2529                 case F_GETLK64:
2530                 case F_SETLK64:
2531                 case F_SETLKW64:
2532 #endif
2533                         if (!file->f_dentry || !file->f_dentry->d_inode) {
2534                                 err = -EINVAL;
2535                                 break;
2536                         }
2537                         err = file_has_perm(current, file, FILE__LOCK);
2538                         break;
2539         }
2540
2541         return err;
2542 }
2543
2544 static int selinux_file_set_fowner(struct file *file)
2545 {
2546         struct task_security_struct *tsec;
2547         struct file_security_struct *fsec;
2548
2549         tsec = current->security;
2550         fsec = file->f_security;
2551         fsec->fown_sid = tsec->sid;
2552
2553         return 0;
2554 }
2555
2556 static int selinux_file_send_sigiotask(struct task_struct *tsk,
2557                                        struct fown_struct *fown, int signum)
2558 {
2559         struct file *file;
2560         u32 perm;
2561         struct task_security_struct *tsec;
2562         struct file_security_struct *fsec;
2563
2564         /* struct fown_struct is never outside the context of a struct file */
2565         file = (struct file *)((long)fown - offsetof(struct file,f_owner));
2566
2567         tsec = tsk->security;
2568         fsec = file->f_security;
2569
2570         if (!signum)
2571                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
2572         else
2573                 perm = signal_to_av(signum);
2574
2575         return avc_has_perm(fsec->fown_sid, tsec->sid,
2576                             SECCLASS_PROCESS, perm, NULL);
2577 }
2578
2579 static int selinux_file_receive(struct file *file)
2580 {
2581         return file_has_perm(current, file, file_to_av(file));
2582 }
2583
2584 /* task security operations */
2585
2586 static int selinux_task_create(unsigned long clone_flags)
2587 {
2588         int rc;
2589
2590         rc = secondary_ops->task_create(clone_flags);
2591         if (rc)
2592                 return rc;
2593
2594         return task_has_perm(current, current, PROCESS__FORK);
2595 }
2596
2597 static int selinux_task_alloc_security(struct task_struct *tsk)
2598 {
2599         struct task_security_struct *tsec1, *tsec2;
2600         int rc;
2601
2602         tsec1 = current->security;
2603
2604         rc = task_alloc_security(tsk);
2605         if (rc)
2606                 return rc;
2607         tsec2 = tsk->security;
2608
2609         tsec2->osid = tsec1->osid;
2610         tsec2->sid = tsec1->sid;
2611
2612         /* Retain the exec and create SIDs across fork */
2613         tsec2->exec_sid = tsec1->exec_sid;
2614         tsec2->create_sid = tsec1->create_sid;
2615
2616         /* Retain ptracer SID across fork, if any.
2617            This will be reset by the ptrace hook upon any
2618            subsequent ptrace_attach operations. */
2619         tsec2->ptrace_sid = tsec1->ptrace_sid;
2620
2621         return 0;
2622 }
2623
2624 static void selinux_task_free_security(struct task_struct *tsk)
2625 {
2626         task_free_security(tsk);
2627 }
2628
2629 static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2630 {
2631         /* Since setuid only affects the current process, and
2632            since the SELinux controls are not based on the Linux
2633            identity attributes, SELinux does not need to control
2634            this operation.  However, SELinux does control the use
2635            of the CAP_SETUID and CAP_SETGID capabilities using the
2636            capable hook. */
2637         return 0;
2638 }
2639
2640 static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
2641 {
2642         return secondary_ops->task_post_setuid(id0,id1,id2,flags);
2643 }
2644
2645 static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
2646 {
2647         /* See the comment for setuid above. */
2648         return 0;
2649 }
2650
2651 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
2652 {
2653         return task_has_perm(current, p, PROCESS__SETPGID);
2654 }
2655
2656 static int selinux_task_getpgid(struct task_struct *p)
2657 {
2658         return task_has_perm(current, p, PROCESS__GETPGID);
2659 }
2660
2661 static int selinux_task_getsid(struct task_struct *p)
2662 {
2663         return task_has_perm(current, p, PROCESS__GETSESSION);
2664 }
2665
2666 static int selinux_task_setgroups(struct group_info *group_info)
2667 {
2668         /* See the comment for setuid above. */
2669         return 0;
2670 }
2671
2672 static int selinux_task_setnice(struct task_struct *p, int nice)
2673 {
2674         int rc;
2675
2676         rc = secondary_ops->task_setnice(p, nice);
2677         if (rc)
2678                 return rc;
2679
2680         return task_has_perm(current,p, PROCESS__SETSCHED);
2681 }
2682
2683 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
2684 {
2685         struct rlimit *old_rlim = current->signal->rlim + resource;
2686         int rc;
2687
2688         rc = secondary_ops->task_setrlimit(resource, new_rlim);
2689         if (rc)
2690                 return rc;
2691
2692         /* Control the ability to change the hard limit (whether
2693            lowering or raising it), so that the hard limit can
2694            later be used as a safe reset point for the soft limit
2695            upon context transitions. See selinux_bprm_apply_creds. */
2696         if (old_rlim->rlim_max != new_rlim->rlim_max)
2697                 return task_has_perm(current, current, PROCESS__SETRLIMIT);
2698
2699         return 0;
2700 }
2701
2702 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
2703 {
2704         return task_has_perm(current, p, PROCESS__SETSCHED);
2705 }
2706
2707 static int selinux_task_getscheduler(struct task_struct *p)
2708 {
2709         return task_has_perm(current, p, PROCESS__GETSCHED);
2710 }
2711
2712 static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
2713 {
2714         u32 perm;
2715         int rc;
2716
2717         rc = secondary_ops->task_kill(p, info, sig);
2718         if (rc)
2719                 return rc;
2720
2721         if (info && ((unsigned long)info == 1 ||
2722                      (unsigned long)info == 2 || SI_FROMKERNEL(info)))
2723                 return 0;
2724
2725         if (!sig)
2726                 perm = PROCESS__SIGNULL; /* null signal; existence test */
2727         else
2728                 perm = signal_to_av(sig);
2729
2730         return task_has_perm(current, p, perm);
2731 }
2732
2733 static int selinux_task_prctl(int option,
2734                               unsigned long arg2,
2735                               unsigned long arg3,
2736                               unsigned long arg4,
2737                               unsigned long arg5)
2738 {
2739         /* The current prctl operations do not appear to require
2740            any SELinux controls since they merely observe or modify
2741            the state of the current process. */
2742         return 0;
2743 }
2744
2745 static int selinux_task_wait(struct task_struct *p)
2746 {
2747         u32 perm;
2748
2749         perm = signal_to_av(p->exit_signal);
2750
2751         return task_has_perm(p, current, perm);
2752 }
2753
2754 static void selinux_task_reparent_to_init(struct task_struct *p)
2755 {
2756         struct task_security_struct *tsec;
2757
2758         secondary_ops->task_reparent_to_init(p);
2759
2760         tsec = p->security;
2761         tsec->osid = tsec->sid;
2762         tsec->sid = SECINITSID_KERNEL;
2763         return;
2764 }
2765
2766 static void selinux_task_to_inode(struct task_struct *p,
2767                                   struct inode *inode)
2768 {
2769         struct task_security_struct *tsec = p->security;
2770         struct inode_security_struct *isec = inode->i_security;
2771
2772         isec->sid = tsec->sid;
2773         isec->initialized = 1;
2774         return;
2775 }
2776
2777 #ifdef CONFIG_SECURITY_NETWORK
2778
2779 /* Returns error only if unable to parse addresses */
2780 static int selinux_parse_skb_ipv4(struct sk_buff *skb, struct avc_audit_data *ad)
2781 {
2782         int offset, ihlen, ret = -EINVAL;
2783         struct iphdr _iph, *ih;
2784
2785         offset = skb->nh.raw - skb->data;
2786         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
2787         if (ih == NULL)
2788                 goto out;
2789
2790         ihlen = ih->ihl * 4;
2791         if (ihlen < sizeof(_iph))
2792                 goto out;
2793
2794         ad->u.net.v4info.saddr = ih->saddr;
2795         ad->u.net.v4info.daddr = ih->daddr;
2796         ret = 0;
2797
2798         switch (ih->protocol) {
2799         case IPPROTO_TCP: {
2800                 struct tcphdr _tcph, *th;
2801
2802                 if (ntohs(ih->frag_off) & IP_OFFSET)
2803                         break;
2804
2805                 offset += ihlen;
2806                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2807                 if (th == NULL)
2808                         break;
2809
2810                 ad->u.net.sport = th->source;
2811                 ad->u.net.dport = th->dest;
2812                 break;
2813         }
2814         
2815         case IPPROTO_UDP: {
2816                 struct udphdr _udph, *uh;
2817                 
2818                 if (ntohs(ih->frag_off) & IP_OFFSET)
2819                         break;
2820                         
2821                 offset += ihlen;
2822                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2823                 if (uh == NULL)
2824                         break;  
2825
2826                 ad->u.net.sport = uh->source;
2827                 ad->u.net.dport = uh->dest;
2828                 break;
2829         }
2830
2831         default:
2832                 break;
2833         }
2834 out:
2835         return ret;
2836 }
2837
2838 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2839
2840 /* Returns error only if unable to parse addresses */
2841 static int selinux_parse_skb_ipv6(struct sk_buff *skb, struct avc_audit_data *ad)
2842 {
2843         u8 nexthdr;
2844         int ret = -EINVAL, offset;
2845         struct ipv6hdr _ipv6h, *ip6;
2846
2847         offset = skb->nh.raw - skb->data;
2848         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
2849         if (ip6 == NULL)
2850                 goto out;
2851
2852         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
2853         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
2854         ret = 0;
2855
2856         nexthdr = ip6->nexthdr;
2857         offset += sizeof(_ipv6h);
2858         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
2859         if (offset < 0)
2860                 goto out;
2861
2862         switch (nexthdr) {
2863         case IPPROTO_TCP: {
2864                 struct tcphdr _tcph, *th;
2865
2866                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
2867                 if (th == NULL)
2868                         break;
2869
2870                 ad->u.net.sport = th->source;
2871                 ad->u.net.dport = th->dest;
2872                 break;
2873         }
2874
2875         case IPPROTO_UDP: {
2876                 struct udphdr _udph, *uh;
2877
2878                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
2879                 if (uh == NULL)
2880                         break;
2881
2882                 ad->u.net.sport = uh->source;
2883                 ad->u.net.dport = uh->dest;
2884                 break;
2885         }
2886
2887         /* includes fragments */
2888         default:
2889                 break;
2890         }
2891 out:
2892         return ret;
2893 }
2894
2895 #endif /* IPV6 */
2896
2897 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
2898                              char **addrp, int *len, int src)
2899 {
2900         int ret = 0;
2901
2902         switch (ad->u.net.family) {
2903         case PF_INET:
2904                 ret = selinux_parse_skb_ipv4(skb, ad);
2905                 if (ret || !addrp)
2906                         break;
2907                 *len = 4;
2908                 *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
2909                                         &ad->u.net.v4info.daddr);
2910                 break;
2911
2912 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
2913         case PF_INET6:
2914                 ret = selinux_parse_skb_ipv6(skb, ad);
2915                 if (ret || !addrp)
2916                         break;
2917                 *len = 16;
2918                 *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
2919                                         &ad->u.net.v6info.daddr);
2920                 break;
2921 #endif  /* IPV6 */
2922         default:
2923                 break;
2924         }
2925
2926         return ret;
2927 }
2928
2929 /* socket security operations */
2930 static int socket_has_perm(struct task_struct *task, struct socket *sock,
2931                            u32 perms)
2932 {
2933         struct inode_security_struct *isec;
2934         struct task_security_struct *tsec;
2935         struct avc_audit_data ad;
2936         int err = 0;
2937
2938         tsec = task->security;
2939         isec = SOCK_INODE(sock)->i_security;
2940
2941         if (isec->sid == SECINITSID_KERNEL)
2942                 goto out;
2943
2944         AVC_AUDIT_DATA_INIT(&ad,NET);
2945         ad.u.net.sk = sock->sk;
2946         err = avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, &ad);
2947
2948 out:
2949         return err;
2950 }
2951
2952 static int selinux_socket_create(int family, int type,
2953                                  int protocol, int kern)
2954 {
2955         int err = 0;
2956         struct task_security_struct *tsec;
2957
2958         if (kern)
2959                 goto out;
2960
2961         tsec = current->security;
2962         err = avc_has_perm(tsec->sid, tsec->sid,
2963                            socket_type_to_security_class(family, type,
2964                            protocol), SOCKET__CREATE, NULL);
2965
2966 out:
2967         return err;
2968 }
2969
2970 static void selinux_socket_post_create(struct socket *sock, int family,
2971                                        int type, int protocol, int kern)
2972 {
2973         struct inode_security_struct *isec;
2974         struct task_security_struct *tsec;
2975
2976         isec = SOCK_INODE(sock)->i_security;
2977
2978         tsec = current->security;
2979         isec->sclass = socket_type_to_security_class(family, type, protocol);
2980         isec->sid = kern ? SECINITSID_KERNEL : tsec->sid;
2981         isec->initialized = 1;
2982
2983         return;
2984 }
2985
2986 /* Range of port numbers used to automatically bind.
2987    Need to determine whether we should perform a name_bind
2988    permission check between the socket and the port number. */
2989 #define ip_local_port_range_0 sysctl_local_port_range[0]
2990 #define ip_local_port_range_1 sysctl_local_port_range[1]
2991
2992 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
2993 {
2994         u16 family;
2995         int err;
2996
2997         err = socket_has_perm(current, sock, SOCKET__BIND);
2998         if (err)
2999                 goto out;
3000
3001         /*
3002          * If PF_INET or PF_INET6, check name_bind permission for the port.
3003          */
3004         family = sock->sk->sk_family;
3005         if (family == PF_INET || family == PF_INET6) {
3006                 char *addrp;
3007                 struct inode_security_struct *isec;
3008                 struct task_security_struct *tsec;
3009                 struct avc_audit_data ad;
3010                 struct sockaddr_in *addr4 = NULL;
3011                 struct sockaddr_in6 *addr6 = NULL;
3012                 unsigned short snum;
3013                 struct sock *sk = sock->sk;
3014                 u32 sid, node_perm, addrlen;
3015
3016                 tsec = current->security;
3017                 isec = SOCK_INODE(sock)->i_security;
3018
3019                 if (family == PF_INET) {
3020                         addr4 = (struct sockaddr_in *)address;
3021                         snum = ntohs(addr4->sin_port);
3022                         addrlen = sizeof(addr4->sin_addr.s_addr);
3023                         addrp = (char *)&addr4->sin_addr.s_addr;
3024                 } else {
3025                         addr6 = (struct sockaddr_in6 *)address;
3026                         snum = ntohs(addr6->sin6_port);
3027                         addrlen = sizeof(addr6->sin6_addr.s6_addr);
3028                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3029                 }
3030
3031                 if (snum&&(snum < max(PROT_SOCK,ip_local_port_range_0) ||
3032                            snum > ip_local_port_range_1)) {
3033                         err = security_port_sid(sk->sk_family, sk->sk_type,
3034                                                 sk->sk_protocol, snum, &sid);
3035                         if (err)
3036                                 goto out;
3037                         AVC_AUDIT_DATA_INIT(&ad,NET);
3038                         ad.u.net.sport = htons(snum);
3039                         ad.u.net.family = family;
3040                         err = avc_has_perm(isec->sid, sid,
3041                                            isec->sclass,
3042                                            SOCKET__NAME_BIND, &ad);
3043                         if (err)
3044                                 goto out;
3045                 }
3046                 
3047                 switch(sk->sk_protocol) {
3048                 case IPPROTO_TCP:
3049                         node_perm = TCP_SOCKET__NODE_BIND;
3050                         break;
3051                         
3052                 case IPPROTO_UDP:
3053                         node_perm = UDP_SOCKET__NODE_BIND;
3054                         break;
3055                         
3056                 default:
3057                         node_perm = RAWIP_SOCKET__NODE_BIND;
3058                         break;
3059                 }
3060                 
3061                 err = security_node_sid(family, addrp, addrlen, &sid);
3062                 if (err)
3063                         goto out;
3064                 
3065                 AVC_AUDIT_DATA_INIT(&ad,NET);
3066                 ad.u.net.sport = htons(snum);
3067                 ad.u.net.family = family;
3068
3069                 if (family == PF_INET)
3070                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3071                 else
3072                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3073
3074                 err = avc_has_perm(isec->sid, sid,
3075                                    isec->sclass, node_perm, &ad);
3076                 if (err)
3077                         goto out;
3078         }
3079 out:
3080         return err;
3081 }
3082
3083 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3084 {
3085         struct inode_security_struct *isec;
3086         int err;
3087
3088         err = socket_has_perm(current, sock, SOCKET__CONNECT);
3089         if (err)
3090                 return err;
3091
3092         /*
3093          * If a TCP socket, check name_connect permission for the port.
3094          */
3095         isec = SOCK_INODE(sock)->i_security;
3096         if (isec->sclass == SECCLASS_TCP_SOCKET) {
3097                 struct sock *sk = sock->sk;
3098                 struct avc_audit_data ad;
3099                 struct sockaddr_in *addr4 = NULL;
3100                 struct sockaddr_in6 *addr6 = NULL;
3101                 unsigned short snum;
3102                 u32 sid;
3103
3104                 if (sk->sk_family == PF_INET) {
3105                         addr4 = (struct sockaddr_in *)address;
3106                         if (addrlen != sizeof(struct sockaddr_in))
3107                                 return -EINVAL;
3108                         snum = ntohs(addr4->sin_port);
3109                 } else {
3110                         addr6 = (struct sockaddr_in6 *)address;
3111                         if (addrlen != sizeof(struct sockaddr_in6))
3112                                 return -EINVAL;
3113                         snum = ntohs(addr6->sin6_port);
3114                 }
3115
3116                 err = security_port_sid(sk->sk_family, sk->sk_type,
3117                                         sk->sk_protocol, snum, &sid);
3118                 if (err)
3119                         goto out;
3120
3121                 AVC_AUDIT_DATA_INIT(&ad,NET);
3122                 ad.u.net.dport = htons(snum);
3123                 ad.u.net.family = sk->sk_family;
3124                 err = avc_has_perm(isec->sid, sid, isec->sclass,
3125                                    TCP_SOCKET__NAME_CONNECT, &ad);
3126                 if (err)
3127                         goto out;
3128         }
3129
3130 out:
3131         return err;
3132 }
3133
3134 static int selinux_socket_listen(struct socket *sock, int backlog)
3135 {
3136         return socket_has_perm(current, sock, SOCKET__LISTEN);
3137 }
3138
3139 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3140 {
3141         int err;
3142         struct inode_security_struct *isec;
3143         struct inode_security_struct *newisec;
3144
3145         err = socket_has_perm(current, sock, SOCKET__ACCEPT);
3146         if (err)
3147                 return err;
3148
3149         newisec = SOCK_INODE(newsock)->i_security;
3150
3151         isec = SOCK_INODE(sock)->i_security;
3152         newisec->sclass = isec->sclass;
3153         newisec->sid = isec->sid;
3154         newisec->initialized = 1;
3155
3156         return 0;
3157 }
3158
3159 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3160                                   int size)
3161 {
3162         return socket_has_perm(current, sock, SOCKET__WRITE);
3163 }
3164
3165 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3166                                   int size, int flags)
3167 {
3168         return socket_has_perm(current, sock, SOCKET__READ);
3169 }
3170
3171 static int selinux_socket_getsockname(struct socket *sock)
3172 {
3173         return socket_has_perm(current, sock, SOCKET__GETATTR);
3174 }
3175
3176 static int selinux_socket_getpeername(struct socket *sock)
3177 {
3178         return socket_has_perm(current, sock, SOCKET__GETATTR);
3179 }
3180
3181 static int selinux_socket_setsockopt(struct socket *sock,int level,int optname)
3182 {
3183         return socket_has_perm(current, sock, SOCKET__SETOPT);
3184 }
3185
3186 static int selinux_socket_getsockopt(struct socket *sock, int level,
3187                                      int optname)
3188 {
3189         return socket_has_perm(current, sock, SOCKET__GETOPT);
3190 }
3191
3192 static int selinux_socket_shutdown(struct socket *sock, int how)
3193 {
3194         return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
3195 }
3196
3197 static int selinux_socket_unix_stream_connect(struct socket *sock,
3198                                               struct socket *other,
3199                                               struct sock *newsk)
3200 {
3201         struct sk_security_struct *ssec;
3202         struct inode_security_struct *isec;
3203         struct inode_security_struct *other_isec;
3204         struct avc_audit_data ad;
3205         int err;
3206
3207         err = secondary_ops->unix_stream_connect(sock, other, newsk);
3208         if (err)
3209                 return err;
3210
3211         isec = SOCK_INODE(sock)->i_security;
3212         other_isec = SOCK_INODE(other)->i_security;
3213
3214         AVC_AUDIT_DATA_INIT(&ad,NET);
3215         ad.u.net.sk = other->sk;
3216
3217         err = avc_has_perm(isec->sid, other_isec->sid,
3218                            isec->sclass,
3219                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
3220         if (err)
3221                 return err;
3222
3223         /* connecting socket */
3224         ssec = sock->sk->sk_security;
3225         ssec->peer_sid = other_isec->sid;
3226         
3227         /* server child socket */
3228         ssec = newsk->sk_security;
3229         ssec->peer_sid = isec->sid;
3230         
3231         return 0;
3232 }
3233
3234 static int selinux_socket_unix_may_send(struct socket *sock,
3235                                         struct socket *other)
3236 {
3237         struct inode_security_struct *isec;
3238         struct inode_security_struct *other_isec;
3239         struct avc_audit_data ad;
3240         int err;
3241
3242         isec = SOCK_INODE(sock)->i_security;
3243         other_isec = SOCK_INODE(other)->i_security;
3244
3245         AVC_AUDIT_DATA_INIT(&ad,NET);
3246         ad.u.net.sk = other->sk;
3247
3248         err = avc_has_perm(isec->sid, other_isec->sid,
3249                            isec->sclass, SOCKET__SENDTO, &ad);
3250         if (err)
3251                 return err;
3252
3253         return 0;
3254 }
3255
3256 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3257 {
3258         u16 family;
3259         char *addrp;
3260         int len, err = 0;
3261         u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
3262         u32 sock_sid = 0;
3263         u16 sock_class = 0;
3264         struct socket *sock;
3265         struct net_device *dev;
3266         struct avc_audit_data ad;
3267
3268         family = sk->sk_family;
3269         if (family != PF_INET && family != PF_INET6)
3270                 goto out;
3271
3272         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
3273         if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP))
3274                 family = PF_INET;
3275
3276         read_lock_bh(&sk->sk_callback_lock);
3277         sock = sk->sk_socket;
3278         if (sock) {
3279                 struct inode *inode;
3280                 inode = SOCK_INODE(sock);
3281                 if (inode) {
3282                         struct inode_security_struct *isec;
3283                         isec = inode->i_security;
3284                         sock_sid = isec->sid;
3285                         sock_class = isec->sclass;
3286                 }
3287         }
3288         read_unlock_bh(&sk->sk_callback_lock);
3289         if (!sock_sid)
3290                 goto out;
3291
3292         dev = skb->dev;
3293         if (!dev)
3294