Commit | Line | Data |
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1da177e4 LT |
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> | |
effad8df PM |
15 | * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. |
16 | * Paul Moore <paul.moore@hp.com> | |
788e7dd4 YN |
17 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
18 | * Yuichi Nakamura <ynakam@hitachisoft.jp> | |
1da177e4 LT |
19 | * |
20 | * This program is free software; you can redistribute it and/or modify | |
21 | * it under the terms of the GNU General Public License version 2, | |
22 | * as published by the Free Software Foundation. | |
23 | */ | |
24 | ||
1da177e4 LT |
25 | #include <linux/init.h> |
26 | #include <linux/kernel.h> | |
27 | #include <linux/ptrace.h> | |
28 | #include <linux/errno.h> | |
29 | #include <linux/sched.h> | |
30 | #include <linux/security.h> | |
31 | #include <linux/xattr.h> | |
32 | #include <linux/capability.h> | |
33 | #include <linux/unistd.h> | |
34 | #include <linux/mm.h> | |
35 | #include <linux/mman.h> | |
36 | #include <linux/slab.h> | |
37 | #include <linux/pagemap.h> | |
38 | #include <linux/swap.h> | |
1da177e4 LT |
39 | #include <linux/spinlock.h> |
40 | #include <linux/syscalls.h> | |
41 | #include <linux/file.h> | |
42 | #include <linux/namei.h> | |
43 | #include <linux/mount.h> | |
44 | #include <linux/ext2_fs.h> | |
45 | #include <linux/proc_fs.h> | |
46 | #include <linux/kd.h> | |
47 | #include <linux/netfilter_ipv4.h> | |
48 | #include <linux/netfilter_ipv6.h> | |
49 | #include <linux/tty.h> | |
50 | #include <net/icmp.h> | |
227b60f5 | 51 | #include <net/ip.h> /* for local_port_range[] */ |
1da177e4 | 52 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ |
220deb96 | 53 | #include <net/net_namespace.h> |
d621d35e | 54 | #include <net/netlabel.h> |
1da177e4 | 55 | #include <asm/uaccess.h> |
1da177e4 | 56 | #include <asm/ioctls.h> |
d621d35e | 57 | #include <asm/atomic.h> |
1da177e4 LT |
58 | #include <linux/bitops.h> |
59 | #include <linux/interrupt.h> | |
60 | #include <linux/netdevice.h> /* for network interface checks */ | |
61 | #include <linux/netlink.h> | |
62 | #include <linux/tcp.h> | |
63 | #include <linux/udp.h> | |
2ee92d46 | 64 | #include <linux/dccp.h> |
1da177e4 LT |
65 | #include <linux/quota.h> |
66 | #include <linux/un.h> /* for Unix socket types */ | |
67 | #include <net/af_unix.h> /* for Unix socket types */ | |
68 | #include <linux/parser.h> | |
69 | #include <linux/nfs_mount.h> | |
70 | #include <net/ipv6.h> | |
71 | #include <linux/hugetlb.h> | |
72 | #include <linux/personality.h> | |
73 | #include <linux/sysctl.h> | |
74 | #include <linux/audit.h> | |
6931dfc9 | 75 | #include <linux/string.h> |
877ce7c1 | 76 | #include <linux/selinux.h> |
23970741 | 77 | #include <linux/mutex.h> |
1da177e4 LT |
78 | |
79 | #include "avc.h" | |
80 | #include "objsec.h" | |
81 | #include "netif.h" | |
224dfbd8 | 82 | #include "netnode.h" |
d28d1e08 | 83 | #include "xfrm.h" |
c60475bf | 84 | #include "netlabel.h" |
1da177e4 LT |
85 | |
86 | #define XATTR_SELINUX_SUFFIX "selinux" | |
87 | #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX | |
88 | ||
c9180a57 EP |
89 | #define NUM_SEL_MNT_OPTS 4 |
90 | ||
1da177e4 LT |
91 | extern unsigned int policydb_loaded_version; |
92 | extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); | |
4e5ab4cb | 93 | extern int selinux_compat_net; |
20510f2f | 94 | extern struct security_operations *security_ops; |
1da177e4 | 95 | |
d621d35e PM |
96 | /* SECMARK reference count */ |
97 | atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); | |
98 | ||
1da177e4 LT |
99 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
100 | int selinux_enforcing = 0; | |
101 | ||
102 | static int __init enforcing_setup(char *str) | |
103 | { | |
104 | selinux_enforcing = simple_strtol(str,NULL,0); | |
105 | return 1; | |
106 | } | |
107 | __setup("enforcing=", enforcing_setup); | |
108 | #endif | |
109 | ||
110 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
111 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
112 | ||
113 | static int __init selinux_enabled_setup(char *str) | |
114 | { | |
115 | selinux_enabled = simple_strtol(str, NULL, 0); | |
116 | return 1; | |
117 | } | |
118 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
119 | #else |
120 | int selinux_enabled = 1; | |
1da177e4 LT |
121 | #endif |
122 | ||
123 | /* Original (dummy) security module. */ | |
124 | static struct security_operations *original_ops = NULL; | |
125 | ||
126 | /* Minimal support for a secondary security module, | |
127 | just to allow the use of the dummy or capability modules. | |
128 | The owlsm module can alternatively be used as a secondary | |
129 | module as long as CONFIG_OWLSM_FD is not enabled. */ | |
130 | static struct security_operations *secondary_ops = NULL; | |
131 | ||
132 | /* Lists of inode and superblock security structures initialized | |
133 | before the policy was loaded. */ | |
134 | static LIST_HEAD(superblock_security_head); | |
135 | static DEFINE_SPINLOCK(sb_security_lock); | |
136 | ||
e18b890b | 137 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 138 | |
d621d35e PM |
139 | /** |
140 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
141 | * | |
142 | * Description: | |
143 | * This function checks the SECMARK reference counter to see if any SECMARK | |
144 | * targets are currently configured, if the reference counter is greater than | |
145 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
146 | * enabled, false (0) if SECMARK is disabled. | |
147 | * | |
148 | */ | |
149 | static int selinux_secmark_enabled(void) | |
150 | { | |
151 | return (atomic_read(&selinux_secmark_refcount) > 0); | |
152 | } | |
153 | ||
1da177e4 LT |
154 | /* Allocate and free functions for each kind of security blob. */ |
155 | ||
156 | static int task_alloc_security(struct task_struct *task) | |
157 | { | |
158 | struct task_security_struct *tsec; | |
159 | ||
89d155ef | 160 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 LT |
161 | if (!tsec) |
162 | return -ENOMEM; | |
163 | ||
1da177e4 LT |
164 | tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; |
165 | task->security = tsec; | |
166 | ||
167 | return 0; | |
168 | } | |
169 | ||
170 | static void task_free_security(struct task_struct *task) | |
171 | { | |
172 | struct task_security_struct *tsec = task->security; | |
1da177e4 LT |
173 | task->security = NULL; |
174 | kfree(tsec); | |
175 | } | |
176 | ||
177 | static int inode_alloc_security(struct inode *inode) | |
178 | { | |
179 | struct task_security_struct *tsec = current->security; | |
180 | struct inode_security_struct *isec; | |
181 | ||
a02fe132 | 182 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
183 | if (!isec) |
184 | return -ENOMEM; | |
185 | ||
23970741 | 186 | mutex_init(&isec->lock); |
1da177e4 | 187 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
188 | isec->inode = inode; |
189 | isec->sid = SECINITSID_UNLABELED; | |
190 | isec->sclass = SECCLASS_FILE; | |
9ac49d22 | 191 | isec->task_sid = tsec->sid; |
1da177e4 LT |
192 | inode->i_security = isec; |
193 | ||
194 | return 0; | |
195 | } | |
196 | ||
197 | static void inode_free_security(struct inode *inode) | |
198 | { | |
199 | struct inode_security_struct *isec = inode->i_security; | |
200 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
201 | ||
1da177e4 LT |
202 | spin_lock(&sbsec->isec_lock); |
203 | if (!list_empty(&isec->list)) | |
204 | list_del_init(&isec->list); | |
205 | spin_unlock(&sbsec->isec_lock); | |
206 | ||
207 | inode->i_security = NULL; | |
7cae7e26 | 208 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
209 | } |
210 | ||
211 | static int file_alloc_security(struct file *file) | |
212 | { | |
213 | struct task_security_struct *tsec = current->security; | |
214 | struct file_security_struct *fsec; | |
215 | ||
26d2a4be | 216 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
217 | if (!fsec) |
218 | return -ENOMEM; | |
219 | ||
9ac49d22 SS |
220 | fsec->sid = tsec->sid; |
221 | fsec->fown_sid = tsec->sid; | |
1da177e4 LT |
222 | file->f_security = fsec; |
223 | ||
224 | return 0; | |
225 | } | |
226 | ||
227 | static void file_free_security(struct file *file) | |
228 | { | |
229 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
230 | file->f_security = NULL; |
231 | kfree(fsec); | |
232 | } | |
233 | ||
234 | static int superblock_alloc_security(struct super_block *sb) | |
235 | { | |
236 | struct superblock_security_struct *sbsec; | |
237 | ||
89d155ef | 238 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
239 | if (!sbsec) |
240 | return -ENOMEM; | |
241 | ||
bc7e982b | 242 | mutex_init(&sbsec->lock); |
1da177e4 LT |
243 | INIT_LIST_HEAD(&sbsec->list); |
244 | INIT_LIST_HEAD(&sbsec->isec_head); | |
245 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
246 | sbsec->sb = sb; |
247 | sbsec->sid = SECINITSID_UNLABELED; | |
248 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 249 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
250 | sb->s_security = sbsec; |
251 | ||
252 | return 0; | |
253 | } | |
254 | ||
255 | static void superblock_free_security(struct super_block *sb) | |
256 | { | |
257 | struct superblock_security_struct *sbsec = sb->s_security; | |
258 | ||
1da177e4 LT |
259 | spin_lock(&sb_security_lock); |
260 | if (!list_empty(&sbsec->list)) | |
261 | list_del_init(&sbsec->list); | |
262 | spin_unlock(&sb_security_lock); | |
263 | ||
264 | sb->s_security = NULL; | |
265 | kfree(sbsec); | |
266 | } | |
267 | ||
7d877f3b | 268 | static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
1da177e4 LT |
269 | { |
270 | struct sk_security_struct *ssec; | |
271 | ||
89d155ef | 272 | ssec = kzalloc(sizeof(*ssec), priority); |
1da177e4 LT |
273 | if (!ssec) |
274 | return -ENOMEM; | |
275 | ||
1da177e4 | 276 | ssec->peer_sid = SECINITSID_UNLABELED; |
892c141e | 277 | ssec->sid = SECINITSID_UNLABELED; |
1da177e4 LT |
278 | sk->sk_security = ssec; |
279 | ||
f74af6e8 | 280 | selinux_netlbl_sk_security_reset(ssec, family); |
99f59ed0 | 281 | |
1da177e4 LT |
282 | return 0; |
283 | } | |
284 | ||
285 | static void sk_free_security(struct sock *sk) | |
286 | { | |
287 | struct sk_security_struct *ssec = sk->sk_security; | |
288 | ||
1da177e4 LT |
289 | sk->sk_security = NULL; |
290 | kfree(ssec); | |
291 | } | |
1da177e4 LT |
292 | |
293 | /* The security server must be initialized before | |
294 | any labeling or access decisions can be provided. */ | |
295 | extern int ss_initialized; | |
296 | ||
297 | /* The file system's label must be initialized prior to use. */ | |
298 | ||
299 | static char *labeling_behaviors[6] = { | |
300 | "uses xattr", | |
301 | "uses transition SIDs", | |
302 | "uses task SIDs", | |
303 | "uses genfs_contexts", | |
304 | "not configured for labeling", | |
305 | "uses mountpoint labeling", | |
306 | }; | |
307 | ||
308 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
309 | ||
310 | static inline int inode_doinit(struct inode *inode) | |
311 | { | |
312 | return inode_doinit_with_dentry(inode, NULL); | |
313 | } | |
314 | ||
315 | enum { | |
31e87930 | 316 | Opt_error = -1, |
1da177e4 LT |
317 | Opt_context = 1, |
318 | Opt_fscontext = 2, | |
c9180a57 EP |
319 | Opt_defcontext = 3, |
320 | Opt_rootcontext = 4, | |
1da177e4 LT |
321 | }; |
322 | ||
323 | static match_table_t tokens = { | |
324 | {Opt_context, "context=%s"}, | |
325 | {Opt_fscontext, "fscontext=%s"}, | |
326 | {Opt_defcontext, "defcontext=%s"}, | |
0808925e | 327 | {Opt_rootcontext, "rootcontext=%s"}, |
31e87930 | 328 | {Opt_error, NULL}, |
1da177e4 LT |
329 | }; |
330 | ||
331 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
332 | ||
c312feb2 EP |
333 | static int may_context_mount_sb_relabel(u32 sid, |
334 | struct superblock_security_struct *sbsec, | |
335 | struct task_security_struct *tsec) | |
336 | { | |
337 | int rc; | |
338 | ||
339 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
340 | FILESYSTEM__RELABELFROM, NULL); | |
341 | if (rc) | |
342 | return rc; | |
343 | ||
344 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
345 | FILESYSTEM__RELABELTO, NULL); | |
346 | return rc; | |
347 | } | |
348 | ||
0808925e EP |
349 | static int may_context_mount_inode_relabel(u32 sid, |
350 | struct superblock_security_struct *sbsec, | |
351 | struct task_security_struct *tsec) | |
352 | { | |
353 | int rc; | |
354 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
355 | FILESYSTEM__RELABELFROM, NULL); | |
356 | if (rc) | |
357 | return rc; | |
358 | ||
359 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
360 | FILESYSTEM__ASSOCIATE, NULL); | |
361 | return rc; | |
362 | } | |
363 | ||
c9180a57 | 364 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 365 | { |
1da177e4 | 366 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
367 | struct dentry *root = sb->s_root; |
368 | struct inode *root_inode = root->d_inode; | |
369 | int rc = 0; | |
1da177e4 | 370 | |
c9180a57 EP |
371 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
372 | /* Make sure that the xattr handler exists and that no | |
373 | error other than -ENODATA is returned by getxattr on | |
374 | the root directory. -ENODATA is ok, as this may be | |
375 | the first boot of the SELinux kernel before we have | |
376 | assigned xattr values to the filesystem. */ | |
377 | if (!root_inode->i_op->getxattr) { | |
378 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
379 | "xattr support\n", sb->s_id, sb->s_type->name); | |
380 | rc = -EOPNOTSUPP; | |
381 | goto out; | |
382 | } | |
383 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
384 | if (rc < 0 && rc != -ENODATA) { | |
385 | if (rc == -EOPNOTSUPP) | |
386 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
387 | "%s) has no security xattr handler\n", | |
388 | sb->s_id, sb->s_type->name); | |
389 | else | |
390 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
391 | "%s) getxattr errno %d\n", sb->s_id, | |
392 | sb->s_type->name, -rc); | |
393 | goto out; | |
394 | } | |
395 | } | |
1da177e4 | 396 | |
c9180a57 | 397 | sbsec->initialized = 1; |
1da177e4 | 398 | |
c9180a57 EP |
399 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
400 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
401 | sb->s_id, sb->s_type->name); | |
402 | else | |
403 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", | |
404 | sb->s_id, sb->s_type->name, | |
405 | labeling_behaviors[sbsec->behavior-1]); | |
1da177e4 | 406 | |
c9180a57 EP |
407 | /* Initialize the root inode. */ |
408 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 409 | |
c9180a57 EP |
410 | /* Initialize any other inodes associated with the superblock, e.g. |
411 | inodes created prior to initial policy load or inodes created | |
412 | during get_sb by a pseudo filesystem that directly | |
413 | populates itself. */ | |
414 | spin_lock(&sbsec->isec_lock); | |
415 | next_inode: | |
416 | if (!list_empty(&sbsec->isec_head)) { | |
417 | struct inode_security_struct *isec = | |
418 | list_entry(sbsec->isec_head.next, | |
419 | struct inode_security_struct, list); | |
420 | struct inode *inode = isec->inode; | |
421 | spin_unlock(&sbsec->isec_lock); | |
422 | inode = igrab(inode); | |
423 | if (inode) { | |
424 | if (!IS_PRIVATE(inode)) | |
425 | inode_doinit(inode); | |
426 | iput(inode); | |
427 | } | |
428 | spin_lock(&sbsec->isec_lock); | |
429 | list_del_init(&isec->list); | |
430 | goto next_inode; | |
431 | } | |
432 | spin_unlock(&sbsec->isec_lock); | |
433 | out: | |
434 | return rc; | |
435 | } | |
1da177e4 | 436 | |
c9180a57 EP |
437 | /* |
438 | * This function should allow an FS to ask what it's mount security | |
439 | * options were so it can use those later for submounts, displaying | |
440 | * mount options, or whatever. | |
441 | */ | |
442 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 443 | struct security_mnt_opts *opts) |
c9180a57 EP |
444 | { |
445 | int rc = 0, i; | |
446 | struct superblock_security_struct *sbsec = sb->s_security; | |
447 | char *context = NULL; | |
448 | u32 len; | |
449 | char tmp; | |
1da177e4 | 450 | |
e0007529 | 451 | security_init_mnt_opts(opts); |
1da177e4 | 452 | |
c9180a57 EP |
453 | if (!sbsec->initialized) |
454 | return -EINVAL; | |
1da177e4 | 455 | |
c9180a57 EP |
456 | if (!ss_initialized) |
457 | return -EINVAL; | |
1da177e4 | 458 | |
c9180a57 EP |
459 | /* |
460 | * if we ever use sbsec flags for anything other than tracking mount | |
461 | * settings this is going to need a mask | |
462 | */ | |
463 | tmp = sbsec->flags; | |
464 | /* count the number of mount options for this sb */ | |
465 | for (i = 0; i < 8; i++) { | |
466 | if (tmp & 0x01) | |
e0007529 | 467 | opts->num_mnt_opts++; |
c9180a57 EP |
468 | tmp >>= 1; |
469 | } | |
1da177e4 | 470 | |
e0007529 EP |
471 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
472 | if (!opts->mnt_opts) { | |
c9180a57 EP |
473 | rc = -ENOMEM; |
474 | goto out_free; | |
475 | } | |
1da177e4 | 476 | |
e0007529 EP |
477 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
478 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
479 | rc = -ENOMEM; |
480 | goto out_free; | |
481 | } | |
1da177e4 | 482 | |
c9180a57 EP |
483 | i = 0; |
484 | if (sbsec->flags & FSCONTEXT_MNT) { | |
485 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
486 | if (rc) | |
487 | goto out_free; | |
e0007529 EP |
488 | opts->mnt_opts[i] = context; |
489 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
490 | } |
491 | if (sbsec->flags & CONTEXT_MNT) { | |
492 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
493 | if (rc) | |
494 | goto out_free; | |
e0007529 EP |
495 | opts->mnt_opts[i] = context; |
496 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
497 | } |
498 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
499 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
500 | if (rc) | |
501 | goto out_free; | |
e0007529 EP |
502 | opts->mnt_opts[i] = context; |
503 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
504 | } |
505 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
506 | struct inode *root = sbsec->sb->s_root->d_inode; | |
507 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 508 | |
c9180a57 EP |
509 | rc = security_sid_to_context(isec->sid, &context, &len); |
510 | if (rc) | |
511 | goto out_free; | |
e0007529 EP |
512 | opts->mnt_opts[i] = context; |
513 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 514 | } |
1da177e4 | 515 | |
e0007529 | 516 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 517 | |
c9180a57 EP |
518 | return 0; |
519 | ||
520 | out_free: | |
e0007529 | 521 | security_free_mnt_opts(opts); |
c9180a57 EP |
522 | return rc; |
523 | } | |
1da177e4 | 524 | |
c9180a57 EP |
525 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
526 | u32 old_sid, u32 new_sid) | |
527 | { | |
528 | /* check if the old mount command had the same options */ | |
529 | if (sbsec->initialized) | |
530 | if (!(sbsec->flags & flag) || | |
531 | (old_sid != new_sid)) | |
532 | return 1; | |
533 | ||
534 | /* check if we were passed the same options twice, | |
535 | * aka someone passed context=a,context=b | |
536 | */ | |
537 | if (!sbsec->initialized) | |
538 | if (sbsec->flags & flag) | |
539 | return 1; | |
540 | return 0; | |
541 | } | |
e0007529 | 542 | |
c9180a57 EP |
543 | /* |
544 | * Allow filesystems with binary mount data to explicitly set mount point | |
545 | * labeling information. | |
546 | */ | |
e0007529 EP |
547 | static int selinux_set_mnt_opts(struct super_block *sb, |
548 | struct security_mnt_opts *opts) | |
c9180a57 EP |
549 | { |
550 | int rc = 0, i; | |
551 | struct task_security_struct *tsec = current->security; | |
552 | struct superblock_security_struct *sbsec = sb->s_security; | |
553 | const char *name = sb->s_type->name; | |
554 | struct inode *inode = sbsec->sb->s_root->d_inode; | |
555 | struct inode_security_struct *root_isec = inode->i_security; | |
556 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; | |
557 | u32 defcontext_sid = 0; | |
e0007529 EP |
558 | char **mount_options = opts->mnt_opts; |
559 | int *flags = opts->mnt_opts_flags; | |
560 | int num_opts = opts->num_mnt_opts; | |
c9180a57 EP |
561 | |
562 | mutex_lock(&sbsec->lock); | |
563 | ||
564 | if (!ss_initialized) { | |
565 | if (!num_opts) { | |
566 | /* Defer initialization until selinux_complete_init, | |
567 | after the initial policy is loaded and the security | |
568 | server is ready to handle calls. */ | |
569 | spin_lock(&sb_security_lock); | |
570 | if (list_empty(&sbsec->list)) | |
571 | list_add(&sbsec->list, &superblock_security_head); | |
572 | spin_unlock(&sb_security_lock); | |
573 | goto out; | |
574 | } | |
575 | rc = -EINVAL; | |
576 | printk(KERN_WARNING "Unable to set superblock options before " | |
577 | "the security server is initialized\n"); | |
1da177e4 | 578 | goto out; |
c9180a57 | 579 | } |
1da177e4 | 580 | |
e0007529 EP |
581 | /* |
582 | * Binary mount data FS will come through this function twice. Once | |
583 | * from an explicit call and once from the generic calls from the vfs. | |
584 | * Since the generic VFS calls will not contain any security mount data | |
585 | * we need to skip the double mount verification. | |
586 | * | |
587 | * This does open a hole in which we will not notice if the first | |
588 | * mount using this sb set explict options and a second mount using | |
589 | * this sb does not set any security options. (The first options | |
590 | * will be used for both mounts) | |
591 | */ | |
592 | if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
593 | && (num_opts == 0)) | |
594 | goto out; | |
595 | ||
c9180a57 EP |
596 | /* |
597 | * parse the mount options, check if they are valid sids. | |
598 | * also check if someone is trying to mount the same sb more | |
599 | * than once with different security options. | |
600 | */ | |
601 | for (i = 0; i < num_opts; i++) { | |
602 | u32 sid; | |
603 | rc = security_context_to_sid(mount_options[i], | |
604 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
605 | if (rc) { |
606 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
607 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
c9180a57 EP |
608 | mount_options[i], sb->s_id, name, rc); |
609 | goto out; | |
610 | } | |
611 | switch (flags[i]) { | |
612 | case FSCONTEXT_MNT: | |
613 | fscontext_sid = sid; | |
614 | ||
615 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
616 | fscontext_sid)) | |
617 | goto out_double_mount; | |
618 | ||
619 | sbsec->flags |= FSCONTEXT_MNT; | |
620 | break; | |
621 | case CONTEXT_MNT: | |
622 | context_sid = sid; | |
623 | ||
624 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
625 | context_sid)) | |
626 | goto out_double_mount; | |
627 | ||
628 | sbsec->flags |= CONTEXT_MNT; | |
629 | break; | |
630 | case ROOTCONTEXT_MNT: | |
631 | rootcontext_sid = sid; | |
632 | ||
633 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
634 | rootcontext_sid)) | |
635 | goto out_double_mount; | |
636 | ||
637 | sbsec->flags |= ROOTCONTEXT_MNT; | |
638 | ||
639 | break; | |
640 | case DEFCONTEXT_MNT: | |
641 | defcontext_sid = sid; | |
642 | ||
643 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
644 | defcontext_sid)) | |
645 | goto out_double_mount; | |
646 | ||
647 | sbsec->flags |= DEFCONTEXT_MNT; | |
648 | ||
649 | break; | |
650 | default: | |
651 | rc = -EINVAL; | |
652 | goto out; | |
1da177e4 | 653 | } |
c9180a57 EP |
654 | } |
655 | ||
656 | if (sbsec->initialized) { | |
657 | /* previously mounted with options, but not on this attempt? */ | |
658 | if (sbsec->flags && !num_opts) | |
659 | goto out_double_mount; | |
660 | rc = 0; | |
661 | goto out; | |
662 | } | |
663 | ||
664 | if (strcmp(sb->s_type->name, "proc") == 0) | |
665 | sbsec->proc = 1; | |
666 | ||
667 | /* Determine the labeling behavior to use for this filesystem type. */ | |
668 | rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); | |
669 | if (rc) { | |
670 | printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", | |
671 | __FUNCTION__, sb->s_type->name, rc); | |
672 | goto out; | |
673 | } | |
1da177e4 | 674 | |
c9180a57 EP |
675 | /* sets the context of the superblock for the fs being mounted. */ |
676 | if (fscontext_sid) { | |
677 | ||
678 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec); | |
1da177e4 | 679 | if (rc) |
c9180a57 | 680 | goto out; |
1da177e4 | 681 | |
c9180a57 | 682 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
683 | } |
684 | ||
685 | /* | |
686 | * Switch to using mount point labeling behavior. | |
687 | * sets the label used on all file below the mountpoint, and will set | |
688 | * the superblock context if not already set. | |
689 | */ | |
c9180a57 EP |
690 | if (context_sid) { |
691 | if (!fscontext_sid) { | |
692 | rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec); | |
b04ea3ce | 693 | if (rc) |
c9180a57 EP |
694 | goto out; |
695 | sbsec->sid = context_sid; | |
b04ea3ce | 696 | } else { |
c9180a57 | 697 | rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec); |
b04ea3ce | 698 | if (rc) |
c9180a57 | 699 | goto out; |
b04ea3ce | 700 | } |
c9180a57 EP |
701 | if (!rootcontext_sid) |
702 | rootcontext_sid = context_sid; | |
1da177e4 | 703 | |
c9180a57 | 704 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 705 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
706 | } |
707 | ||
c9180a57 EP |
708 | if (rootcontext_sid) { |
709 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec); | |
0808925e | 710 | if (rc) |
c9180a57 | 711 | goto out; |
0808925e | 712 | |
c9180a57 EP |
713 | root_isec->sid = rootcontext_sid; |
714 | root_isec->initialized = 1; | |
0808925e EP |
715 | } |
716 | ||
c9180a57 EP |
717 | if (defcontext_sid) { |
718 | if (sbsec->behavior != SECURITY_FS_USE_XATTR) { | |
719 | rc = -EINVAL; | |
720 | printk(KERN_WARNING "SELinux: defcontext option is " | |
721 | "invalid for this filesystem type\n"); | |
722 | goto out; | |
1da177e4 LT |
723 | } |
724 | ||
c9180a57 EP |
725 | if (defcontext_sid != sbsec->def_sid) { |
726 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
727 | sbsec, tsec); | |
728 | if (rc) | |
729 | goto out; | |
730 | } | |
1da177e4 | 731 | |
c9180a57 | 732 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
733 | } |
734 | ||
c9180a57 | 735 | rc = sb_finish_set_opts(sb); |
1da177e4 | 736 | out: |
c9180a57 | 737 | mutex_unlock(&sbsec->lock); |
1da177e4 | 738 | return rc; |
c9180a57 EP |
739 | out_double_mount: |
740 | rc = -EINVAL; | |
741 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
742 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
743 | goto out; | |
1da177e4 LT |
744 | } |
745 | ||
c9180a57 EP |
746 | static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
747 | struct super_block *newsb) | |
1da177e4 | 748 | { |
c9180a57 EP |
749 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
750 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 751 | |
c9180a57 EP |
752 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
753 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
754 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 755 | |
c9180a57 EP |
756 | /* we can't error, we can't save the info, this shouldn't get called |
757 | * this early in the boot process. */ | |
758 | BUG_ON(!ss_initialized); | |
759 | ||
c9180a57 EP |
760 | /* how can we clone if the old one wasn't set up?? */ |
761 | BUG_ON(!oldsbsec->initialized); | |
762 | ||
5a552617 EP |
763 | /* if fs is reusing a sb, just let its options stand... */ |
764 | if (newsbsec->initialized) | |
765 | return; | |
766 | ||
c9180a57 EP |
767 | mutex_lock(&newsbsec->lock); |
768 | ||
769 | newsbsec->flags = oldsbsec->flags; | |
770 | ||
771 | newsbsec->sid = oldsbsec->sid; | |
772 | newsbsec->def_sid = oldsbsec->def_sid; | |
773 | newsbsec->behavior = oldsbsec->behavior; | |
774 | ||
775 | if (set_context) { | |
776 | u32 sid = oldsbsec->mntpoint_sid; | |
777 | ||
778 | if (!set_fscontext) | |
779 | newsbsec->sid = sid; | |
780 | if (!set_rootcontext) { | |
781 | struct inode *newinode = newsb->s_root->d_inode; | |
782 | struct inode_security_struct *newisec = newinode->i_security; | |
783 | newisec->sid = sid; | |
784 | } | |
785 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 786 | } |
c9180a57 EP |
787 | if (set_rootcontext) { |
788 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
789 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
790 | struct inode *newinode = newsb->s_root->d_inode; | |
791 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 792 | |
c9180a57 | 793 | newisec->sid = oldisec->sid; |
1da177e4 LT |
794 | } |
795 | ||
c9180a57 EP |
796 | sb_finish_set_opts(newsb); |
797 | mutex_unlock(&newsbsec->lock); | |
798 | } | |
799 | ||
2e1479d9 AB |
800 | static int selinux_parse_opts_str(char *options, |
801 | struct security_mnt_opts *opts) | |
c9180a57 | 802 | { |
e0007529 | 803 | char *p; |
c9180a57 EP |
804 | char *context = NULL, *defcontext = NULL; |
805 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 806 | int rc, num_mnt_opts = 0; |
1da177e4 | 807 | |
e0007529 | 808 | opts->num_mnt_opts = 0; |
1da177e4 | 809 | |
c9180a57 EP |
810 | /* Standard string-based options. */ |
811 | while ((p = strsep(&options, "|")) != NULL) { | |
812 | int token; | |
813 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 814 | |
c9180a57 EP |
815 | if (!*p) |
816 | continue; | |
1da177e4 | 817 | |
c9180a57 | 818 | token = match_token(p, tokens, args); |
1da177e4 | 819 | |
c9180a57 EP |
820 | switch (token) { |
821 | case Opt_context: | |
822 | if (context || defcontext) { | |
823 | rc = -EINVAL; | |
824 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
825 | goto out_err; | |
826 | } | |
827 | context = match_strdup(&args[0]); | |
828 | if (!context) { | |
829 | rc = -ENOMEM; | |
830 | goto out_err; | |
831 | } | |
832 | break; | |
833 | ||
834 | case Opt_fscontext: | |
835 | if (fscontext) { | |
836 | rc = -EINVAL; | |
837 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
838 | goto out_err; | |
839 | } | |
840 | fscontext = match_strdup(&args[0]); | |
841 | if (!fscontext) { | |
842 | rc = -ENOMEM; | |
843 | goto out_err; | |
844 | } | |
845 | break; | |
846 | ||
847 | case Opt_rootcontext: | |
848 | if (rootcontext) { | |
849 | rc = -EINVAL; | |
850 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
851 | goto out_err; | |
852 | } | |
853 | rootcontext = match_strdup(&args[0]); | |
854 | if (!rootcontext) { | |
855 | rc = -ENOMEM; | |
856 | goto out_err; | |
857 | } | |
858 | break; | |
859 | ||
860 | case Opt_defcontext: | |
861 | if (context || defcontext) { | |
862 | rc = -EINVAL; | |
863 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
864 | goto out_err; | |
865 | } | |
866 | defcontext = match_strdup(&args[0]); | |
867 | if (!defcontext) { | |
868 | rc = -ENOMEM; | |
869 | goto out_err; | |
870 | } | |
871 | break; | |
872 | ||
873 | default: | |
874 | rc = -EINVAL; | |
875 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
876 | goto out_err; | |
1da177e4 | 877 | |
1da177e4 | 878 | } |
1da177e4 | 879 | } |
c9180a57 | 880 | |
e0007529 EP |
881 | rc = -ENOMEM; |
882 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
883 | if (!opts->mnt_opts) | |
884 | goto out_err; | |
885 | ||
886 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
887 | if (!opts->mnt_opts_flags) { | |
888 | kfree(opts->mnt_opts); | |
889 | goto out_err; | |
890 | } | |
891 | ||
c9180a57 | 892 | if (fscontext) { |
e0007529 EP |
893 | opts->mnt_opts[num_mnt_opts] = fscontext; |
894 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
895 | } |
896 | if (context) { | |
e0007529 EP |
897 | opts->mnt_opts[num_mnt_opts] = context; |
898 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
899 | } |
900 | if (rootcontext) { | |
e0007529 EP |
901 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
902 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
903 | } |
904 | if (defcontext) { | |
e0007529 EP |
905 | opts->mnt_opts[num_mnt_opts] = defcontext; |
906 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
907 | } |
908 | ||
e0007529 EP |
909 | opts->num_mnt_opts = num_mnt_opts; |
910 | return 0; | |
911 | ||
c9180a57 EP |
912 | out_err: |
913 | kfree(context); | |
914 | kfree(defcontext); | |
915 | kfree(fscontext); | |
916 | kfree(rootcontext); | |
1da177e4 LT |
917 | return rc; |
918 | } | |
e0007529 EP |
919 | /* |
920 | * string mount options parsing and call set the sbsec | |
921 | */ | |
922 | static int superblock_doinit(struct super_block *sb, void *data) | |
923 | { | |
924 | int rc = 0; | |
925 | char *options = data; | |
926 | struct security_mnt_opts opts; | |
927 | ||
928 | security_init_mnt_opts(&opts); | |
929 | ||
930 | if (!data) | |
931 | goto out; | |
932 | ||
933 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
934 | ||
935 | rc = selinux_parse_opts_str(options, &opts); | |
936 | if (rc) | |
937 | goto out_err; | |
938 | ||
939 | out: | |
940 | rc = selinux_set_mnt_opts(sb, &opts); | |
941 | ||
942 | out_err: | |
943 | security_free_mnt_opts(&opts); | |
944 | return rc; | |
945 | } | |
1da177e4 LT |
946 | |
947 | static inline u16 inode_mode_to_security_class(umode_t mode) | |
948 | { | |
949 | switch (mode & S_IFMT) { | |
950 | case S_IFSOCK: | |
951 | return SECCLASS_SOCK_FILE; | |
952 | case S_IFLNK: | |
953 | return SECCLASS_LNK_FILE; | |
954 | case S_IFREG: | |
955 | return SECCLASS_FILE; | |
956 | case S_IFBLK: | |
957 | return SECCLASS_BLK_FILE; | |
958 | case S_IFDIR: | |
959 | return SECCLASS_DIR; | |
960 | case S_IFCHR: | |
961 | return SECCLASS_CHR_FILE; | |
962 | case S_IFIFO: | |
963 | return SECCLASS_FIFO_FILE; | |
964 | ||
965 | } | |
966 | ||
967 | return SECCLASS_FILE; | |
968 | } | |
969 | ||
13402580 JM |
970 | static inline int default_protocol_stream(int protocol) |
971 | { | |
972 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
973 | } | |
974 | ||
975 | static inline int default_protocol_dgram(int protocol) | |
976 | { | |
977 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
978 | } | |
979 | ||
1da177e4 LT |
980 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
981 | { | |
982 | switch (family) { | |
983 | case PF_UNIX: | |
984 | switch (type) { | |
985 | case SOCK_STREAM: | |
986 | case SOCK_SEQPACKET: | |
987 | return SECCLASS_UNIX_STREAM_SOCKET; | |
988 | case SOCK_DGRAM: | |
989 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
990 | } | |
991 | break; | |
992 | case PF_INET: | |
993 | case PF_INET6: | |
994 | switch (type) { | |
995 | case SOCK_STREAM: | |
13402580 JM |
996 | if (default_protocol_stream(protocol)) |
997 | return SECCLASS_TCP_SOCKET; | |
998 | else | |
999 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1000 | case SOCK_DGRAM: |
13402580 JM |
1001 | if (default_protocol_dgram(protocol)) |
1002 | return SECCLASS_UDP_SOCKET; | |
1003 | else | |
1004 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1005 | case SOCK_DCCP: |
1006 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1007 | default: |
1da177e4 LT |
1008 | return SECCLASS_RAWIP_SOCKET; |
1009 | } | |
1010 | break; | |
1011 | case PF_NETLINK: | |
1012 | switch (protocol) { | |
1013 | case NETLINK_ROUTE: | |
1014 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1015 | case NETLINK_FIREWALL: | |
1016 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
216efaaa | 1017 | case NETLINK_INET_DIAG: |
1da177e4 LT |
1018 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1019 | case NETLINK_NFLOG: | |
1020 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1021 | case NETLINK_XFRM: | |
1022 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1023 | case NETLINK_SELINUX: | |
1024 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1025 | case NETLINK_AUDIT: | |
1026 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1027 | case NETLINK_IP6_FW: | |
1028 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1029 | case NETLINK_DNRTMSG: | |
1030 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1031 | case NETLINK_KOBJECT_UEVENT: |
1032 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1033 | default: |
1034 | return SECCLASS_NETLINK_SOCKET; | |
1035 | } | |
1036 | case PF_PACKET: | |
1037 | return SECCLASS_PACKET_SOCKET; | |
1038 | case PF_KEY: | |
1039 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1040 | case PF_APPLETALK: |
1041 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1042 | } |
1043 | ||
1044 | return SECCLASS_SOCKET; | |
1045 | } | |
1046 | ||
1047 | #ifdef CONFIG_PROC_FS | |
1048 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1049 | u16 tclass, | |
1050 | u32 *sid) | |
1051 | { | |
1052 | int buflen, rc; | |
1053 | char *buffer, *path, *end; | |
1054 | ||
1055 | buffer = (char*)__get_free_page(GFP_KERNEL); | |
1056 | if (!buffer) | |
1057 | return -ENOMEM; | |
1058 | ||
1059 | buflen = PAGE_SIZE; | |
1060 | end = buffer+buflen; | |
1061 | *--end = '\0'; | |
1062 | buflen--; | |
1063 | path = end-1; | |
1064 | *path = '/'; | |
1065 | while (de && de != de->parent) { | |
1066 | buflen -= de->namelen + 1; | |
1067 | if (buflen < 0) | |
1068 | break; | |
1069 | end -= de->namelen; | |
1070 | memcpy(end, de->name, de->namelen); | |
1071 | *--end = '/'; | |
1072 | path = end; | |
1073 | de = de->parent; | |
1074 | } | |
1075 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1076 | free_page((unsigned long)buffer); | |
1077 | return rc; | |
1078 | } | |
1079 | #else | |
1080 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1081 | u16 tclass, | |
1082 | u32 *sid) | |
1083 | { | |
1084 | return -EINVAL; | |
1085 | } | |
1086 | #endif | |
1087 | ||
1088 | /* The inode's security attributes must be initialized before first use. */ | |
1089 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1090 | { | |
1091 | struct superblock_security_struct *sbsec = NULL; | |
1092 | struct inode_security_struct *isec = inode->i_security; | |
1093 | u32 sid; | |
1094 | struct dentry *dentry; | |
1095 | #define INITCONTEXTLEN 255 | |
1096 | char *context = NULL; | |
1097 | unsigned len = 0; | |
1098 | int rc = 0; | |
1da177e4 LT |
1099 | |
1100 | if (isec->initialized) | |
1101 | goto out; | |
1102 | ||
23970741 | 1103 | mutex_lock(&isec->lock); |
1da177e4 | 1104 | if (isec->initialized) |
23970741 | 1105 | goto out_unlock; |
1da177e4 LT |
1106 | |
1107 | sbsec = inode->i_sb->s_security; | |
1108 | if (!sbsec->initialized) { | |
1109 | /* Defer initialization until selinux_complete_init, | |
1110 | after the initial policy is loaded and the security | |
1111 | server is ready to handle calls. */ | |
1112 | spin_lock(&sbsec->isec_lock); | |
1113 | if (list_empty(&isec->list)) | |
1114 | list_add(&isec->list, &sbsec->isec_head); | |
1115 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1116 | goto out_unlock; |
1da177e4 LT |
1117 | } |
1118 | ||
1119 | switch (sbsec->behavior) { | |
1120 | case SECURITY_FS_USE_XATTR: | |
1121 | if (!inode->i_op->getxattr) { | |
1122 | isec->sid = sbsec->def_sid; | |
1123 | break; | |
1124 | } | |
1125 | ||
1126 | /* Need a dentry, since the xattr API requires one. | |
1127 | Life would be simpler if we could just pass the inode. */ | |
1128 | if (opt_dentry) { | |
1129 | /* Called from d_instantiate or d_splice_alias. */ | |
1130 | dentry = dget(opt_dentry); | |
1131 | } else { | |
1132 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1133 | dentry = d_find_alias(inode); | |
1134 | } | |
1135 | if (!dentry) { | |
1136 | printk(KERN_WARNING "%s: no dentry for dev=%s " | |
1137 | "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, | |
1138 | inode->i_ino); | |
23970741 | 1139 | goto out_unlock; |
1da177e4 LT |
1140 | } |
1141 | ||
1142 | len = INITCONTEXTLEN; | |
869ab514 | 1143 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1144 | if (!context) { |
1145 | rc = -ENOMEM; | |
1146 | dput(dentry); | |
23970741 | 1147 | goto out_unlock; |
1da177e4 LT |
1148 | } |
1149 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1150 | context, len); | |
1151 | if (rc == -ERANGE) { | |
1152 | /* Need a larger buffer. Query for the right size. */ | |
1153 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1154 | NULL, 0); | |
1155 | if (rc < 0) { | |
1156 | dput(dentry); | |
23970741 | 1157 | goto out_unlock; |
1da177e4 LT |
1158 | } |
1159 | kfree(context); | |
1160 | len = rc; | |
869ab514 | 1161 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1162 | if (!context) { |
1163 | rc = -ENOMEM; | |
1164 | dput(dentry); | |
23970741 | 1165 | goto out_unlock; |
1da177e4 LT |
1166 | } |
1167 | rc = inode->i_op->getxattr(dentry, | |
1168 | XATTR_NAME_SELINUX, | |
1169 | context, len); | |
1170 | } | |
1171 | dput(dentry); | |
1172 | if (rc < 0) { | |
1173 | if (rc != -ENODATA) { | |
1174 | printk(KERN_WARNING "%s: getxattr returned " | |
1175 | "%d for dev=%s ino=%ld\n", __FUNCTION__, | |
1176 | -rc, inode->i_sb->s_id, inode->i_ino); | |
1177 | kfree(context); | |
23970741 | 1178 | goto out_unlock; |
1da177e4 LT |
1179 | } |
1180 | /* Map ENODATA to the default file SID */ | |
1181 | sid = sbsec->def_sid; | |
1182 | rc = 0; | |
1183 | } else { | |
f5c1d5b2 | 1184 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1185 | sbsec->def_sid, |
1186 | GFP_NOFS); | |
1da177e4 LT |
1187 | if (rc) { |
1188 | printk(KERN_WARNING "%s: context_to_sid(%s) " | |
1189 | "returned %d for dev=%s ino=%ld\n", | |
1190 | __FUNCTION__, context, -rc, | |
1191 | inode->i_sb->s_id, inode->i_ino); | |
1192 | kfree(context); | |
1193 | /* Leave with the unlabeled SID */ | |
1194 | rc = 0; | |
1195 | break; | |
1196 | } | |
1197 | } | |
1198 | kfree(context); | |
1199 | isec->sid = sid; | |
1200 | break; | |
1201 | case SECURITY_FS_USE_TASK: | |
1202 | isec->sid = isec->task_sid; | |
1203 | break; | |
1204 | case SECURITY_FS_USE_TRANS: | |
1205 | /* Default to the fs SID. */ | |
1206 | isec->sid = sbsec->sid; | |
1207 | ||
1208 | /* Try to obtain a transition SID. */ | |
1209 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1210 | rc = security_transition_sid(isec->task_sid, | |
1211 | sbsec->sid, | |
1212 | isec->sclass, | |
1213 | &sid); | |
1214 | if (rc) | |
23970741 | 1215 | goto out_unlock; |
1da177e4 LT |
1216 | isec->sid = sid; |
1217 | break; | |
c312feb2 EP |
1218 | case SECURITY_FS_USE_MNTPOINT: |
1219 | isec->sid = sbsec->mntpoint_sid; | |
1220 | break; | |
1da177e4 | 1221 | default: |
c312feb2 | 1222 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1223 | isec->sid = sbsec->sid; |
1224 | ||
1225 | if (sbsec->proc) { | |
1226 | struct proc_inode *proci = PROC_I(inode); | |
1227 | if (proci->pde) { | |
1228 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1229 | rc = selinux_proc_get_sid(proci->pde, | |
1230 | isec->sclass, | |
1231 | &sid); | |
1232 | if (rc) | |
23970741 | 1233 | goto out_unlock; |
1da177e4 LT |
1234 | isec->sid = sid; |
1235 | } | |
1236 | } | |
1237 | break; | |
1238 | } | |
1239 | ||
1240 | isec->initialized = 1; | |
1241 | ||
23970741 EP |
1242 | out_unlock: |
1243 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1244 | out: |
1245 | if (isec->sclass == SECCLASS_FILE) | |
1246 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1247 | return rc; |
1248 | } | |
1249 | ||
1250 | /* Convert a Linux signal to an access vector. */ | |
1251 | static inline u32 signal_to_av(int sig) | |
1252 | { | |
1253 | u32 perm = 0; | |
1254 | ||
1255 | switch (sig) { | |
1256 | case SIGCHLD: | |
1257 | /* Commonly granted from child to parent. */ | |
1258 | perm = PROCESS__SIGCHLD; | |
1259 | break; | |
1260 | case SIGKILL: | |
1261 | /* Cannot be caught or ignored */ | |
1262 | perm = PROCESS__SIGKILL; | |
1263 | break; | |
1264 | case SIGSTOP: | |
1265 | /* Cannot be caught or ignored */ | |
1266 | perm = PROCESS__SIGSTOP; | |
1267 | break; | |
1268 | default: | |
1269 | /* All other signals. */ | |
1270 | perm = PROCESS__SIGNAL; | |
1271 | break; | |
1272 | } | |
1273 | ||
1274 | return perm; | |
1275 | } | |
1276 | ||
1277 | /* Check permission betweeen a pair of tasks, e.g. signal checks, | |
1278 | fork check, ptrace check, etc. */ | |
1279 | static int task_has_perm(struct task_struct *tsk1, | |
1280 | struct task_struct *tsk2, | |
1281 | u32 perms) | |
1282 | { | |
1283 | struct task_security_struct *tsec1, *tsec2; | |
1284 | ||
1285 | tsec1 = tsk1->security; | |
1286 | tsec2 = tsk2->security; | |
1287 | return avc_has_perm(tsec1->sid, tsec2->sid, | |
1288 | SECCLASS_PROCESS, perms, NULL); | |
1289 | } | |
1290 | ||
b68e418c SS |
1291 | #if CAP_LAST_CAP > 63 |
1292 | #error Fix SELinux to handle capabilities > 63. | |
1293 | #endif | |
1294 | ||
1da177e4 LT |
1295 | /* Check whether a task is allowed to use a capability. */ |
1296 | static int task_has_capability(struct task_struct *tsk, | |
1297 | int cap) | |
1298 | { | |
1299 | struct task_security_struct *tsec; | |
1300 | struct avc_audit_data ad; | |
b68e418c SS |
1301 | u16 sclass; |
1302 | u32 av = CAP_TO_MASK(cap); | |
1da177e4 LT |
1303 | |
1304 | tsec = tsk->security; | |
1305 | ||
1306 | AVC_AUDIT_DATA_INIT(&ad,CAP); | |
1307 | ad.tsk = tsk; | |
1308 | ad.u.cap = cap; | |
1309 | ||
b68e418c SS |
1310 | switch (CAP_TO_INDEX(cap)) { |
1311 | case 0: | |
1312 | sclass = SECCLASS_CAPABILITY; | |
1313 | break; | |
1314 | case 1: | |
1315 | sclass = SECCLASS_CAPABILITY2; | |
1316 | break; | |
1317 | default: | |
1318 | printk(KERN_ERR | |
1319 | "SELinux: out of range capability %d\n", cap); | |
1320 | BUG(); | |
1321 | } | |
1322 | return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad); | |
1da177e4 LT |
1323 | } |
1324 | ||
1325 | /* Check whether a task is allowed to use a system operation. */ | |
1326 | static int task_has_system(struct task_struct *tsk, | |
1327 | u32 perms) | |
1328 | { | |
1329 | struct task_security_struct *tsec; | |
1330 | ||
1331 | tsec = tsk->security; | |
1332 | ||
1333 | return avc_has_perm(tsec->sid, SECINITSID_KERNEL, | |
1334 | SECCLASS_SYSTEM, perms, NULL); | |
1335 | } | |
1336 | ||
1337 | /* Check whether a task has a particular permission to an inode. | |
1338 | The 'adp' parameter is optional and allows other audit | |
1339 | data to be passed (e.g. the dentry). */ | |
1340 | static int inode_has_perm(struct task_struct *tsk, | |
1341 | struct inode *inode, | |
1342 | u32 perms, | |
1343 | struct avc_audit_data *adp) | |
1344 | { | |
1345 | struct task_security_struct *tsec; | |
1346 | struct inode_security_struct *isec; | |
1347 | struct avc_audit_data ad; | |
1348 | ||
bbaca6c2 SS |
1349 | if (unlikely (IS_PRIVATE (inode))) |
1350 | return 0; | |
1351 | ||
1da177e4 LT |
1352 | tsec = tsk->security; |
1353 | isec = inode->i_security; | |
1354 | ||
1355 | if (!adp) { | |
1356 | adp = &ad; | |
1357 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1358 | ad.u.fs.inode = inode; | |
1359 | } | |
1360 | ||
1361 | return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); | |
1362 | } | |
1363 | ||
1364 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1365 | the dentry to help the auditing code to more easily generate the | |
1366 | pathname if needed. */ | |
1367 | static inline int dentry_has_perm(struct task_struct *tsk, | |
1368 | struct vfsmount *mnt, | |
1369 | struct dentry *dentry, | |
1370 | u32 av) | |
1371 | { | |
1372 | struct inode *inode = dentry->d_inode; | |
1373 | struct avc_audit_data ad; | |
1374 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
44707fdf JB |
1375 | ad.u.fs.path.mnt = mnt; |
1376 | ad.u.fs.path.dentry = dentry; | |
1da177e4 LT |
1377 | return inode_has_perm(tsk, inode, av, &ad); |
1378 | } | |
1379 | ||
1380 | /* Check whether a task can use an open file descriptor to | |
1381 | access an inode in a given way. Check access to the | |
1382 | descriptor itself, and then use dentry_has_perm to | |
1383 | check a particular permission to the file. | |
1384 | Access to the descriptor is implicitly granted if it | |
1385 | has the same SID as the process. If av is zero, then | |
1386 | access to the file is not checked, e.g. for cases | |
1387 | where only the descriptor is affected like seek. */ | |
858119e1 | 1388 | static int file_has_perm(struct task_struct *tsk, |
1da177e4 LT |
1389 | struct file *file, |
1390 | u32 av) | |
1391 | { | |
1392 | struct task_security_struct *tsec = tsk->security; | |
1393 | struct file_security_struct *fsec = file->f_security; | |
44707fdf | 1394 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
1395 | struct avc_audit_data ad; |
1396 | int rc; | |
1397 | ||
1398 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1399 | ad.u.fs.path = file->f_path; |
1da177e4 LT |
1400 | |
1401 | if (tsec->sid != fsec->sid) { | |
1402 | rc = avc_has_perm(tsec->sid, fsec->sid, | |
1403 | SECCLASS_FD, | |
1404 | FD__USE, | |
1405 | &ad); | |
1406 | if (rc) | |
1407 | return rc; | |
1408 | } | |
1409 | ||
1410 | /* av is zero if only checking access to the descriptor. */ | |
1411 | if (av) | |
1412 | return inode_has_perm(tsk, inode, av, &ad); | |
1413 | ||
1414 | return 0; | |
1415 | } | |
1416 | ||
1417 | /* Check whether a task can create a file. */ | |
1418 | static int may_create(struct inode *dir, | |
1419 | struct dentry *dentry, | |
1420 | u16 tclass) | |
1421 | { | |
1422 | struct task_security_struct *tsec; | |
1423 | struct inode_security_struct *dsec; | |
1424 | struct superblock_security_struct *sbsec; | |
1425 | u32 newsid; | |
1426 | struct avc_audit_data ad; | |
1427 | int rc; | |
1428 | ||
1429 | tsec = current->security; | |
1430 | dsec = dir->i_security; | |
1431 | sbsec = dir->i_sb->s_security; | |
1432 | ||
1433 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1434 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
1435 | |
1436 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, | |
1437 | DIR__ADD_NAME | DIR__SEARCH, | |
1438 | &ad); | |
1439 | if (rc) | |
1440 | return rc; | |
1441 | ||
1442 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
1443 | newsid = tsec->create_sid; | |
1444 | } else { | |
1445 | rc = security_transition_sid(tsec->sid, dsec->sid, tclass, | |
1446 | &newsid); | |
1447 | if (rc) | |
1448 | return rc; | |
1449 | } | |
1450 | ||
1451 | rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); | |
1452 | if (rc) | |
1453 | return rc; | |
1454 | ||
1455 | return avc_has_perm(newsid, sbsec->sid, | |
1456 | SECCLASS_FILESYSTEM, | |
1457 | FILESYSTEM__ASSOCIATE, &ad); | |
1458 | } | |
1459 | ||
4eb582cf ML |
1460 | /* Check whether a task can create a key. */ |
1461 | static int may_create_key(u32 ksid, | |
1462 | struct task_struct *ctx) | |
1463 | { | |
1464 | struct task_security_struct *tsec; | |
1465 | ||
1466 | tsec = ctx->security; | |
1467 | ||
1468 | return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); | |
1469 | } | |
1470 | ||
1da177e4 LT |
1471 | #define MAY_LINK 0 |
1472 | #define MAY_UNLINK 1 | |
1473 | #define MAY_RMDIR 2 | |
1474 | ||
1475 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1476 | static int may_link(struct inode *dir, | |
1477 | struct dentry *dentry, | |
1478 | int kind) | |
1479 | ||
1480 | { | |
1481 | struct task_security_struct *tsec; | |
1482 | struct inode_security_struct *dsec, *isec; | |
1483 | struct avc_audit_data ad; | |
1484 | u32 av; | |
1485 | int rc; | |
1486 | ||
1487 | tsec = current->security; | |
1488 | dsec = dir->i_security; | |
1489 | isec = dentry->d_inode->i_security; | |
1490 | ||
1491 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1492 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
1493 | |
1494 | av = DIR__SEARCH; | |
1495 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
1496 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1497 | if (rc) | |
1498 | return rc; | |
1499 | ||
1500 | switch (kind) { | |
1501 | case MAY_LINK: | |
1502 | av = FILE__LINK; | |
1503 | break; | |
1504 | case MAY_UNLINK: | |
1505 | av = FILE__UNLINK; | |
1506 | break; | |
1507 | case MAY_RMDIR: | |
1508 | av = DIR__RMDIR; | |
1509 | break; | |
1510 | default: | |
1511 | printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); | |
1512 | return 0; | |
1513 | } | |
1514 | ||
1515 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); | |
1516 | return rc; | |
1517 | } | |
1518 | ||
1519 | static inline int may_rename(struct inode *old_dir, | |
1520 | struct dentry *old_dentry, | |
1521 | struct inode *new_dir, | |
1522 | struct dentry *new_dentry) | |
1523 | { | |
1524 | struct task_security_struct *tsec; | |
1525 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; | |
1526 | struct avc_audit_data ad; | |
1527 | u32 av; | |
1528 | int old_is_dir, new_is_dir; | |
1529 | int rc; | |
1530 | ||
1531 | tsec = current->security; | |
1532 | old_dsec = old_dir->i_security; | |
1533 | old_isec = old_dentry->d_inode->i_security; | |
1534 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1535 | new_dsec = new_dir->i_security; | |
1536 | ||
1537 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1538 | ||
44707fdf | 1539 | ad.u.fs.path.dentry = old_dentry; |
1da177e4 LT |
1540 | rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, |
1541 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); | |
1542 | if (rc) | |
1543 | return rc; | |
1544 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1545 | old_isec->sclass, FILE__RENAME, &ad); | |
1546 | if (rc) | |
1547 | return rc; | |
1548 | if (old_is_dir && new_dir != old_dir) { | |
1549 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1550 | old_isec->sclass, DIR__REPARENT, &ad); | |
1551 | if (rc) | |
1552 | return rc; | |
1553 | } | |
1554 | ||
44707fdf | 1555 | ad.u.fs.path.dentry = new_dentry; |
1da177e4 LT |
1556 | av = DIR__ADD_NAME | DIR__SEARCH; |
1557 | if (new_dentry->d_inode) | |
1558 | av |= DIR__REMOVE_NAME; | |
1559 | rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1560 | if (rc) | |
1561 | return rc; | |
1562 | if (new_dentry->d_inode) { | |
1563 | new_isec = new_dentry->d_inode->i_security; | |
1564 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
1565 | rc = avc_has_perm(tsec->sid, new_isec->sid, | |
1566 | new_isec->sclass, | |
1567 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1568 | if (rc) | |
1569 | return rc; | |
1570 | } | |
1571 | ||
1572 | return 0; | |
1573 | } | |
1574 | ||
1575 | /* Check whether a task can perform a filesystem operation. */ | |
1576 | static int superblock_has_perm(struct task_struct *tsk, | |
1577 | struct super_block *sb, | |
1578 | u32 perms, | |
1579 | struct avc_audit_data *ad) | |
1580 | { | |
1581 | struct task_security_struct *tsec; | |
1582 | struct superblock_security_struct *sbsec; | |
1583 | ||
1584 | tsec = tsk->security; | |
1585 | sbsec = sb->s_security; | |
1586 | return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
1587 | perms, ad); | |
1588 | } | |
1589 | ||
1590 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1591 | static inline u32 file_mask_to_av(int mode, int mask) | |
1592 | { | |
1593 | u32 av = 0; | |
1594 | ||
1595 | if ((mode & S_IFMT) != S_IFDIR) { | |
1596 | if (mask & MAY_EXEC) | |
1597 | av |= FILE__EXECUTE; | |
1598 | if (mask & MAY_READ) | |
1599 | av |= FILE__READ; | |
1600 | ||
1601 | if (mask & MAY_APPEND) | |
1602 | av |= FILE__APPEND; | |
1603 | else if (mask & MAY_WRITE) | |
1604 | av |= FILE__WRITE; | |
1605 | ||
1606 | } else { | |
1607 | if (mask & MAY_EXEC) | |
1608 | av |= DIR__SEARCH; | |
1609 | if (mask & MAY_WRITE) | |
1610 | av |= DIR__WRITE; | |
1611 | if (mask & MAY_READ) | |
1612 | av |= DIR__READ; | |
1613 | } | |
1614 | ||
1615 | return av; | |
1616 | } | |
1617 | ||
1618 | /* Convert a Linux file to an access vector. */ | |
1619 | static inline u32 file_to_av(struct file *file) | |
1620 | { | |
1621 | u32 av = 0; | |
1622 | ||
1623 | if (file->f_mode & FMODE_READ) | |
1624 | av |= FILE__READ; | |
1625 | if (file->f_mode & FMODE_WRITE) { | |
1626 | if (file->f_flags & O_APPEND) | |
1627 | av |= FILE__APPEND; | |
1628 | else | |
1629 | av |= FILE__WRITE; | |
1630 | } | |
0794c66d SS |
1631 | if (!av) { |
1632 | /* | |
1633 | * Special file opened with flags 3 for ioctl-only use. | |
1634 | */ | |
1635 | av = FILE__IOCTL; | |
1636 | } | |
1da177e4 LT |
1637 | |
1638 | return av; | |
1639 | } | |
1640 | ||
1da177e4 LT |
1641 | /* Hook functions begin here. */ |
1642 | ||
1643 | static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) | |
1644 | { | |
1645 | struct task_security_struct *psec = parent->security; | |
1646 | struct task_security_struct *csec = child->security; | |
1647 | int rc; | |
1648 | ||
1649 | rc = secondary_ops->ptrace(parent,child); | |
1650 | if (rc) | |
1651 | return rc; | |
1652 | ||
1653 | rc = task_has_perm(parent, child, PROCESS__PTRACE); | |
1654 | /* Save the SID of the tracing process for later use in apply_creds. */ | |
341c2d80 | 1655 | if (!(child->ptrace & PT_PTRACED) && !rc) |
1da177e4 LT |
1656 | csec->ptrace_sid = psec->sid; |
1657 | return rc; | |
1658 | } | |
1659 | ||
1660 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
1661 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1662 | { | |
1663 | int error; | |
1664 | ||
1665 | error = task_has_perm(current, target, PROCESS__GETCAP); | |
1666 | if (error) | |
1667 | return error; | |
1668 | ||
1669 | return secondary_ops->capget(target, effective, inheritable, permitted); | |
1670 | } | |
1671 | ||
1672 | static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, | |
1673 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1674 | { | |
1675 | int error; | |
1676 | ||
1677 | error = secondary_ops->capset_check(target, effective, inheritable, permitted); | |
1678 | if (error) | |
1679 | return error; | |
1680 | ||
1681 | return task_has_perm(current, target, PROCESS__SETCAP); | |
1682 | } | |
1683 | ||
1684 | static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, | |
1685 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1686 | { | |
1687 | secondary_ops->capset_set(target, effective, inheritable, permitted); | |
1688 | } | |
1689 | ||
1690 | static int selinux_capable(struct task_struct *tsk, int cap) | |
1691 | { | |
1692 | int rc; | |
1693 | ||
1694 | rc = secondary_ops->capable(tsk, cap); | |
1695 | if (rc) | |
1696 | return rc; | |
1697 | ||
1698 | return task_has_capability(tsk,cap); | |
1699 | } | |
1700 | ||
3fbfa981 EB |
1701 | static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) |
1702 | { | |
1703 | int buflen, rc; | |
1704 | char *buffer, *path, *end; | |
1705 | ||
1706 | rc = -ENOMEM; | |
1707 | buffer = (char*)__get_free_page(GFP_KERNEL); | |
1708 | if (!buffer) | |
1709 | goto out; | |
1710 | ||
1711 | buflen = PAGE_SIZE; | |
1712 | end = buffer+buflen; | |
1713 | *--end = '\0'; | |
1714 | buflen--; | |
1715 | path = end-1; | |
1716 | *path = '/'; | |
1717 | while (table) { | |
1718 | const char *name = table->procname; | |
1719 | size_t namelen = strlen(name); | |
1720 | buflen -= namelen + 1; | |
1721 | if (buflen < 0) | |
1722 | goto out_free; | |
1723 | end -= namelen; | |
1724 | memcpy(end, name, namelen); | |
1725 | *--end = '/'; | |
1726 | path = end; | |
1727 | table = table->parent; | |
1728 | } | |
b599fdfd EB |
1729 | buflen -= 4; |
1730 | if (buflen < 0) | |
1731 | goto out_free; | |
1732 | end -= 4; | |
1733 | memcpy(end, "/sys", 4); | |
1734 | path = end; | |
3fbfa981 EB |
1735 | rc = security_genfs_sid("proc", path, tclass, sid); |
1736 | out_free: | |
1737 | free_page((unsigned long)buffer); | |
1738 | out: | |
1739 | return rc; | |
1740 | } | |
1741 | ||
1da177e4 LT |
1742 | static int selinux_sysctl(ctl_table *table, int op) |
1743 | { | |
1744 | int error = 0; | |
1745 | u32 av; | |
1746 | struct task_security_struct *tsec; | |
1747 | u32 tsid; | |
1748 | int rc; | |
1749 | ||
1750 | rc = secondary_ops->sysctl(table, op); | |
1751 | if (rc) | |
1752 | return rc; | |
1753 | ||
1754 | tsec = current->security; | |
1755 | ||
3fbfa981 EB |
1756 | rc = selinux_sysctl_get_sid(table, (op == 0001) ? |
1757 | SECCLASS_DIR : SECCLASS_FILE, &tsid); | |
1da177e4 LT |
1758 | if (rc) { |
1759 | /* Default to the well-defined sysctl SID. */ | |
1760 | tsid = SECINITSID_SYSCTL; | |
1761 | } | |
1762 | ||
1763 | /* The op values are "defined" in sysctl.c, thereby creating | |
1764 | * a bad coupling between this module and sysctl.c */ | |
1765 | if(op == 001) { | |
1766 | error = avc_has_perm(tsec->sid, tsid, | |
1767 | SECCLASS_DIR, DIR__SEARCH, NULL); | |
1768 | } else { | |
1769 | av = 0; | |
1770 | if (op & 004) | |
1771 | av |= FILE__READ; | |
1772 | if (op & 002) | |
1773 | av |= FILE__WRITE; | |
1774 | if (av) | |
1775 | error = avc_has_perm(tsec->sid, tsid, | |
1776 | SECCLASS_FILE, av, NULL); | |
1777 | } | |
1778 | ||
1779 | return error; | |
1780 | } | |
1781 | ||
1782 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
1783 | { | |
1784 | int rc = 0; | |
1785 | ||
1786 | if (!sb) | |
1787 | return 0; | |
1788 | ||
1789 | switch (cmds) { | |
1790 | case Q_SYNC: | |
1791 | case Q_QUOTAON: | |
1792 | case Q_QUOTAOFF: | |
1793 | case Q_SETINFO: | |
1794 | case Q_SETQUOTA: | |
1795 | rc = superblock_has_perm(current, | |
1796 | sb, | |
1797 | FILESYSTEM__QUOTAMOD, NULL); | |
1798 | break; | |
1799 | case Q_GETFMT: | |
1800 | case Q_GETINFO: | |
1801 | case Q_GETQUOTA: | |
1802 | rc = superblock_has_perm(current, | |
1803 | sb, | |
1804 | FILESYSTEM__QUOTAGET, NULL); | |
1805 | break; | |
1806 | default: | |
1807 | rc = 0; /* let the kernel handle invalid cmds */ | |
1808 | break; | |
1809 | } | |
1810 | return rc; | |
1811 | } | |
1812 | ||
1813 | static int selinux_quota_on(struct dentry *dentry) | |
1814 | { | |
1815 | return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); | |
1816 | } | |
1817 | ||
1818 | static int selinux_syslog(int type) | |
1819 | { | |
1820 | int rc; | |
1821 | ||
1822 | rc = secondary_ops->syslog(type); | |
1823 | if (rc) | |
1824 | return rc; | |
1825 | ||
1826 | switch (type) { | |
1827 | case 3: /* Read last kernel messages */ | |
1828 | case 10: /* Return size of the log buffer */ | |
1829 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); | |
1830 | break; | |
1831 | case 6: /* Disable logging to console */ | |
1832 | case 7: /* Enable logging to console */ | |
1833 | case 8: /* Set level of messages printed to console */ | |
1834 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); | |
1835 | break; | |
1836 | case 0: /* Close log */ | |
1837 | case 1: /* Open log */ | |
1838 | case 2: /* Read from log */ | |
1839 | case 4: /* Read/clear last kernel messages */ | |
1840 | case 5: /* Clear ring buffer */ | |
1841 | default: | |
1842 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
1843 | break; | |
1844 | } | |
1845 | return rc; | |
1846 | } | |
1847 | ||
1848 | /* | |
1849 | * Check that a process has enough memory to allocate a new virtual | |
1850 | * mapping. 0 means there is enough memory for the allocation to | |
1851 | * succeed and -ENOMEM implies there is not. | |
1852 | * | |
1853 | * Note that secondary_ops->capable and task_has_perm_noaudit return 0 | |
1854 | * if the capability is granted, but __vm_enough_memory requires 1 if | |
1855 | * the capability is granted. | |
1856 | * | |
1857 | * Do not audit the selinux permission check, as this is applied to all | |
1858 | * processes that allocate mappings. | |
1859 | */ | |
34b4e4aa | 1860 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
1861 | { |
1862 | int rc, cap_sys_admin = 0; | |
1863 | struct task_security_struct *tsec = current->security; | |
1864 | ||
1865 | rc = secondary_ops->capable(current, CAP_SYS_ADMIN); | |
1866 | if (rc == 0) | |
1867 | rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, | |
2c3c05db SS |
1868 | SECCLASS_CAPABILITY, |
1869 | CAP_TO_MASK(CAP_SYS_ADMIN), | |
1870 | 0, | |
1871 | NULL); | |
1da177e4 LT |
1872 | |
1873 | if (rc == 0) | |
1874 | cap_sys_admin = 1; | |
1875 | ||
34b4e4aa | 1876 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
1877 | } |
1878 | ||
1879 | /* binprm security operations */ | |
1880 | ||
1881 | static int selinux_bprm_alloc_security(struct linux_binprm *bprm) | |
1882 | { | |
1883 | struct bprm_security_struct *bsec; | |
1884 | ||
89d155ef | 1885 | bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); |
1da177e4 LT |
1886 | if (!bsec) |
1887 | return -ENOMEM; | |
1888 | ||
1da177e4 LT |
1889 | bsec->sid = SECINITSID_UNLABELED; |
1890 | bsec->set = 0; | |
1891 | ||
1892 | bprm->security = bsec; | |
1893 | return 0; | |
1894 | } | |
1895 | ||
1896 | static int selinux_bprm_set_security(struct linux_binprm *bprm) | |
1897 | { | |
1898 | struct task_security_struct *tsec; | |
3d5ff529 | 1899 | struct inode *inode = bprm->file->f_path.dentry->d_inode; |
1da177e4 LT |
1900 | struct inode_security_struct *isec; |
1901 | struct bprm_security_struct *bsec; | |
1902 | u32 newsid; | |
1903 | struct avc_audit_data ad; | |
1904 | int rc; | |
1905 | ||
1906 | rc = secondary_ops->bprm_set_security(bprm); | |
1907 | if (rc) | |
1908 | return rc; | |
1909 | ||
1910 | bsec = bprm->security; | |
1911 | ||
1912 | if (bsec->set) | |
1913 | return 0; | |
1914 | ||
1915 | tsec = current->security; | |
1916 | isec = inode->i_security; | |
1917 | ||
1918 | /* Default to the current task SID. */ | |
1919 | bsec->sid = tsec->sid; | |
1920 | ||
28eba5bf | 1921 | /* Reset fs, key, and sock SIDs on execve. */ |
1da177e4 | 1922 | tsec->create_sid = 0; |
28eba5bf | 1923 | tsec->keycreate_sid = 0; |
42c3e03e | 1924 | tsec->sockcreate_sid = 0; |
1da177e4 LT |
1925 | |
1926 | if (tsec->exec_sid) { | |
1927 | newsid = tsec->exec_sid; | |
1928 | /* Reset exec SID on execve. */ | |
1929 | tsec->exec_sid = 0; | |
1930 | } else { | |
1931 | /* Check for a default transition on this program. */ | |
1932 | rc = security_transition_sid(tsec->sid, isec->sid, | |
1933 | SECCLASS_PROCESS, &newsid); | |
1934 | if (rc) | |
1935 | return rc; | |
1936 | } | |
1937 | ||
1938 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1939 | ad.u.fs.path = bprm->file->f_path; |
1da177e4 | 1940 | |
3d5ff529 | 1941 | if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
1da177e4 LT |
1942 | newsid = tsec->sid; |
1943 | ||
1944 | if (tsec->sid == newsid) { | |
1945 | rc = avc_has_perm(tsec->sid, isec->sid, | |
1946 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); | |
1947 | if (rc) | |
1948 | return rc; | |
1949 | } else { | |
1950 | /* Check permissions for the transition. */ | |
1951 | rc = avc_has_perm(tsec->sid, newsid, | |
1952 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); | |
1953 | if (rc) | |
1954 | return rc; | |
1955 | ||
1956 | rc = avc_has_perm(newsid, isec->sid, | |
1957 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); | |
1958 | if (rc) | |
1959 | return rc; | |
1960 | ||
1961 | /* Clear any possibly unsafe personality bits on exec: */ | |
1962 | current->personality &= ~PER_CLEAR_ON_SETID; | |
1963 | ||
1964 | /* Set the security field to the new SID. */ | |
1965 | bsec->sid = newsid; | |
1966 | } | |
1967 | ||
1968 | bsec->set = 1; | |
1969 | return 0; | |
1970 | } | |
1971 | ||
1972 | static int selinux_bprm_check_security (struct linux_binprm *bprm) | |
1973 | { | |
1974 | return secondary_ops->bprm_check_security(bprm); | |
1975 | } | |
1976 | ||
1977 | ||
1978 | static int selinux_bprm_secureexec (struct linux_binprm *bprm) | |
1979 | { | |
1980 | struct task_security_struct *tsec = current->security; | |
1981 | int atsecure = 0; | |
1982 | ||
1983 | if (tsec->osid != tsec->sid) { | |
1984 | /* Enable secure mode for SIDs transitions unless | |
1985 | the noatsecure permission is granted between | |
1986 | the two SIDs, i.e. ahp returns 0. */ | |
1987 | atsecure = avc_has_perm(tsec->osid, tsec->sid, | |
1988 | SECCLASS_PROCESS, | |
1989 | PROCESS__NOATSECURE, NULL); | |
1990 | } | |
1991 | ||
1992 | return (atsecure || secondary_ops->bprm_secureexec(bprm)); | |
1993 | } | |
1994 | ||
1995 | static void selinux_bprm_free_security(struct linux_binprm *bprm) | |
1996 | { | |
9a5f04bf | 1997 | kfree(bprm->security); |
1da177e4 | 1998 | bprm->security = NULL; |
1da177e4 LT |
1999 | } |
2000 | ||
2001 | extern struct vfsmount *selinuxfs_mount; | |
2002 | extern struct dentry *selinux_null; | |
2003 | ||
2004 | /* Derived from fs/exec.c:flush_old_files. */ | |
2005 | static inline void flush_unauthorized_files(struct files_struct * files) | |
2006 | { | |
2007 | struct avc_audit_data ad; | |
2008 | struct file *file, *devnull = NULL; | |
b20c8122 | 2009 | struct tty_struct *tty; |
badf1662 | 2010 | struct fdtable *fdt; |
1da177e4 | 2011 | long j = -1; |
24ec839c | 2012 | int drop_tty = 0; |
1da177e4 | 2013 | |
b20c8122 | 2014 | mutex_lock(&tty_mutex); |
24ec839c | 2015 | tty = get_current_tty(); |
1da177e4 LT |
2016 | if (tty) { |
2017 | file_list_lock(); | |
2f512016 | 2018 | file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); |
1da177e4 LT |
2019 | if (file) { |
2020 | /* Revalidate access to controlling tty. | |
2021 | Use inode_has_perm on the tty inode directly rather | |
2022 | than using file_has_perm, as this particular open | |
2023 | file may belong to another process and we are only | |
2024 | interested in the inode-based check here. */ | |
3d5ff529 | 2025 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2026 | if (inode_has_perm(current, inode, |
2027 | FILE__READ | FILE__WRITE, NULL)) { | |
24ec839c | 2028 | drop_tty = 1; |
1da177e4 LT |
2029 | } |
2030 | } | |
2031 | file_list_unlock(); | |
2032 | } | |
b20c8122 | 2033 | mutex_unlock(&tty_mutex); |
98a27ba4 EB |
2034 | /* Reset controlling tty. */ |
2035 | if (drop_tty) | |
2036 | no_tty(); | |
1da177e4 LT |
2037 | |
2038 | /* Revalidate access to inherited open files. */ | |
2039 | ||
2040 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
2041 | ||
2042 | spin_lock(&files->file_lock); | |
2043 | for (;;) { | |
2044 | unsigned long set, i; | |
2045 | int fd; | |
2046 | ||
2047 | j++; | |
2048 | i = j * __NFDBITS; | |
badf1662 | 2049 | fdt = files_fdtable(files); |
bbea9f69 | 2050 | if (i >= fdt->max_fds) |
1da177e4 | 2051 | break; |
badf1662 | 2052 | set = fdt->open_fds->fds_bits[j]; |
1da177e4 LT |
2053 | if (!set) |
2054 | continue; | |
2055 | spin_unlock(&files->file_lock); | |
2056 | for ( ; set ; i++,set >>= 1) { | |
2057 | if (set & 1) { | |
2058 | file = fget(i); | |
2059 | if (!file) | |
2060 | continue; | |
2061 | if (file_has_perm(current, | |
2062 | file, | |
2063 | file_to_av(file))) { | |
2064 | sys_close(i); | |
2065 | fd = get_unused_fd(); | |
2066 | if (fd != i) { | |
2067 | if (fd >= 0) | |
2068 | put_unused_fd(fd); | |
2069 | fput(file); | |
2070 | continue; | |
2071 | } | |
2072 | if (devnull) { | |
095975da | 2073 | get_file(devnull); |
1da177e4 LT |
2074 | } else { |
2075 | devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); | |
fc5d81e6 AM |
2076 | if (IS_ERR(devnull)) { |
2077 | devnull = NULL; | |
1da177e4 LT |
2078 | put_unused_fd(fd); |
2079 | fput(file); | |
2080 | continue; | |
2081 | } | |
2082 | } | |
2083 | fd_install(fd, devnull); | |
2084 | } | |
2085 | fput(file); | |
2086 | } | |
2087 | } | |
2088 | spin_lock(&files->file_lock); | |
2089 | ||
2090 | } | |
2091 | spin_unlock(&files->file_lock); | |
2092 | } | |
2093 | ||
2094 | static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) | |
2095 | { | |
2096 | struct task_security_struct *tsec; | |
2097 | struct bprm_security_struct *bsec; | |
2098 | u32 sid; | |
2099 | int rc; | |
2100 | ||
2101 | secondary_ops->bprm_apply_creds(bprm, unsafe); | |
2102 | ||
2103 | tsec = current->security; | |
2104 | ||
2105 | bsec = bprm->security; | |
2106 | sid = bsec->sid; | |
2107 | ||
2108 | tsec->osid = tsec->sid; | |
2109 | bsec->unsafe = 0; | |
2110 | if (tsec->sid != sid) { | |
2111 | /* Check for shared state. If not ok, leave SID | |
2112 | unchanged and kill. */ | |
2113 | if (unsafe & LSM_UNSAFE_SHARE) { | |
2114 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, | |
2115 | PROCESS__SHARE, NULL); | |
2116 | if (rc) { | |
2117 | bsec->unsafe = 1; | |
2118 | return; | |
2119 | } | |
2120 | } | |
2121 | ||
2122 | /* Check for ptracing, and update the task SID if ok. | |
2123 | Otherwise, leave SID unchanged and kill. */ | |
2124 | if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2125 | rc = avc_has_perm(tsec->ptrace_sid, sid, | |
2126 | SECCLASS_PROCESS, PROCESS__PTRACE, | |
2127 | NULL); | |
2128 | if (rc) { | |
2129 | bsec->unsafe = 1; | |
2130 | return; | |
2131 | } | |
2132 | } | |
2133 | tsec->sid = sid; | |
2134 | } | |
2135 | } | |
2136 | ||
2137 | /* | |
2138 | * called after apply_creds without the task lock held | |
2139 | */ | |
2140 | static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) | |
2141 | { | |
2142 | struct task_security_struct *tsec; | |
2143 | struct rlimit *rlim, *initrlim; | |
2144 | struct itimerval itimer; | |
2145 | struct bprm_security_struct *bsec; | |
2146 | int rc, i; | |
2147 | ||
2148 | tsec = current->security; | |
2149 | bsec = bprm->security; | |
2150 | ||
2151 | if (bsec->unsafe) { | |
2152 | force_sig_specific(SIGKILL, current); | |
2153 | return; | |
2154 | } | |
2155 | if (tsec->osid == tsec->sid) | |
2156 | return; | |
2157 | ||
2158 | /* Close files for which the new task SID is not authorized. */ | |
2159 | flush_unauthorized_files(current->files); | |
2160 | ||
2161 | /* Check whether the new SID can inherit signal state | |
2162 | from the old SID. If not, clear itimers to avoid | |
2163 | subsequent signal generation and flush and unblock | |
2164 | signals. This must occur _after_ the task SID has | |
2165 | been updated so that any kill done after the flush | |
2166 | will be checked against the new SID. */ | |
2167 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2168 | PROCESS__SIGINH, NULL); | |
2169 | if (rc) { | |
2170 | memset(&itimer, 0, sizeof itimer); | |
2171 | for (i = 0; i < 3; i++) | |
2172 | do_setitimer(i, &itimer, NULL); | |
2173 | flush_signals(current); | |
2174 | spin_lock_irq(¤t->sighand->siglock); | |
2175 | flush_signal_handlers(current, 1); | |
2176 | sigemptyset(¤t->blocked); | |
2177 | recalc_sigpending(); | |
2178 | spin_unlock_irq(¤t->sighand->siglock); | |
2179 | } | |
2180 | ||
4ac212ad SS |
2181 | /* Always clear parent death signal on SID transitions. */ |
2182 | current->pdeath_signal = 0; | |
2183 | ||
1da177e4 LT |
2184 | /* Check whether the new SID can inherit resource limits |
2185 | from the old SID. If not, reset all soft limits to | |
2186 | the lower of the current task's hard limit and the init | |
2187 | task's soft limit. Note that the setting of hard limits | |
2188 | (even to lower them) can be controlled by the setrlimit | |
2189 | check. The inclusion of the init task's soft limit into | |
2190 | the computation is to avoid resetting soft limits higher | |
2191 | than the default soft limit for cases where the default | |
2192 | is lower than the hard limit, e.g. RLIMIT_CORE or | |
2193 | RLIMIT_STACK.*/ | |
2194 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2195 | PROCESS__RLIMITINH, NULL); | |
2196 | if (rc) { | |
2197 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
2198 | rlim = current->signal->rlim + i; | |
2199 | initrlim = init_task.signal->rlim+i; | |
2200 | rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); | |
2201 | } | |
2202 | if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { | |
2203 | /* | |
2204 | * This will cause RLIMIT_CPU calculations | |
2205 | * to be refigured. | |
2206 | */ | |
2207 | current->it_prof_expires = jiffies_to_cputime(1); | |
2208 | } | |
2209 | } | |
2210 | ||
2211 | /* Wake up the parent if it is waiting so that it can | |
2212 | recheck wait permission to the new task SID. */ | |
2213 | wake_up_interruptible(¤t->parent->signal->wait_chldexit); | |
2214 | } | |
2215 | ||
2216 | /* superblock security operations */ | |
2217 | ||
2218 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2219 | { | |
2220 | return superblock_alloc_security(sb); | |
2221 | } | |
2222 | ||
2223 | static void selinux_sb_free_security(struct super_block *sb) | |
2224 | { | |
2225 | superblock_free_security(sb); | |
2226 | } | |
2227 | ||
2228 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2229 | { | |
2230 | if (plen > olen) | |
2231 | return 0; | |
2232 | ||
2233 | return !memcmp(prefix, option, plen); | |
2234 | } | |
2235 | ||
2236 | static inline int selinux_option(char *option, int len) | |
2237 | { | |
2238 | return (match_prefix("context=", sizeof("context=")-1, option, len) || | |
2239 | match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || | |
0808925e EP |
2240 | match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) || |
2241 | match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len)); | |
1da177e4 LT |
2242 | } |
2243 | ||
2244 | static inline void take_option(char **to, char *from, int *first, int len) | |
2245 | { | |
2246 | if (!*first) { | |
2247 | **to = ','; | |
2248 | *to += 1; | |
3528a953 | 2249 | } else |
1da177e4 LT |
2250 | *first = 0; |
2251 | memcpy(*to, from, len); | |
2252 | *to += len; | |
2253 | } | |
2254 | ||
3528a953 CO |
2255 | static inline void take_selinux_option(char **to, char *from, int *first, |
2256 | int len) | |
2257 | { | |
2258 | int current_size = 0; | |
2259 | ||
2260 | if (!*first) { | |
2261 | **to = '|'; | |
2262 | *to += 1; | |
2263 | } | |
2264 | else | |
2265 | *first = 0; | |
2266 | ||
2267 | while (current_size < len) { | |
2268 | if (*from != '"') { | |
2269 | **to = *from; | |
2270 | *to += 1; | |
2271 | } | |
2272 | from += 1; | |
2273 | current_size += 1; | |
2274 | } | |
2275 | } | |
2276 | ||
e0007529 | 2277 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2278 | { |
2279 | int fnosec, fsec, rc = 0; | |
2280 | char *in_save, *in_curr, *in_end; | |
2281 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2282 | int open_quote = 0; |
1da177e4 LT |
2283 | |
2284 | in_curr = orig; | |
2285 | sec_curr = copy; | |
2286 | ||
1da177e4 LT |
2287 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2288 | if (!nosec) { | |
2289 | rc = -ENOMEM; | |
2290 | goto out; | |
2291 | } | |
2292 | ||
2293 | nosec_save = nosec; | |
2294 | fnosec = fsec = 1; | |
2295 | in_save = in_end = orig; | |
2296 | ||
2297 | do { | |
3528a953 CO |
2298 | if (*in_end == '"') |
2299 | open_quote = !open_quote; | |
2300 | if ((*in_end == ',' && open_quote == 0) || | |
2301 | *in_end == '\0') { | |
1da177e4 LT |
2302 | int len = in_end - in_curr; |
2303 | ||
2304 | if (selinux_option(in_curr, len)) | |
3528a953 | 2305 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2306 | else |
2307 | take_option(&nosec, in_curr, &fnosec, len); | |
2308 | ||
2309 | in_curr = in_end + 1; | |
2310 | } | |
2311 | } while (*in_end++); | |
2312 | ||
6931dfc9 | 2313 | strcpy(in_save, nosec_save); |
da3caa20 | 2314 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2315 | out: |
2316 | return rc; | |
2317 | } | |
2318 | ||
2319 | static int selinux_sb_kern_mount(struct super_block *sb, void *data) | |
2320 | { | |
2321 | struct avc_audit_data ad; | |
2322 | int rc; | |
2323 | ||
2324 | rc = superblock_doinit(sb, data); | |
2325 | if (rc) | |
2326 | return rc; | |
2327 | ||
2328 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
44707fdf | 2329 | ad.u.fs.path.dentry = sb->s_root; |
1da177e4 LT |
2330 | return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); |
2331 | } | |
2332 | ||
726c3342 | 2333 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 LT |
2334 | { |
2335 | struct avc_audit_data ad; | |
2336 | ||
2337 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
44707fdf | 2338 | ad.u.fs.path.dentry = dentry->d_sb->s_root; |
726c3342 | 2339 | return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2340 | } |
2341 | ||
2342 | static int selinux_mount(char * dev_name, | |
2343 | struct nameidata *nd, | |
2344 | char * type, | |
2345 | unsigned long flags, | |
2346 | void * data) | |
2347 | { | |
2348 | int rc; | |
2349 | ||
2350 | rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); | |
2351 | if (rc) | |
2352 | return rc; | |
2353 | ||
2354 | if (flags & MS_REMOUNT) | |
4ac91378 | 2355 | return superblock_has_perm(current, nd->path.mnt->mnt_sb, |
1da177e4 LT |
2356 | FILESYSTEM__REMOUNT, NULL); |
2357 | else | |
4ac91378 | 2358 | return dentry_has_perm(current, nd->path.mnt, nd->path.dentry, |
1da177e4 LT |
2359 | FILE__MOUNTON); |
2360 | } | |
2361 | ||
2362 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2363 | { | |
2364 | int rc; | |
2365 | ||
2366 | rc = secondary_ops->sb_umount(mnt, flags); | |
2367 | if (rc) | |
2368 | return rc; | |
2369 | ||
2370 | return superblock_has_perm(current,mnt->mnt_sb, | |
2371 | FILESYSTEM__UNMOUNT,NULL); | |
2372 | } | |
2373 | ||
2374 | /* inode security operations */ | |
2375 | ||
2376 | static int selinux_inode_alloc_security(struct inode *inode) | |
2377 | { | |
2378 | return inode_alloc_security(inode); | |
2379 | } | |
2380 | ||
2381 | static void selinux_inode_free_security(struct inode *inode) | |
2382 | { | |
2383 | inode_free_security(inode); | |
2384 | } | |
2385 | ||
5e41ff9e SS |
2386 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
2387 | char **name, void **value, | |
2388 | size_t *len) | |
2389 | { | |
2390 | struct task_security_struct *tsec; | |
2391 | struct inode_security_struct *dsec; | |
2392 | struct superblock_security_struct *sbsec; | |
570bc1c2 | 2393 | u32 newsid, clen; |
5e41ff9e | 2394 | int rc; |
570bc1c2 | 2395 | char *namep = NULL, *context; |
5e41ff9e SS |
2396 | |
2397 | tsec = current->security; | |
2398 | dsec = dir->i_security; | |
2399 | sbsec = dir->i_sb->s_security; | |
5e41ff9e SS |
2400 | |
2401 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2402 | newsid = tsec->create_sid; | |
2403 | } else { | |
2404 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2405 | inode_mode_to_security_class(inode->i_mode), | |
2406 | &newsid); | |
2407 | if (rc) { | |
2408 | printk(KERN_WARNING "%s: " | |
2409 | "security_transition_sid failed, rc=%d (dev=%s " | |
2410 | "ino=%ld)\n", | |
2411 | __FUNCTION__, | |
2412 | -rc, inode->i_sb->s_id, inode->i_ino); | |
2413 | return rc; | |
2414 | } | |
2415 | } | |
2416 | ||
296fddf7 EP |
2417 | /* Possibly defer initialization to selinux_complete_init. */ |
2418 | if (sbsec->initialized) { | |
2419 | struct inode_security_struct *isec = inode->i_security; | |
2420 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2421 | isec->sid = newsid; | |
2422 | isec->initialized = 1; | |
2423 | } | |
5e41ff9e | 2424 | |
8aad3875 | 2425 | if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) |
25a74f3b SS |
2426 | return -EOPNOTSUPP; |
2427 | ||
570bc1c2 | 2428 | if (name) { |
a02fe132 | 2429 | namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); |
570bc1c2 SS |
2430 | if (!namep) |
2431 | return -ENOMEM; | |
2432 | *name = namep; | |
2433 | } | |
5e41ff9e | 2434 | |
570bc1c2 SS |
2435 | if (value && len) { |
2436 | rc = security_sid_to_context(newsid, &context, &clen); | |
2437 | if (rc) { | |
2438 | kfree(namep); | |
2439 | return rc; | |
2440 | } | |
2441 | *value = context; | |
2442 | *len = clen; | |
5e41ff9e | 2443 | } |
5e41ff9e | 2444 | |
5e41ff9e SS |
2445 | return 0; |
2446 | } | |
2447 | ||
1da177e4 LT |
2448 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
2449 | { | |
2450 | return may_create(dir, dentry, SECCLASS_FILE); | |
2451 | } | |
2452 | ||
1da177e4 LT |
2453 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2454 | { | |
2455 | int rc; | |
2456 | ||
2457 | rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); | |
2458 | if (rc) | |
2459 | return rc; | |
2460 | return may_link(dir, old_dentry, MAY_LINK); | |
2461 | } | |
2462 | ||
1da177e4 LT |
2463 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2464 | { | |
2465 | int rc; | |
2466 | ||
2467 | rc = secondary_ops->inode_unlink(dir, dentry); | |
2468 | if (rc) | |
2469 | return rc; | |
2470 | return may_link(dir, dentry, MAY_UNLINK); | |
2471 | } | |
2472 | ||
2473 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2474 | { | |
2475 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2476 | } | |
2477 | ||
1da177e4 LT |
2478 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
2479 | { | |
2480 | return may_create(dir, dentry, SECCLASS_DIR); | |
2481 | } | |
2482 | ||
1da177e4 LT |
2483 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2484 | { | |
2485 | return may_link(dir, dentry, MAY_RMDIR); | |
2486 | } | |
2487 | ||
2488 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
2489 | { | |
2490 | int rc; | |
2491 | ||
2492 | rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); | |
2493 | if (rc) | |
2494 | return rc; | |
2495 | ||
2496 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); | |
2497 | } | |
2498 | ||
1da177e4 LT |
2499 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
2500 | struct inode *new_inode, struct dentry *new_dentry) | |
2501 | { | |
2502 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2503 | } | |
2504 | ||
1da177e4 LT |
2505 | static int selinux_inode_readlink(struct dentry *dentry) |
2506 | { | |
2507 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2508 | } | |
2509 | ||
2510 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2511 | { | |
2512 | int rc; | |
2513 | ||
2514 | rc = secondary_ops->inode_follow_link(dentry,nameidata); | |
2515 | if (rc) | |
2516 | return rc; | |
2517 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2518 | } | |
2519 | ||
2520 | static int selinux_inode_permission(struct inode *inode, int mask, | |
2521 | struct nameidata *nd) | |
2522 | { | |
2523 | int rc; | |
2524 | ||
2525 | rc = secondary_ops->inode_permission(inode, mask, nd); | |
2526 | if (rc) | |
2527 | return rc; | |
2528 | ||
2529 | if (!mask) { | |
2530 | /* No permission to check. Existence test. */ | |
2531 | return 0; | |
2532 | } | |
2533 | ||
2534 | return inode_has_perm(current, inode, | |
2535 | file_mask_to_av(inode->i_mode, mask), NULL); | |
2536 | } | |
2537 | ||
2538 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2539 | { | |
2540 | int rc; | |
2541 | ||
2542 | rc = secondary_ops->inode_setattr(dentry, iattr); | |
2543 | if (rc) | |
2544 | return rc; | |
2545 | ||
2546 | if (iattr->ia_valid & ATTR_FORCE) | |
2547 | return 0; | |
2548 | ||
2549 | if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
2550 | ATTR_ATIME_SET | ATTR_MTIME_SET)) | |
2551 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2552 | ||
2553 | return dentry_has_perm(current, NULL, dentry, FILE__WRITE); | |
2554 | } | |
2555 | ||
2556 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2557 | { | |
2558 | return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); | |
2559 | } | |
2560 | ||
b5376771 SH |
2561 | static int selinux_inode_setotherxattr(struct dentry *dentry, char *name) |
2562 | { | |
2563 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
2564 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2565 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2566 | if (!capable(CAP_SETFCAP)) | |
2567 | return -EPERM; | |
2568 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2569 | /* A different attribute in the security namespace. | |
2570 | Restrict to administrator. */ | |
2571 | return -EPERM; | |
2572 | } | |
2573 | } | |
2574 | ||
2575 | /* Not an attribute we recognize, so just check the | |
2576 | ordinary setattr permission. */ | |
2577 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2578 | } | |
2579 | ||
1da177e4 LT |
2580 | static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) |
2581 | { | |
2582 | struct task_security_struct *tsec = current->security; | |
2583 | struct inode *inode = dentry->d_inode; | |
2584 | struct inode_security_struct *isec = inode->i_security; | |
2585 | struct superblock_security_struct *sbsec; | |
2586 | struct avc_audit_data ad; | |
2587 | u32 newsid; | |
2588 | int rc = 0; | |
2589 | ||
b5376771 SH |
2590 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2591 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2592 | |
2593 | sbsec = inode->i_sb->s_security; | |
2594 | if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) | |
2595 | return -EOPNOTSUPP; | |
2596 | ||
3bd858ab | 2597 | if (!is_owner_or_cap(inode)) |
1da177e4 LT |
2598 | return -EPERM; |
2599 | ||
2600 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
44707fdf | 2601 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
2602 | |
2603 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, | |
2604 | FILE__RELABELFROM, &ad); | |
2605 | if (rc) | |
2606 | return rc; | |
2607 | ||
2608 | rc = security_context_to_sid(value, size, &newsid); | |
2609 | if (rc) | |
2610 | return rc; | |
2611 | ||
2612 | rc = avc_has_perm(tsec->sid, newsid, isec->sclass, | |
2613 | FILE__RELABELTO, &ad); | |
2614 | if (rc) | |
2615 | return rc; | |
2616 | ||
2617 | rc = security_validate_transition(isec->sid, newsid, tsec->sid, | |
2618 | isec->sclass); | |
2619 | if (rc) | |
2620 | return rc; | |
2621 | ||
2622 | return avc_has_perm(newsid, | |
2623 | sbsec->sid, | |
2624 | SECCLASS_FILESYSTEM, | |
2625 | FILESYSTEM__ASSOCIATE, | |
2626 | &ad); | |
2627 | } | |
2628 | ||
2629 | static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, | |
2630 | void *value, size_t size, int flags) | |
2631 | { | |
2632 | struct inode *inode = dentry->d_inode; | |
2633 | struct inode_security_struct *isec = inode->i_security; | |
2634 | u32 newsid; | |
2635 | int rc; | |
2636 | ||
2637 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2638 | /* Not an attribute we recognize, so nothing to do. */ | |
2639 | return; | |
2640 | } | |
2641 | ||
2642 | rc = security_context_to_sid(value, size, &newsid); | |
2643 | if (rc) { | |
2644 | printk(KERN_WARNING "%s: unable to obtain SID for context " | |
2645 | "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); | |
2646 | return; | |
2647 | } | |
2648 | ||
2649 | isec->sid = newsid; | |
2650 | return; | |
2651 | } | |
2652 | ||
2653 | static int selinux_inode_getxattr (struct dentry *dentry, char *name) | |
2654 | { | |
1da177e4 LT |
2655 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); |
2656 | } | |
2657 | ||
2658 | static int selinux_inode_listxattr (struct dentry *dentry) | |
2659 | { | |
2660 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); | |
2661 | } | |
2662 | ||
2663 | static int selinux_inode_removexattr (struct dentry *dentry, char *name) | |
2664 | { | |
b5376771 SH |
2665 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2666 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2667 | |
2668 | /* No one is allowed to remove a SELinux security label. | |
2669 | You can change the label, but all data must be labeled. */ | |
2670 | return -EACCES; | |
2671 | } | |
2672 | ||
d381d8a9 JM |
2673 | /* |
2674 | * Copy the in-core inode security context value to the user. If the | |
2675 | * getxattr() prior to this succeeded, check to see if we need to | |
2676 | * canonicalize the value to be finally returned to the user. | |
2677 | * | |
2678 | * Permission check is handled by selinux_inode_getxattr hook. | |
2679 | */ | |
42492594 | 2680 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2681 | { |
42492594 DQ |
2682 | u32 size; |
2683 | int error; | |
2684 | char *context = NULL; | |
1da177e4 | 2685 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2686 | |
8c8570fb DK |
2687 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2688 | return -EOPNOTSUPP; | |
d381d8a9 | 2689 | |
42492594 DQ |
2690 | error = security_sid_to_context(isec->sid, &context, &size); |
2691 | if (error) | |
2692 | return error; | |
2693 | error = size; | |
2694 | if (alloc) { | |
2695 | *buffer = context; | |
2696 | goto out_nofree; | |
2697 | } | |
2698 | kfree(context); | |
2699 | out_nofree: | |
2700 | return error; | |
1da177e4 LT |
2701 | } |
2702 | ||
2703 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
2704 | const void *value, size_t size, int flags) | |
2705 | { | |
2706 | struct inode_security_struct *isec = inode->i_security; | |
2707 | u32 newsid; | |
2708 | int rc; | |
2709 | ||
2710 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2711 | return -EOPNOTSUPP; | |
2712 | ||
2713 | if (!value || !size) | |
2714 | return -EACCES; | |
2715 | ||
2716 | rc = security_context_to_sid((void*)value, size, &newsid); | |
2717 | if (rc) | |
2718 | return rc; | |
2719 | ||
2720 | isec->sid = newsid; | |
2721 | return 0; | |
2722 | } | |
2723 | ||
2724 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
2725 | { | |
2726 | const int len = sizeof(XATTR_NAME_SELINUX); | |
2727 | if (buffer && len <= buffer_size) | |
2728 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
2729 | return len; | |
2730 | } | |
2731 | ||
b5376771 SH |
2732 | static int selinux_inode_need_killpriv(struct dentry *dentry) |
2733 | { | |
2734 | return secondary_ops->inode_need_killpriv(dentry); | |
2735 | } | |
2736 | ||
2737 | static int selinux_inode_killpriv(struct dentry *dentry) | |
2738 | { | |
2739 | return secondary_ops->inode_killpriv(dentry); | |
2740 | } | |
2741 | ||
1da177e4 LT |
2742 | /* file security operations */ |
2743 | ||
788e7dd4 | 2744 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 2745 | { |
7420ed23 | 2746 | int rc; |
3d5ff529 | 2747 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2748 | |
2749 | if (!mask) { | |
2750 | /* No permission to check. Existence test. */ | |
2751 | return 0; | |
2752 | } | |
2753 | ||
2754 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
2755 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
2756 | mask |= MAY_APPEND; | |
2757 | ||
7420ed23 VY |
2758 | rc = file_has_perm(current, file, |
2759 | file_mask_to_av(inode->i_mode, mask)); | |
2760 | if (rc) | |
2761 | return rc; | |
2762 | ||
2763 | return selinux_netlbl_inode_permission(inode, mask); | |
1da177e4 LT |
2764 | } |
2765 | ||
788e7dd4 YN |
2766 | static int selinux_file_permission(struct file *file, int mask) |
2767 | { | |
2768 | struct inode *inode = file->f_path.dentry->d_inode; | |
2769 | struct task_security_struct *tsec = current->security; | |
2770 | struct file_security_struct *fsec = file->f_security; | |
2771 | struct inode_security_struct *isec = inode->i_security; | |
2772 | ||
2773 | if (!mask) { | |
2774 | /* No permission to check. Existence test. */ | |
2775 | return 0; | |
2776 | } | |
2777 | ||
2778 | if (tsec->sid == fsec->sid && fsec->isid == isec->sid | |
2779 | && fsec->pseqno == avc_policy_seqno()) | |
2780 | return selinux_netlbl_inode_permission(inode, mask); | |
2781 | ||
2782 | return selinux_revalidate_file_permission(file, mask); | |
2783 | } | |
2784 | ||
1da177e4 LT |
2785 | static int selinux_file_alloc_security(struct file *file) |
2786 | { | |
2787 | return file_alloc_security(file); | |
2788 | } | |
2789 | ||
2790 | static void selinux_file_free_security(struct file *file) | |
2791 | { | |
2792 | file_free_security(file); | |
2793 | } | |
2794 | ||
2795 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
2796 | unsigned long arg) | |
2797 | { | |
2798 | int error = 0; | |
2799 | ||
2800 | switch (cmd) { | |
2801 | case FIONREAD: | |
2802 | /* fall through */ | |
2803 | case FIBMAP: | |
2804 | /* fall through */ | |
2805 | case FIGETBSZ: | |
2806 | /* fall through */ | |
2807 | case EXT2_IOC_GETFLAGS: | |
2808 | /* fall through */ | |
2809 | case EXT2_IOC_GETVERSION: | |
2810 | error = file_has_perm(current, file, FILE__GETATTR); | |
2811 | break; | |
2812 | ||
2813 | case EXT2_IOC_SETFLAGS: | |
2814 | /* fall through */ | |
2815 | case EXT2_IOC_SETVERSION: | |
2816 | error = file_has_perm(current, file, FILE__SETATTR); | |
2817 | break; | |
2818 | ||
2819 | /* sys_ioctl() checks */ | |
2820 | case FIONBIO: | |
2821 | /* fall through */ | |
2822 | case FIOASYNC: | |
2823 | error = file_has_perm(current, file, 0); | |
2824 | break; | |
2825 | ||
2826 | case KDSKBENT: | |
2827 | case KDSKBSENT: | |
2828 | error = task_has_capability(current,CAP_SYS_TTY_CONFIG); | |
2829 | break; | |
2830 | ||
2831 | /* default case assumes that the command will go | |
2832 | * to the file's ioctl() function. | |
2833 | */ | |
2834 | default: | |
2835 | error = file_has_perm(current, file, FILE__IOCTL); | |
2836 | ||
2837 | } | |
2838 | return error; | |
2839 | } | |
2840 | ||
2841 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
2842 | { | |
2843 | #ifndef CONFIG_PPC32 | |
2844 | if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
2845 | /* | |
2846 | * We are making executable an anonymous mapping or a | |
2847 | * private file mapping that will also be writable. | |
2848 | * This has an additional check. | |
2849 | */ | |
2850 | int rc = task_has_perm(current, current, PROCESS__EXECMEM); | |
2851 | if (rc) | |
2852 | return rc; | |
2853 | } | |
2854 | #endif | |
2855 | ||
2856 | if (file) { | |
2857 | /* read access is always possible with a mapping */ | |
2858 | u32 av = FILE__READ; | |
2859 | ||
2860 | /* write access only matters if the mapping is shared */ | |
2861 | if (shared && (prot & PROT_WRITE)) | |
2862 | av |= FILE__WRITE; | |
2863 | ||
2864 | if (prot & PROT_EXEC) | |
2865 | av |= FILE__EXECUTE; | |
2866 | ||
2867 | return file_has_perm(current, file, av); | |
2868 | } | |
2869 | return 0; | |
2870 | } | |
2871 | ||
2872 | static int selinux_file_mmap(struct file *file, unsigned long reqprot, | |
ed032189 EP |
2873 | unsigned long prot, unsigned long flags, |
2874 | unsigned long addr, unsigned long addr_only) | |
1da177e4 | 2875 | { |
ed032189 EP |
2876 | int rc = 0; |
2877 | u32 sid = ((struct task_security_struct*)(current->security))->sid; | |
1da177e4 | 2878 | |
ed032189 EP |
2879 | if (addr < mmap_min_addr) |
2880 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, | |
2881 | MEMPROTECT__MMAP_ZERO, NULL); | |
2882 | if (rc || addr_only) | |
1da177e4 LT |
2883 | return rc; |
2884 | ||
2885 | if (selinux_checkreqprot) | |
2886 | prot = reqprot; | |
2887 | ||
2888 | return file_map_prot_check(file, prot, | |
2889 | (flags & MAP_TYPE) == MAP_SHARED); | |
2890 | } | |
2891 | ||
2892 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
2893 | unsigned long reqprot, | |
2894 | unsigned long prot) | |
2895 | { | |
2896 | int rc; | |
2897 | ||
2898 | rc = secondary_ops->file_mprotect(vma, reqprot, prot); | |
2899 | if (rc) | |
2900 | return rc; | |
2901 | ||
2902 | if (selinux_checkreqprot) | |
2903 | prot = reqprot; | |
2904 | ||
2905 | #ifndef CONFIG_PPC32 | |
db4c9641 SS |
2906 | if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
2907 | rc = 0; | |
2908 | if (vma->vm_start >= vma->vm_mm->start_brk && | |
2909 | vma->vm_end <= vma->vm_mm->brk) { | |
2910 | rc = task_has_perm(current, current, | |
2911 | PROCESS__EXECHEAP); | |
2912 | } else if (!vma->vm_file && | |
2913 | vma->vm_start <= vma->vm_mm->start_stack && | |
2914 | vma->vm_end >= vma->vm_mm->start_stack) { | |
2915 | rc = task_has_perm(current, current, PROCESS__EXECSTACK); | |
2916 | } else if (vma->vm_file && vma->anon_vma) { | |
2917 | /* | |
2918 | * We are making executable a file mapping that has | |
2919 | * had some COW done. Since pages might have been | |
2920 | * written, check ability to execute the possibly | |
2921 | * modified content. This typically should only | |
2922 | * occur for text relocations. | |
2923 | */ | |
2924 | rc = file_has_perm(current, vma->vm_file, | |
2925 | FILE__EXECMOD); | |
2926 | } | |