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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->task = task; |
165 | tsec->osid = tsec->sid = tsec->ptrace_sid = SECINITSID_UNLABELED; | |
166 | task->security = tsec; | |
167 | ||
168 | return 0; | |
169 | } | |
170 | ||
171 | static void task_free_security(struct task_struct *task) | |
172 | { | |
173 | struct task_security_struct *tsec = task->security; | |
1da177e4 LT |
174 | task->security = NULL; |
175 | kfree(tsec); | |
176 | } | |
177 | ||
178 | static int inode_alloc_security(struct inode *inode) | |
179 | { | |
180 | struct task_security_struct *tsec = current->security; | |
181 | struct inode_security_struct *isec; | |
182 | ||
c3762229 | 183 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_KERNEL); |
1da177e4 LT |
184 | if (!isec) |
185 | return -ENOMEM; | |
186 | ||
23970741 | 187 | mutex_init(&isec->lock); |
1da177e4 | 188 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
189 | isec->inode = inode; |
190 | isec->sid = SECINITSID_UNLABELED; | |
191 | isec->sclass = SECCLASS_FILE; | |
9ac49d22 | 192 | isec->task_sid = tsec->sid; |
1da177e4 LT |
193 | inode->i_security = isec; |
194 | ||
195 | return 0; | |
196 | } | |
197 | ||
198 | static void inode_free_security(struct inode *inode) | |
199 | { | |
200 | struct inode_security_struct *isec = inode->i_security; | |
201 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
202 | ||
1da177e4 LT |
203 | spin_lock(&sbsec->isec_lock); |
204 | if (!list_empty(&isec->list)) | |
205 | list_del_init(&isec->list); | |
206 | spin_unlock(&sbsec->isec_lock); | |
207 | ||
208 | inode->i_security = NULL; | |
7cae7e26 | 209 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
210 | } |
211 | ||
212 | static int file_alloc_security(struct file *file) | |
213 | { | |
214 | struct task_security_struct *tsec = current->security; | |
215 | struct file_security_struct *fsec; | |
216 | ||
26d2a4be | 217 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
218 | if (!fsec) |
219 | return -ENOMEM; | |
220 | ||
1da177e4 | 221 | fsec->file = file; |
9ac49d22 SS |
222 | fsec->sid = tsec->sid; |
223 | fsec->fown_sid = tsec->sid; | |
1da177e4 LT |
224 | file->f_security = fsec; |
225 | ||
226 | return 0; | |
227 | } | |
228 | ||
229 | static void file_free_security(struct file *file) | |
230 | { | |
231 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
232 | file->f_security = NULL; |
233 | kfree(fsec); | |
234 | } | |
235 | ||
236 | static int superblock_alloc_security(struct super_block *sb) | |
237 | { | |
238 | struct superblock_security_struct *sbsec; | |
239 | ||
89d155ef | 240 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
241 | if (!sbsec) |
242 | return -ENOMEM; | |
243 | ||
bc7e982b | 244 | mutex_init(&sbsec->lock); |
1da177e4 LT |
245 | INIT_LIST_HEAD(&sbsec->list); |
246 | INIT_LIST_HEAD(&sbsec->isec_head); | |
247 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
248 | sbsec->sb = sb; |
249 | sbsec->sid = SECINITSID_UNLABELED; | |
250 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 251 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
252 | sb->s_security = sbsec; |
253 | ||
254 | return 0; | |
255 | } | |
256 | ||
257 | static void superblock_free_security(struct super_block *sb) | |
258 | { | |
259 | struct superblock_security_struct *sbsec = sb->s_security; | |
260 | ||
1da177e4 LT |
261 | spin_lock(&sb_security_lock); |
262 | if (!list_empty(&sbsec->list)) | |
263 | list_del_init(&sbsec->list); | |
264 | spin_unlock(&sb_security_lock); | |
265 | ||
266 | sb->s_security = NULL; | |
267 | kfree(sbsec); | |
268 | } | |
269 | ||
7d877f3b | 270 | static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
1da177e4 LT |
271 | { |
272 | struct sk_security_struct *ssec; | |
273 | ||
89d155ef | 274 | ssec = kzalloc(sizeof(*ssec), priority); |
1da177e4 LT |
275 | if (!ssec) |
276 | return -ENOMEM; | |
277 | ||
1da177e4 LT |
278 | ssec->sk = sk; |
279 | ssec->peer_sid = SECINITSID_UNLABELED; | |
892c141e | 280 | ssec->sid = SECINITSID_UNLABELED; |
1da177e4 LT |
281 | sk->sk_security = ssec; |
282 | ||
99f59ed0 PM |
283 | selinux_netlbl_sk_security_init(ssec, family); |
284 | ||
1da177e4 LT |
285 | return 0; |
286 | } | |
287 | ||
288 | static void sk_free_security(struct sock *sk) | |
289 | { | |
290 | struct sk_security_struct *ssec = sk->sk_security; | |
291 | ||
1da177e4 LT |
292 | sk->sk_security = NULL; |
293 | kfree(ssec); | |
294 | } | |
1da177e4 LT |
295 | |
296 | /* The security server must be initialized before | |
297 | any labeling or access decisions can be provided. */ | |
298 | extern int ss_initialized; | |
299 | ||
300 | /* The file system's label must be initialized prior to use. */ | |
301 | ||
302 | static char *labeling_behaviors[6] = { | |
303 | "uses xattr", | |
304 | "uses transition SIDs", | |
305 | "uses task SIDs", | |
306 | "uses genfs_contexts", | |
307 | "not configured for labeling", | |
308 | "uses mountpoint labeling", | |
309 | }; | |
310 | ||
311 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
312 | ||
313 | static inline int inode_doinit(struct inode *inode) | |
314 | { | |
315 | return inode_doinit_with_dentry(inode, NULL); | |
316 | } | |
317 | ||
318 | enum { | |
31e87930 | 319 | Opt_error = -1, |
1da177e4 LT |
320 | Opt_context = 1, |
321 | Opt_fscontext = 2, | |
c9180a57 EP |
322 | Opt_defcontext = 3, |
323 | Opt_rootcontext = 4, | |
1da177e4 LT |
324 | }; |
325 | ||
326 | static match_table_t tokens = { | |
327 | {Opt_context, "context=%s"}, | |
328 | {Opt_fscontext, "fscontext=%s"}, | |
329 | {Opt_defcontext, "defcontext=%s"}, | |
0808925e | 330 | {Opt_rootcontext, "rootcontext=%s"}, |
31e87930 | 331 | {Opt_error, NULL}, |
1da177e4 LT |
332 | }; |
333 | ||
334 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
335 | ||
c312feb2 EP |
336 | static int may_context_mount_sb_relabel(u32 sid, |
337 | struct superblock_security_struct *sbsec, | |
338 | struct task_security_struct *tsec) | |
339 | { | |
340 | int rc; | |
341 | ||
342 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
343 | FILESYSTEM__RELABELFROM, NULL); | |
344 | if (rc) | |
345 | return rc; | |
346 | ||
347 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
348 | FILESYSTEM__RELABELTO, NULL); | |
349 | return rc; | |
350 | } | |
351 | ||
0808925e EP |
352 | static int may_context_mount_inode_relabel(u32 sid, |
353 | struct superblock_security_struct *sbsec, | |
354 | struct task_security_struct *tsec) | |
355 | { | |
356 | int rc; | |
357 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
358 | FILESYSTEM__RELABELFROM, NULL); | |
359 | if (rc) | |
360 | return rc; | |
361 | ||
362 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
363 | FILESYSTEM__ASSOCIATE, NULL); | |
364 | return rc; | |
365 | } | |
366 | ||
c9180a57 | 367 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 368 | { |
1da177e4 | 369 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
370 | struct dentry *root = sb->s_root; |
371 | struct inode *root_inode = root->d_inode; | |
372 | int rc = 0; | |
1da177e4 | 373 | |
c9180a57 EP |
374 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
375 | /* Make sure that the xattr handler exists and that no | |
376 | error other than -ENODATA is returned by getxattr on | |
377 | the root directory. -ENODATA is ok, as this may be | |
378 | the first boot of the SELinux kernel before we have | |
379 | assigned xattr values to the filesystem. */ | |
380 | if (!root_inode->i_op->getxattr) { | |
381 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
382 | "xattr support\n", sb->s_id, sb->s_type->name); | |
383 | rc = -EOPNOTSUPP; | |
384 | goto out; | |
385 | } | |
386 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
387 | if (rc < 0 && rc != -ENODATA) { | |
388 | if (rc == -EOPNOTSUPP) | |
389 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
390 | "%s) has no security xattr handler\n", | |
391 | sb->s_id, sb->s_type->name); | |
392 | else | |
393 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
394 | "%s) getxattr errno %d\n", sb->s_id, | |
395 | sb->s_type->name, -rc); | |
396 | goto out; | |
397 | } | |
398 | } | |
1da177e4 | 399 | |
c9180a57 | 400 | sbsec->initialized = 1; |
1da177e4 | 401 | |
c9180a57 EP |
402 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
403 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
404 | sb->s_id, sb->s_type->name); | |
405 | else | |
406 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", | |
407 | sb->s_id, sb->s_type->name, | |
408 | labeling_behaviors[sbsec->behavior-1]); | |
1da177e4 | 409 | |
c9180a57 EP |
410 | /* Initialize the root inode. */ |
411 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 412 | |
c9180a57 EP |
413 | /* Initialize any other inodes associated with the superblock, e.g. |
414 | inodes created prior to initial policy load or inodes created | |
415 | during get_sb by a pseudo filesystem that directly | |
416 | populates itself. */ | |
417 | spin_lock(&sbsec->isec_lock); | |
418 | next_inode: | |
419 | if (!list_empty(&sbsec->isec_head)) { | |
420 | struct inode_security_struct *isec = | |
421 | list_entry(sbsec->isec_head.next, | |
422 | struct inode_security_struct, list); | |
423 | struct inode *inode = isec->inode; | |
424 | spin_unlock(&sbsec->isec_lock); | |
425 | inode = igrab(inode); | |
426 | if (inode) { | |
427 | if (!IS_PRIVATE(inode)) | |
428 | inode_doinit(inode); | |
429 | iput(inode); | |
430 | } | |
431 | spin_lock(&sbsec->isec_lock); | |
432 | list_del_init(&isec->list); | |
433 | goto next_inode; | |
434 | } | |
435 | spin_unlock(&sbsec->isec_lock); | |
436 | out: | |
437 | return rc; | |
438 | } | |
1da177e4 | 439 | |
c9180a57 EP |
440 | /* |
441 | * This function should allow an FS to ask what it's mount security | |
442 | * options were so it can use those later for submounts, displaying | |
443 | * mount options, or whatever. | |
444 | */ | |
445 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
446 | char ***mount_options, int **mnt_opts_flags, | |
447 | int *num_opts) | |
448 | { | |
449 | int rc = 0, i; | |
450 | struct superblock_security_struct *sbsec = sb->s_security; | |
451 | char *context = NULL; | |
452 | u32 len; | |
453 | char tmp; | |
1da177e4 | 454 | |
c9180a57 EP |
455 | *num_opts = 0; |
456 | *mount_options = NULL; | |
457 | *mnt_opts_flags = NULL; | |
1da177e4 | 458 | |
c9180a57 EP |
459 | if (!sbsec->initialized) |
460 | return -EINVAL; | |
1da177e4 | 461 | |
c9180a57 EP |
462 | if (!ss_initialized) |
463 | return -EINVAL; | |
1da177e4 | 464 | |
c9180a57 EP |
465 | /* |
466 | * if we ever use sbsec flags for anything other than tracking mount | |
467 | * settings this is going to need a mask | |
468 | */ | |
469 | tmp = sbsec->flags; | |
470 | /* count the number of mount options for this sb */ | |
471 | for (i = 0; i < 8; i++) { | |
472 | if (tmp & 0x01) | |
473 | (*num_opts)++; | |
474 | tmp >>= 1; | |
475 | } | |
1da177e4 | 476 | |
c9180a57 EP |
477 | *mount_options = kcalloc(*num_opts, sizeof(char *), GFP_ATOMIC); |
478 | if (!*mount_options) { | |
479 | rc = -ENOMEM; | |
480 | goto out_free; | |
481 | } | |
1da177e4 | 482 | |
c9180a57 EP |
483 | *mnt_opts_flags = kcalloc(*num_opts, sizeof(int), GFP_ATOMIC); |
484 | if (!*mnt_opts_flags) { | |
485 | rc = -ENOMEM; | |
486 | goto out_free; | |
487 | } | |
1da177e4 | 488 | |
c9180a57 EP |
489 | i = 0; |
490 | if (sbsec->flags & FSCONTEXT_MNT) { | |
491 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
492 | if (rc) | |
493 | goto out_free; | |
494 | (*mount_options)[i] = context; | |
495 | (*mnt_opts_flags)[i++] = FSCONTEXT_MNT; | |
496 | } | |
497 | if (sbsec->flags & CONTEXT_MNT) { | |
498 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
499 | if (rc) | |
500 | goto out_free; | |
501 | (*mount_options)[i] = context; | |
502 | (*mnt_opts_flags)[i++] = CONTEXT_MNT; | |
503 | } | |
504 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
505 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
506 | if (rc) | |
507 | goto out_free; | |
508 | (*mount_options)[i] = context; | |
509 | (*mnt_opts_flags)[i++] = DEFCONTEXT_MNT; | |
510 | } | |
511 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
512 | struct inode *root = sbsec->sb->s_root->d_inode; | |
513 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 514 | |
c9180a57 EP |
515 | rc = security_sid_to_context(isec->sid, &context, &len); |
516 | if (rc) | |
517 | goto out_free; | |
518 | (*mount_options)[i] = context; | |
519 | (*mnt_opts_flags)[i++] = ROOTCONTEXT_MNT; | |
520 | } | |
1da177e4 | 521 | |
c9180a57 | 522 | BUG_ON(i != *num_opts); |
1da177e4 | 523 | |
c9180a57 EP |
524 | return 0; |
525 | ||
526 | out_free: | |
527 | /* don't leak context string if security_sid_to_context had an error */ | |
528 | if (*mount_options && i) | |
529 | for (; i > 0; i--) | |
530 | kfree((*mount_options)[i-1]); | |
531 | kfree(*mount_options); | |
532 | *mount_options = NULL; | |
533 | kfree(*mnt_opts_flags); | |
534 | *mnt_opts_flags = NULL; | |
535 | *num_opts = 0; | |
536 | return rc; | |
537 | } | |
1da177e4 | 538 | |
c9180a57 EP |
539 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
540 | u32 old_sid, u32 new_sid) | |
541 | { | |
542 | /* check if the old mount command had the same options */ | |
543 | if (sbsec->initialized) | |
544 | if (!(sbsec->flags & flag) || | |
545 | (old_sid != new_sid)) | |
546 | return 1; | |
547 | ||
548 | /* check if we were passed the same options twice, | |
549 | * aka someone passed context=a,context=b | |
550 | */ | |
551 | if (!sbsec->initialized) | |
552 | if (sbsec->flags & flag) | |
553 | return 1; | |
554 | return 0; | |
555 | } | |
556 | /* | |
557 | * Allow filesystems with binary mount data to explicitly set mount point | |
558 | * labeling information. | |
559 | */ | |
374ea019 AB |
560 | static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options, |
561 | int *flags, int num_opts) | |
c9180a57 EP |
562 | { |
563 | int rc = 0, i; | |
564 | struct task_security_struct *tsec = current->security; | |
565 | struct superblock_security_struct *sbsec = sb->s_security; | |
566 | const char *name = sb->s_type->name; | |
567 | struct inode *inode = sbsec->sb->s_root->d_inode; | |
568 | struct inode_security_struct *root_isec = inode->i_security; | |
569 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; | |
570 | u32 defcontext_sid = 0; | |
571 | ||
572 | mutex_lock(&sbsec->lock); | |
573 | ||
574 | if (!ss_initialized) { | |
575 | if (!num_opts) { | |
576 | /* Defer initialization until selinux_complete_init, | |
577 | after the initial policy is loaded and the security | |
578 | server is ready to handle calls. */ | |
579 | spin_lock(&sb_security_lock); | |
580 | if (list_empty(&sbsec->list)) | |
581 | list_add(&sbsec->list, &superblock_security_head); | |
582 | spin_unlock(&sb_security_lock); | |
583 | goto out; | |
584 | } | |
585 | rc = -EINVAL; | |
586 | printk(KERN_WARNING "Unable to set superblock options before " | |
587 | "the security server is initialized\n"); | |
1da177e4 | 588 | goto out; |
c9180a57 | 589 | } |
1da177e4 | 590 | |
c9180a57 EP |
591 | /* |
592 | * parse the mount options, check if they are valid sids. | |
593 | * also check if someone is trying to mount the same sb more | |
594 | * than once with different security options. | |
595 | */ | |
596 | for (i = 0; i < num_opts; i++) { | |
597 | u32 sid; | |
598 | rc = security_context_to_sid(mount_options[i], | |
599 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
600 | if (rc) { |
601 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
602 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
c9180a57 EP |
603 | mount_options[i], sb->s_id, name, rc); |
604 | goto out; | |
605 | } | |
606 | switch (flags[i]) { | |
607 | case FSCONTEXT_MNT: | |
608 | fscontext_sid = sid; | |
609 | ||
610 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
611 | fscontext_sid)) | |
612 | goto out_double_mount; | |
613 | ||
614 | sbsec->flags |= FSCONTEXT_MNT; | |
615 | break; | |
616 | case CONTEXT_MNT: | |
617 | context_sid = sid; | |
618 | ||
619 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
620 | context_sid)) | |
621 | goto out_double_mount; | |
622 | ||
623 | sbsec->flags |= CONTEXT_MNT; | |
624 | break; | |
625 | case ROOTCONTEXT_MNT: | |
626 | rootcontext_sid = sid; | |
627 | ||
628 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
629 | rootcontext_sid)) | |
630 | goto out_double_mount; | |
631 | ||
632 | sbsec->flags |= ROOTCONTEXT_MNT; | |
633 | ||
634 | break; | |
635 | case DEFCONTEXT_MNT: | |
636 | defcontext_sid = sid; | |
637 | ||
638 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
639 | defcontext_sid)) | |
640 | goto out_double_mount; | |
641 | ||
642 | sbsec->flags |= DEFCONTEXT_MNT; | |
643 | ||
644 | break; | |
645 | default: | |
646 | rc = -EINVAL; | |
647 | goto out; | |
1da177e4 | 648 | } |
c9180a57 EP |
649 | } |
650 | ||
651 | if (sbsec->initialized) { | |
652 | /* previously mounted with options, but not on this attempt? */ | |
653 | if (sbsec->flags && !num_opts) | |
654 | goto out_double_mount; | |
655 | rc = 0; | |
656 | goto out; | |
657 | } | |
658 | ||
659 | if (strcmp(sb->s_type->name, "proc") == 0) | |
660 | sbsec->proc = 1; | |
661 | ||
662 | /* Determine the labeling behavior to use for this filesystem type. */ | |
663 | rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid); | |
664 | if (rc) { | |
665 | printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", | |
666 | __FUNCTION__, sb->s_type->name, rc); | |
667 | goto out; | |
668 | } | |
1da177e4 | 669 | |
c9180a57 EP |
670 | /* sets the context of the superblock for the fs being mounted. */ |
671 | if (fscontext_sid) { | |
672 | ||
673 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec); | |
1da177e4 | 674 | if (rc) |
c9180a57 | 675 | goto out; |
1da177e4 | 676 | |
c9180a57 | 677 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
678 | } |
679 | ||
680 | /* | |
681 | * Switch to using mount point labeling behavior. | |
682 | * sets the label used on all file below the mountpoint, and will set | |
683 | * the superblock context if not already set. | |
684 | */ | |
c9180a57 EP |
685 | if (context_sid) { |
686 | if (!fscontext_sid) { | |
687 | rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec); | |
b04ea3ce | 688 | if (rc) |
c9180a57 EP |
689 | goto out; |
690 | sbsec->sid = context_sid; | |
b04ea3ce | 691 | } else { |
c9180a57 | 692 | rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec); |
b04ea3ce | 693 | if (rc) |
c9180a57 | 694 | goto out; |
b04ea3ce | 695 | } |
c9180a57 EP |
696 | if (!rootcontext_sid) |
697 | rootcontext_sid = context_sid; | |
1da177e4 | 698 | |
c9180a57 | 699 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 700 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
701 | } |
702 | ||
c9180a57 EP |
703 | if (rootcontext_sid) { |
704 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec); | |
0808925e | 705 | if (rc) |
c9180a57 | 706 | goto out; |
0808925e | 707 | |
c9180a57 EP |
708 | root_isec->sid = rootcontext_sid; |
709 | root_isec->initialized = 1; | |
0808925e EP |
710 | } |
711 | ||
c9180a57 EP |
712 | if (defcontext_sid) { |
713 | if (sbsec->behavior != SECURITY_FS_USE_XATTR) { | |
714 | rc = -EINVAL; | |
715 | printk(KERN_WARNING "SELinux: defcontext option is " | |
716 | "invalid for this filesystem type\n"); | |
717 | goto out; | |
1da177e4 LT |
718 | } |
719 | ||
c9180a57 EP |
720 | if (defcontext_sid != sbsec->def_sid) { |
721 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
722 | sbsec, tsec); | |
723 | if (rc) | |
724 | goto out; | |
725 | } | |
1da177e4 | 726 | |
c9180a57 | 727 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
728 | } |
729 | ||
c9180a57 | 730 | rc = sb_finish_set_opts(sb); |
1da177e4 | 731 | out: |
c9180a57 | 732 | mutex_unlock(&sbsec->lock); |
1da177e4 | 733 | return rc; |
c9180a57 EP |
734 | out_double_mount: |
735 | rc = -EINVAL; | |
736 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
737 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
738 | goto out; | |
1da177e4 LT |
739 | } |
740 | ||
c9180a57 EP |
741 | static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
742 | struct super_block *newsb) | |
1da177e4 | 743 | { |
c9180a57 EP |
744 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
745 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 746 | |
c9180a57 EP |
747 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
748 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
749 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 750 | |
c9180a57 EP |
751 | /* we can't error, we can't save the info, this shouldn't get called |
752 | * this early in the boot process. */ | |
753 | BUG_ON(!ss_initialized); | |
754 | ||
755 | /* this might go away sometime down the line if there is a new user | |
756 | * of clone, but for now, nfs better not get here... */ | |
757 | BUG_ON(newsbsec->initialized); | |
758 | ||
759 | /* how can we clone if the old one wasn't set up?? */ | |
760 | BUG_ON(!oldsbsec->initialized); | |
761 | ||
762 | mutex_lock(&newsbsec->lock); | |
763 | ||
764 | newsbsec->flags = oldsbsec->flags; | |
765 | ||
766 | newsbsec->sid = oldsbsec->sid; | |
767 | newsbsec->def_sid = oldsbsec->def_sid; | |
768 | newsbsec->behavior = oldsbsec->behavior; | |
769 | ||
770 | if (set_context) { | |
771 | u32 sid = oldsbsec->mntpoint_sid; | |
772 | ||
773 | if (!set_fscontext) | |
774 | newsbsec->sid = sid; | |
775 | if (!set_rootcontext) { | |
776 | struct inode *newinode = newsb->s_root->d_inode; | |
777 | struct inode_security_struct *newisec = newinode->i_security; | |
778 | newisec->sid = sid; | |
779 | } | |
780 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 781 | } |
c9180a57 EP |
782 | if (set_rootcontext) { |
783 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
784 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
785 | struct inode *newinode = newsb->s_root->d_inode; | |
786 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 787 | |
c9180a57 | 788 | newisec->sid = oldisec->sid; |
1da177e4 LT |
789 | } |
790 | ||
c9180a57 EP |
791 | sb_finish_set_opts(newsb); |
792 | mutex_unlock(&newsbsec->lock); | |
793 | } | |
794 | ||
795 | /* | |
796 | * string mount options parsing and call set the sbsec | |
797 | */ | |
798 | static int superblock_doinit(struct super_block *sb, void *data) | |
799 | { | |
800 | char *context = NULL, *defcontext = NULL; | |
801 | char *fscontext = NULL, *rootcontext = NULL; | |
802 | int rc = 0; | |
803 | char *p, *options = data; | |
804 | /* selinux only know about a fixed number of mount options */ | |
805 | char *mnt_opts[NUM_SEL_MNT_OPTS]; | |
806 | int mnt_opts_flags[NUM_SEL_MNT_OPTS], num_mnt_opts = 0; | |
807 | ||
808 | if (!data) | |
1da177e4 LT |
809 | goto out; |
810 | ||
c9180a57 EP |
811 | /* with the nfs patch this will become a goto out; */ |
812 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) { | |
813 | const char *name = sb->s_type->name; | |
814 | /* NFS we understand. */ | |
815 | if (!strcmp(name, "nfs")) { | |
816 | struct nfs_mount_data *d = data; | |
817 | ||
818 | if (d->version != NFS_MOUNT_VERSION) | |
819 | goto out; | |
820 | ||
821 | if (d->context[0]) { | |
822 | context = kstrdup(d->context, GFP_KERNEL); | |
823 | if (!context) { | |
824 | rc = -ENOMEM; | |
825 | goto out; | |
826 | } | |
827 | } | |
828 | goto build_flags; | |
829 | } else | |
1da177e4 | 830 | goto out; |
1da177e4 LT |
831 | } |
832 | ||
c9180a57 EP |
833 | /* Standard string-based options. */ |
834 | while ((p = strsep(&options, "|")) != NULL) { | |
835 | int token; | |
836 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 837 | |
c9180a57 EP |
838 | if (!*p) |
839 | continue; | |
1da177e4 | 840 | |
c9180a57 | 841 | token = match_token(p, tokens, args); |
1da177e4 | 842 | |
c9180a57 EP |
843 | switch (token) { |
844 | case Opt_context: | |
845 | if (context || defcontext) { | |
846 | rc = -EINVAL; | |
847 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
848 | goto out_err; | |
849 | } | |
850 | context = match_strdup(&args[0]); | |
851 | if (!context) { | |
852 | rc = -ENOMEM; | |
853 | goto out_err; | |
854 | } | |
855 | break; | |
856 | ||
857 | case Opt_fscontext: | |
858 | if (fscontext) { | |
859 | rc = -EINVAL; | |
860 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
861 | goto out_err; | |
862 | } | |
863 | fscontext = match_strdup(&args[0]); | |
864 | if (!fscontext) { | |
865 | rc = -ENOMEM; | |
866 | goto out_err; | |
867 | } | |
868 | break; | |
869 | ||
870 | case Opt_rootcontext: | |
871 | if (rootcontext) { | |
872 | rc = -EINVAL; | |
873 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
874 | goto out_err; | |
875 | } | |
876 | rootcontext = match_strdup(&args[0]); | |
877 | if (!rootcontext) { | |
878 | rc = -ENOMEM; | |
879 | goto out_err; | |
880 | } | |
881 | break; | |
882 | ||
883 | case Opt_defcontext: | |
884 | if (context || defcontext) { | |
885 | rc = -EINVAL; | |
886 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
887 | goto out_err; | |
888 | } | |
889 | defcontext = match_strdup(&args[0]); | |
890 | if (!defcontext) { | |
891 | rc = -ENOMEM; | |
892 | goto out_err; | |
893 | } | |
894 | break; | |
895 | ||
896 | default: | |
897 | rc = -EINVAL; | |
898 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
899 | goto out_err; | |
1da177e4 | 900 | |
1da177e4 | 901 | } |
1da177e4 | 902 | } |
c9180a57 EP |
903 | |
904 | build_flags: | |
905 | if (fscontext) { | |
906 | mnt_opts[num_mnt_opts] = fscontext; | |
907 | mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
908 | } | |
909 | if (context) { | |
910 | mnt_opts[num_mnt_opts] = context; | |
911 | mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
912 | } | |
913 | if (rootcontext) { | |
914 | mnt_opts[num_mnt_opts] = rootcontext; | |
915 | mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
916 | } | |
917 | if (defcontext) { | |
918 | mnt_opts[num_mnt_opts] = defcontext; | |
919 | mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
920 | } | |
921 | ||
1da177e4 | 922 | out: |
c9180a57 EP |
923 | rc = selinux_set_mnt_opts(sb, mnt_opts, mnt_opts_flags, num_mnt_opts); |
924 | out_err: | |
925 | kfree(context); | |
926 | kfree(defcontext); | |
927 | kfree(fscontext); | |
928 | kfree(rootcontext); | |
1da177e4 LT |
929 | return rc; |
930 | } | |
931 | ||
932 | static inline u16 inode_mode_to_security_class(umode_t mode) | |
933 | { | |
934 | switch (mode & S_IFMT) { | |
935 | case S_IFSOCK: | |
936 | return SECCLASS_SOCK_FILE; | |
937 | case S_IFLNK: | |
938 | return SECCLASS_LNK_FILE; | |
939 | case S_IFREG: | |
940 | return SECCLASS_FILE; | |
941 | case S_IFBLK: | |
942 | return SECCLASS_BLK_FILE; | |
943 | case S_IFDIR: | |
944 | return SECCLASS_DIR; | |
945 | case S_IFCHR: | |
946 | return SECCLASS_CHR_FILE; | |
947 | case S_IFIFO: | |
948 | return SECCLASS_FIFO_FILE; | |
949 | ||
950 | } | |
951 | ||
952 | return SECCLASS_FILE; | |
953 | } | |
954 | ||
13402580 JM |
955 | static inline int default_protocol_stream(int protocol) |
956 | { | |
957 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
958 | } | |
959 | ||
960 | static inline int default_protocol_dgram(int protocol) | |
961 | { | |
962 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
963 | } | |
964 | ||
1da177e4 LT |
965 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
966 | { | |
967 | switch (family) { | |
968 | case PF_UNIX: | |
969 | switch (type) { | |
970 | case SOCK_STREAM: | |
971 | case SOCK_SEQPACKET: | |
972 | return SECCLASS_UNIX_STREAM_SOCKET; | |
973 | case SOCK_DGRAM: | |
974 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
975 | } | |
976 | break; | |
977 | case PF_INET: | |
978 | case PF_INET6: | |
979 | switch (type) { | |
980 | case SOCK_STREAM: | |
13402580 JM |
981 | if (default_protocol_stream(protocol)) |
982 | return SECCLASS_TCP_SOCKET; | |
983 | else | |
984 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 985 | case SOCK_DGRAM: |
13402580 JM |
986 | if (default_protocol_dgram(protocol)) |
987 | return SECCLASS_UDP_SOCKET; | |
988 | else | |
989 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
990 | case SOCK_DCCP: |
991 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 992 | default: |
1da177e4 LT |
993 | return SECCLASS_RAWIP_SOCKET; |
994 | } | |
995 | break; | |
996 | case PF_NETLINK: | |
997 | switch (protocol) { | |
998 | case NETLINK_ROUTE: | |
999 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1000 | case NETLINK_FIREWALL: | |
1001 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
216efaaa | 1002 | case NETLINK_INET_DIAG: |
1da177e4 LT |
1003 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1004 | case NETLINK_NFLOG: | |
1005 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1006 | case NETLINK_XFRM: | |
1007 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1008 | case NETLINK_SELINUX: | |
1009 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1010 | case NETLINK_AUDIT: | |
1011 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1012 | case NETLINK_IP6_FW: | |
1013 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1014 | case NETLINK_DNRTMSG: | |
1015 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1016 | case NETLINK_KOBJECT_UEVENT: |
1017 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1018 | default: |
1019 | return SECCLASS_NETLINK_SOCKET; | |
1020 | } | |
1021 | case PF_PACKET: | |
1022 | return SECCLASS_PACKET_SOCKET; | |
1023 | case PF_KEY: | |
1024 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1025 | case PF_APPLETALK: |
1026 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1027 | } |
1028 | ||
1029 | return SECCLASS_SOCKET; | |
1030 | } | |
1031 | ||
1032 | #ifdef CONFIG_PROC_FS | |
1033 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1034 | u16 tclass, | |
1035 | u32 *sid) | |
1036 | { | |
1037 | int buflen, rc; | |
1038 | char *buffer, *path, *end; | |
1039 | ||
1040 | buffer = (char*)__get_free_page(GFP_KERNEL); | |
1041 | if (!buffer) | |
1042 | return -ENOMEM; | |
1043 | ||
1044 | buflen = PAGE_SIZE; | |
1045 | end = buffer+buflen; | |
1046 | *--end = '\0'; | |
1047 | buflen--; | |
1048 | path = end-1; | |
1049 | *path = '/'; | |
1050 | while (de && de != de->parent) { | |
1051 | buflen -= de->namelen + 1; | |
1052 | if (buflen < 0) | |
1053 | break; | |
1054 | end -= de->namelen; | |
1055 | memcpy(end, de->name, de->namelen); | |
1056 | *--end = '/'; | |
1057 | path = end; | |
1058 | de = de->parent; | |
1059 | } | |
1060 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1061 | free_page((unsigned long)buffer); | |
1062 | return rc; | |
1063 | } | |
1064 | #else | |
1065 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1066 | u16 tclass, | |
1067 | u32 *sid) | |
1068 | { | |
1069 | return -EINVAL; | |
1070 | } | |
1071 | #endif | |
1072 | ||
1073 | /* The inode's security attributes must be initialized before first use. */ | |
1074 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1075 | { | |
1076 | struct superblock_security_struct *sbsec = NULL; | |
1077 | struct inode_security_struct *isec = inode->i_security; | |
1078 | u32 sid; | |
1079 | struct dentry *dentry; | |
1080 | #define INITCONTEXTLEN 255 | |
1081 | char *context = NULL; | |
1082 | unsigned len = 0; | |
1083 | int rc = 0; | |
1da177e4 LT |
1084 | |
1085 | if (isec->initialized) | |
1086 | goto out; | |
1087 | ||
23970741 | 1088 | mutex_lock(&isec->lock); |
1da177e4 | 1089 | if (isec->initialized) |
23970741 | 1090 | goto out_unlock; |
1da177e4 LT |
1091 | |
1092 | sbsec = inode->i_sb->s_security; | |
1093 | if (!sbsec->initialized) { | |
1094 | /* Defer initialization until selinux_complete_init, | |
1095 | after the initial policy is loaded and the security | |
1096 | server is ready to handle calls. */ | |
1097 | spin_lock(&sbsec->isec_lock); | |
1098 | if (list_empty(&isec->list)) | |
1099 | list_add(&isec->list, &sbsec->isec_head); | |
1100 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1101 | goto out_unlock; |
1da177e4 LT |
1102 | } |
1103 | ||
1104 | switch (sbsec->behavior) { | |
1105 | case SECURITY_FS_USE_XATTR: | |
1106 | if (!inode->i_op->getxattr) { | |
1107 | isec->sid = sbsec->def_sid; | |
1108 | break; | |
1109 | } | |
1110 | ||
1111 | /* Need a dentry, since the xattr API requires one. | |
1112 | Life would be simpler if we could just pass the inode. */ | |
1113 | if (opt_dentry) { | |
1114 | /* Called from d_instantiate or d_splice_alias. */ | |
1115 | dentry = dget(opt_dentry); | |
1116 | } else { | |
1117 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1118 | dentry = d_find_alias(inode); | |
1119 | } | |
1120 | if (!dentry) { | |
1121 | printk(KERN_WARNING "%s: no dentry for dev=%s " | |
1122 | "ino=%ld\n", __FUNCTION__, inode->i_sb->s_id, | |
1123 | inode->i_ino); | |
23970741 | 1124 | goto out_unlock; |
1da177e4 LT |
1125 | } |
1126 | ||
1127 | len = INITCONTEXTLEN; | |
1128 | context = kmalloc(len, GFP_KERNEL); | |
1129 | if (!context) { | |
1130 | rc = -ENOMEM; | |
1131 | dput(dentry); | |
23970741 | 1132 | goto out_unlock; |
1da177e4 LT |
1133 | } |
1134 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1135 | context, len); | |
1136 | if (rc == -ERANGE) { | |
1137 | /* Need a larger buffer. Query for the right size. */ | |
1138 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1139 | NULL, 0); | |
1140 | if (rc < 0) { | |
1141 | dput(dentry); | |
23970741 | 1142 | goto out_unlock; |
1da177e4 LT |
1143 | } |
1144 | kfree(context); | |
1145 | len = rc; | |
1146 | context = kmalloc(len, GFP_KERNEL); | |
1147 | if (!context) { | |
1148 | rc = -ENOMEM; | |
1149 | dput(dentry); | |
23970741 | 1150 | goto out_unlock; |
1da177e4 LT |
1151 | } |
1152 | rc = inode->i_op->getxattr(dentry, | |
1153 | XATTR_NAME_SELINUX, | |
1154 | context, len); | |
1155 | } | |
1156 | dput(dentry); | |
1157 | if (rc < 0) { | |
1158 | if (rc != -ENODATA) { | |
1159 | printk(KERN_WARNING "%s: getxattr returned " | |
1160 | "%d for dev=%s ino=%ld\n", __FUNCTION__, | |
1161 | -rc, inode->i_sb->s_id, inode->i_ino); | |
1162 | kfree(context); | |
23970741 | 1163 | goto out_unlock; |
1da177e4 LT |
1164 | } |
1165 | /* Map ENODATA to the default file SID */ | |
1166 | sid = sbsec->def_sid; | |
1167 | rc = 0; | |
1168 | } else { | |
f5c1d5b2 JM |
1169 | rc = security_context_to_sid_default(context, rc, &sid, |
1170 | sbsec->def_sid); | |
1da177e4 LT |
1171 | if (rc) { |
1172 | printk(KERN_WARNING "%s: context_to_sid(%s) " | |
1173 | "returned %d for dev=%s ino=%ld\n", | |
1174 | __FUNCTION__, context, -rc, | |
1175 | inode->i_sb->s_id, inode->i_ino); | |
1176 | kfree(context); | |
1177 | /* Leave with the unlabeled SID */ | |
1178 | rc = 0; | |
1179 | break; | |
1180 | } | |
1181 | } | |
1182 | kfree(context); | |
1183 | isec->sid = sid; | |
1184 | break; | |
1185 | case SECURITY_FS_USE_TASK: | |
1186 | isec->sid = isec->task_sid; | |
1187 | break; | |
1188 | case SECURITY_FS_USE_TRANS: | |
1189 | /* Default to the fs SID. */ | |
1190 | isec->sid = sbsec->sid; | |
1191 | ||
1192 | /* Try to obtain a transition SID. */ | |
1193 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1194 | rc = security_transition_sid(isec->task_sid, | |
1195 | sbsec->sid, | |
1196 | isec->sclass, | |
1197 | &sid); | |
1198 | if (rc) | |
23970741 | 1199 | goto out_unlock; |
1da177e4 LT |
1200 | isec->sid = sid; |
1201 | break; | |
c312feb2 EP |
1202 | case SECURITY_FS_USE_MNTPOINT: |
1203 | isec->sid = sbsec->mntpoint_sid; | |
1204 | break; | |
1da177e4 | 1205 | default: |
c312feb2 | 1206 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1207 | isec->sid = sbsec->sid; |
1208 | ||
1209 | if (sbsec->proc) { | |
1210 | struct proc_inode *proci = PROC_I(inode); | |
1211 | if (proci->pde) { | |
1212 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1213 | rc = selinux_proc_get_sid(proci->pde, | |
1214 | isec->sclass, | |
1215 | &sid); | |
1216 | if (rc) | |
23970741 | 1217 | goto out_unlock; |
1da177e4 LT |
1218 | isec->sid = sid; |
1219 | } | |
1220 | } | |
1221 | break; | |
1222 | } | |
1223 | ||
1224 | isec->initialized = 1; | |
1225 | ||
23970741 EP |
1226 | out_unlock: |
1227 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1228 | out: |
1229 | if (isec->sclass == SECCLASS_FILE) | |
1230 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1231 | return rc; |
1232 | } | |
1233 | ||
1234 | /* Convert a Linux signal to an access vector. */ | |
1235 | static inline u32 signal_to_av(int sig) | |
1236 | { | |
1237 | u32 perm = 0; | |
1238 | ||
1239 | switch (sig) { | |
1240 | case SIGCHLD: | |
1241 | /* Commonly granted from child to parent. */ | |
1242 | perm = PROCESS__SIGCHLD; | |
1243 | break; | |
1244 | case SIGKILL: | |
1245 | /* Cannot be caught or ignored */ | |
1246 | perm = PROCESS__SIGKILL; | |
1247 | break; | |
1248 | case SIGSTOP: | |
1249 | /* Cannot be caught or ignored */ | |
1250 | perm = PROCESS__SIGSTOP; | |
1251 | break; | |
1252 | default: | |
1253 | /* All other signals. */ | |
1254 | perm = PROCESS__SIGNAL; | |
1255 | break; | |
1256 | } | |
1257 | ||
1258 | return perm; | |
1259 | } | |
1260 | ||
1261 | /* Check permission betweeen a pair of tasks, e.g. signal checks, | |
1262 | fork check, ptrace check, etc. */ | |
1263 | static int task_has_perm(struct task_struct *tsk1, | |
1264 | struct task_struct *tsk2, | |
1265 | u32 perms) | |
1266 | { | |
1267 | struct task_security_struct *tsec1, *tsec2; | |
1268 | ||
1269 | tsec1 = tsk1->security; | |
1270 | tsec2 = tsk2->security; | |
1271 | return avc_has_perm(tsec1->sid, tsec2->sid, | |
1272 | SECCLASS_PROCESS, perms, NULL); | |
1273 | } | |
1274 | ||
b68e418c SS |
1275 | #if CAP_LAST_CAP > 63 |
1276 | #error Fix SELinux to handle capabilities > 63. | |
1277 | #endif | |
1278 | ||
1da177e4 LT |
1279 | /* Check whether a task is allowed to use a capability. */ |
1280 | static int task_has_capability(struct task_struct *tsk, | |
1281 | int cap) | |
1282 | { | |
1283 | struct task_security_struct *tsec; | |
1284 | struct avc_audit_data ad; | |
b68e418c SS |
1285 | u16 sclass; |
1286 | u32 av = CAP_TO_MASK(cap); | |
1da177e4 LT |
1287 | |
1288 | tsec = tsk->security; | |
1289 | ||
1290 | AVC_AUDIT_DATA_INIT(&ad,CAP); | |
1291 | ad.tsk = tsk; | |
1292 | ad.u.cap = cap; | |
1293 | ||
b68e418c SS |
1294 | switch (CAP_TO_INDEX(cap)) { |
1295 | case 0: | |
1296 | sclass = SECCLASS_CAPABILITY; | |
1297 | break; | |
1298 | case 1: | |
1299 | sclass = SECCLASS_CAPABILITY2; | |
1300 | break; | |
1301 | default: | |
1302 | printk(KERN_ERR | |
1303 | "SELinux: out of range capability %d\n", cap); | |
1304 | BUG(); | |
1305 | } | |
1306 | return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad); | |
1da177e4 LT |
1307 | } |
1308 | ||
1309 | /* Check whether a task is allowed to use a system operation. */ | |
1310 | static int task_has_system(struct task_struct *tsk, | |
1311 | u32 perms) | |
1312 | { | |
1313 | struct task_security_struct *tsec; | |
1314 | ||
1315 | tsec = tsk->security; | |
1316 | ||
1317 | return avc_has_perm(tsec->sid, SECINITSID_KERNEL, | |
1318 | SECCLASS_SYSTEM, perms, NULL); | |
1319 | } | |
1320 | ||
1321 | /* Check whether a task has a particular permission to an inode. | |
1322 | The 'adp' parameter is optional and allows other audit | |
1323 | data to be passed (e.g. the dentry). */ | |
1324 | static int inode_has_perm(struct task_struct *tsk, | |
1325 | struct inode *inode, | |
1326 | u32 perms, | |
1327 | struct avc_audit_data *adp) | |
1328 | { | |
1329 | struct task_security_struct *tsec; | |
1330 | struct inode_security_struct *isec; | |
1331 | struct avc_audit_data ad; | |
1332 | ||
bbaca6c2 SS |
1333 | if (unlikely (IS_PRIVATE (inode))) |
1334 | return 0; | |
1335 | ||
1da177e4 LT |
1336 | tsec = tsk->security; |
1337 | isec = inode->i_security; | |
1338 | ||
1339 | if (!adp) { | |
1340 | adp = &ad; | |
1341 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1342 | ad.u.fs.inode = inode; | |
1343 | } | |
1344 | ||
1345 | return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); | |
1346 | } | |
1347 | ||
1348 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1349 | the dentry to help the auditing code to more easily generate the | |
1350 | pathname if needed. */ | |
1351 | static inline int dentry_has_perm(struct task_struct *tsk, | |
1352 | struct vfsmount *mnt, | |
1353 | struct dentry *dentry, | |
1354 | u32 av) | |
1355 | { | |
1356 | struct inode *inode = dentry->d_inode; | |
1357 | struct avc_audit_data ad; | |
1358 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
1359 | ad.u.fs.mnt = mnt; | |
1360 | ad.u.fs.dentry = dentry; | |
1361 | return inode_has_perm(tsk, inode, av, &ad); | |
1362 | } | |
1363 | ||
1364 | /* Check whether a task can use an open file descriptor to | |
1365 | access an inode in a given way. Check access to the | |
1366 | descriptor itself, and then use dentry_has_perm to | |
1367 | check a particular permission to the file. | |
1368 | Access to the descriptor is implicitly granted if it | |
1369 | has the same SID as the process. If av is zero, then | |
1370 | access to the file is not checked, e.g. for cases | |
1371 | where only the descriptor is affected like seek. */ | |
858119e1 | 1372 | static int file_has_perm(struct task_struct *tsk, |
1da177e4 LT |
1373 | struct file *file, |
1374 | u32 av) | |
1375 | { | |
1376 | struct task_security_struct *tsec = tsk->security; | |
1377 | struct file_security_struct *fsec = file->f_security; | |
3d5ff529 JS |
1378 | struct vfsmount *mnt = file->f_path.mnt; |
1379 | struct dentry *dentry = file->f_path.dentry; | |
1da177e4 LT |
1380 | struct inode *inode = dentry->d_inode; |
1381 | struct avc_audit_data ad; | |
1382 | int rc; | |
1383 | ||
1384 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1385 | ad.u.fs.mnt = mnt; | |
1386 | ad.u.fs.dentry = dentry; | |
1387 | ||
1388 | if (tsec->sid != fsec->sid) { | |
1389 | rc = avc_has_perm(tsec->sid, fsec->sid, | |
1390 | SECCLASS_FD, | |
1391 | FD__USE, | |
1392 | &ad); | |
1393 | if (rc) | |
1394 | return rc; | |
1395 | } | |
1396 | ||
1397 | /* av is zero if only checking access to the descriptor. */ | |
1398 | if (av) | |
1399 | return inode_has_perm(tsk, inode, av, &ad); | |
1400 | ||
1401 | return 0; | |
1402 | } | |
1403 | ||
1404 | /* Check whether a task can create a file. */ | |
1405 | static int may_create(struct inode *dir, | |
1406 | struct dentry *dentry, | |
1407 | u16 tclass) | |
1408 | { | |
1409 | struct task_security_struct *tsec; | |
1410 | struct inode_security_struct *dsec; | |
1411 | struct superblock_security_struct *sbsec; | |
1412 | u32 newsid; | |
1413 | struct avc_audit_data ad; | |
1414 | int rc; | |
1415 | ||
1416 | tsec = current->security; | |
1417 | dsec = dir->i_security; | |
1418 | sbsec = dir->i_sb->s_security; | |
1419 | ||
1420 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1421 | ad.u.fs.dentry = dentry; | |
1422 | ||
1423 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, | |
1424 | DIR__ADD_NAME | DIR__SEARCH, | |
1425 | &ad); | |
1426 | if (rc) | |
1427 | return rc; | |
1428 | ||
1429 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
1430 | newsid = tsec->create_sid; | |
1431 | } else { | |
1432 | rc = security_transition_sid(tsec->sid, dsec->sid, tclass, | |
1433 | &newsid); | |
1434 | if (rc) | |
1435 | return rc; | |
1436 | } | |
1437 | ||
1438 | rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); | |
1439 | if (rc) | |
1440 | return rc; | |
1441 | ||
1442 | return avc_has_perm(newsid, sbsec->sid, | |
1443 | SECCLASS_FILESYSTEM, | |
1444 | FILESYSTEM__ASSOCIATE, &ad); | |
1445 | } | |
1446 | ||
4eb582cf ML |
1447 | /* Check whether a task can create a key. */ |
1448 | static int may_create_key(u32 ksid, | |
1449 | struct task_struct *ctx) | |
1450 | { | |
1451 | struct task_security_struct *tsec; | |
1452 | ||
1453 | tsec = ctx->security; | |
1454 | ||
1455 | return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); | |
1456 | } | |
1457 | ||
1da177e4 LT |
1458 | #define MAY_LINK 0 |
1459 | #define MAY_UNLINK 1 | |
1460 | #define MAY_RMDIR 2 | |
1461 | ||
1462 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1463 | static int may_link(struct inode *dir, | |
1464 | struct dentry *dentry, | |
1465 | int kind) | |
1466 | ||
1467 | { | |
1468 | struct task_security_struct *tsec; | |
1469 | struct inode_security_struct *dsec, *isec; | |
1470 | struct avc_audit_data ad; | |
1471 | u32 av; | |
1472 | int rc; | |
1473 | ||
1474 | tsec = current->security; | |
1475 | dsec = dir->i_security; | |
1476 | isec = dentry->d_inode->i_security; | |
1477 | ||
1478 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1479 | ad.u.fs.dentry = dentry; | |
1480 | ||
1481 | av = DIR__SEARCH; | |
1482 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
1483 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1484 | if (rc) | |
1485 | return rc; | |
1486 | ||
1487 | switch (kind) { | |
1488 | case MAY_LINK: | |
1489 | av = FILE__LINK; | |
1490 | break; | |
1491 | case MAY_UNLINK: | |
1492 | av = FILE__UNLINK; | |
1493 | break; | |
1494 | case MAY_RMDIR: | |
1495 | av = DIR__RMDIR; | |
1496 | break; | |
1497 | default: | |
1498 | printk(KERN_WARNING "may_link: unrecognized kind %d\n", kind); | |
1499 | return 0; | |
1500 | } | |
1501 | ||
1502 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); | |
1503 | return rc; | |
1504 | } | |
1505 | ||
1506 | static inline int may_rename(struct inode *old_dir, | |
1507 | struct dentry *old_dentry, | |
1508 | struct inode *new_dir, | |
1509 | struct dentry *new_dentry) | |
1510 | { | |
1511 | struct task_security_struct *tsec; | |
1512 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; | |
1513 | struct avc_audit_data ad; | |
1514 | u32 av; | |
1515 | int old_is_dir, new_is_dir; | |
1516 | int rc; | |
1517 | ||
1518 | tsec = current->security; | |
1519 | old_dsec = old_dir->i_security; | |
1520 | old_isec = old_dentry->d_inode->i_security; | |
1521 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1522 | new_dsec = new_dir->i_security; | |
1523 | ||
1524 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1525 | ||
1526 | ad.u.fs.dentry = old_dentry; | |
1527 | rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, | |
1528 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); | |
1529 | if (rc) | |
1530 | return rc; | |
1531 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1532 | old_isec->sclass, FILE__RENAME, &ad); | |
1533 | if (rc) | |
1534 | return rc; | |
1535 | if (old_is_dir && new_dir != old_dir) { | |
1536 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1537 | old_isec->sclass, DIR__REPARENT, &ad); | |
1538 | if (rc) | |
1539 | return rc; | |
1540 | } | |
1541 | ||
1542 | ad.u.fs.dentry = new_dentry; | |
1543 | av = DIR__ADD_NAME | DIR__SEARCH; | |
1544 | if (new_dentry->d_inode) | |
1545 | av |= DIR__REMOVE_NAME; | |
1546 | rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1547 | if (rc) | |
1548 | return rc; | |
1549 | if (new_dentry->d_inode) { | |
1550 | new_isec = new_dentry->d_inode->i_security; | |
1551 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
1552 | rc = avc_has_perm(tsec->sid, new_isec->sid, | |
1553 | new_isec->sclass, | |
1554 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1555 | if (rc) | |
1556 | return rc; | |
1557 | } | |
1558 | ||
1559 | return 0; | |
1560 | } | |
1561 | ||
1562 | /* Check whether a task can perform a filesystem operation. */ | |
1563 | static int superblock_has_perm(struct task_struct *tsk, | |
1564 | struct super_block *sb, | |
1565 | u32 perms, | |
1566 | struct avc_audit_data *ad) | |
1567 | { | |
1568 | struct task_security_struct *tsec; | |
1569 | struct superblock_security_struct *sbsec; | |
1570 | ||
1571 | tsec = tsk->security; | |
1572 | sbsec = sb->s_security; | |
1573 | return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
1574 | perms, ad); | |
1575 | } | |
1576 | ||
1577 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1578 | static inline u32 file_mask_to_av(int mode, int mask) | |
1579 | { | |
1580 | u32 av = 0; | |
1581 | ||
1582 | if ((mode & S_IFMT) != S_IFDIR) { | |
1583 | if (mask & MAY_EXEC) | |
1584 | av |= FILE__EXECUTE; | |
1585 | if (mask & MAY_READ) | |
1586 | av |= FILE__READ; | |
1587 | ||
1588 | if (mask & MAY_APPEND) | |
1589 | av |= FILE__APPEND; | |
1590 | else if (mask & MAY_WRITE) | |
1591 | av |= FILE__WRITE; | |
1592 | ||
1593 | } else { | |
1594 | if (mask & MAY_EXEC) | |
1595 | av |= DIR__SEARCH; | |
1596 | if (mask & MAY_WRITE) | |
1597 | av |= DIR__WRITE; | |
1598 | if (mask & MAY_READ) | |
1599 | av |= DIR__READ; | |
1600 | } | |
1601 | ||
1602 | return av; | |
1603 | } | |
1604 | ||
1605 | /* Convert a Linux file to an access vector. */ | |
1606 | static inline u32 file_to_av(struct file *file) | |
1607 | { | |
1608 | u32 av = 0; | |
1609 | ||
1610 | if (file->f_mode & FMODE_READ) | |
1611 | av |= FILE__READ; | |
1612 | if (file->f_mode & FMODE_WRITE) { | |
1613 | if (file->f_flags & O_APPEND) | |
1614 | av |= FILE__APPEND; | |
1615 | else | |
1616 | av |= FILE__WRITE; | |
1617 | } | |
1618 | ||
1619 | return av; | |
1620 | } | |
1621 | ||
1da177e4 LT |
1622 | /* Hook functions begin here. */ |
1623 | ||
1624 | static int selinux_ptrace(struct task_struct *parent, struct task_struct *child) | |
1625 | { | |
1626 | struct task_security_struct *psec = parent->security; | |
1627 | struct task_security_struct *csec = child->security; | |
1628 | int rc; | |
1629 | ||
1630 | rc = secondary_ops->ptrace(parent,child); | |
1631 | if (rc) | |
1632 | return rc; | |
1633 | ||
1634 | rc = task_has_perm(parent, child, PROCESS__PTRACE); | |
1635 | /* Save the SID of the tracing process for later use in apply_creds. */ | |
341c2d80 | 1636 | if (!(child->ptrace & PT_PTRACED) && !rc) |
1da177e4 LT |
1637 | csec->ptrace_sid = psec->sid; |
1638 | return rc; | |
1639 | } | |
1640 | ||
1641 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
1642 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1643 | { | |
1644 | int error; | |
1645 | ||
1646 | error = task_has_perm(current, target, PROCESS__GETCAP); | |
1647 | if (error) | |
1648 | return error; | |
1649 | ||
1650 | return secondary_ops->capget(target, effective, inheritable, permitted); | |
1651 | } | |
1652 | ||
1653 | static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, | |
1654 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1655 | { | |
1656 | int error; | |
1657 | ||
1658 | error = secondary_ops->capset_check(target, effective, inheritable, permitted); | |
1659 | if (error) | |
1660 | return error; | |
1661 | ||
1662 | return task_has_perm(current, target, PROCESS__SETCAP); | |
1663 | } | |
1664 | ||
1665 | static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, | |
1666 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
1667 | { | |
1668 | secondary_ops->capset_set(target, effective, inheritable, permitted); | |
1669 | } | |
1670 | ||
1671 | static int selinux_capable(struct task_struct *tsk, int cap) | |
1672 | { | |
1673 | int rc; | |
1674 | ||
1675 | rc = secondary_ops->capable(tsk, cap); | |
1676 | if (rc) | |
1677 | return rc; | |
1678 | ||
1679 | return task_has_capability(tsk,cap); | |
1680 | } | |
1681 | ||
3fbfa981 EB |
1682 | static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) |
1683 | { | |
1684 | int buflen, rc; | |
1685 | char *buffer, *path, *end; | |
1686 | ||
1687 | rc = -ENOMEM; | |
1688 | buffer = (char*)__get_free_page(GFP_KERNEL); | |
1689 | if (!buffer) | |
1690 | goto out; | |
1691 | ||
1692 | buflen = PAGE_SIZE; | |
1693 | end = buffer+buflen; | |
1694 | *--end = '\0'; | |
1695 | buflen--; | |
1696 | path = end-1; | |
1697 | *path = '/'; | |
1698 | while (table) { | |
1699 | const char *name = table->procname; | |
1700 | size_t namelen = strlen(name); | |
1701 | buflen -= namelen + 1; | |
1702 | if (buflen < 0) | |
1703 | goto out_free; | |
1704 | end -= namelen; | |
1705 | memcpy(end, name, namelen); | |
1706 | *--end = '/'; | |
1707 | path = end; | |
1708 | table = table->parent; | |
1709 | } | |
b599fdfd EB |
1710 | buflen -= 4; |
1711 | if (buflen < 0) | |
1712 | goto out_free; | |
1713 | end -= 4; | |
1714 | memcpy(end, "/sys", 4); | |
1715 | path = end; | |
3fbfa981 EB |
1716 | rc = security_genfs_sid("proc", path, tclass, sid); |
1717 | out_free: | |
1718 | free_page((unsigned long)buffer); | |
1719 | out: | |
1720 | return rc; | |
1721 | } | |
1722 | ||
1da177e4 LT |
1723 | static int selinux_sysctl(ctl_table *table, int op) |
1724 | { | |
1725 | int error = 0; | |
1726 | u32 av; | |
1727 | struct task_security_struct *tsec; | |
1728 | u32 tsid; | |
1729 | int rc; | |
1730 | ||
1731 | rc = secondary_ops->sysctl(table, op); | |
1732 | if (rc) | |
1733 | return rc; | |
1734 | ||
1735 | tsec = current->security; | |
1736 | ||
3fbfa981 EB |
1737 | rc = selinux_sysctl_get_sid(table, (op == 0001) ? |
1738 | SECCLASS_DIR : SECCLASS_FILE, &tsid); | |
1da177e4 LT |
1739 | if (rc) { |
1740 | /* Default to the well-defined sysctl SID. */ | |
1741 | tsid = SECINITSID_SYSCTL; | |
1742 | } | |
1743 | ||
1744 | /* The op values are "defined" in sysctl.c, thereby creating | |
1745 | * a bad coupling between this module and sysctl.c */ | |
1746 | if(op == 001) { | |
1747 | error = avc_has_perm(tsec->sid, tsid, | |
1748 | SECCLASS_DIR, DIR__SEARCH, NULL); | |
1749 | } else { | |
1750 | av = 0; | |
1751 | if (op & 004) | |
1752 | av |= FILE__READ; | |
1753 | if (op & 002) | |
1754 | av |= FILE__WRITE; | |
1755 | if (av) | |
1756 | error = avc_has_perm(tsec->sid, tsid, | |
1757 | SECCLASS_FILE, av, NULL); | |
1758 | } | |
1759 | ||
1760 | return error; | |
1761 | } | |
1762 | ||
1763 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
1764 | { | |
1765 | int rc = 0; | |
1766 | ||
1767 | if (!sb) | |
1768 | return 0; | |
1769 | ||
1770 | switch (cmds) { | |
1771 | case Q_SYNC: | |
1772 | case Q_QUOTAON: | |
1773 | case Q_QUOTAOFF: | |
1774 | case Q_SETINFO: | |
1775 | case Q_SETQUOTA: | |
1776 | rc = superblock_has_perm(current, | |
1777 | sb, | |
1778 | FILESYSTEM__QUOTAMOD, NULL); | |
1779 | break; | |
1780 | case Q_GETFMT: | |
1781 | case Q_GETINFO: | |
1782 | case Q_GETQUOTA: | |
1783 | rc = superblock_has_perm(current, | |
1784 | sb, | |
1785 | FILESYSTEM__QUOTAGET, NULL); | |
1786 | break; | |
1787 | default: | |
1788 | rc = 0; /* let the kernel handle invalid cmds */ | |
1789 | break; | |
1790 | } | |
1791 | return rc; | |
1792 | } | |
1793 | ||
1794 | static int selinux_quota_on(struct dentry *dentry) | |
1795 | { | |
1796 | return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); | |
1797 | } | |
1798 | ||
1799 | static int selinux_syslog(int type) | |
1800 | { | |
1801 | int rc; | |
1802 | ||
1803 | rc = secondary_ops->syslog(type); | |
1804 | if (rc) | |
1805 | return rc; | |
1806 | ||
1807 | switch (type) { | |
1808 | case 3: /* Read last kernel messages */ | |
1809 | case 10: /* Return size of the log buffer */ | |
1810 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); | |
1811 | break; | |
1812 | case 6: /* Disable logging to console */ | |
1813 | case 7: /* Enable logging to console */ | |
1814 | case 8: /* Set level of messages printed to console */ | |
1815 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); | |
1816 | break; | |
1817 | case 0: /* Close log */ | |
1818 | case 1: /* Open log */ | |
1819 | case 2: /* Read from log */ | |
1820 | case 4: /* Read/clear last kernel messages */ | |
1821 | case 5: /* Clear ring buffer */ | |
1822 | default: | |
1823 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
1824 | break; | |
1825 | } | |
1826 | return rc; | |
1827 | } | |
1828 | ||
1829 | /* | |
1830 | * Check that a process has enough memory to allocate a new virtual | |
1831 | * mapping. 0 means there is enough memory for the allocation to | |
1832 | * succeed and -ENOMEM implies there is not. | |
1833 | * | |
1834 | * Note that secondary_ops->capable and task_has_perm_noaudit return 0 | |
1835 | * if the capability is granted, but __vm_enough_memory requires 1 if | |
1836 | * the capability is granted. | |
1837 | * | |
1838 | * Do not audit the selinux permission check, as this is applied to all | |
1839 | * processes that allocate mappings. | |
1840 | */ | |
34b4e4aa | 1841 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
1842 | { |
1843 | int rc, cap_sys_admin = 0; | |
1844 | struct task_security_struct *tsec = current->security; | |
1845 | ||
1846 | rc = secondary_ops->capable(current, CAP_SYS_ADMIN); | |
1847 | if (rc == 0) | |
1848 | rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, | |
2c3c05db SS |
1849 | SECCLASS_CAPABILITY, |
1850 | CAP_TO_MASK(CAP_SYS_ADMIN), | |
1851 | 0, | |
1852 | NULL); | |
1da177e4 LT |
1853 | |
1854 | if (rc == 0) | |
1855 | cap_sys_admin = 1; | |
1856 | ||
34b4e4aa | 1857 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
1858 | } |
1859 | ||
1860 | /* binprm security operations */ | |
1861 | ||
1862 | static int selinux_bprm_alloc_security(struct linux_binprm *bprm) | |
1863 | { | |
1864 | struct bprm_security_struct *bsec; | |
1865 | ||
89d155ef | 1866 | bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); |
1da177e4 LT |
1867 | if (!bsec) |
1868 | return -ENOMEM; | |
1869 | ||
1da177e4 LT |
1870 | bsec->bprm = bprm; |
1871 | bsec->sid = SECINITSID_UNLABELED; | |
1872 | bsec->set = 0; | |
1873 | ||
1874 | bprm->security = bsec; | |
1875 | return 0; | |
1876 | } | |
1877 | ||
1878 | static int selinux_bprm_set_security(struct linux_binprm *bprm) | |
1879 | { | |
1880 | struct task_security_struct *tsec; | |
3d5ff529 | 1881 | struct inode *inode = bprm->file->f_path.dentry->d_inode; |
1da177e4 LT |
1882 | struct inode_security_struct *isec; |
1883 | struct bprm_security_struct *bsec; | |
1884 | u32 newsid; | |
1885 | struct avc_audit_data ad; | |
1886 | int rc; | |
1887 | ||
1888 | rc = secondary_ops->bprm_set_security(bprm); | |
1889 | if (rc) | |
1890 | return rc; | |
1891 | ||
1892 | bsec = bprm->security; | |
1893 | ||
1894 | if (bsec->set) | |
1895 | return 0; | |
1896 | ||
1897 | tsec = current->security; | |
1898 | isec = inode->i_security; | |
1899 | ||
1900 | /* Default to the current task SID. */ | |
1901 | bsec->sid = tsec->sid; | |
1902 | ||
28eba5bf | 1903 | /* Reset fs, key, and sock SIDs on execve. */ |
1da177e4 | 1904 | tsec->create_sid = 0; |
28eba5bf | 1905 | tsec->keycreate_sid = 0; |
42c3e03e | 1906 | tsec->sockcreate_sid = 0; |
1da177e4 LT |
1907 | |
1908 | if (tsec->exec_sid) { | |
1909 | newsid = tsec->exec_sid; | |
1910 | /* Reset exec SID on execve. */ | |
1911 | tsec->exec_sid = 0; | |
1912 | } else { | |
1913 | /* Check for a default transition on this program. */ | |
1914 | rc = security_transition_sid(tsec->sid, isec->sid, | |
1915 | SECCLASS_PROCESS, &newsid); | |
1916 | if (rc) | |
1917 | return rc; | |
1918 | } | |
1919 | ||
1920 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
3d5ff529 JS |
1921 | ad.u.fs.mnt = bprm->file->f_path.mnt; |
1922 | ad.u.fs.dentry = bprm->file->f_path.dentry; | |
1da177e4 | 1923 | |
3d5ff529 | 1924 | if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
1da177e4 LT |
1925 | newsid = tsec->sid; |
1926 | ||
1927 | if (tsec->sid == newsid) { | |
1928 | rc = avc_has_perm(tsec->sid, isec->sid, | |
1929 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); | |
1930 | if (rc) | |
1931 | return rc; | |
1932 | } else { | |
1933 | /* Check permissions for the transition. */ | |
1934 | rc = avc_has_perm(tsec->sid, newsid, | |
1935 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); | |
1936 | if (rc) | |
1937 | return rc; | |
1938 | ||
1939 | rc = avc_has_perm(newsid, isec->sid, | |
1940 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); | |
1941 | if (rc) | |
1942 | return rc; | |
1943 | ||
1944 | /* Clear any possibly unsafe personality bits on exec: */ | |
1945 | current->personality &= ~PER_CLEAR_ON_SETID; | |
1946 | ||
1947 | /* Set the security field to the new SID. */ | |
1948 | bsec->sid = newsid; | |
1949 | } | |
1950 | ||
1951 | bsec->set = 1; | |
1952 | return 0; | |
1953 | } | |
1954 | ||
1955 | static int selinux_bprm_check_security (struct linux_binprm *bprm) | |
1956 | { | |
1957 | return secondary_ops->bprm_check_security(bprm); | |
1958 | } | |
1959 | ||
1960 | ||
1961 | static int selinux_bprm_secureexec (struct linux_binprm *bprm) | |
1962 | { | |
1963 | struct task_security_struct *tsec = current->security; | |
1964 | int atsecure = 0; | |
1965 | ||
1966 | if (tsec->osid != tsec->sid) { | |
1967 | /* Enable secure mode for SIDs transitions unless | |
1968 | the noatsecure permission is granted between | |
1969 | the two SIDs, i.e. ahp returns 0. */ | |
1970 | atsecure = avc_has_perm(tsec->osid, tsec->sid, | |
1971 | SECCLASS_PROCESS, | |
1972 | PROCESS__NOATSECURE, NULL); | |
1973 | } | |
1974 | ||
1975 | return (atsecure || secondary_ops->bprm_secureexec(bprm)); | |
1976 | } | |
1977 | ||
1978 | static void selinux_bprm_free_security(struct linux_binprm *bprm) | |
1979 | { | |
9a5f04bf | 1980 | kfree(bprm->security); |
1da177e4 | 1981 | bprm->security = NULL; |
1da177e4 LT |
1982 | } |
1983 | ||
1984 | extern struct vfsmount *selinuxfs_mount; | |
1985 | extern struct dentry *selinux_null; | |
1986 | ||
1987 | /* Derived from fs/exec.c:flush_old_files. */ | |
1988 | static inline void flush_unauthorized_files(struct files_struct * files) | |
1989 | { | |
1990 | struct avc_audit_data ad; | |
1991 | struct file *file, *devnull = NULL; | |
b20c8122 | 1992 | struct tty_struct *tty; |
badf1662 | 1993 | struct fdtable *fdt; |
1da177e4 | 1994 | long j = -1; |
24ec839c | 1995 | int drop_tty = 0; |
1da177e4 | 1996 | |
b20c8122 | 1997 | mutex_lock(&tty_mutex); |
24ec839c | 1998 | tty = get_current_tty(); |
1da177e4 LT |
1999 | if (tty) { |
2000 | file_list_lock(); | |
2f512016 | 2001 | file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); |
1da177e4 LT |
2002 | if (file) { |
2003 | /* Revalidate access to controlling tty. | |
2004 | Use inode_has_perm on the tty inode directly rather | |
2005 | than using file_has_perm, as this particular open | |
2006 | file may belong to another process and we are only | |
2007 | interested in the inode-based check here. */ | |
3d5ff529 | 2008 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2009 | if (inode_has_perm(current, inode, |
2010 | FILE__READ | FILE__WRITE, NULL)) { | |
24ec839c | 2011 | drop_tty = 1; |
1da177e4 LT |
2012 | } |
2013 | } | |
2014 | file_list_unlock(); | |
2015 | } | |
b20c8122 | 2016 | mutex_unlock(&tty_mutex); |
98a27ba4 EB |
2017 | /* Reset controlling tty. */ |
2018 | if (drop_tty) | |
2019 | no_tty(); | |
1da177e4 LT |
2020 | |
2021 | /* Revalidate access to inherited open files. */ | |
2022 | ||
2023 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
2024 | ||
2025 | spin_lock(&files->file_lock); | |
2026 | for (;;) { | |
2027 | unsigned long set, i; | |
2028 | int fd; | |
2029 | ||
2030 | j++; | |
2031 | i = j * __NFDBITS; | |
badf1662 | 2032 | fdt = files_fdtable(files); |
bbea9f69 | 2033 | if (i >= fdt->max_fds) |
1da177e4 | 2034 | break; |
badf1662 | 2035 | set = fdt->open_fds->fds_bits[j]; |
1da177e4 LT |
2036 | if (!set) |
2037 | continue; | |
2038 | spin_unlock(&files->file_lock); | |
2039 | for ( ; set ; i++,set >>= 1) { | |
2040 | if (set & 1) { | |
2041 | file = fget(i); | |
2042 | if (!file) | |
2043 | continue; | |
2044 | if (file_has_perm(current, | |
2045 | file, | |
2046 | file_to_av(file))) { | |
2047 | sys_close(i); | |
2048 | fd = get_unused_fd(); | |
2049 | if (fd != i) { | |
2050 | if (fd >= 0) | |
2051 | put_unused_fd(fd); | |
2052 | fput(file); | |
2053 | continue; | |
2054 | } | |
2055 | if (devnull) { | |
095975da | 2056 | get_file(devnull); |
1da177e4 LT |
2057 | } else { |
2058 | devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); | |
fc5d81e6 AM |
2059 | if (IS_ERR(devnull)) { |
2060 | devnull = NULL; | |
1da177e4 LT |
2061 | put_unused_fd(fd); |
2062 | fput(file); | |
2063 | continue; | |
2064 | } | |
2065 | } | |
2066 | fd_install(fd, devnull); | |
2067 | } | |
2068 | fput(file); | |
2069 | } | |
2070 | } | |
2071 | spin_lock(&files->file_lock); | |
2072 | ||
2073 | } | |
2074 | spin_unlock(&files->file_lock); | |
2075 | } | |
2076 | ||
2077 | static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) | |
2078 | { | |
2079 | struct task_security_struct *tsec; | |
2080 | struct bprm_security_struct *bsec; | |
2081 | u32 sid; | |
2082 | int rc; | |
2083 | ||
2084 | secondary_ops->bprm_apply_creds(bprm, unsafe); | |
2085 | ||
2086 | tsec = current->security; | |
2087 | ||
2088 | bsec = bprm->security; | |
2089 | sid = bsec->sid; | |
2090 | ||
2091 | tsec->osid = tsec->sid; | |
2092 | bsec->unsafe = 0; | |
2093 | if (tsec->sid != sid) { | |
2094 | /* Check for shared state. If not ok, leave SID | |
2095 | unchanged and kill. */ | |
2096 | if (unsafe & LSM_UNSAFE_SHARE) { | |
2097 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, | |
2098 | PROCESS__SHARE, NULL); | |
2099 | if (rc) { | |
2100 | bsec->unsafe = 1; | |
2101 | return; | |
2102 | } | |
2103 | } | |
2104 | ||
2105 | /* Check for ptracing, and update the task SID if ok. | |
2106 | Otherwise, leave SID unchanged and kill. */ | |
2107 | if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
2108 | rc = avc_has_perm(tsec->ptrace_sid, sid, | |
2109 | SECCLASS_PROCESS, PROCESS__PTRACE, | |
2110 | NULL); | |
2111 | if (rc) { | |
2112 | bsec->unsafe = 1; | |
2113 | return; | |
2114 | } | |
2115 | } | |
2116 | tsec->sid = sid; | |
2117 | } | |
2118 | } | |
2119 | ||
2120 | /* | |
2121 | * called after apply_creds without the task lock held | |
2122 | */ | |
2123 | static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) | |
2124 | { | |
2125 | struct task_security_struct *tsec; | |
2126 | struct rlimit *rlim, *initrlim; | |
2127 | struct itimerval itimer; | |
2128 | struct bprm_security_struct *bsec; | |
2129 | int rc, i; | |
2130 | ||
2131 | tsec = current->security; | |
2132 | bsec = bprm->security; | |
2133 | ||
2134 | if (bsec->unsafe) { | |
2135 | force_sig_specific(SIGKILL, current); | |
2136 | return; | |
2137 | } | |
2138 | if (tsec->osid == tsec->sid) | |
2139 | return; | |
2140 | ||
2141 | /* Close files for which the new task SID is not authorized. */ | |
2142 | flush_unauthorized_files(current->files); | |
2143 | ||
2144 | /* Check whether the new SID can inherit signal state | |
2145 | from the old SID. If not, clear itimers to avoid | |
2146 | subsequent signal generation and flush and unblock | |
2147 | signals. This must occur _after_ the task SID has | |
2148 | been updated so that any kill done after the flush | |
2149 | will be checked against the new SID. */ | |
2150 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2151 | PROCESS__SIGINH, NULL); | |
2152 | if (rc) { | |
2153 | memset(&itimer, 0, sizeof itimer); | |
2154 | for (i = 0; i < 3; i++) | |
2155 | do_setitimer(i, &itimer, NULL); | |
2156 | flush_signals(current); | |
2157 | spin_lock_irq(¤t->sighand->siglock); | |
2158 | flush_signal_handlers(current, 1); | |
2159 | sigemptyset(¤t->blocked); | |
2160 | recalc_sigpending(); | |
2161 | spin_unlock_irq(¤t->sighand->siglock); | |
2162 | } | |
2163 | ||
4ac212ad SS |
2164 | /* Always clear parent death signal on SID transitions. */ |
2165 | current->pdeath_signal = 0; | |
2166 | ||
1da177e4 LT |
2167 | /* Check whether the new SID can inherit resource limits |
2168 | from the old SID. If not, reset all soft limits to | |
2169 | the lower of the current task's hard limit and the init | |
2170 | task's soft limit. Note that the setting of hard limits | |
2171 | (even to lower them) can be controlled by the setrlimit | |
2172 | check. The inclusion of the init task's soft limit into | |
2173 | the computation is to avoid resetting soft limits higher | |
2174 | than the default soft limit for cases where the default | |
2175 | is lower than the hard limit, e.g. RLIMIT_CORE or | |
2176 | RLIMIT_STACK.*/ | |
2177 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2178 | PROCESS__RLIMITINH, NULL); | |
2179 | if (rc) { | |
2180 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
2181 | rlim = current->signal->rlim + i; | |
2182 | initrlim = init_task.signal->rlim+i; | |
2183 | rlim->rlim_cur = min(rlim->rlim_max,initrlim->rlim_cur); | |
2184 | } | |
2185 | if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { | |
2186 | /* | |
2187 | * This will cause RLIMIT_CPU calculations | |
2188 | * to be refigured. | |
2189 | */ | |
2190 | current->it_prof_expires = jiffies_to_cputime(1); | |
2191 | } | |
2192 | } | |
2193 | ||
2194 | /* Wake up the parent if it is waiting so that it can | |
2195 | recheck wait permission to the new task SID. */ | |
2196 | wake_up_interruptible(¤t->parent->signal->wait_chldexit); | |
2197 | } | |
2198 | ||
2199 | /* superblock security operations */ | |
2200 | ||
2201 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2202 | { | |
2203 | return superblock_alloc_security(sb); | |
2204 | } | |
2205 | ||
2206 | static void selinux_sb_free_security(struct super_block *sb) | |
2207 | { | |
2208 | superblock_free_security(sb); | |
2209 | } | |
2210 | ||
2211 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2212 | { | |
2213 | if (plen > olen) | |
2214 | return 0; | |
2215 | ||
2216 | return !memcmp(prefix, option, plen); | |
2217 | } | |
2218 | ||
2219 | static inline int selinux_option(char *option, int len) | |
2220 | { | |
2221 | return (match_prefix("context=", sizeof("context=")-1, option, len) || | |
2222 | match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) || | |
0808925e EP |
2223 | match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) || |
2224 | match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len)); | |
1da177e4 LT |
2225 | } |
2226 | ||
2227 | static inline void take_option(char **to, char *from, int *first, int len) | |
2228 | { | |
2229 | if (!*first) { | |
2230 | **to = ','; | |
2231 | *to += 1; | |
3528a953 | 2232 | } else |
1da177e4 LT |
2233 | *first = 0; |
2234 | memcpy(*to, from, len); | |
2235 | *to += len; | |
2236 | } | |
2237 | ||
3528a953 CO |
2238 | static inline void take_selinux_option(char **to, char *from, int *first, |
2239 | int len) | |
2240 | { | |
2241 | int current_size = 0; | |
2242 | ||
2243 | if (!*first) { | |
2244 | **to = '|'; | |
2245 | *to += 1; | |
2246 | } | |
2247 | else | |
2248 | *first = 0; | |
2249 | ||
2250 | while (current_size < len) { | |
2251 | if (*from != '"') { | |
2252 | **to = *from; | |
2253 | *to += 1; | |
2254 | } | |
2255 | from += 1; | |
2256 | current_size += 1; | |
2257 | } | |
2258 | } | |
2259 | ||
1da177e4 LT |
2260 | static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy) |
2261 | { | |
2262 | int fnosec, fsec, rc = 0; | |
2263 | char *in_save, *in_curr, *in_end; | |
2264 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2265 | int open_quote = 0; |
1da177e4 LT |
2266 | |
2267 | in_curr = orig; | |
2268 | sec_curr = copy; | |
2269 | ||
2270 | /* Binary mount data: just copy */ | |
2271 | if (type->fs_flags & FS_BINARY_MOUNTDATA) { | |
2272 | copy_page(sec_curr, in_curr); | |
2273 | goto out; | |
2274 | } | |
2275 | ||
2276 | nosec = (char *)get_zeroed_page(GFP_KERNEL); | |
2277 | if (!nosec) { | |
2278 | rc = -ENOMEM; | |
2279 | goto out; | |
2280 | } | |
2281 | ||
2282 | nosec_save = nosec; | |
2283 | fnosec = fsec = 1; | |
2284 | in_save = in_end = orig; | |
2285 | ||
2286 | do { | |
3528a953 CO |
2287 | if (*in_end == '"') |
2288 | open_quote = !open_quote; | |
2289 | if ((*in_end == ',' && open_quote == 0) || | |
2290 | *in_end == '\0') { | |
1da177e4 LT |
2291 | int len = in_end - in_curr; |
2292 | ||
2293 | if (selinux_option(in_curr, len)) | |
3528a953 | 2294 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2295 | else |
2296 | take_option(&nosec, in_curr, &fnosec, len); | |
2297 | ||
2298 | in_curr = in_end + 1; | |
2299 | } | |
2300 | } while (*in_end++); | |
2301 | ||
6931dfc9 | 2302 | strcpy(in_save, nosec_save); |
da3caa20 | 2303 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2304 | out: |
2305 | return rc; | |
2306 | } | |
2307 | ||
2308 | static int selinux_sb_kern_mount(struct super_block *sb, void *data) | |
2309 | { | |
2310 | struct avc_audit_data ad; | |
2311 | int rc; | |
2312 | ||
2313 | rc = superblock_doinit(sb, data); | |
2314 | if (rc) | |
2315 | return rc; | |
2316 | ||
2317 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
2318 | ad.u.fs.dentry = sb->s_root; | |
2319 | return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); | |
2320 | } | |
2321 | ||
726c3342 | 2322 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 LT |
2323 | { |
2324 | struct avc_audit_data ad; | |
2325 | ||
2326 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
726c3342 DH |
2327 | ad.u.fs.dentry = dentry->d_sb->s_root; |
2328 | return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); | |
1da177e4 LT |
2329 | } |
2330 | ||
2331 | static int selinux_mount(char * dev_name, | |
2332 | struct nameidata *nd, | |
2333 | char * type, | |
2334 | unsigned long flags, | |
2335 | void * data) | |
2336 | { | |
2337 | int rc; | |
2338 | ||
2339 | rc = secondary_ops->sb_mount(dev_name, nd, type, flags, data); | |
2340 | if (rc) | |
2341 | return rc; | |
2342 | ||
2343 | if (flags & MS_REMOUNT) | |
2344 | return superblock_has_perm(current, nd->mnt->mnt_sb, | |
2345 | FILESYSTEM__REMOUNT, NULL); | |
2346 | else | |
2347 | return dentry_has_perm(current, nd->mnt, nd->dentry, | |
2348 | FILE__MOUNTON); | |
2349 | } | |
2350 | ||
2351 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2352 | { | |
2353 | int rc; | |
2354 | ||
2355 | rc = secondary_ops->sb_umount(mnt, flags); | |
2356 | if (rc) | |
2357 | return rc; | |
2358 | ||
2359 | return superblock_has_perm(current,mnt->mnt_sb, | |
2360 | FILESYSTEM__UNMOUNT,NULL); | |
2361 | } | |
2362 | ||
2363 | /* inode security operations */ | |
2364 | ||
2365 | static int selinux_inode_alloc_security(struct inode *inode) | |
2366 | { | |
2367 | return inode_alloc_security(inode); | |
2368 | } | |
2369 | ||
2370 | static void selinux_inode_free_security(struct inode *inode) | |
2371 | { | |
2372 | inode_free_security(inode); | |
2373 | } | |
2374 | ||
5e41ff9e SS |
2375 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
2376 | char **name, void **value, | |
2377 | size_t *len) | |
2378 | { | |
2379 | struct task_security_struct *tsec; | |
2380 | struct inode_security_struct *dsec; | |
2381 | struct superblock_security_struct *sbsec; | |
570bc1c2 | 2382 | u32 newsid, clen; |
5e41ff9e | 2383 | int rc; |
570bc1c2 | 2384 | char *namep = NULL, *context; |
5e41ff9e SS |
2385 | |
2386 | tsec = current->security; | |
2387 | dsec = dir->i_security; | |
2388 | sbsec = dir->i_sb->s_security; | |
5e41ff9e SS |
2389 | |
2390 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2391 | newsid = tsec->create_sid; | |
2392 | } else { | |
2393 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2394 | inode_mode_to_security_class(inode->i_mode), | |
2395 | &newsid); | |
2396 | if (rc) { | |
2397 | printk(KERN_WARNING "%s: " | |
2398 | "security_transition_sid failed, rc=%d (dev=%s " | |
2399 | "ino=%ld)\n", | |
2400 | __FUNCTION__, | |
2401 | -rc, inode->i_sb->s_id, inode->i_ino); | |
2402 | return rc; | |
2403 | } | |
2404 | } | |
2405 | ||
296fddf7 EP |
2406 | /* Possibly defer initialization to selinux_complete_init. */ |
2407 | if (sbsec->initialized) { | |
2408 | struct inode_security_struct *isec = inode->i_security; | |
2409 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2410 | isec->sid = newsid; | |
2411 | isec->initialized = 1; | |
2412 | } | |
5e41ff9e | 2413 | |
8aad3875 | 2414 | if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) |
25a74f3b SS |
2415 | return -EOPNOTSUPP; |
2416 | ||
570bc1c2 SS |
2417 | if (name) { |
2418 | namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_KERNEL); | |
2419 | if (!namep) | |
2420 | return -ENOMEM; | |
2421 | *name = namep; | |
2422 | } | |
5e41ff9e | 2423 | |
570bc1c2 SS |
2424 | if (value && len) { |
2425 | rc = security_sid_to_context(newsid, &context, &clen); | |
2426 | if (rc) { | |
2427 | kfree(namep); | |
2428 | return rc; | |
2429 | } | |
2430 | *value = context; | |
2431 | *len = clen; | |
5e41ff9e | 2432 | } |
5e41ff9e | 2433 | |
5e41ff9e SS |
2434 | return 0; |
2435 | } | |
2436 | ||
1da177e4 LT |
2437 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
2438 | { | |
2439 | return may_create(dir, dentry, SECCLASS_FILE); | |
2440 | } | |
2441 | ||
1da177e4 LT |
2442 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2443 | { | |
2444 | int rc; | |
2445 | ||
2446 | rc = secondary_ops->inode_link(old_dentry,dir,new_dentry); | |
2447 | if (rc) | |
2448 | return rc; | |
2449 | return may_link(dir, old_dentry, MAY_LINK); | |
2450 | } | |
2451 | ||
1da177e4 LT |
2452 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2453 | { | |
2454 | int rc; | |
2455 | ||
2456 | rc = secondary_ops->inode_unlink(dir, dentry); | |
2457 | if (rc) | |
2458 | return rc; | |
2459 | return may_link(dir, dentry, MAY_UNLINK); | |
2460 | } | |
2461 | ||
2462 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2463 | { | |
2464 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2465 | } | |
2466 | ||
1da177e4 LT |
2467 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
2468 | { | |
2469 | return may_create(dir, dentry, SECCLASS_DIR); | |
2470 | } | |
2471 | ||
1da177e4 LT |
2472 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2473 | { | |
2474 | return may_link(dir, dentry, MAY_RMDIR); | |
2475 | } | |
2476 | ||
2477 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
2478 | { | |
2479 | int rc; | |
2480 | ||
2481 | rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); | |
2482 | if (rc) | |
2483 | return rc; | |
2484 | ||
2485 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); | |
2486 | } | |
2487 | ||
1da177e4 LT |
2488 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
2489 | struct inode *new_inode, struct dentry *new_dentry) | |
2490 | { | |
2491 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2492 | } | |
2493 | ||
1da177e4 LT |
2494 | static int selinux_inode_readlink(struct dentry *dentry) |
2495 | { | |
2496 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2497 | } | |
2498 | ||
2499 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2500 | { | |
2501 | int rc; | |
2502 | ||
2503 | rc = secondary_ops->inode_follow_link(dentry,nameidata); | |
2504 | if (rc) | |
2505 | return rc; | |
2506 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2507 | } | |
2508 | ||
2509 | static int selinux_inode_permission(struct inode *inode, int mask, | |
2510 | struct nameidata *nd) | |
2511 | { | |
2512 | int rc; | |
2513 | ||
2514 | rc = secondary_ops->inode_permission(inode, mask, nd); | |
2515 | if (rc) | |
2516 | return rc; | |
2517 | ||
2518 | if (!mask) { | |
2519 | /* No permission to check. Existence test. */ | |
2520 | return 0; | |
2521 | } | |
2522 | ||
2523 | return inode_has_perm(current, inode, | |
2524 | file_mask_to_av(inode->i_mode, mask), NULL); | |
2525 | } | |
2526 | ||
2527 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2528 | { | |
2529 | int rc; | |
2530 | ||
2531 | rc = secondary_ops->inode_setattr(dentry, iattr); | |
2532 | if (rc) | |
2533 | return rc; | |
2534 | ||
2535 | if (iattr->ia_valid & ATTR_FORCE) | |
2536 | return 0; | |
2537 | ||
2538 | if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
2539 | ATTR_ATIME_SET | ATTR_MTIME_SET)) | |
2540 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2541 | ||
2542 | return dentry_has_perm(current, NULL, dentry, FILE__WRITE); | |
2543 | } | |
2544 | ||
2545 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2546 | { | |
2547 | return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); | |
2548 | } | |
2549 | ||
b5376771 SH |
2550 | static int selinux_inode_setotherxattr(struct dentry *dentry, char *name) |
2551 | { | |
2552 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
2553 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2554 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2555 | if (!capable(CAP_SETFCAP)) | |
2556 | return -EPERM; | |
2557 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2558 | /* A different attribute in the security namespace. | |
2559 | Restrict to administrator. */ | |
2560 | return -EPERM; | |
2561 | } | |
2562 | } | |
2563 | ||
2564 | /* Not an attribute we recognize, so just check the | |
2565 | ordinary setattr permission. */ | |
2566 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2567 | } | |
2568 | ||
1da177e4 LT |
2569 | static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value, size_t size, int flags) |
2570 | { | |
2571 | struct task_security_struct *tsec = current->security; | |
2572 | struct inode *inode = dentry->d_inode; | |
2573 | struct inode_security_struct *isec = inode->i_security; | |
2574 | struct superblock_security_struct *sbsec; | |
2575 | struct avc_audit_data ad; | |
2576 | u32 newsid; | |
2577 | int rc = 0; | |
2578 | ||
b5376771 SH |
2579 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2580 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2581 | |
2582 | sbsec = inode->i_sb->s_security; | |
2583 | if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) | |
2584 | return -EOPNOTSUPP; | |
2585 | ||
3bd858ab | 2586 | if (!is_owner_or_cap(inode)) |
1da177e4 LT |
2587 | return -EPERM; |
2588 | ||
2589 | AVC_AUDIT_DATA_INIT(&ad,FS); | |
2590 | ad.u.fs.dentry = dentry; | |
2591 | ||
2592 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, | |
2593 | FILE__RELABELFROM, &ad); | |
2594 | if (rc) | |
2595 | return rc; | |
2596 | ||
2597 | rc = security_context_to_sid(value, size, &newsid); | |
2598 | if (rc) | |
2599 | return rc; | |
2600 | ||
2601 | rc = avc_has_perm(tsec->sid, newsid, isec->sclass, | |
2602 | FILE__RELABELTO, &ad); | |
2603 | if (rc) | |
2604 | return rc; | |
2605 | ||
2606 | rc = security_validate_transition(isec->sid, newsid, tsec->sid, | |
2607 | isec->sclass); | |
2608 | if (rc) | |
2609 | return rc; | |
2610 | ||
2611 | return avc_has_perm(newsid, | |
2612 | sbsec->sid, | |
2613 | SECCLASS_FILESYSTEM, | |
2614 | FILESYSTEM__ASSOCIATE, | |
2615 | &ad); | |
2616 | } | |
2617 | ||
2618 | static void selinux_inode_post_setxattr(struct dentry *dentry, char *name, | |
2619 | void *value, size_t size, int flags) | |
2620 | { | |
2621 | struct inode *inode = dentry->d_inode; | |
2622 | struct inode_security_struct *isec = inode->i_security; | |
2623 | u32 newsid; | |
2624 | int rc; | |
2625 | ||
2626 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2627 | /* Not an attribute we recognize, so nothing to do. */ | |
2628 | return; | |
2629 | } | |
2630 | ||
2631 | rc = security_context_to_sid(value, size, &newsid); | |
2632 | if (rc) { | |
2633 | printk(KERN_WARNING "%s: unable to obtain SID for context " | |
2634 | "%s, rc=%d\n", __FUNCTION__, (char*)value, -rc); | |
2635 | return; | |
2636 | } | |
2637 | ||
2638 | isec->sid = newsid; | |
2639 | return; | |
2640 | } | |
2641 | ||
2642 | static int selinux_inode_getxattr (struct dentry *dentry, char *name) | |
2643 | { | |
1da177e4 LT |
2644 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); |
2645 | } | |
2646 | ||
2647 | static int selinux_inode_listxattr (struct dentry *dentry) | |
2648 | { | |
2649 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); | |
2650 | } | |
2651 | ||
2652 | static int selinux_inode_removexattr (struct dentry *dentry, char *name) | |
2653 | { | |
b5376771 SH |
2654 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2655 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2656 | |
2657 | /* No one is allowed to remove a SELinux security label. | |
2658 | You can change the label, but all data must be labeled. */ | |
2659 | return -EACCES; | |
2660 | } | |
2661 | ||
d381d8a9 JM |
2662 | /* |
2663 | * Copy the in-core inode security context value to the user. If the | |
2664 | * getxattr() prior to this succeeded, check to see if we need to | |
2665 | * canonicalize the value to be finally returned to the user. | |
2666 | * | |
2667 | * Permission check is handled by selinux_inode_getxattr hook. | |
2668 | */ | |
42492594 | 2669 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2670 | { |
42492594 DQ |
2671 | u32 size; |
2672 | int error; | |
2673 | char *context = NULL; | |
1da177e4 | 2674 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2675 | |
8c8570fb DK |
2676 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2677 | return -EOPNOTSUPP; | |
d381d8a9 | 2678 | |
42492594 DQ |
2679 | error = security_sid_to_context(isec->sid, &context, &size); |
2680 | if (error) | |
2681 | return error; | |
2682 | error = size; | |
2683 | if (alloc) { | |
2684 | *buffer = context; | |
2685 | goto out_nofree; | |
2686 | } | |
2687 | kfree(context); | |
2688 | out_nofree: | |
2689 | return error; | |
1da177e4 LT |
2690 | } |
2691 | ||
2692 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
2693 | const void *value, size_t size, int flags) | |
2694 | { | |
2695 | struct inode_security_struct *isec = inode->i_security; | |
2696 | u32 newsid; | |
2697 | int rc; | |
2698 | ||
2699 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2700 | return -EOPNOTSUPP; | |
2701 | ||
2702 | if (!value || !size) | |
2703 | return -EACCES; | |
2704 | ||
2705 | rc = security_context_to_sid((void*)value, size, &newsid); | |
2706 | if (rc) | |
2707 | return rc; | |
2708 | ||
2709 | isec->sid = newsid; | |
2710 | return 0; | |
2711 | } | |
2712 | ||
2713 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
2714 | { | |
2715 | const int len = sizeof(XATTR_NAME_SELINUX); | |
2716 | if (buffer && len <= buffer_size) | |
2717 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
2718 | return len; | |
2719 | } | |
2720 | ||
b5376771 SH |
2721 | static int selinux_inode_need_killpriv(struct dentry *dentry) |
2722 | { | |
2723 | return secondary_ops->inode_need_killpriv(dentry); | |
2724 | } | |
2725 | ||
2726 | static int selinux_inode_killpriv(struct dentry *dentry) | |
2727 | { | |
2728 | return secondary_ops->inode_killpriv(dentry); | |
2729 | } | |
2730 | ||
1da177e4 LT |
2731 | /* file security operations */ |
2732 | ||
788e7dd4 | 2733 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 2734 | { |
7420ed23 | 2735 | int rc; |
3d5ff529 | 2736 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2737 | |
2738 | if (!mask) { | |
2739 | /* No permission to check. Existence test. */ | |
2740 | return 0; | |
2741 | } | |
2742 | ||
2743 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
2744 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
2745 | mask |= MAY_APPEND; | |
2746 | ||
7420ed23 VY |
2747 | rc = file_has_perm(current, file, |
2748 | file_mask_to_av(inode->i_mode, mask)); | |
2749 | if (rc) | |
2750 | return rc; | |
2751 | ||
2752 | return selinux_netlbl_inode_permission(inode, mask); | |
1da177e4 LT |
2753 | } |
2754 | ||
788e7dd4 YN |
2755 | static int selinux_file_permission(struct file *file, int mask) |
2756 | { | |
2757 | struct inode *inode = file->f_path.dentry->d_inode; | |
2758 | struct task_security_struct *tsec = current->security; | |
2759 | struct file_security_struct *fsec = file->f_security; | |
2760 | struct inode_security_struct *isec = inode->i_security; | |
2761 | ||
2762 | if (!mask) { | |
2763 | /* No permission to check. Existence test. */ | |
2764 | return 0; | |
2765 | } | |
2766 | ||
2767 | if (tsec->sid == fsec->sid && fsec->isid == isec->sid | |
2768 | && fsec->pseqno == avc_policy_seqno()) | |
2769 | return selinux_netlbl_inode_permission(inode, mask); | |
2770 | ||
2771 | return selinux_revalidate_file_permission(file, mask); | |
2772 | } | |
2773 | ||
1da177e4 LT |
2774 | static int selinux_file_alloc_security(struct file *file) |
2775 | { | |
2776 | return file_alloc_security(file); | |
2777 | } | |
2778 | ||
2779 | static void selinux_file_free_security(struct file *file) | |
2780 | { | |
2781 | file_free_security(file); | |
2782 | } | |
2783 | ||
2784 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
2785 | unsigned long arg) | |
2786 | { | |
2787 | int error = 0; | |
2788 | ||
2789 | switch (cmd) { | |
2790 | case FIONREAD: | |
2791 | /* fall through */ | |
2792 | case FIBMAP: | |
2793 | /* fall through */ | |
2794 | case FIGETBSZ: | |
2795 | /* fall through */ | |
2796 | case EXT2_IOC_GETFLAGS: | |
2797 | /* fall through */ | |
2798 | case EXT2_IOC_GETVERSION: | |
2799 | error = file_has_perm(current, file, FILE__GETATTR); | |
2800 | break; | |
2801 | ||
2802 | case EXT2_IOC_SETFLAGS: | |
2803 | /* fall through */ | |
2804 | case EXT2_IOC_SETVERSION: | |
2805 | error = file_has_perm(current, file, FILE__SETATTR); | |
2806 | break; | |
2807 | ||
2808 | /* sys_ioctl() checks */ | |
2809 | case FIONBIO: | |
2810 | /* fall through */ | |
2811 | case FIOASYNC: | |
2812 | error = file_has_perm(current, file, 0); | |
2813 | break; | |
2814 | ||
2815 | case KDSKBENT: | |
2816 | case KDSKBSENT: | |
2817 | error = task_has_capability(current,CAP_SYS_TTY_CONFIG); | |
2818 | break; | |
2819 | ||
2820 | /* default case assumes that the command will go | |
2821 | * to the file's ioctl() function. | |
2822 | */ | |
2823 | default: | |
2824 | error = file_has_perm(current, file, FILE__IOCTL); | |
2825 | ||
2826 | } | |
2827 | return error; | |
2828 | } | |
2829 | ||
2830 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
2831 | { | |
2832 | #ifndef CONFIG_PPC32 | |
2833 | if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
2834 | /* | |
2835 | * We are making executable an anonymous mapping or a | |
2836 | * private file mapping that will also be writable. | |
2837 | * This has an additional check. | |
2838 | */ | |
2839 | int rc = task_has_perm(current, current, PROCESS__EXECMEM); | |
2840 | if (rc) | |
2841 | return rc; | |
2842 | } | |
2843 | #endif | |
2844 | ||
2845 | if (file) { | |
2846 | /* read access is always possible with a mapping */ | |
2847 | u32 av = FILE__READ; | |
2848 | ||
2849 | /* write access only matters if the mapping is shared */ | |
2850 | if (shared && (prot & PROT_WRITE)) | |
2851 | av |= FILE__WRITE; | |
2852 | ||
2853 | if (prot & PROT_EXEC) | |
2854 | av |= FILE__EXECUTE; | |
2855 | ||
2856 | return file_has_perm(current, file, av); | |
2857 | } | |
2858 | return 0; | |
2859 | } | |
2860 | ||
2861 | static int selinux_file_mmap(struct file *file, unsigned long reqprot, | |
ed032189 EP |
2862 | unsigned long prot, unsigned long flags, |
2863 | unsigned long addr, unsigned long addr_only) | |
1da177e4 | 2864 | { |
ed032189 EP |
2865 | int rc = 0; |
2866 | u32 sid = ((struct task_security_struct*)(current->security))->sid; | |
1da177e4 | 2867 | |
ed032189 EP |
2868 | if (addr < mmap_min_addr) |
2869 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, | |
2870 | MEMPROTECT__MMAP_ZERO, NULL); | |
2871 | if (rc || addr_only) | |
1da177e4 LT |
2872 | return rc; |
2873 | ||
2874 | if (selinux_checkreqprot) | |
2875 | prot = reqprot; | |
2876 | ||
2877 | return file_map_prot_check(file, prot, | |
2878 | (flags & MAP_TYPE) == MAP_SHARED); | |
2879 | } | |
2880 | ||
2881 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
2882 | unsigned long reqprot, | |
2883 | unsigned long prot) | |
2884 | { | |
2885 | int rc; | |
2886 | ||
2887 | rc = secondary_ops->file_mprotect(vma, reqprot, prot); | |
2888 | if (rc) | |
2889 | return rc; | |
2890 | ||
2891 | if (selinux_checkreqprot) | |
2892 | prot = reqprot; | |
2893 | ||
2894 | #ifndef CONFIG_PPC32 | |
db4c9641 SS |
2895 | if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
2896 | rc = 0; | |
2897 | if (vma->vm_start >= vma->vm_mm->start_brk && | |
2898 | vma->vm_end <= vma->vm_mm->brk) { | |
2899 | rc = task_has_perm(current, current, | |
2900 | PROCESS__EXECHEAP); | |
2901 | } else if (!vma->vm_file && | |
2902 | vma->vm_start <= vma->vm_mm->start_stack && | |
2903 | vma->vm_end >= vma->vm_mm->start_stack) { | |
2904 | rc = task_has_perm(current, current, PROCESS__EXECSTACK); | |
2905 | } else if (vma->vm_file && vma->anon_vma) { | |
2906 | /* | |
2907 | * We are making executable a file mapping that has | |
2908 | * had some COW done. Since pages might have been | |
2909 | * written, check ability to execute the possibly | |
2910 | * modified content. This typically should only | |
2911 | * occur for text relocations. | |
2912 | */ | |
2913 | rc = file_has_perm(current, vma->vm_file, | |
2914 | FILE__EXECMOD); | |
2915 | } | |