Commit | Line | Data |
---|---|---|
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> | |
828dfe1d EP |
7 | * Chris Vance, <cvance@nai.com> |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
1da177e4 LT |
10 | * |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
2069f457 EP |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> |
13 | * Eric Paris <eparis@redhat.com> | |
1da177e4 | 14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. |
828dfe1d | 15 | * <dgoeddel@trustedcs.com> |
effad8df | 16 | * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. |
828dfe1d | 17 | * Paul Moore <paul.moore@hp.com> |
788e7dd4 | 18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. |
828dfe1d | 19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> |
1da177e4 LT |
20 | * |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License version 2, | |
828dfe1d | 23 | * as published by the Free Software Foundation. |
1da177e4 LT |
24 | */ |
25 | ||
1da177e4 LT |
26 | #include <linux/init.h> |
27 | #include <linux/kernel.h> | |
28 | #include <linux/ptrace.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/sched.h> | |
31 | #include <linux/security.h> | |
32 | #include <linux/xattr.h> | |
33 | #include <linux/capability.h> | |
34 | #include <linux/unistd.h> | |
35 | #include <linux/mm.h> | |
36 | #include <linux/mman.h> | |
37 | #include <linux/slab.h> | |
38 | #include <linux/pagemap.h> | |
39 | #include <linux/swap.h> | |
1da177e4 LT |
40 | #include <linux/spinlock.h> |
41 | #include <linux/syscalls.h> | |
42 | #include <linux/file.h> | |
9f3acc31 | 43 | #include <linux/fdtable.h> |
1da177e4 LT |
44 | #include <linux/namei.h> |
45 | #include <linux/mount.h> | |
1da177e4 | 46 | #include <linux/proc_fs.h> |
1da177e4 LT |
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> |
f5269710 | 55 | #include <linux/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" |
3e112172 | 83 | #include "netport.h" |
d28d1e08 | 84 | #include "xfrm.h" |
c60475bf | 85 | #include "netlabel.h" |
9d57a7f9 | 86 | #include "audit.h" |
1da177e4 LT |
87 | |
88 | #define XATTR_SELINUX_SUFFIX "selinux" | |
89 | #define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX | |
90 | ||
c9180a57 EP |
91 | #define NUM_SEL_MNT_OPTS 4 |
92 | ||
1da177e4 LT |
93 | extern unsigned int policydb_loaded_version; |
94 | extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); | |
4e5ab4cb | 95 | extern int selinux_compat_net; |
20510f2f | 96 | extern struct security_operations *security_ops; |
1da177e4 | 97 | |
d621d35e PM |
98 | /* SECMARK reference count */ |
99 | atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); | |
100 | ||
1da177e4 | 101 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP |
828dfe1d | 102 | int selinux_enforcing; |
1da177e4 LT |
103 | |
104 | static int __init enforcing_setup(char *str) | |
105 | { | |
f5269710 EP |
106 | unsigned long enforcing; |
107 | if (!strict_strtoul(str, 0, &enforcing)) | |
108 | selinux_enforcing = enforcing ? 1 : 0; | |
1da177e4 LT |
109 | return 1; |
110 | } | |
111 | __setup("enforcing=", enforcing_setup); | |
112 | #endif | |
113 | ||
114 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
115 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
116 | ||
117 | static int __init selinux_enabled_setup(char *str) | |
118 | { | |
f5269710 EP |
119 | unsigned long enabled; |
120 | if (!strict_strtoul(str, 0, &enabled)) | |
121 | selinux_enabled = enabled ? 1 : 0; | |
1da177e4 LT |
122 | return 1; |
123 | } | |
124 | __setup("selinux=", selinux_enabled_setup); | |
30d55280 SS |
125 | #else |
126 | int selinux_enabled = 1; | |
1da177e4 LT |
127 | #endif |
128 | ||
1da177e4 | 129 | |
6f0f0fd4 JM |
130 | /* |
131 | * Minimal support for a secondary security module, | |
132 | * just to allow the use of the capability module. | |
133 | */ | |
828dfe1d | 134 | static struct security_operations *secondary_ops; |
1da177e4 LT |
135 | |
136 | /* Lists of inode and superblock security structures initialized | |
137 | before the policy was loaded. */ | |
138 | static LIST_HEAD(superblock_security_head); | |
139 | static DEFINE_SPINLOCK(sb_security_lock); | |
140 | ||
e18b890b | 141 | static struct kmem_cache *sel_inode_cache; |
7cae7e26 | 142 | |
d621d35e PM |
143 | /** |
144 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
145 | * | |
146 | * Description: | |
147 | * This function checks the SECMARK reference counter to see if any SECMARK | |
148 | * targets are currently configured, if the reference counter is greater than | |
149 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
150 | * enabled, false (0) if SECMARK is disabled. | |
151 | * | |
152 | */ | |
153 | static int selinux_secmark_enabled(void) | |
154 | { | |
155 | return (atomic_read(&selinux_secmark_refcount) > 0); | |
156 | } | |
157 | ||
1da177e4 LT |
158 | /* Allocate and free functions for each kind of security blob. */ |
159 | ||
160 | static int task_alloc_security(struct task_struct *task) | |
161 | { | |
162 | struct task_security_struct *tsec; | |
163 | ||
89d155ef | 164 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); |
1da177e4 LT |
165 | if (!tsec) |
166 | return -ENOMEM; | |
167 | ||
0356357c | 168 | tsec->osid = tsec->sid = SECINITSID_UNLABELED; |
1da177e4 LT |
169 | task->security = tsec; |
170 | ||
171 | return 0; | |
172 | } | |
173 | ||
174 | static void task_free_security(struct task_struct *task) | |
175 | { | |
176 | struct task_security_struct *tsec = task->security; | |
1da177e4 LT |
177 | task->security = NULL; |
178 | kfree(tsec); | |
179 | } | |
180 | ||
181 | static int inode_alloc_security(struct inode *inode) | |
182 | { | |
183 | struct task_security_struct *tsec = current->security; | |
184 | struct inode_security_struct *isec; | |
185 | ||
a02fe132 | 186 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); |
1da177e4 LT |
187 | if (!isec) |
188 | return -ENOMEM; | |
189 | ||
23970741 | 190 | mutex_init(&isec->lock); |
1da177e4 | 191 | INIT_LIST_HEAD(&isec->list); |
1da177e4 LT |
192 | isec->inode = inode; |
193 | isec->sid = SECINITSID_UNLABELED; | |
194 | isec->sclass = SECCLASS_FILE; | |
9ac49d22 | 195 | isec->task_sid = tsec->sid; |
1da177e4 LT |
196 | inode->i_security = isec; |
197 | ||
198 | return 0; | |
199 | } | |
200 | ||
201 | static void inode_free_security(struct inode *inode) | |
202 | { | |
203 | struct inode_security_struct *isec = inode->i_security; | |
204 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
205 | ||
1da177e4 LT |
206 | spin_lock(&sbsec->isec_lock); |
207 | if (!list_empty(&isec->list)) | |
208 | list_del_init(&isec->list); | |
209 | spin_unlock(&sbsec->isec_lock); | |
210 | ||
211 | inode->i_security = NULL; | |
7cae7e26 | 212 | kmem_cache_free(sel_inode_cache, isec); |
1da177e4 LT |
213 | } |
214 | ||
215 | static int file_alloc_security(struct file *file) | |
216 | { | |
217 | struct task_security_struct *tsec = current->security; | |
218 | struct file_security_struct *fsec; | |
219 | ||
26d2a4be | 220 | fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL); |
1da177e4 LT |
221 | if (!fsec) |
222 | return -ENOMEM; | |
223 | ||
9ac49d22 SS |
224 | fsec->sid = tsec->sid; |
225 | fsec->fown_sid = tsec->sid; | |
1da177e4 LT |
226 | file->f_security = fsec; |
227 | ||
228 | return 0; | |
229 | } | |
230 | ||
231 | static void file_free_security(struct file *file) | |
232 | { | |
233 | struct file_security_struct *fsec = file->f_security; | |
1da177e4 LT |
234 | file->f_security = NULL; |
235 | kfree(fsec); | |
236 | } | |
237 | ||
238 | static int superblock_alloc_security(struct super_block *sb) | |
239 | { | |
240 | struct superblock_security_struct *sbsec; | |
241 | ||
89d155ef | 242 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); |
1da177e4 LT |
243 | if (!sbsec) |
244 | return -ENOMEM; | |
245 | ||
bc7e982b | 246 | mutex_init(&sbsec->lock); |
1da177e4 LT |
247 | INIT_LIST_HEAD(&sbsec->list); |
248 | INIT_LIST_HEAD(&sbsec->isec_head); | |
249 | spin_lock_init(&sbsec->isec_lock); | |
1da177e4 LT |
250 | sbsec->sb = sb; |
251 | sbsec->sid = SECINITSID_UNLABELED; | |
252 | sbsec->def_sid = SECINITSID_FILE; | |
c312feb2 | 253 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; |
1da177e4 LT |
254 | sb->s_security = sbsec; |
255 | ||
256 | return 0; | |
257 | } | |
258 | ||
259 | static void superblock_free_security(struct super_block *sb) | |
260 | { | |
261 | struct superblock_security_struct *sbsec = sb->s_security; | |
262 | ||
1da177e4 LT |
263 | spin_lock(&sb_security_lock); |
264 | if (!list_empty(&sbsec->list)) | |
265 | list_del_init(&sbsec->list); | |
266 | spin_unlock(&sb_security_lock); | |
267 | ||
268 | sb->s_security = NULL; | |
269 | kfree(sbsec); | |
270 | } | |
271 | ||
7d877f3b | 272 | static int sk_alloc_security(struct sock *sk, int family, gfp_t priority) |
1da177e4 LT |
273 | { |
274 | struct sk_security_struct *ssec; | |
275 | ||
89d155ef | 276 | ssec = kzalloc(sizeof(*ssec), priority); |
1da177e4 LT |
277 | if (!ssec) |
278 | return -ENOMEM; | |
279 | ||
1da177e4 | 280 | ssec->peer_sid = SECINITSID_UNLABELED; |
892c141e | 281 | ssec->sid = SECINITSID_UNLABELED; |
1da177e4 LT |
282 | sk->sk_security = ssec; |
283 | ||
f74af6e8 | 284 | selinux_netlbl_sk_security_reset(ssec, family); |
99f59ed0 | 285 | |
1da177e4 LT |
286 | return 0; |
287 | } | |
288 | ||
289 | static void sk_free_security(struct sock *sk) | |
290 | { | |
291 | struct sk_security_struct *ssec = sk->sk_security; | |
292 | ||
1da177e4 LT |
293 | sk->sk_security = NULL; |
294 | kfree(ssec); | |
295 | } | |
1da177e4 LT |
296 | |
297 | /* The security server must be initialized before | |
298 | any labeling or access decisions can be provided. */ | |
299 | extern int ss_initialized; | |
300 | ||
301 | /* The file system's label must be initialized prior to use. */ | |
302 | ||
303 | static char *labeling_behaviors[6] = { | |
304 | "uses xattr", | |
305 | "uses transition SIDs", | |
306 | "uses task SIDs", | |
307 | "uses genfs_contexts", | |
308 | "not configured for labeling", | |
309 | "uses mountpoint labeling", | |
310 | }; | |
311 | ||
312 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
313 | ||
314 | static inline int inode_doinit(struct inode *inode) | |
315 | { | |
316 | return inode_doinit_with_dentry(inode, NULL); | |
317 | } | |
318 | ||
319 | enum { | |
31e87930 | 320 | Opt_error = -1, |
1da177e4 LT |
321 | Opt_context = 1, |
322 | Opt_fscontext = 2, | |
c9180a57 EP |
323 | Opt_defcontext = 3, |
324 | Opt_rootcontext = 4, | |
1da177e4 LT |
325 | }; |
326 | ||
327 | static match_table_t tokens = { | |
832cbd9a EP |
328 | {Opt_context, CONTEXT_STR "%s"}, |
329 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
330 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
331 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
31e87930 | 332 | {Opt_error, NULL}, |
1da177e4 LT |
333 | }; |
334 | ||
335 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
336 | ||
c312feb2 EP |
337 | static int may_context_mount_sb_relabel(u32 sid, |
338 | struct superblock_security_struct *sbsec, | |
339 | struct task_security_struct *tsec) | |
340 | { | |
341 | int rc; | |
342 | ||
343 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
344 | FILESYSTEM__RELABELFROM, NULL); | |
345 | if (rc) | |
346 | return rc; | |
347 | ||
348 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
349 | FILESYSTEM__RELABELTO, NULL); | |
350 | return rc; | |
351 | } | |
352 | ||
0808925e EP |
353 | static int may_context_mount_inode_relabel(u32 sid, |
354 | struct superblock_security_struct *sbsec, | |
355 | struct task_security_struct *tsec) | |
356 | { | |
357 | int rc; | |
358 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
359 | FILESYSTEM__RELABELFROM, NULL); | |
360 | if (rc) | |
361 | return rc; | |
362 | ||
363 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
364 | FILESYSTEM__ASSOCIATE, NULL); | |
365 | return rc; | |
366 | } | |
367 | ||
c9180a57 | 368 | static int sb_finish_set_opts(struct super_block *sb) |
1da177e4 | 369 | { |
1da177e4 | 370 | struct superblock_security_struct *sbsec = sb->s_security; |
c9180a57 EP |
371 | struct dentry *root = sb->s_root; |
372 | struct inode *root_inode = root->d_inode; | |
373 | int rc = 0; | |
1da177e4 | 374 | |
c9180a57 EP |
375 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { |
376 | /* Make sure that the xattr handler exists and that no | |
377 | error other than -ENODATA is returned by getxattr on | |
378 | the root directory. -ENODATA is ok, as this may be | |
379 | the first boot of the SELinux kernel before we have | |
380 | assigned xattr values to the filesystem. */ | |
381 | if (!root_inode->i_op->getxattr) { | |
382 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
383 | "xattr support\n", sb->s_id, sb->s_type->name); | |
384 | rc = -EOPNOTSUPP; | |
385 | goto out; | |
386 | } | |
387 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
388 | if (rc < 0 && rc != -ENODATA) { | |
389 | if (rc == -EOPNOTSUPP) | |
390 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
391 | "%s) has no security xattr handler\n", | |
392 | sb->s_id, sb->s_type->name); | |
393 | else | |
394 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
395 | "%s) getxattr errno %d\n", sb->s_id, | |
396 | sb->s_type->name, -rc); | |
397 | goto out; | |
398 | } | |
399 | } | |
1da177e4 | 400 | |
c9180a57 | 401 | sbsec->initialized = 1; |
1da177e4 | 402 | |
c9180a57 EP |
403 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) |
404 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
405 | sb->s_id, sb->s_type->name); | |
406 | else | |
407 | printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n", | |
408 | sb->s_id, sb->s_type->name, | |
409 | labeling_behaviors[sbsec->behavior-1]); | |
1da177e4 | 410 | |
c9180a57 EP |
411 | /* Initialize the root inode. */ |
412 | rc = inode_doinit_with_dentry(root_inode, root); | |
1da177e4 | 413 | |
c9180a57 EP |
414 | /* Initialize any other inodes associated with the superblock, e.g. |
415 | inodes created prior to initial policy load or inodes created | |
416 | during get_sb by a pseudo filesystem that directly | |
417 | populates itself. */ | |
418 | spin_lock(&sbsec->isec_lock); | |
419 | next_inode: | |
420 | if (!list_empty(&sbsec->isec_head)) { | |
421 | struct inode_security_struct *isec = | |
422 | list_entry(sbsec->isec_head.next, | |
423 | struct inode_security_struct, list); | |
424 | struct inode *inode = isec->inode; | |
425 | spin_unlock(&sbsec->isec_lock); | |
426 | inode = igrab(inode); | |
427 | if (inode) { | |
428 | if (!IS_PRIVATE(inode)) | |
429 | inode_doinit(inode); | |
430 | iput(inode); | |
431 | } | |
432 | spin_lock(&sbsec->isec_lock); | |
433 | list_del_init(&isec->list); | |
434 | goto next_inode; | |
435 | } | |
436 | spin_unlock(&sbsec->isec_lock); | |
437 | out: | |
438 | return rc; | |
439 | } | |
1da177e4 | 440 | |
c9180a57 EP |
441 | /* |
442 | * This function should allow an FS to ask what it's mount security | |
443 | * options were so it can use those later for submounts, displaying | |
444 | * mount options, or whatever. | |
445 | */ | |
446 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
e0007529 | 447 | struct security_mnt_opts *opts) |
c9180a57 EP |
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 | |
e0007529 | 455 | security_init_mnt_opts(opts); |
1da177e4 | 456 | |
c9180a57 EP |
457 | if (!sbsec->initialized) |
458 | return -EINVAL; | |
1da177e4 | 459 | |
c9180a57 EP |
460 | if (!ss_initialized) |
461 | return -EINVAL; | |
1da177e4 | 462 | |
c9180a57 EP |
463 | /* |
464 | * if we ever use sbsec flags for anything other than tracking mount | |
465 | * settings this is going to need a mask | |
466 | */ | |
467 | tmp = sbsec->flags; | |
468 | /* count the number of mount options for this sb */ | |
469 | for (i = 0; i < 8; i++) { | |
470 | if (tmp & 0x01) | |
e0007529 | 471 | opts->num_mnt_opts++; |
c9180a57 EP |
472 | tmp >>= 1; |
473 | } | |
1da177e4 | 474 | |
e0007529 EP |
475 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); |
476 | if (!opts->mnt_opts) { | |
c9180a57 EP |
477 | rc = -ENOMEM; |
478 | goto out_free; | |
479 | } | |
1da177e4 | 480 | |
e0007529 EP |
481 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); |
482 | if (!opts->mnt_opts_flags) { | |
c9180a57 EP |
483 | rc = -ENOMEM; |
484 | goto out_free; | |
485 | } | |
1da177e4 | 486 | |
c9180a57 EP |
487 | i = 0; |
488 | if (sbsec->flags & FSCONTEXT_MNT) { | |
489 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
490 | if (rc) | |
491 | goto out_free; | |
e0007529 EP |
492 | opts->mnt_opts[i] = context; |
493 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
c9180a57 EP |
494 | } |
495 | if (sbsec->flags & CONTEXT_MNT) { | |
496 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
497 | if (rc) | |
498 | goto out_free; | |
e0007529 EP |
499 | opts->mnt_opts[i] = context; |
500 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
c9180a57 EP |
501 | } |
502 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
503 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
504 | if (rc) | |
505 | goto out_free; | |
e0007529 EP |
506 | opts->mnt_opts[i] = context; |
507 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
508 | } |
509 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
510 | struct inode *root = sbsec->sb->s_root->d_inode; | |
511 | struct inode_security_struct *isec = root->i_security; | |
0808925e | 512 | |
c9180a57 EP |
513 | rc = security_sid_to_context(isec->sid, &context, &len); |
514 | if (rc) | |
515 | goto out_free; | |
e0007529 EP |
516 | opts->mnt_opts[i] = context; |
517 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
c9180a57 | 518 | } |
1da177e4 | 519 | |
e0007529 | 520 | BUG_ON(i != opts->num_mnt_opts); |
1da177e4 | 521 | |
c9180a57 EP |
522 | return 0; |
523 | ||
524 | out_free: | |
e0007529 | 525 | security_free_mnt_opts(opts); |
c9180a57 EP |
526 | return rc; |
527 | } | |
1da177e4 | 528 | |
c9180a57 EP |
529 | static int bad_option(struct superblock_security_struct *sbsec, char flag, |
530 | u32 old_sid, u32 new_sid) | |
531 | { | |
532 | /* check if the old mount command had the same options */ | |
533 | if (sbsec->initialized) | |
534 | if (!(sbsec->flags & flag) || | |
535 | (old_sid != new_sid)) | |
536 | return 1; | |
537 | ||
538 | /* check if we were passed the same options twice, | |
539 | * aka someone passed context=a,context=b | |
540 | */ | |
541 | if (!sbsec->initialized) | |
542 | if (sbsec->flags & flag) | |
543 | return 1; | |
544 | return 0; | |
545 | } | |
e0007529 | 546 | |
c9180a57 EP |
547 | /* |
548 | * Allow filesystems with binary mount data to explicitly set mount point | |
549 | * labeling information. | |
550 | */ | |
e0007529 EP |
551 | static int selinux_set_mnt_opts(struct super_block *sb, |
552 | struct security_mnt_opts *opts) | |
c9180a57 EP |
553 | { |
554 | int rc = 0, i; | |
555 | struct task_security_struct *tsec = current->security; | |
556 | struct superblock_security_struct *sbsec = sb->s_security; | |
557 | const char *name = sb->s_type->name; | |
811f3799 EP |
558 | struct dentry *root = sb->s_root; |
559 | struct inode *root_inode = root->d_inode; | |
560 | struct inode_security_struct *root_isec = root_inode->i_security; | |
c9180a57 EP |
561 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; |
562 | u32 defcontext_sid = 0; | |
e0007529 EP |
563 | char **mount_options = opts->mnt_opts; |
564 | int *flags = opts->mnt_opts_flags; | |
565 | int num_opts = opts->num_mnt_opts; | |
811f3799 | 566 | bool can_xattr = false; |
c9180a57 EP |
567 | |
568 | mutex_lock(&sbsec->lock); | |
569 | ||
570 | if (!ss_initialized) { | |
571 | if (!num_opts) { | |
572 | /* Defer initialization until selinux_complete_init, | |
573 | after the initial policy is loaded and the security | |
574 | server is ready to handle calls. */ | |
575 | spin_lock(&sb_security_lock); | |
576 | if (list_empty(&sbsec->list)) | |
577 | list_add(&sbsec->list, &superblock_security_head); | |
578 | spin_unlock(&sb_security_lock); | |
579 | goto out; | |
580 | } | |
581 | rc = -EINVAL; | |
744ba35e EP |
582 | printk(KERN_WARNING "SELinux: Unable to set superblock options " |
583 | "before the security server is initialized\n"); | |
1da177e4 | 584 | goto out; |
c9180a57 | 585 | } |
1da177e4 | 586 | |
e0007529 EP |
587 | /* |
588 | * Binary mount data FS will come through this function twice. Once | |
589 | * from an explicit call and once from the generic calls from the vfs. | |
590 | * Since the generic VFS calls will not contain any security mount data | |
591 | * we need to skip the double mount verification. | |
592 | * | |
593 | * This does open a hole in which we will not notice if the first | |
594 | * mount using this sb set explict options and a second mount using | |
595 | * this sb does not set any security options. (The first options | |
596 | * will be used for both mounts) | |
597 | */ | |
598 | if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
599 | && (num_opts == 0)) | |
f5269710 | 600 | goto out; |
e0007529 | 601 | |
c9180a57 EP |
602 | /* |
603 | * parse the mount options, check if they are valid sids. | |
604 | * also check if someone is trying to mount the same sb more | |
605 | * than once with different security options. | |
606 | */ | |
607 | for (i = 0; i < num_opts; i++) { | |
608 | u32 sid; | |
609 | rc = security_context_to_sid(mount_options[i], | |
610 | strlen(mount_options[i]), &sid); | |
1da177e4 LT |
611 | if (rc) { |
612 | printk(KERN_WARNING "SELinux: security_context_to_sid" | |
613 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
c9180a57 EP |
614 | mount_options[i], sb->s_id, name, rc); |
615 | goto out; | |
616 | } | |
617 | switch (flags[i]) { | |
618 | case FSCONTEXT_MNT: | |
619 | fscontext_sid = sid; | |
620 | ||
621 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
622 | fscontext_sid)) | |
623 | goto out_double_mount; | |
624 | ||
625 | sbsec->flags |= FSCONTEXT_MNT; | |
626 | break; | |
627 | case CONTEXT_MNT: | |
628 | context_sid = sid; | |
629 | ||
630 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
631 | context_sid)) | |
632 | goto out_double_mount; | |
633 | ||
634 | sbsec->flags |= CONTEXT_MNT; | |
635 | break; | |
636 | case ROOTCONTEXT_MNT: | |
637 | rootcontext_sid = sid; | |
638 | ||
639 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
640 | rootcontext_sid)) | |
641 | goto out_double_mount; | |
642 | ||
643 | sbsec->flags |= ROOTCONTEXT_MNT; | |
644 | ||
645 | break; | |
646 | case DEFCONTEXT_MNT: | |
647 | defcontext_sid = sid; | |
648 | ||
649 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
650 | defcontext_sid)) | |
651 | goto out_double_mount; | |
652 | ||
653 | sbsec->flags |= DEFCONTEXT_MNT; | |
654 | ||
655 | break; | |
656 | default: | |
657 | rc = -EINVAL; | |
658 | goto out; | |
1da177e4 | 659 | } |
c9180a57 EP |
660 | } |
661 | ||
662 | if (sbsec->initialized) { | |
663 | /* previously mounted with options, but not on this attempt? */ | |
664 | if (sbsec->flags && !num_opts) | |
665 | goto out_double_mount; | |
666 | rc = 0; | |
667 | goto out; | |
668 | } | |
669 | ||
811f3799 | 670 | if (strcmp(name, "proc") == 0) |
c9180a57 EP |
671 | sbsec->proc = 1; |
672 | ||
811f3799 EP |
673 | /* |
674 | * test if the fs supports xattrs, fs_use might make use of this if the | |
675 | * fs has no definition in policy. | |
676 | */ | |
677 | if (root_inode->i_op->getxattr) { | |
678 | rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0); | |
679 | if (rc >= 0 || rc == -ENODATA) | |
680 | can_xattr = true; | |
681 | } | |
682 | ||
c9180a57 | 683 | /* Determine the labeling behavior to use for this filesystem type. */ |
811f3799 | 684 | rc = security_fs_use(name, &sbsec->behavior, &sbsec->sid, can_xattr); |
c9180a57 EP |
685 | if (rc) { |
686 | printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n", | |
811f3799 | 687 | __func__, name, rc); |
c9180a57 EP |
688 | goto out; |
689 | } | |
1da177e4 | 690 | |
c9180a57 EP |
691 | /* sets the context of the superblock for the fs being mounted. */ |
692 | if (fscontext_sid) { | |
693 | ||
694 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec); | |
1da177e4 | 695 | if (rc) |
c9180a57 | 696 | goto out; |
1da177e4 | 697 | |
c9180a57 | 698 | sbsec->sid = fscontext_sid; |
c312feb2 EP |
699 | } |
700 | ||
701 | /* | |
702 | * Switch to using mount point labeling behavior. | |
703 | * sets the label used on all file below the mountpoint, and will set | |
704 | * the superblock context if not already set. | |
705 | */ | |
c9180a57 EP |
706 | if (context_sid) { |
707 | if (!fscontext_sid) { | |
708 | rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec); | |
b04ea3ce | 709 | if (rc) |
c9180a57 EP |
710 | goto out; |
711 | sbsec->sid = context_sid; | |
b04ea3ce | 712 | } else { |
c9180a57 | 713 | rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec); |
b04ea3ce | 714 | if (rc) |
c9180a57 | 715 | goto out; |
b04ea3ce | 716 | } |
c9180a57 EP |
717 | if (!rootcontext_sid) |
718 | rootcontext_sid = context_sid; | |
1da177e4 | 719 | |
c9180a57 | 720 | sbsec->mntpoint_sid = context_sid; |
c312feb2 | 721 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; |
1da177e4 LT |
722 | } |
723 | ||
c9180a57 EP |
724 | if (rootcontext_sid) { |
725 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec); | |
0808925e | 726 | if (rc) |
c9180a57 | 727 | goto out; |
0808925e | 728 | |
c9180a57 EP |
729 | root_isec->sid = rootcontext_sid; |
730 | root_isec->initialized = 1; | |
0808925e EP |
731 | } |
732 | ||
c9180a57 EP |
733 | if (defcontext_sid) { |
734 | if (sbsec->behavior != SECURITY_FS_USE_XATTR) { | |
735 | rc = -EINVAL; | |
736 | printk(KERN_WARNING "SELinux: defcontext option is " | |
737 | "invalid for this filesystem type\n"); | |
738 | goto out; | |
1da177e4 LT |
739 | } |
740 | ||
c9180a57 EP |
741 | if (defcontext_sid != sbsec->def_sid) { |
742 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
743 | sbsec, tsec); | |
744 | if (rc) | |
745 | goto out; | |
746 | } | |
1da177e4 | 747 | |
c9180a57 | 748 | sbsec->def_sid = defcontext_sid; |
1da177e4 LT |
749 | } |
750 | ||
c9180a57 | 751 | rc = sb_finish_set_opts(sb); |
1da177e4 | 752 | out: |
c9180a57 | 753 | mutex_unlock(&sbsec->lock); |
1da177e4 | 754 | return rc; |
c9180a57 EP |
755 | out_double_mount: |
756 | rc = -EINVAL; | |
757 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
758 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
759 | goto out; | |
1da177e4 LT |
760 | } |
761 | ||
c9180a57 EP |
762 | static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb, |
763 | struct super_block *newsb) | |
1da177e4 | 764 | { |
c9180a57 EP |
765 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; |
766 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
1da177e4 | 767 | |
c9180a57 EP |
768 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); |
769 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
770 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
1da177e4 | 771 | |
0f5e6420 EP |
772 | /* |
773 | * if the parent was able to be mounted it clearly had no special lsm | |
774 | * mount options. thus we can safely put this sb on the list and deal | |
775 | * with it later | |
776 | */ | |
777 | if (!ss_initialized) { | |
778 | spin_lock(&sb_security_lock); | |
779 | if (list_empty(&newsbsec->list)) | |
780 | list_add(&newsbsec->list, &superblock_security_head); | |
781 | spin_unlock(&sb_security_lock); | |
782 | return; | |
783 | } | |
c9180a57 | 784 | |
c9180a57 EP |
785 | /* how can we clone if the old one wasn't set up?? */ |
786 | BUG_ON(!oldsbsec->initialized); | |
787 | ||
5a552617 EP |
788 | /* if fs is reusing a sb, just let its options stand... */ |
789 | if (newsbsec->initialized) | |
790 | return; | |
791 | ||
c9180a57 EP |
792 | mutex_lock(&newsbsec->lock); |
793 | ||
794 | newsbsec->flags = oldsbsec->flags; | |
795 | ||
796 | newsbsec->sid = oldsbsec->sid; | |
797 | newsbsec->def_sid = oldsbsec->def_sid; | |
798 | newsbsec->behavior = oldsbsec->behavior; | |
799 | ||
800 | if (set_context) { | |
801 | u32 sid = oldsbsec->mntpoint_sid; | |
802 | ||
803 | if (!set_fscontext) | |
804 | newsbsec->sid = sid; | |
805 | if (!set_rootcontext) { | |
806 | struct inode *newinode = newsb->s_root->d_inode; | |
807 | struct inode_security_struct *newisec = newinode->i_security; | |
808 | newisec->sid = sid; | |
809 | } | |
810 | newsbsec->mntpoint_sid = sid; | |
1da177e4 | 811 | } |
c9180a57 EP |
812 | if (set_rootcontext) { |
813 | const struct inode *oldinode = oldsb->s_root->d_inode; | |
814 | const struct inode_security_struct *oldisec = oldinode->i_security; | |
815 | struct inode *newinode = newsb->s_root->d_inode; | |
816 | struct inode_security_struct *newisec = newinode->i_security; | |
1da177e4 | 817 | |
c9180a57 | 818 | newisec->sid = oldisec->sid; |
1da177e4 LT |
819 | } |
820 | ||
c9180a57 EP |
821 | sb_finish_set_opts(newsb); |
822 | mutex_unlock(&newsbsec->lock); | |
823 | } | |
824 | ||
2e1479d9 AB |
825 | static int selinux_parse_opts_str(char *options, |
826 | struct security_mnt_opts *opts) | |
c9180a57 | 827 | { |
e0007529 | 828 | char *p; |
c9180a57 EP |
829 | char *context = NULL, *defcontext = NULL; |
830 | char *fscontext = NULL, *rootcontext = NULL; | |
e0007529 | 831 | int rc, num_mnt_opts = 0; |
1da177e4 | 832 | |
e0007529 | 833 | opts->num_mnt_opts = 0; |
1da177e4 | 834 | |
c9180a57 EP |
835 | /* Standard string-based options. */ |
836 | while ((p = strsep(&options, "|")) != NULL) { | |
837 | int token; | |
838 | substring_t args[MAX_OPT_ARGS]; | |
1da177e4 | 839 | |
c9180a57 EP |
840 | if (!*p) |
841 | continue; | |
1da177e4 | 842 | |
c9180a57 | 843 | token = match_token(p, tokens, args); |
1da177e4 | 844 | |
c9180a57 EP |
845 | switch (token) { |
846 | case Opt_context: | |
847 | if (context || defcontext) { | |
848 | rc = -EINVAL; | |
849 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
850 | goto out_err; | |
851 | } | |
852 | context = match_strdup(&args[0]); | |
853 | if (!context) { | |
854 | rc = -ENOMEM; | |
855 | goto out_err; | |
856 | } | |
857 | break; | |
858 | ||
859 | case Opt_fscontext: | |
860 | if (fscontext) { | |
861 | rc = -EINVAL; | |
862 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
863 | goto out_err; | |
864 | } | |
865 | fscontext = match_strdup(&args[0]); | |
866 | if (!fscontext) { | |
867 | rc = -ENOMEM; | |
868 | goto out_err; | |
869 | } | |
870 | break; | |
871 | ||
872 | case Opt_rootcontext: | |
873 | if (rootcontext) { | |
874 | rc = -EINVAL; | |
875 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
876 | goto out_err; | |
877 | } | |
878 | rootcontext = match_strdup(&args[0]); | |
879 | if (!rootcontext) { | |
880 | rc = -ENOMEM; | |
881 | goto out_err; | |
882 | } | |
883 | break; | |
884 | ||
885 | case Opt_defcontext: | |
886 | if (context || defcontext) { | |
887 | rc = -EINVAL; | |
888 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
889 | goto out_err; | |
890 | } | |
891 | defcontext = match_strdup(&args[0]); | |
892 | if (!defcontext) { | |
893 | rc = -ENOMEM; | |
894 | goto out_err; | |
895 | } | |
896 | break; | |
897 | ||
898 | default: | |
899 | rc = -EINVAL; | |
900 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
901 | goto out_err; | |
1da177e4 | 902 | |
1da177e4 | 903 | } |
1da177e4 | 904 | } |
c9180a57 | 905 | |
e0007529 EP |
906 | rc = -ENOMEM; |
907 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC); | |
908 | if (!opts->mnt_opts) | |
909 | goto out_err; | |
910 | ||
911 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC); | |
912 | if (!opts->mnt_opts_flags) { | |
913 | kfree(opts->mnt_opts); | |
914 | goto out_err; | |
915 | } | |
916 | ||
c9180a57 | 917 | if (fscontext) { |
e0007529 EP |
918 | opts->mnt_opts[num_mnt_opts] = fscontext; |
919 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
c9180a57 EP |
920 | } |
921 | if (context) { | |
e0007529 EP |
922 | opts->mnt_opts[num_mnt_opts] = context; |
923 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
c9180a57 EP |
924 | } |
925 | if (rootcontext) { | |
e0007529 EP |
926 | opts->mnt_opts[num_mnt_opts] = rootcontext; |
927 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
c9180a57 EP |
928 | } |
929 | if (defcontext) { | |
e0007529 EP |
930 | opts->mnt_opts[num_mnt_opts] = defcontext; |
931 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
c9180a57 EP |
932 | } |
933 | ||
e0007529 EP |
934 | opts->num_mnt_opts = num_mnt_opts; |
935 | return 0; | |
936 | ||
c9180a57 EP |
937 | out_err: |
938 | kfree(context); | |
939 | kfree(defcontext); | |
940 | kfree(fscontext); | |
941 | kfree(rootcontext); | |
1da177e4 LT |
942 | return rc; |
943 | } | |
e0007529 EP |
944 | /* |
945 | * string mount options parsing and call set the sbsec | |
946 | */ | |
947 | static int superblock_doinit(struct super_block *sb, void *data) | |
948 | { | |
949 | int rc = 0; | |
950 | char *options = data; | |
951 | struct security_mnt_opts opts; | |
952 | ||
953 | security_init_mnt_opts(&opts); | |
954 | ||
955 | if (!data) | |
956 | goto out; | |
957 | ||
958 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
959 | ||
960 | rc = selinux_parse_opts_str(options, &opts); | |
961 | if (rc) | |
962 | goto out_err; | |
963 | ||
964 | out: | |
965 | rc = selinux_set_mnt_opts(sb, &opts); | |
966 | ||
967 | out_err: | |
968 | security_free_mnt_opts(&opts); | |
969 | return rc; | |
970 | } | |
1da177e4 | 971 | |
2069f457 EP |
972 | void selinux_write_opts(struct seq_file *m, struct security_mnt_opts *opts) |
973 | { | |
974 | int i; | |
975 | char *prefix; | |
976 | ||
977 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
978 | char *has_comma = strchr(opts->mnt_opts[i], ','); | |
979 | ||
980 | switch (opts->mnt_opts_flags[i]) { | |
981 | case CONTEXT_MNT: | |
982 | prefix = CONTEXT_STR; | |
983 | break; | |
984 | case FSCONTEXT_MNT: | |
985 | prefix = FSCONTEXT_STR; | |
986 | break; | |
987 | case ROOTCONTEXT_MNT: | |
988 | prefix = ROOTCONTEXT_STR; | |
989 | break; | |
990 | case DEFCONTEXT_MNT: | |
991 | prefix = DEFCONTEXT_STR; | |
992 | break; | |
993 | default: | |
994 | BUG(); | |
995 | }; | |
996 | /* we need a comma before each option */ | |
997 | seq_putc(m, ','); | |
998 | seq_puts(m, prefix); | |
999 | if (has_comma) | |
1000 | seq_putc(m, '\"'); | |
1001 | seq_puts(m, opts->mnt_opts[i]); | |
1002 | if (has_comma) | |
1003 | seq_putc(m, '\"'); | |
1004 | } | |
1005 | } | |
1006 | ||
1007 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1008 | { | |
1009 | struct security_mnt_opts opts; | |
1010 | int rc; | |
1011 | ||
1012 | rc = selinux_get_mnt_opts(sb, &opts); | |
1013 | if (rc) | |
1014 | return rc; | |
1015 | ||
1016 | selinux_write_opts(m, &opts); | |
1017 | ||
1018 | security_free_mnt_opts(&opts); | |
1019 | ||
1020 | return rc; | |
1021 | } | |
1022 | ||
1da177e4 LT |
1023 | static inline u16 inode_mode_to_security_class(umode_t mode) |
1024 | { | |
1025 | switch (mode & S_IFMT) { | |
1026 | case S_IFSOCK: | |
1027 | return SECCLASS_SOCK_FILE; | |
1028 | case S_IFLNK: | |
1029 | return SECCLASS_LNK_FILE; | |
1030 | case S_IFREG: | |
1031 | return SECCLASS_FILE; | |
1032 | case S_IFBLK: | |
1033 | return SECCLASS_BLK_FILE; | |
1034 | case S_IFDIR: | |
1035 | return SECCLASS_DIR; | |
1036 | case S_IFCHR: | |
1037 | return SECCLASS_CHR_FILE; | |
1038 | case S_IFIFO: | |
1039 | return SECCLASS_FIFO_FILE; | |
1040 | ||
1041 | } | |
1042 | ||
1043 | return SECCLASS_FILE; | |
1044 | } | |
1045 | ||
13402580 JM |
1046 | static inline int default_protocol_stream(int protocol) |
1047 | { | |
1048 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1049 | } | |
1050 | ||
1051 | static inline int default_protocol_dgram(int protocol) | |
1052 | { | |
1053 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1054 | } | |
1055 | ||
1da177e4 LT |
1056 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) |
1057 | { | |
1058 | switch (family) { | |
1059 | case PF_UNIX: | |
1060 | switch (type) { | |
1061 | case SOCK_STREAM: | |
1062 | case SOCK_SEQPACKET: | |
1063 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1064 | case SOCK_DGRAM: | |
1065 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1066 | } | |
1067 | break; | |
1068 | case PF_INET: | |
1069 | case PF_INET6: | |
1070 | switch (type) { | |
1071 | case SOCK_STREAM: | |
13402580 JM |
1072 | if (default_protocol_stream(protocol)) |
1073 | return SECCLASS_TCP_SOCKET; | |
1074 | else | |
1075 | return SECCLASS_RAWIP_SOCKET; | |
1da177e4 | 1076 | case SOCK_DGRAM: |
13402580 JM |
1077 | if (default_protocol_dgram(protocol)) |
1078 | return SECCLASS_UDP_SOCKET; | |
1079 | else | |
1080 | return SECCLASS_RAWIP_SOCKET; | |
2ee92d46 JM |
1081 | case SOCK_DCCP: |
1082 | return SECCLASS_DCCP_SOCKET; | |
13402580 | 1083 | default: |
1da177e4 LT |
1084 | return SECCLASS_RAWIP_SOCKET; |
1085 | } | |
1086 | break; | |
1087 | case PF_NETLINK: | |
1088 | switch (protocol) { | |
1089 | case NETLINK_ROUTE: | |
1090 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1091 | case NETLINK_FIREWALL: | |
1092 | return SECCLASS_NETLINK_FIREWALL_SOCKET; | |
216efaaa | 1093 | case NETLINK_INET_DIAG: |
1da177e4 LT |
1094 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; |
1095 | case NETLINK_NFLOG: | |
1096 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1097 | case NETLINK_XFRM: | |
1098 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1099 | case NETLINK_SELINUX: | |
1100 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1101 | case NETLINK_AUDIT: | |
1102 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1103 | case NETLINK_IP6_FW: | |
1104 | return SECCLASS_NETLINK_IP6FW_SOCKET; | |
1105 | case NETLINK_DNRTMSG: | |
1106 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
0c9b7942 JM |
1107 | case NETLINK_KOBJECT_UEVENT: |
1108 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1da177e4 LT |
1109 | default: |
1110 | return SECCLASS_NETLINK_SOCKET; | |
1111 | } | |
1112 | case PF_PACKET: | |
1113 | return SECCLASS_PACKET_SOCKET; | |
1114 | case PF_KEY: | |
1115 | return SECCLASS_KEY_SOCKET; | |
3e3ff15e CP |
1116 | case PF_APPLETALK: |
1117 | return SECCLASS_APPLETALK_SOCKET; | |
1da177e4 LT |
1118 | } |
1119 | ||
1120 | return SECCLASS_SOCKET; | |
1121 | } | |
1122 | ||
1123 | #ifdef CONFIG_PROC_FS | |
1124 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1125 | u16 tclass, | |
1126 | u32 *sid) | |
1127 | { | |
1128 | int buflen, rc; | |
1129 | char *buffer, *path, *end; | |
1130 | ||
828dfe1d | 1131 | buffer = (char *)__get_free_page(GFP_KERNEL); |
1da177e4 LT |
1132 | if (!buffer) |
1133 | return -ENOMEM; | |
1134 | ||
1135 | buflen = PAGE_SIZE; | |
1136 | end = buffer+buflen; | |
1137 | *--end = '\0'; | |
1138 | buflen--; | |
1139 | path = end-1; | |
1140 | *path = '/'; | |
1141 | while (de && de != de->parent) { | |
1142 | buflen -= de->namelen + 1; | |
1143 | if (buflen < 0) | |
1144 | break; | |
1145 | end -= de->namelen; | |
1146 | memcpy(end, de->name, de->namelen); | |
1147 | *--end = '/'; | |
1148 | path = end; | |
1149 | de = de->parent; | |
1150 | } | |
1151 | rc = security_genfs_sid("proc", path, tclass, sid); | |
1152 | free_page((unsigned long)buffer); | |
1153 | return rc; | |
1154 | } | |
1155 | #else | |
1156 | static int selinux_proc_get_sid(struct proc_dir_entry *de, | |
1157 | u16 tclass, | |
1158 | u32 *sid) | |
1159 | { | |
1160 | return -EINVAL; | |
1161 | } | |
1162 | #endif | |
1163 | ||
1164 | /* The inode's security attributes must be initialized before first use. */ | |
1165 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1166 | { | |
1167 | struct superblock_security_struct *sbsec = NULL; | |
1168 | struct inode_security_struct *isec = inode->i_security; | |
1169 | u32 sid; | |
1170 | struct dentry *dentry; | |
1171 | #define INITCONTEXTLEN 255 | |
1172 | char *context = NULL; | |
1173 | unsigned len = 0; | |
1174 | int rc = 0; | |
1da177e4 LT |
1175 | |
1176 | if (isec->initialized) | |
1177 | goto out; | |
1178 | ||
23970741 | 1179 | mutex_lock(&isec->lock); |
1da177e4 | 1180 | if (isec->initialized) |
23970741 | 1181 | goto out_unlock; |
1da177e4 LT |
1182 | |
1183 | sbsec = inode->i_sb->s_security; | |
1184 | if (!sbsec->initialized) { | |
1185 | /* Defer initialization until selinux_complete_init, | |
1186 | after the initial policy is loaded and the security | |
1187 | server is ready to handle calls. */ | |
1188 | spin_lock(&sbsec->isec_lock); | |
1189 | if (list_empty(&isec->list)) | |
1190 | list_add(&isec->list, &sbsec->isec_head); | |
1191 | spin_unlock(&sbsec->isec_lock); | |
23970741 | 1192 | goto out_unlock; |
1da177e4 LT |
1193 | } |
1194 | ||
1195 | switch (sbsec->behavior) { | |
1196 | case SECURITY_FS_USE_XATTR: | |
1197 | if (!inode->i_op->getxattr) { | |
1198 | isec->sid = sbsec->def_sid; | |
1199 | break; | |
1200 | } | |
1201 | ||
1202 | /* Need a dentry, since the xattr API requires one. | |
1203 | Life would be simpler if we could just pass the inode. */ | |
1204 | if (opt_dentry) { | |
1205 | /* Called from d_instantiate or d_splice_alias. */ | |
1206 | dentry = dget(opt_dentry); | |
1207 | } else { | |
1208 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1209 | dentry = d_find_alias(inode); | |
1210 | } | |
1211 | if (!dentry) { | |
744ba35e | 1212 | printk(KERN_WARNING "SELinux: %s: no dentry for dev=%s " |
dd6f953a | 1213 | "ino=%ld\n", __func__, inode->i_sb->s_id, |
1da177e4 | 1214 | inode->i_ino); |
23970741 | 1215 | goto out_unlock; |
1da177e4 LT |
1216 | } |
1217 | ||
1218 | len = INITCONTEXTLEN; | |
869ab514 | 1219 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1220 | if (!context) { |
1221 | rc = -ENOMEM; | |
1222 | dput(dentry); | |
23970741 | 1223 | goto out_unlock; |
1da177e4 LT |
1224 | } |
1225 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1226 | context, len); | |
1227 | if (rc == -ERANGE) { | |
1228 | /* Need a larger buffer. Query for the right size. */ | |
1229 | rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX, | |
1230 | NULL, 0); | |
1231 | if (rc < 0) { | |
1232 | dput(dentry); | |
23970741 | 1233 | goto out_unlock; |
1da177e4 LT |
1234 | } |
1235 | kfree(context); | |
1236 | len = rc; | |
869ab514 | 1237 | context = kmalloc(len, GFP_NOFS); |
1da177e4 LT |
1238 | if (!context) { |
1239 | rc = -ENOMEM; | |
1240 | dput(dentry); | |
23970741 | 1241 | goto out_unlock; |
1da177e4 LT |
1242 | } |
1243 | rc = inode->i_op->getxattr(dentry, | |
1244 | XATTR_NAME_SELINUX, | |
1245 | context, len); | |
1246 | } | |
1247 | dput(dentry); | |
1248 | if (rc < 0) { | |
1249 | if (rc != -ENODATA) { | |
744ba35e | 1250 | printk(KERN_WARNING "SELinux: %s: getxattr returned " |
dd6f953a | 1251 | "%d for dev=%s ino=%ld\n", __func__, |
1da177e4 LT |
1252 | -rc, inode->i_sb->s_id, inode->i_ino); |
1253 | kfree(context); | |
23970741 | 1254 | goto out_unlock; |
1da177e4 LT |
1255 | } |
1256 | /* Map ENODATA to the default file SID */ | |
1257 | sid = sbsec->def_sid; | |
1258 | rc = 0; | |
1259 | } else { | |
f5c1d5b2 | 1260 | rc = security_context_to_sid_default(context, rc, &sid, |
869ab514 SS |
1261 | sbsec->def_sid, |
1262 | GFP_NOFS); | |
1da177e4 | 1263 | if (rc) { |
744ba35e | 1264 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " |
1da177e4 | 1265 | "returned %d for dev=%s ino=%ld\n", |
dd6f953a | 1266 | __func__, context, -rc, |
1da177e4 LT |
1267 | inode->i_sb->s_id, inode->i_ino); |
1268 | kfree(context); | |
1269 | /* Leave with the unlabeled SID */ | |
1270 | rc = 0; | |
1271 | break; | |
1272 | } | |
1273 | } | |
1274 | kfree(context); | |
1275 | isec->sid = sid; | |
1276 | break; | |
1277 | case SECURITY_FS_USE_TASK: | |
1278 | isec->sid = isec->task_sid; | |
1279 | break; | |
1280 | case SECURITY_FS_USE_TRANS: | |
1281 | /* Default to the fs SID. */ | |
1282 | isec->sid = sbsec->sid; | |
1283 | ||
1284 | /* Try to obtain a transition SID. */ | |
1285 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1286 | rc = security_transition_sid(isec->task_sid, | |
1287 | sbsec->sid, | |
1288 | isec->sclass, | |
1289 | &sid); | |
1290 | if (rc) | |
23970741 | 1291 | goto out_unlock; |
1da177e4 LT |
1292 | isec->sid = sid; |
1293 | break; | |
c312feb2 EP |
1294 | case SECURITY_FS_USE_MNTPOINT: |
1295 | isec->sid = sbsec->mntpoint_sid; | |
1296 | break; | |
1da177e4 | 1297 | default: |
c312feb2 | 1298 | /* Default to the fs superblock SID. */ |
1da177e4 LT |
1299 | isec->sid = sbsec->sid; |
1300 | ||
1301 | if (sbsec->proc) { | |
1302 | struct proc_inode *proci = PROC_I(inode); | |
1303 | if (proci->pde) { | |
1304 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1305 | rc = selinux_proc_get_sid(proci->pde, | |
1306 | isec->sclass, | |
1307 | &sid); | |
1308 | if (rc) | |
23970741 | 1309 | goto out_unlock; |
1da177e4 LT |
1310 | isec->sid = sid; |
1311 | } | |
1312 | } | |
1313 | break; | |
1314 | } | |
1315 | ||
1316 | isec->initialized = 1; | |
1317 | ||
23970741 EP |
1318 | out_unlock: |
1319 | mutex_unlock(&isec->lock); | |
1da177e4 LT |
1320 | out: |
1321 | if (isec->sclass == SECCLASS_FILE) | |
1322 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1da177e4 LT |
1323 | return rc; |
1324 | } | |
1325 | ||
1326 | /* Convert a Linux signal to an access vector. */ | |
1327 | static inline u32 signal_to_av(int sig) | |
1328 | { | |
1329 | u32 perm = 0; | |
1330 | ||
1331 | switch (sig) { | |
1332 | case SIGCHLD: | |
1333 | /* Commonly granted from child to parent. */ | |
1334 | perm = PROCESS__SIGCHLD; | |
1335 | break; | |
1336 | case SIGKILL: | |
1337 | /* Cannot be caught or ignored */ | |
1338 | perm = PROCESS__SIGKILL; | |
1339 | break; | |
1340 | case SIGSTOP: | |
1341 | /* Cannot be caught or ignored */ | |
1342 | perm = PROCESS__SIGSTOP; | |
1343 | break; | |
1344 | default: | |
1345 | /* All other signals. */ | |
1346 | perm = PROCESS__SIGNAL; | |
1347 | break; | |
1348 | } | |
1349 | ||
1350 | return perm; | |
1351 | } | |
1352 | ||
1353 | /* Check permission betweeen a pair of tasks, e.g. signal checks, | |
1354 | fork check, ptrace check, etc. */ | |
1355 | static int task_has_perm(struct task_struct *tsk1, | |
1356 | struct task_struct *tsk2, | |
1357 | u32 perms) | |
1358 | { | |
1359 | struct task_security_struct *tsec1, *tsec2; | |
1360 | ||
1361 | tsec1 = tsk1->security; | |
1362 | tsec2 = tsk2->security; | |
1363 | return avc_has_perm(tsec1->sid, tsec2->sid, | |
1364 | SECCLASS_PROCESS, perms, NULL); | |
1365 | } | |
1366 | ||
b68e418c SS |
1367 | #if CAP_LAST_CAP > 63 |
1368 | #error Fix SELinux to handle capabilities > 63. | |
1369 | #endif | |
1370 | ||
1da177e4 LT |
1371 | /* Check whether a task is allowed to use a capability. */ |
1372 | static int task_has_capability(struct task_struct *tsk, | |
1373 | int cap) | |
1374 | { | |
1375 | struct task_security_struct *tsec; | |
1376 | struct avc_audit_data ad; | |
b68e418c SS |
1377 | u16 sclass; |
1378 | u32 av = CAP_TO_MASK(cap); | |
1da177e4 LT |
1379 | |
1380 | tsec = tsk->security; | |
1381 | ||
828dfe1d | 1382 | AVC_AUDIT_DATA_INIT(&ad, CAP); |
1da177e4 LT |
1383 | ad.tsk = tsk; |
1384 | ad.u.cap = cap; | |
1385 | ||
b68e418c SS |
1386 | switch (CAP_TO_INDEX(cap)) { |
1387 | case 0: | |
1388 | sclass = SECCLASS_CAPABILITY; | |
1389 | break; | |
1390 | case 1: | |
1391 | sclass = SECCLASS_CAPABILITY2; | |
1392 | break; | |
1393 | default: | |
1394 | printk(KERN_ERR | |
1395 | "SELinux: out of range capability %d\n", cap); | |
1396 | BUG(); | |
1397 | } | |
1398 | return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad); | |
1da177e4 LT |
1399 | } |
1400 | ||
1401 | /* Check whether a task is allowed to use a system operation. */ | |
1402 | static int task_has_system(struct task_struct *tsk, | |
1403 | u32 perms) | |
1404 | { | |
1405 | struct task_security_struct *tsec; | |
1406 | ||
1407 | tsec = tsk->security; | |
1408 | ||
1409 | return avc_has_perm(tsec->sid, SECINITSID_KERNEL, | |
1410 | SECCLASS_SYSTEM, perms, NULL); | |
1411 | } | |
1412 | ||
1413 | /* Check whether a task has a particular permission to an inode. | |
1414 | The 'adp' parameter is optional and allows other audit | |
1415 | data to be passed (e.g. the dentry). */ | |
1416 | static int inode_has_perm(struct task_struct *tsk, | |
1417 | struct inode *inode, | |
1418 | u32 perms, | |
1419 | struct avc_audit_data *adp) | |
1420 | { | |
1421 | struct task_security_struct *tsec; | |
1422 | struct inode_security_struct *isec; | |
1423 | struct avc_audit_data ad; | |
1424 | ||
828dfe1d | 1425 | if (unlikely(IS_PRIVATE(inode))) |
bbaca6c2 SS |
1426 | return 0; |
1427 | ||
1da177e4 LT |
1428 | tsec = tsk->security; |
1429 | isec = inode->i_security; | |
1430 | ||
1431 | if (!adp) { | |
1432 | adp = &ad; | |
1433 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1434 | ad.u.fs.inode = inode; | |
1435 | } | |
1436 | ||
1437 | return avc_has_perm(tsec->sid, isec->sid, isec->sclass, perms, adp); | |
1438 | } | |
1439 | ||
1440 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1441 | the dentry to help the auditing code to more easily generate the | |
1442 | pathname if needed. */ | |
1443 | static inline int dentry_has_perm(struct task_struct *tsk, | |
1444 | struct vfsmount *mnt, | |
1445 | struct dentry *dentry, | |
1446 | u32 av) | |
1447 | { | |
1448 | struct inode *inode = dentry->d_inode; | |
1449 | struct avc_audit_data ad; | |
828dfe1d | 1450 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf JB |
1451 | ad.u.fs.path.mnt = mnt; |
1452 | ad.u.fs.path.dentry = dentry; | |
1da177e4 LT |
1453 | return inode_has_perm(tsk, inode, av, &ad); |
1454 | } | |
1455 | ||
1456 | /* Check whether a task can use an open file descriptor to | |
1457 | access an inode in a given way. Check access to the | |
1458 | descriptor itself, and then use dentry_has_perm to | |
1459 | check a particular permission to the file. | |
1460 | Access to the descriptor is implicitly granted if it | |
1461 | has the same SID as the process. If av is zero, then | |
1462 | access to the file is not checked, e.g. for cases | |
1463 | where only the descriptor is affected like seek. */ | |
858119e1 | 1464 | static int file_has_perm(struct task_struct *tsk, |
1da177e4 LT |
1465 | struct file *file, |
1466 | u32 av) | |
1467 | { | |
1468 | struct task_security_struct *tsec = tsk->security; | |
1469 | struct file_security_struct *fsec = file->f_security; | |
44707fdf | 1470 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
1471 | struct avc_audit_data ad; |
1472 | int rc; | |
1473 | ||
1474 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1475 | ad.u.fs.path = file->f_path; |
1da177e4 LT |
1476 | |
1477 | if (tsec->sid != fsec->sid) { | |
1478 | rc = avc_has_perm(tsec->sid, fsec->sid, | |
1479 | SECCLASS_FD, | |
1480 | FD__USE, | |
1481 | &ad); | |
1482 | if (rc) | |
1483 | return rc; | |
1484 | } | |
1485 | ||
1486 | /* av is zero if only checking access to the descriptor. */ | |
1487 | if (av) | |
1488 | return inode_has_perm(tsk, inode, av, &ad); | |
1489 | ||
1490 | return 0; | |
1491 | } | |
1492 | ||
1493 | /* Check whether a task can create a file. */ | |
1494 | static int may_create(struct inode *dir, | |
1495 | struct dentry *dentry, | |
1496 | u16 tclass) | |
1497 | { | |
1498 | struct task_security_struct *tsec; | |
1499 | struct inode_security_struct *dsec; | |
1500 | struct superblock_security_struct *sbsec; | |
1501 | u32 newsid; | |
1502 | struct avc_audit_data ad; | |
1503 | int rc; | |
1504 | ||
1505 | tsec = current->security; | |
1506 | dsec = dir->i_security; | |
1507 | sbsec = dir->i_sb->s_security; | |
1508 | ||
1509 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1510 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
1511 | |
1512 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, | |
1513 | DIR__ADD_NAME | DIR__SEARCH, | |
1514 | &ad); | |
1515 | if (rc) | |
1516 | return rc; | |
1517 | ||
1518 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
1519 | newsid = tsec->create_sid; | |
1520 | } else { | |
1521 | rc = security_transition_sid(tsec->sid, dsec->sid, tclass, | |
1522 | &newsid); | |
1523 | if (rc) | |
1524 | return rc; | |
1525 | } | |
1526 | ||
1527 | rc = avc_has_perm(tsec->sid, newsid, tclass, FILE__CREATE, &ad); | |
1528 | if (rc) | |
1529 | return rc; | |
1530 | ||
1531 | return avc_has_perm(newsid, sbsec->sid, | |
1532 | SECCLASS_FILESYSTEM, | |
1533 | FILESYSTEM__ASSOCIATE, &ad); | |
1534 | } | |
1535 | ||
4eb582cf ML |
1536 | /* Check whether a task can create a key. */ |
1537 | static int may_create_key(u32 ksid, | |
1538 | struct task_struct *ctx) | |
1539 | { | |
1540 | struct task_security_struct *tsec; | |
1541 | ||
1542 | tsec = ctx->security; | |
1543 | ||
1544 | return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); | |
1545 | } | |
1546 | ||
828dfe1d EP |
1547 | #define MAY_LINK 0 |
1548 | #define MAY_UNLINK 1 | |
1549 | #define MAY_RMDIR 2 | |
1da177e4 LT |
1550 | |
1551 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1552 | static int may_link(struct inode *dir, | |
1553 | struct dentry *dentry, | |
1554 | int kind) | |
1555 | ||
1556 | { | |
1557 | struct task_security_struct *tsec; | |
1558 | struct inode_security_struct *dsec, *isec; | |
1559 | struct avc_audit_data ad; | |
1560 | u32 av; | |
1561 | int rc; | |
1562 | ||
1563 | tsec = current->security; | |
1564 | dsec = dir->i_security; | |
1565 | isec = dentry->d_inode->i_security; | |
1566 | ||
1567 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 1568 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
1569 | |
1570 | av = DIR__SEARCH; | |
1571 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
1572 | rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1573 | if (rc) | |
1574 | return rc; | |
1575 | ||
1576 | switch (kind) { | |
1577 | case MAY_LINK: | |
1578 | av = FILE__LINK; | |
1579 | break; | |
1580 | case MAY_UNLINK: | |
1581 | av = FILE__UNLINK; | |
1582 | break; | |
1583 | case MAY_RMDIR: | |
1584 | av = DIR__RMDIR; | |
1585 | break; | |
1586 | default: | |
744ba35e EP |
1587 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", |
1588 | __func__, kind); | |
1da177e4 LT |
1589 | return 0; |
1590 | } | |
1591 | ||
1592 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, av, &ad); | |
1593 | return rc; | |
1594 | } | |
1595 | ||
1596 | static inline int may_rename(struct inode *old_dir, | |
1597 | struct dentry *old_dentry, | |
1598 | struct inode *new_dir, | |
1599 | struct dentry *new_dentry) | |
1600 | { | |
1601 | struct task_security_struct *tsec; | |
1602 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; | |
1603 | struct avc_audit_data ad; | |
1604 | u32 av; | |
1605 | int old_is_dir, new_is_dir; | |
1606 | int rc; | |
1607 | ||
1608 | tsec = current->security; | |
1609 | old_dsec = old_dir->i_security; | |
1610 | old_isec = old_dentry->d_inode->i_security; | |
1611 | old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode); | |
1612 | new_dsec = new_dir->i_security; | |
1613 | ||
1614 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
1615 | ||
44707fdf | 1616 | ad.u.fs.path.dentry = old_dentry; |
1da177e4 LT |
1617 | rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR, |
1618 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); | |
1619 | if (rc) | |
1620 | return rc; | |
1621 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1622 | old_isec->sclass, FILE__RENAME, &ad); | |
1623 | if (rc) | |
1624 | return rc; | |
1625 | if (old_is_dir && new_dir != old_dir) { | |
1626 | rc = avc_has_perm(tsec->sid, old_isec->sid, | |
1627 | old_isec->sclass, DIR__REPARENT, &ad); | |
1628 | if (rc) | |
1629 | return rc; | |
1630 | } | |
1631 | ||
44707fdf | 1632 | ad.u.fs.path.dentry = new_dentry; |
1da177e4 LT |
1633 | av = DIR__ADD_NAME | DIR__SEARCH; |
1634 | if (new_dentry->d_inode) | |
1635 | av |= DIR__REMOVE_NAME; | |
1636 | rc = avc_has_perm(tsec->sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1637 | if (rc) | |
1638 | return rc; | |
1639 | if (new_dentry->d_inode) { | |
1640 | new_isec = new_dentry->d_inode->i_security; | |
1641 | new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode); | |
1642 | rc = avc_has_perm(tsec->sid, new_isec->sid, | |
1643 | new_isec->sclass, | |
1644 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1645 | if (rc) | |
1646 | return rc; | |
1647 | } | |
1648 | ||
1649 | return 0; | |
1650 | } | |
1651 | ||
1652 | /* Check whether a task can perform a filesystem operation. */ | |
1653 | static int superblock_has_perm(struct task_struct *tsk, | |
1654 | struct super_block *sb, | |
1655 | u32 perms, | |
1656 | struct avc_audit_data *ad) | |
1657 | { | |
1658 | struct task_security_struct *tsec; | |
1659 | struct superblock_security_struct *sbsec; | |
1660 | ||
1661 | tsec = tsk->security; | |
1662 | sbsec = sb->s_security; | |
1663 | return avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
1664 | perms, ad); | |
1665 | } | |
1666 | ||
1667 | /* Convert a Linux mode and permission mask to an access vector. */ | |
1668 | static inline u32 file_mask_to_av(int mode, int mask) | |
1669 | { | |
1670 | u32 av = 0; | |
1671 | ||
1672 | if ((mode & S_IFMT) != S_IFDIR) { | |
1673 | if (mask & MAY_EXEC) | |
1674 | av |= FILE__EXECUTE; | |
1675 | if (mask & MAY_READ) | |
1676 | av |= FILE__READ; | |
1677 | ||
1678 | if (mask & MAY_APPEND) | |
1679 | av |= FILE__APPEND; | |
1680 | else if (mask & MAY_WRITE) | |
1681 | av |= FILE__WRITE; | |
1682 | ||
1683 | } else { | |
1684 | if (mask & MAY_EXEC) | |
1685 | av |= DIR__SEARCH; | |
1686 | if (mask & MAY_WRITE) | |
1687 | av |= DIR__WRITE; | |
1688 | if (mask & MAY_READ) | |
1689 | av |= DIR__READ; | |
1690 | } | |
1691 | ||
1692 | return av; | |
1693 | } | |
1694 | ||
b0c636b9 EP |
1695 | /* |
1696 | * Convert a file mask to an access vector and include the correct open | |
1697 | * open permission. | |
1698 | */ | |
1699 | static inline u32 open_file_mask_to_av(int mode, int mask) | |
1700 | { | |
1701 | u32 av = file_mask_to_av(mode, mask); | |
1702 | ||
1703 | if (selinux_policycap_openperm) { | |
1704 | /* | |
1705 | * lnk files and socks do not really have an 'open' | |
1706 | */ | |
1707 | if (S_ISREG(mode)) | |
1708 | av |= FILE__OPEN; | |
1709 | else if (S_ISCHR(mode)) | |
1710 | av |= CHR_FILE__OPEN; | |
1711 | else if (S_ISBLK(mode)) | |
1712 | av |= BLK_FILE__OPEN; | |
1713 | else if (S_ISFIFO(mode)) | |
1714 | av |= FIFO_FILE__OPEN; | |
1715 | else if (S_ISDIR(mode)) | |
1716 | av |= DIR__OPEN; | |
1717 | else | |
744ba35e EP |
1718 | printk(KERN_ERR "SELinux: WARNING: inside %s with " |
1719 | "unknown mode:%x\n", __func__, mode); | |
b0c636b9 EP |
1720 | } |
1721 | return av; | |
1722 | } | |
1723 | ||
1da177e4 LT |
1724 | /* Convert a Linux file to an access vector. */ |
1725 | static inline u32 file_to_av(struct file *file) | |
1726 | { | |
1727 | u32 av = 0; | |
1728 | ||
1729 | if (file->f_mode & FMODE_READ) | |
1730 | av |= FILE__READ; | |
1731 | if (file->f_mode & FMODE_WRITE) { | |
1732 | if (file->f_flags & O_APPEND) | |
1733 | av |= FILE__APPEND; | |
1734 | else | |
1735 | av |= FILE__WRITE; | |
1736 | } | |
0794c66d SS |
1737 | if (!av) { |
1738 | /* | |
1739 | * Special file opened with flags 3 for ioctl-only use. | |
1740 | */ | |
1741 | av = FILE__IOCTL; | |
1742 | } | |
1da177e4 LT |
1743 | |
1744 | return av; | |
1745 | } | |
1746 | ||
1da177e4 LT |
1747 | /* Hook functions begin here. */ |
1748 | ||
006ebb40 SS |
1749 | static int selinux_ptrace(struct task_struct *parent, |
1750 | struct task_struct *child, | |
1751 | unsigned int mode) | |
1da177e4 | 1752 | { |
1da177e4 LT |
1753 | int rc; |
1754 | ||
006ebb40 | 1755 | rc = secondary_ops->ptrace(parent, child, mode); |
1da177e4 LT |
1756 | if (rc) |
1757 | return rc; | |
1758 | ||
006ebb40 SS |
1759 | if (mode == PTRACE_MODE_READ) { |
1760 | struct task_security_struct *tsec = parent->security; | |
1761 | struct task_security_struct *csec = child->security; | |
1762 | return avc_has_perm(tsec->sid, csec->sid, | |
1763 | SECCLASS_FILE, FILE__READ, NULL); | |
1764 | } | |
1765 | ||
0356357c | 1766 | return task_has_perm(parent, child, PROCESS__PTRACE); |
1da177e4 LT |
1767 | } |
1768 | ||
1769 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1770 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1771 | { |
1772 | int error; | |
1773 | ||
1774 | error = task_has_perm(current, target, PROCESS__GETCAP); | |
1775 | if (error) | |
1776 | return error; | |
1777 | ||
1778 | return secondary_ops->capget(target, effective, inheritable, permitted); | |
1779 | } | |
1780 | ||
1781 | static int selinux_capset_check(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1782 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1783 | { |
1784 | int error; | |
1785 | ||
1786 | error = secondary_ops->capset_check(target, effective, inheritable, permitted); | |
1787 | if (error) | |
1788 | return error; | |
1789 | ||
1790 | return task_has_perm(current, target, PROCESS__SETCAP); | |
1791 | } | |
1792 | ||
1793 | static void selinux_capset_set(struct task_struct *target, kernel_cap_t *effective, | |
828dfe1d | 1794 | kernel_cap_t *inheritable, kernel_cap_t *permitted) |
1da177e4 LT |
1795 | { |
1796 | secondary_ops->capset_set(target, effective, inheritable, permitted); | |
1797 | } | |
1798 | ||
1799 | static int selinux_capable(struct task_struct *tsk, int cap) | |
1800 | { | |
1801 | int rc; | |
1802 | ||
1803 | rc = secondary_ops->capable(tsk, cap); | |
1804 | if (rc) | |
1805 | return rc; | |
1806 | ||
828dfe1d | 1807 | return task_has_capability(tsk, cap); |
1da177e4 LT |
1808 | } |
1809 | ||
3fbfa981 EB |
1810 | static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) |
1811 | { | |
1812 | int buflen, rc; | |
1813 | char *buffer, *path, *end; | |
1814 | ||
1815 | rc = -ENOMEM; | |
828dfe1d | 1816 | buffer = (char *)__get_free_page(GFP_KERNEL); |
3fbfa981 EB |
1817 | if (!buffer) |
1818 | goto out; | |
1819 | ||
1820 | buflen = PAGE_SIZE; | |
1821 | end = buffer+buflen; | |
1822 | *--end = '\0'; | |
1823 | buflen--; | |
1824 | path = end-1; | |
1825 | *path = '/'; | |
1826 | while (table) { | |
1827 | const char *name = table->procname; | |
1828 | size_t namelen = strlen(name); | |
1829 | buflen -= namelen + 1; | |
1830 | if (buflen < 0) | |
1831 | goto out_free; | |
1832 | end -= namelen; | |
1833 | memcpy(end, name, namelen); | |
1834 | *--end = '/'; | |
1835 | path = end; | |
1836 | table = table->parent; | |
1837 | } | |
b599fdfd EB |
1838 | buflen -= 4; |
1839 | if (buflen < 0) | |
1840 | goto out_free; | |
1841 | end -= 4; | |
1842 | memcpy(end, "/sys", 4); | |
1843 | path = end; | |
3fbfa981 EB |
1844 | rc = security_genfs_sid("proc", path, tclass, sid); |
1845 | out_free: | |
1846 | free_page((unsigned long)buffer); | |
1847 | out: | |
1848 | return rc; | |
1849 | } | |
1850 | ||
1da177e4 LT |
1851 | static int selinux_sysctl(ctl_table *table, int op) |
1852 | { | |
1853 | int error = 0; | |
1854 | u32 av; | |
1855 | struct task_security_struct *tsec; | |
1856 | u32 tsid; | |
1857 | int rc; | |
1858 | ||
1859 | rc = secondary_ops->sysctl(table, op); | |
1860 | if (rc) | |
1861 | return rc; | |
1862 | ||
1863 | tsec = current->security; | |
1864 | ||
3fbfa981 EB |
1865 | rc = selinux_sysctl_get_sid(table, (op == 0001) ? |
1866 | SECCLASS_DIR : SECCLASS_FILE, &tsid); | |
1da177e4 LT |
1867 | if (rc) { |
1868 | /* Default to the well-defined sysctl SID. */ | |
1869 | tsid = SECINITSID_SYSCTL; | |
1870 | } | |
1871 | ||
1872 | /* The op values are "defined" in sysctl.c, thereby creating | |
1873 | * a bad coupling between this module and sysctl.c */ | |
828dfe1d | 1874 | if (op == 001) { |
1da177e4 LT |
1875 | error = avc_has_perm(tsec->sid, tsid, |
1876 | SECCLASS_DIR, DIR__SEARCH, NULL); | |
1877 | } else { | |
1878 | av = 0; | |
1879 | if (op & 004) | |
1880 | av |= FILE__READ; | |
1881 | if (op & 002) | |
1882 | av |= FILE__WRITE; | |
1883 | if (av) | |
1884 | error = avc_has_perm(tsec->sid, tsid, | |
1885 | SECCLASS_FILE, av, NULL); | |
828dfe1d | 1886 | } |
1da177e4 LT |
1887 | |
1888 | return error; | |
1889 | } | |
1890 | ||
1891 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
1892 | { | |
1893 | int rc = 0; | |
1894 | ||
1895 | if (!sb) | |
1896 | return 0; | |
1897 | ||
1898 | switch (cmds) { | |
828dfe1d EP |
1899 | case Q_SYNC: |
1900 | case Q_QUOTAON: | |
1901 | case Q_QUOTAOFF: | |
1902 | case Q_SETINFO: | |
1903 | case Q_SETQUOTA: | |
1904 | rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD, | |
1905 | NULL); | |
1906 | break; | |
1907 | case Q_GETFMT: | |
1908 | case Q_GETINFO: | |
1909 | case Q_GETQUOTA: | |
1910 | rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET, | |
1911 | NULL); | |
1912 | break; | |
1913 | default: | |
1914 | rc = 0; /* let the kernel handle invalid cmds */ | |
1915 | break; | |
1da177e4 LT |
1916 | } |
1917 | return rc; | |
1918 | } | |
1919 | ||
1920 | static int selinux_quota_on(struct dentry *dentry) | |
1921 | { | |
1922 | return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON); | |
1923 | } | |
1924 | ||
1925 | static int selinux_syslog(int type) | |
1926 | { | |
1927 | int rc; | |
1928 | ||
1929 | rc = secondary_ops->syslog(type); | |
1930 | if (rc) | |
1931 | return rc; | |
1932 | ||
1933 | switch (type) { | |
828dfe1d EP |
1934 | case 3: /* Read last kernel messages */ |
1935 | case 10: /* Return size of the log buffer */ | |
1936 | rc = task_has_system(current, SYSTEM__SYSLOG_READ); | |
1937 | break; | |
1938 | case 6: /* Disable logging to console */ | |
1939 | case 7: /* Enable logging to console */ | |
1940 | case 8: /* Set level of messages printed to console */ | |
1941 | rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE); | |
1942 | break; | |
1943 | case 0: /* Close log */ | |
1944 | case 1: /* Open log */ | |
1945 | case 2: /* Read from log */ | |
1946 | case 4: /* Read/clear last kernel messages */ | |
1947 | case 5: /* Clear ring buffer */ | |
1948 | default: | |
1949 | rc = task_has_system(current, SYSTEM__SYSLOG_MOD); | |
1950 | break; | |
1da177e4 LT |
1951 | } |
1952 | return rc; | |
1953 | } | |
1954 | ||
1955 | /* | |
1956 | * Check that a process has enough memory to allocate a new virtual | |
1957 | * mapping. 0 means there is enough memory for the allocation to | |
1958 | * succeed and -ENOMEM implies there is not. | |
1959 | * | |
1960 | * Note that secondary_ops->capable and task_has_perm_noaudit return 0 | |
1961 | * if the capability is granted, but __vm_enough_memory requires 1 if | |
1962 | * the capability is granted. | |
1963 | * | |
1964 | * Do not audit the selinux permission check, as this is applied to all | |
1965 | * processes that allocate mappings. | |
1966 | */ | |
34b4e4aa | 1967 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) |
1da177e4 LT |
1968 | { |
1969 | int rc, cap_sys_admin = 0; | |
1970 | struct task_security_struct *tsec = current->security; | |
1971 | ||
1972 | rc = secondary_ops->capable(current, CAP_SYS_ADMIN); | |
1973 | if (rc == 0) | |
1974 | rc = avc_has_perm_noaudit(tsec->sid, tsec->sid, | |
2c3c05db SS |
1975 | SECCLASS_CAPABILITY, |
1976 | CAP_TO_MASK(CAP_SYS_ADMIN), | |
1977 | 0, | |
1978 | NULL); | |
1da177e4 LT |
1979 | |
1980 | if (rc == 0) | |
1981 | cap_sys_admin = 1; | |
1982 | ||
34b4e4aa | 1983 | return __vm_enough_memory(mm, pages, cap_sys_admin); |
1da177e4 LT |
1984 | } |
1985 | ||
0356357c RM |
1986 | /** |
1987 | * task_tracer_task - return the task that is tracing the given task | |
1988 | * @task: task to consider | |
1989 | * | |
1990 | * Returns NULL if noone is tracing @task, or the &struct task_struct | |
1991 | * pointer to its tracer. | |
1992 | * | |
1993 | * Must be called under rcu_read_lock(). | |
1994 | */ | |
1995 | static struct task_struct *task_tracer_task(struct task_struct *task) | |
1996 | { | |
1997 | if (task->ptrace & PT_PTRACED) | |
1998 | return rcu_dereference(task->parent); | |
1999 | return NULL; | |
2000 | } | |
2001 | ||
1da177e4 LT |
2002 | /* binprm security operations */ |
2003 | ||
2004 | static int selinux_bprm_alloc_security(struct linux_binprm *bprm) | |
2005 | { | |
2006 | struct bprm_security_struct *bsec; | |
2007 | ||
89d155ef | 2008 | bsec = kzalloc(sizeof(struct bprm_security_struct), GFP_KERNEL); |
1da177e4 LT |
2009 | if (!bsec) |
2010 | return -ENOMEM; | |
2011 | ||
1da177e4 LT |
2012 | bsec->sid = SECINITSID_UNLABELED; |
2013 | bsec->set = 0; | |
2014 | ||
2015 | bprm->security = bsec; | |
2016 | return 0; | |
2017 | } | |
2018 | ||
2019 | static int selinux_bprm_set_security(struct linux_binprm *bprm) | |
2020 | { | |
2021 | struct task_security_struct *tsec; | |
3d5ff529 | 2022 | struct inode *inode = bprm->file->f_path.dentry->d_inode; |
1da177e4 LT |
2023 | struct inode_security_struct *isec; |
2024 | struct bprm_security_struct *bsec; | |
2025 | u32 newsid; | |
2026 | struct avc_audit_data ad; | |
2027 | int rc; | |
2028 | ||
2029 | rc = secondary_ops->bprm_set_security(bprm); | |
2030 | if (rc) | |
2031 | return rc; | |
2032 | ||
2033 | bsec = bprm->security; | |
2034 | ||
2035 | if (bsec->set) | |
2036 | return 0; | |
2037 | ||
2038 | tsec = current->security; | |
2039 | isec = inode->i_security; | |
2040 | ||
2041 | /* Default to the current task SID. */ | |
2042 | bsec->sid = tsec->sid; | |
2043 | ||
28eba5bf | 2044 | /* Reset fs, key, and sock SIDs on execve. */ |
1da177e4 | 2045 | tsec->create_sid = 0; |
28eba5bf | 2046 | tsec->keycreate_sid = 0; |
42c3e03e | 2047 | tsec->sockcreate_sid = 0; |
1da177e4 LT |
2048 | |
2049 | if (tsec->exec_sid) { | |
2050 | newsid = tsec->exec_sid; | |
2051 | /* Reset exec SID on execve. */ | |
2052 | tsec->exec_sid = 0; | |
2053 | } else { | |
2054 | /* Check for a default transition on this program. */ | |
2055 | rc = security_transition_sid(tsec->sid, isec->sid, | |
828dfe1d | 2056 | SECCLASS_PROCESS, &newsid); |
1da177e4 LT |
2057 | if (rc) |
2058 | return rc; | |
2059 | } | |
2060 | ||
2061 | AVC_AUDIT_DATA_INIT(&ad, FS); | |
44707fdf | 2062 | ad.u.fs.path = bprm->file->f_path; |
1da177e4 | 2063 | |
3d5ff529 | 2064 | if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) |
1da177e4 LT |
2065 | newsid = tsec->sid; |
2066 | ||
828dfe1d | 2067 | if (tsec->sid == newsid) { |
1da177e4 LT |
2068 | rc = avc_has_perm(tsec->sid, isec->sid, |
2069 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); | |
2070 | if (rc) | |
2071 | return rc; | |
2072 | } else { | |
2073 | /* Check permissions for the transition. */ | |
2074 | rc = avc_has_perm(tsec->sid, newsid, | |
2075 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); | |
2076 | if (rc) | |
2077 | return rc; | |
2078 | ||
2079 | rc = avc_has_perm(newsid, isec->sid, | |
2080 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); | |
2081 | if (rc) | |
2082 | return rc; | |
2083 | ||
2084 | /* Clear any possibly unsafe personality bits on exec: */ | |
2085 | current->personality &= ~PER_CLEAR_ON_SETID; | |
2086 | ||
2087 | /* Set the security field to the new SID. */ | |
2088 | bsec->sid = newsid; | |
2089 | } | |
2090 | ||
2091 | bsec->set = 1; | |
2092 | return 0; | |
2093 | } | |
2094 | ||
828dfe1d | 2095 | static int selinux_bprm_check_security(struct linux_binprm *bprm) |
1da177e4 LT |
2096 | { |
2097 | return secondary_ops->bprm_check_security(bprm); | |
2098 | } | |
2099 | ||
2100 | ||
828dfe1d | 2101 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) |
1da177e4 LT |
2102 | { |
2103 | struct task_security_struct *tsec = current->security; | |
2104 | int atsecure = 0; | |
2105 | ||
2106 | if (tsec->osid != tsec->sid) { | |
2107 | /* Enable secure mode for SIDs transitions unless | |
2108 | the noatsecure permission is granted between | |
2109 | the two SIDs, i.e. ahp returns 0. */ | |
2110 | atsecure = avc_has_perm(tsec->osid, tsec->sid, | |
2111 | SECCLASS_PROCESS, | |
2112 | PROCESS__NOATSECURE, NULL); | |
2113 | } | |
2114 | ||
2115 | return (atsecure || secondary_ops->bprm_secureexec(bprm)); | |
2116 | } | |
2117 | ||
2118 | static void selinux_bprm_free_security(struct linux_binprm *bprm) | |
2119 | { | |
9a5f04bf | 2120 | kfree(bprm->security); |
1da177e4 | 2121 | bprm->security = NULL; |
1da177e4 LT |
2122 | } |
2123 | ||
2124 | extern struct vfsmount *selinuxfs_mount; | |
2125 | extern struct dentry *selinux_null; | |
2126 | ||
2127 | /* Derived from fs/exec.c:flush_old_files. */ | |
828dfe1d | 2128 | static inline void flush_unauthorized_files(struct files_struct *files) |
1da177e4 LT |
2129 | { |
2130 | struct avc_audit_data ad; | |
2131 | struct file *file, *devnull = NULL; | |
b20c8122 | 2132 | struct tty_struct *tty; |
badf1662 | 2133 | struct fdtable *fdt; |
1da177e4 | 2134 | long j = -1; |
24ec839c | 2135 | int drop_tty = 0; |
1da177e4 | 2136 | |
b20c8122 | 2137 | mutex_lock(&tty_mutex); |
24ec839c | 2138 | tty = get_current_tty(); |
1da177e4 LT |
2139 | if (tty) { |
2140 | file_list_lock(); | |
2f512016 | 2141 | file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list); |
1da177e4 LT |
2142 | if (file) { |
2143 | /* Revalidate access to controlling tty. | |
2144 | Use inode_has_perm on the tty inode directly rather | |
2145 | than using file_has_perm, as this particular open | |
2146 | file may belong to another process and we are only | |
2147 | interested in the inode-based check here. */ | |
3d5ff529 | 2148 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2149 | if (inode_has_perm(current, inode, |
2150 | FILE__READ | FILE__WRITE, NULL)) { | |
24ec839c | 2151 | drop_tty = 1; |
1da177e4 LT |
2152 | } |
2153 | } | |
2154 | file_list_unlock(); | |
2155 | } | |
b20c8122 | 2156 | mutex_unlock(&tty_mutex); |
98a27ba4 EB |
2157 | /* Reset controlling tty. */ |
2158 | if (drop_tty) | |
2159 | no_tty(); | |
1da177e4 LT |
2160 | |
2161 | /* Revalidate access to inherited open files. */ | |
2162 | ||
828dfe1d | 2163 | AVC_AUDIT_DATA_INIT(&ad, FS); |
1da177e4 LT |
2164 | |
2165 | spin_lock(&files->file_lock); | |
2166 | for (;;) { | |
2167 | unsigned long set, i; | |
2168 | int fd; | |
2169 | ||
2170 | j++; | |
2171 | i = j * __NFDBITS; | |
badf1662 | 2172 | fdt = files_fdtable(files); |
bbea9f69 | 2173 | if (i >= fdt->max_fds) |
1da177e4 | 2174 | break; |
badf1662 | 2175 | set = fdt->open_fds->fds_bits[j]; |
1da177e4 LT |
2176 | if (!set) |
2177 | continue; | |
2178 | spin_unlock(&files->file_lock); | |
828dfe1d | 2179 | for ( ; set ; i++, set >>= 1) { |
1da177e4 LT |
2180 | if (set & 1) { |
2181 | file = fget(i); | |
2182 | if (!file) | |
2183 | continue; | |
2184 | if (file_has_perm(current, | |
2185 | file, | |
2186 | file_to_av(file))) { | |
2187 | sys_close(i); | |
2188 | fd = get_unused_fd(); | |
2189 | if (fd != i) { | |
2190 | if (fd >= 0) | |
2191 | put_unused_fd(fd); | |
2192 | fput(file); | |
2193 | continue; | |
2194 | } | |
2195 | if (devnull) { | |
095975da | 2196 | get_file(devnull); |
1da177e4 LT |
2197 | } else { |
2198 | devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR); | |
fc5d81e6 AM |
2199 | if (IS_ERR(devnull)) { |
2200 | devnull = NULL; | |
1da177e4 LT |
2201 | put_unused_fd(fd); |
2202 | fput(file); | |
2203 | continue; | |
2204 | } | |
2205 | } | |
2206 | fd_install(fd, devnull); | |
2207 | } | |
2208 | fput(file); | |
2209 | } | |
2210 | } | |
2211 | spin_lock(&files->file_lock); | |
2212 | ||
2213 | } | |
2214 | spin_unlock(&files->file_lock); | |
2215 | } | |
2216 | ||
2217 | static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe) | |
2218 | { | |
2219 | struct task_security_struct *tsec; | |
2220 | struct bprm_security_struct *bsec; | |
2221 | u32 sid; | |
2222 | int rc; | |
2223 | ||
2224 | secondary_ops->bprm_apply_creds(bprm, unsafe); | |
2225 | ||
2226 | tsec = current->security; | |
2227 | ||
2228 | bsec = bprm->security; | |
2229 | sid = bsec->sid; | |
2230 | ||
2231 | tsec->osid = tsec->sid; | |
2232 | bsec->unsafe = 0; | |
2233 | if (tsec->sid != sid) { | |
2234 | /* Check for shared state. If not ok, leave SID | |
2235 | unchanged and kill. */ | |
2236 | if (unsafe & LSM_UNSAFE_SHARE) { | |
2237 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, | |
2238 | PROCESS__SHARE, NULL); | |
2239 | if (rc) { | |
2240 | bsec->unsafe = 1; | |
2241 | return; | |
2242 | } | |
2243 | } | |
2244 | ||
2245 | /* Check for ptracing, and update the task SID if ok. | |
2246 | Otherwise, leave SID unchanged and kill. */ | |
2247 | if (unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { | |
0356357c RM |
2248 | struct task_struct *tracer; |
2249 | struct task_security_struct *sec; | |
2250 | u32 ptsid = 0; | |
2251 | ||
2252 | rcu_read_lock(); | |
2253 | tracer = task_tracer_task(current); | |
2254 | if (likely(tracer != NULL)) { | |
2255 | sec = tracer->security; | |
2256 | ptsid = sec->sid; | |
2257 | } | |
2258 | rcu_read_unlock(); | |
2259 | ||
2260 | if (ptsid != 0) { | |
2261 | rc = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, | |
2262 | PROCESS__PTRACE, NULL); | |
2263 | if (rc) { | |
2264 | bsec->unsafe = 1; | |
2265 | return; | |
2266 | } | |
1da177e4 LT |
2267 | } |
2268 | } | |
2269 | tsec->sid = sid; | |
2270 | } | |
2271 | } | |
2272 | ||
2273 | /* | |
2274 | * called after apply_creds without the task lock held | |
2275 | */ | |
2276 | static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) | |
2277 | { | |
2278 | struct task_security_struct *tsec; | |
2279 | struct rlimit *rlim, *initrlim; | |
2280 | struct itimerval itimer; | |
2281 | struct bprm_security_struct *bsec; | |
2282 | int rc, i; | |
2283 | ||
2284 | tsec = current->security; | |
2285 | bsec = bprm->security; | |
2286 | ||
2287 | if (bsec->unsafe) { | |
2288 | force_sig_specific(SIGKILL, current); | |
2289 | return; | |
2290 | } | |
2291 | if (tsec->osid == tsec->sid) | |
2292 | return; | |
2293 | ||
2294 | /* Close files for which the new task SID is not authorized. */ | |
2295 | flush_unauthorized_files(current->files); | |
2296 | ||
2297 | /* Check whether the new SID can inherit signal state | |
2298 | from the old SID. If not, clear itimers to avoid | |
2299 | subsequent signal generation and flush and unblock | |
2300 | signals. This must occur _after_ the task SID has | |
2301 | been updated so that any kill done after the flush | |
2302 | will be checked against the new SID. */ | |
2303 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2304 | PROCESS__SIGINH, NULL); | |
2305 | if (rc) { | |
2306 | memset(&itimer, 0, sizeof itimer); | |
2307 | for (i = 0; i < 3; i++) | |
2308 | do_setitimer(i, &itimer, NULL); | |
2309 | flush_signals(current); | |
2310 | spin_lock_irq(¤t->sighand->siglock); | |
2311 | flush_signal_handlers(current, 1); | |
2312 | sigemptyset(¤t->blocked); | |
2313 | recalc_sigpending(); | |
2314 | spin_unlock_irq(¤t->sighand->siglock); | |
2315 | } | |
2316 | ||
4ac212ad SS |
2317 | /* Always clear parent death signal on SID transitions. */ |
2318 | current->pdeath_signal = 0; | |
2319 | ||
1da177e4 LT |
2320 | /* Check whether the new SID can inherit resource limits |
2321 | from the old SID. If not, reset all soft limits to | |
2322 | the lower of the current task's hard limit and the init | |
2323 | task's soft limit. Note that the setting of hard limits | |
2324 | (even to lower them) can be controlled by the setrlimit | |
2325 | check. The inclusion of the init task's soft limit into | |
2326 | the computation is to avoid resetting soft limits higher | |
2327 | than the default soft limit for cases where the default | |
2328 | is lower than the hard limit, e.g. RLIMIT_CORE or | |
2329 | RLIMIT_STACK.*/ | |
2330 | rc = avc_has_perm(tsec->osid, tsec->sid, SECCLASS_PROCESS, | |
2331 | PROCESS__RLIMITINH, NULL); | |
2332 | if (rc) { | |
2333 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
2334 | rlim = current->signal->rlim + i; | |
2335 | initrlim = init_task.signal->rlim+i; | |
828dfe1d | 2336 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); |
1da177e4 LT |
2337 | } |
2338 | if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { | |
2339 | /* | |
2340 | * This will cause RLIMIT_CPU calculations | |
2341 | * to be refigured. | |
2342 | */ | |
2343 | current->it_prof_expires = jiffies_to_cputime(1); | |
2344 | } | |
2345 | } | |
2346 | ||
2347 | /* Wake up the parent if it is waiting so that it can | |
2348 | recheck wait permission to the new task SID. */ | |
2349 | wake_up_interruptible(¤t->parent->signal->wait_chldexit); | |
2350 | } | |
2351 | ||
2352 | /* superblock security operations */ | |
2353 | ||
2354 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2355 | { | |
2356 | return superblock_alloc_security(sb); | |
2357 | } | |
2358 | ||
2359 | static void selinux_sb_free_security(struct super_block *sb) | |
2360 | { | |
2361 | superblock_free_security(sb); | |
2362 | } | |
2363 | ||
2364 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2365 | { | |
2366 | if (plen > olen) | |
2367 | return 0; | |
2368 | ||
2369 | return !memcmp(prefix, option, plen); | |
2370 | } | |
2371 | ||
2372 | static inline int selinux_option(char *option, int len) | |
2373 | { | |
832cbd9a EP |
2374 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || |
2375 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2376 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
2377 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len)); | |
1da177e4 LT |
2378 | } |
2379 | ||
2380 | static inline void take_option(char **to, char *from, int *first, int len) | |
2381 | { | |
2382 | if (!*first) { | |
2383 | **to = ','; | |
2384 | *to += 1; | |
3528a953 | 2385 | } else |
1da177e4 LT |
2386 | *first = 0; |
2387 | memcpy(*to, from, len); | |
2388 | *to += len; | |
2389 | } | |
2390 | ||
828dfe1d EP |
2391 | static inline void take_selinux_option(char **to, char *from, int *first, |
2392 | int len) | |
3528a953 CO |
2393 | { |
2394 | int current_size = 0; | |
2395 | ||
2396 | if (!*first) { | |
2397 | **to = '|'; | |
2398 | *to += 1; | |
828dfe1d | 2399 | } else |
3528a953 CO |
2400 | *first = 0; |
2401 | ||
2402 | while (current_size < len) { | |
2403 | if (*from != '"') { | |
2404 | **to = *from; | |
2405 | *to += 1; | |
2406 | } | |
2407 | from += 1; | |
2408 | current_size += 1; | |
2409 | } | |
2410 | } | |
2411 | ||
e0007529 | 2412 | static int selinux_sb_copy_data(char *orig, char *copy) |
1da177e4 LT |
2413 | { |
2414 | int fnosec, fsec, rc = 0; | |
2415 | char *in_save, *in_curr, *in_end; | |
2416 | char *sec_curr, *nosec_save, *nosec; | |
3528a953 | 2417 | int open_quote = 0; |
1da177e4 LT |
2418 | |
2419 | in_curr = orig; | |
2420 | sec_curr = copy; | |
2421 | ||
1da177e4 LT |
2422 | nosec = (char *)get_zeroed_page(GFP_KERNEL); |
2423 | if (!nosec) { | |
2424 | rc = -ENOMEM; | |
2425 | goto out; | |
2426 | } | |
2427 | ||
2428 | nosec_save = nosec; | |
2429 | fnosec = fsec = 1; | |
2430 | in_save = in_end = orig; | |
2431 | ||
2432 | do { | |
3528a953 CO |
2433 | if (*in_end == '"') |
2434 | open_quote = !open_quote; | |
2435 | if ((*in_end == ',' && open_quote == 0) || | |
2436 | *in_end == '\0') { | |
1da177e4 LT |
2437 | int len = in_end - in_curr; |
2438 | ||
2439 | if (selinux_option(in_curr, len)) | |
3528a953 | 2440 | take_selinux_option(&sec_curr, in_curr, &fsec, len); |
1da177e4 LT |
2441 | else |
2442 | take_option(&nosec, in_curr, &fnosec, len); | |
2443 | ||
2444 | in_curr = in_end + 1; | |
2445 | } | |
2446 | } while (*in_end++); | |
2447 | ||
6931dfc9 | 2448 | strcpy(in_save, nosec_save); |
da3caa20 | 2449 | free_page((unsigned long)nosec_save); |
1da177e4 LT |
2450 | out: |
2451 | return rc; | |
2452 | } | |
2453 | ||
2454 | static int selinux_sb_kern_mount(struct super_block *sb, void *data) | |
2455 | { | |
2456 | struct avc_audit_data ad; | |
2457 | int rc; | |
2458 | ||
2459 | rc = superblock_doinit(sb, data); | |
2460 | if (rc) | |
2461 | return rc; | |
2462 | ||
828dfe1d | 2463 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2464 | ad.u.fs.path.dentry = sb->s_root; |
1da177e4 LT |
2465 | return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); |
2466 | } | |
2467 | ||
726c3342 | 2468 | static int selinux_sb_statfs(struct dentry *dentry) |
1da177e4 LT |
2469 | { |
2470 | struct avc_audit_data ad; | |
2471 | ||
828dfe1d | 2472 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2473 | ad.u.fs.path.dentry = dentry->d_sb->s_root; |
726c3342 | 2474 | return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); |
1da177e4 LT |
2475 | } |
2476 | ||
828dfe1d | 2477 | static int selinux_mount(char *dev_name, |
b5266eb4 | 2478 | struct path *path, |
828dfe1d EP |
2479 | char *type, |
2480 | unsigned long flags, | |
2481 | void *data) | |
1da177e4 LT |
2482 | { |
2483 | int rc; | |
2484 | ||
b5266eb4 | 2485 | rc = secondary_ops->sb_mount(dev_name, path, type, flags, data); |
1da177e4 LT |
2486 | if (rc) |
2487 | return rc; | |
2488 | ||
2489 | if (flags & MS_REMOUNT) | |
b5266eb4 | 2490 | return superblock_has_perm(current, path->mnt->mnt_sb, |
828dfe1d | 2491 | FILESYSTEM__REMOUNT, NULL); |
1da177e4 | 2492 | else |
b5266eb4 | 2493 | return dentry_has_perm(current, path->mnt, path->dentry, |
828dfe1d | 2494 | FILE__MOUNTON); |
1da177e4 LT |
2495 | } |
2496 | ||
2497 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2498 | { | |
2499 | int rc; | |
2500 | ||
2501 | rc = secondary_ops->sb_umount(mnt, flags); | |
2502 | if (rc) | |
2503 | return rc; | |
2504 | ||
828dfe1d EP |
2505 | return superblock_has_perm(current, mnt->mnt_sb, |
2506 | FILESYSTEM__UNMOUNT, NULL); | |
1da177e4 LT |
2507 | } |
2508 | ||
2509 | /* inode security operations */ | |
2510 | ||
2511 | static int selinux_inode_alloc_security(struct inode *inode) | |
2512 | { | |
2513 | return inode_alloc_security(inode); | |
2514 | } | |
2515 | ||
2516 | static void selinux_inode_free_security(struct inode *inode) | |
2517 | { | |
2518 | inode_free_security(inode); | |
2519 | } | |
2520 | ||
5e41ff9e SS |
2521 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, |
2522 | char **name, void **value, | |
2523 | size_t *len) | |
2524 | { | |
2525 | struct task_security_struct *tsec; | |
2526 | struct inode_security_struct *dsec; | |
2527 | struct superblock_security_struct *sbsec; | |
570bc1c2 | 2528 | u32 newsid, clen; |
5e41ff9e | 2529 | int rc; |
570bc1c2 | 2530 | char *namep = NULL, *context; |
5e41ff9e SS |
2531 | |
2532 | tsec = current->security; | |
2533 | dsec = dir->i_security; | |
2534 | sbsec = dir->i_sb->s_security; | |
5e41ff9e SS |
2535 | |
2536 | if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { | |
2537 | newsid = tsec->create_sid; | |
2538 | } else { | |
2539 | rc = security_transition_sid(tsec->sid, dsec->sid, | |
2540 | inode_mode_to_security_class(inode->i_mode), | |
2541 | &newsid); | |
2542 | if (rc) { | |
2543 | printk(KERN_WARNING "%s: " | |
2544 | "security_transition_sid failed, rc=%d (dev=%s " | |
2545 | "ino=%ld)\n", | |
dd6f953a | 2546 | __func__, |
5e41ff9e SS |
2547 | -rc, inode->i_sb->s_id, inode->i_ino); |
2548 | return rc; | |
2549 | } | |
2550 | } | |
2551 | ||
296fddf7 EP |
2552 | /* Possibly defer initialization to selinux_complete_init. */ |
2553 | if (sbsec->initialized) { | |
2554 | struct inode_security_struct *isec = inode->i_security; | |
2555 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2556 | isec->sid = newsid; | |
2557 | isec->initialized = 1; | |
2558 | } | |
5e41ff9e | 2559 | |
8aad3875 | 2560 | if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) |
25a74f3b SS |
2561 | return -EOPNOTSUPP; |
2562 | ||
570bc1c2 | 2563 | if (name) { |
a02fe132 | 2564 | namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS); |
570bc1c2 SS |
2565 | if (!namep) |
2566 | return -ENOMEM; | |
2567 | *name = namep; | |
2568 | } | |
5e41ff9e | 2569 | |
570bc1c2 | 2570 | if (value && len) { |
12b29f34 | 2571 | rc = security_sid_to_context_force(newsid, &context, &clen); |
570bc1c2 SS |
2572 | if (rc) { |
2573 | kfree(namep); | |
2574 | return rc; | |
2575 | } | |
2576 | *value = context; | |
2577 | *len = clen; | |
5e41ff9e | 2578 | } |
5e41ff9e | 2579 | |
5e41ff9e SS |
2580 | return 0; |
2581 | } | |
2582 | ||
1da177e4 LT |
2583 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask) |
2584 | { | |
2585 | return may_create(dir, dentry, SECCLASS_FILE); | |
2586 | } | |
2587 | ||
1da177e4 LT |
2588 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) |
2589 | { | |
2590 | int rc; | |
2591 | ||
828dfe1d | 2592 | rc = secondary_ops->inode_link(old_dentry, dir, new_dentry); |
1da177e4 LT |
2593 | if (rc) |
2594 | return rc; | |
2595 | return may_link(dir, old_dentry, MAY_LINK); | |
2596 | } | |
2597 | ||
1da177e4 LT |
2598 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) |
2599 | { | |
2600 | int rc; | |
2601 | ||
2602 | rc = secondary_ops->inode_unlink(dir, dentry); | |
2603 | if (rc) | |
2604 | return rc; | |
2605 | return may_link(dir, dentry, MAY_UNLINK); | |
2606 | } | |
2607 | ||
2608 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2609 | { | |
2610 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2611 | } | |
2612 | ||
1da177e4 LT |
2613 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask) |
2614 | { | |
2615 | return may_create(dir, dentry, SECCLASS_DIR); | |
2616 | } | |
2617 | ||
1da177e4 LT |
2618 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) |
2619 | { | |
2620 | return may_link(dir, dentry, MAY_RMDIR); | |
2621 | } | |
2622 | ||
2623 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) | |
2624 | { | |
2625 | int rc; | |
2626 | ||
2627 | rc = secondary_ops->inode_mknod(dir, dentry, mode, dev); | |
2628 | if (rc) | |
2629 | return rc; | |
2630 | ||
2631 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); | |
2632 | } | |
2633 | ||
1da177e4 | 2634 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, |
828dfe1d | 2635 | struct inode *new_inode, struct dentry *new_dentry) |
1da177e4 LT |
2636 | { |
2637 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2638 | } | |
2639 | ||
1da177e4 LT |
2640 | static int selinux_inode_readlink(struct dentry *dentry) |
2641 | { | |
2642 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2643 | } | |
2644 | ||
2645 | static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata) | |
2646 | { | |
2647 | int rc; | |
2648 | ||
828dfe1d | 2649 | rc = secondary_ops->inode_follow_link(dentry, nameidata); |
1da177e4 LT |
2650 | if (rc) |
2651 | return rc; | |
2652 | return dentry_has_perm(current, NULL, dentry, FILE__READ); | |
2653 | } | |
2654 | ||
2655 | static int selinux_inode_permission(struct inode *inode, int mask, | |
2656 | struct nameidata *nd) | |
2657 | { | |
2658 | int rc; | |
2659 | ||
2660 | rc = secondary_ops->inode_permission(inode, mask, nd); | |
2661 | if (rc) | |
2662 | return rc; | |
2663 | ||
2664 | if (!mask) { | |
2665 | /* No permission to check. Existence test. */ | |
2666 | return 0; | |
2667 | } | |
2668 | ||
2669 | return inode_has_perm(current, inode, | |
b0c636b9 | 2670 | open_file_mask_to_av(inode->i_mode, mask), NULL); |
1da177e4 LT |
2671 | } |
2672 | ||
2673 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
2674 | { | |
2675 | int rc; | |
2676 | ||
2677 | rc = secondary_ops->inode_setattr(dentry, iattr); | |
2678 | if (rc) | |
2679 | return rc; | |
2680 | ||
2681 | if (iattr->ia_valid & ATTR_FORCE) | |
2682 | return 0; | |
2683 | ||
2684 | if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
2685 | ATTR_ATIME_SET | ATTR_MTIME_SET)) | |
2686 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2687 | ||
2688 | return dentry_has_perm(current, NULL, dentry, FILE__WRITE); | |
2689 | } | |
2690 | ||
2691 | static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
2692 | { | |
2693 | return dentry_has_perm(current, mnt, dentry, FILE__GETATTR); | |
2694 | } | |
2695 | ||
8f0cfa52 | 2696 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) |
b5376771 SH |
2697 | { |
2698 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
2699 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
2700 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
2701 | if (!capable(CAP_SETFCAP)) | |
2702 | return -EPERM; | |
2703 | } else if (!capable(CAP_SYS_ADMIN)) { | |
2704 | /* A different attribute in the security namespace. | |
2705 | Restrict to administrator. */ | |
2706 | return -EPERM; | |
2707 | } | |
2708 | } | |
2709 | ||
2710 | /* Not an attribute we recognize, so just check the | |
2711 | ordinary setattr permission. */ | |
2712 | return dentry_has_perm(current, NULL, dentry, FILE__SETATTR); | |
2713 | } | |
2714 | ||
8f0cfa52 DH |
2715 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, |
2716 | const void *value, size_t size, int flags) | |
1da177e4 LT |
2717 | { |
2718 | struct task_security_struct *tsec = current->security; | |
2719 | struct inode *inode = dentry->d_inode; | |
2720 | struct inode_security_struct *isec = inode->i_security; | |
2721 | struct superblock_security_struct *sbsec; | |
2722 | struct avc_audit_data ad; | |
2723 | u32 newsid; | |
2724 | int rc = 0; | |
2725 | ||
b5376771 SH |
2726 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2727 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2728 | |
2729 | sbsec = inode->i_sb->s_security; | |
2730 | if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT) | |
2731 | return -EOPNOTSUPP; | |
2732 | ||
3bd858ab | 2733 | if (!is_owner_or_cap(inode)) |
1da177e4 LT |
2734 | return -EPERM; |
2735 | ||
828dfe1d | 2736 | AVC_AUDIT_DATA_INIT(&ad, FS); |
44707fdf | 2737 | ad.u.fs.path.dentry = dentry; |
1da177e4 LT |
2738 | |
2739 | rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass, | |
2740 | FILE__RELABELFROM, &ad); | |
2741 | if (rc) | |
2742 | return rc; | |
2743 | ||
2744 | rc = security_context_to_sid(value, size, &newsid); | |
12b29f34 SS |
2745 | if (rc == -EINVAL) { |
2746 | if (!capable(CAP_MAC_ADMIN)) | |
2747 | return rc; | |
2748 | rc = security_context_to_sid_force(value, size, &newsid); | |
2749 | } | |
1da177e4 LT |
2750 | if (rc) |
2751 | return rc; | |
2752 | ||
2753 | rc = avc_has_perm(tsec->sid, newsid, isec->sclass, | |
2754 | FILE__RELABELTO, &ad); | |
2755 | if (rc) | |
2756 | return rc; | |
2757 | ||
2758 | rc = security_validate_transition(isec->sid, newsid, tsec->sid, | |
828dfe1d | 2759 | isec->sclass); |
1da177e4 LT |
2760 | if (rc) |
2761 | return rc; | |
2762 | ||
2763 | return avc_has_perm(newsid, | |
2764 | sbsec->sid, | |
2765 | SECCLASS_FILESYSTEM, | |
2766 | FILESYSTEM__ASSOCIATE, | |
2767 | &ad); | |
2768 | } | |
2769 | ||
8f0cfa52 | 2770 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, |
f5269710 | 2771 | const void *value, size_t size, |
8f0cfa52 | 2772 | int flags) |
1da177e4 LT |
2773 | { |
2774 | struct inode *inode = dentry->d_inode; | |
2775 | struct inode_security_struct *isec = inode->i_security; | |
2776 | u32 newsid; | |
2777 | int rc; | |
2778 | ||
2779 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
2780 | /* Not an attribute we recognize, so nothing to do. */ | |
2781 | return; | |
2782 | } | |
2783 | ||
12b29f34 | 2784 | rc = security_context_to_sid_force(value, size, &newsid); |
1da177e4 | 2785 | if (rc) { |
12b29f34 SS |
2786 | printk(KERN_ERR "SELinux: unable to map context to SID" |
2787 | "for (%s, %lu), rc=%d\n", | |
2788 | inode->i_sb->s_id, inode->i_ino, -rc); | |
1da177e4 LT |
2789 | return; |
2790 | } | |
2791 | ||
2792 | isec->sid = newsid; | |
2793 | return; | |
2794 | } | |
2795 | ||
8f0cfa52 | 2796 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) |
1da177e4 | 2797 | { |
1da177e4 LT |
2798 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); |
2799 | } | |
2800 | ||
828dfe1d | 2801 | static int selinux_inode_listxattr(struct dentry *dentry) |
1da177e4 LT |
2802 | { |
2803 | return dentry_has_perm(current, NULL, dentry, FILE__GETATTR); | |
2804 | } | |
2805 | ||
8f0cfa52 | 2806 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 2807 | { |
b5376771 SH |
2808 | if (strcmp(name, XATTR_NAME_SELINUX)) |
2809 | return selinux_inode_setotherxattr(dentry, name); | |
1da177e4 LT |
2810 | |
2811 | /* No one is allowed to remove a SELinux security label. | |
2812 | You can change the label, but all data must be labeled. */ | |
2813 | return -EACCES; | |
2814 | } | |
2815 | ||
d381d8a9 | 2816 | /* |
abc69bb6 | 2817 | * Copy the inode security context value to the user. |
d381d8a9 JM |
2818 | * |
2819 | * Permission check is handled by selinux_inode_getxattr hook. | |
2820 | */ | |
42492594 | 2821 | static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc) |
1da177e4 | 2822 | { |
42492594 DQ |
2823 | u32 size; |
2824 | int error; | |
2825 | char *context = NULL; | |
abc69bb6 | 2826 | struct task_security_struct *tsec = current->security; |
1da177e4 | 2827 | struct inode_security_struct *isec = inode->i_security; |
d381d8a9 | 2828 | |
8c8570fb DK |
2829 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) |
2830 | return -EOPNOTSUPP; | |
d381d8a9 | 2831 | |
abc69bb6 SS |
2832 | /* |
2833 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
2834 | * value even if it is not defined by current policy; otherwise, | |
2835 | * use the in-core value under current policy. | |
2836 | * Use the non-auditing forms of the permission checks since | |
2837 | * getxattr may be called by unprivileged processes commonly | |
2838 | * and lack of permission just means that we fall back to the | |
2839 | * in-core context value, not a denial. | |
2840 | */ | |
2841 | error = secondary_ops->capable(current, CAP_MAC_ADMIN); | |
2842 | if (!error) | |
2843 | error = avc_has_perm_noaudit(tsec->sid, tsec->sid, | |
2844 | SECCLASS_CAPABILITY2, | |
2845 | CAPABILITY2__MAC_ADMIN, | |
2846 | 0, | |
2847 | NULL); | |
2848 | if (!error) | |
2849 | error = security_sid_to_context_force(isec->sid, &context, | |
2850 | &size); | |
2851 | else | |
2852 | error = security_sid_to_context(isec->sid, &context, &size); | |
42492594 DQ |
2853 | if (error) |
2854 | return error; | |
2855 | error = size; | |
2856 | if (alloc) { | |
2857 | *buffer = context; | |
2858 | goto out_nofree; | |
2859 | } | |
2860 | kfree(context); | |
2861 | out_nofree: | |
2862 | return error; | |
1da177e4 LT |
2863 | } |
2864 | ||
2865 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
828dfe1d | 2866 | const void *value, size_t size, int flags) |
1da177e4 LT |
2867 | { |
2868 | struct inode_security_struct *isec = inode->i_security; | |
2869 | u32 newsid; | |
2870 | int rc; | |
2871 | ||
2872 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
2873 | return -EOPNOTSUPP; | |
2874 | ||
2875 | if (!value || !size) | |
2876 | return -EACCES; | |
2877 | ||
828dfe1d | 2878 | rc = security_context_to_sid((void *)value, size, &newsid); |
1da177e4 LT |
2879 | if (rc) |
2880 | return rc; | |
2881 | ||
2882 | isec->sid = newsid; | |
2883 | return 0; | |
2884 | } | |
2885 | ||
2886 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
2887 | { | |
2888 | const int len = sizeof(XATTR_NAME_SELINUX); | |
2889 | if (buffer && len <= buffer_size) | |
2890 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
2891 | return len; | |
2892 | } | |
2893 | ||
b5376771 SH |
2894 | static int selinux_inode_need_killpriv(struct dentry *dentry) |
2895 | { | |
2896 | return secondary_ops->inode_need_killpriv(dentry); | |
2897 | } | |
2898 | ||
2899 | static int selinux_inode_killpriv(struct dentry *dentry) | |
2900 | { | |
2901 | return secondary_ops->inode_killpriv(dentry); | |
2902 | } | |
2903 | ||
713a04ae AD |
2904 | static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) |
2905 | { | |
2906 | struct inode_security_struct *isec = inode->i_security; | |
2907 | *secid = isec->sid; | |
2908 | } | |
2909 | ||
1da177e4 LT |
2910 | /* file security operations */ |
2911 | ||
788e7dd4 | 2912 | static int selinux_revalidate_file_permission(struct file *file, int mask) |
1da177e4 | 2913 | { |
7420ed23 | 2914 | int rc; |
3d5ff529 | 2915 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
2916 | |
2917 | if (!mask) { | |
2918 | /* No permission to check. Existence test. */ | |
2919 | return 0; | |
2920 | } | |
2921 | ||
2922 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
2923 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
2924 | mask |= MAY_APPEND; | |
2925 | ||
7420ed23 VY |
2926 | rc = file_has_perm(current, file, |
2927 | file_mask_to_av(inode->i_mode, mask)); | |
2928 | if (rc) | |
2929 | return rc; | |
2930 | ||
2931 | return selinux_netlbl_inode_permission(inode, mask); | |
1da177e4 LT |
2932 | } |
2933 | ||
788e7dd4 YN |
2934 | static int selinux_file_permission(struct file *file, int mask) |
2935 | { | |
2936 | struct inode *inode = file->f_path.dentry->d_inode; | |
2937 | struct task_security_struct *tsec = current->security; | |
2938 | struct file_security_struct *fsec = file->f_security; | |
2939 | struct inode_security_struct *isec = inode->i_security; | |
2940 | ||
2941 | if (!mask) { | |
2942 | /* No permission to check. Existence test. */ | |
2943 | return 0; | |
2944 | } | |
2945 | ||
2946 | if (tsec->sid == fsec->sid && fsec->isid == isec->sid | |
2947 | && fsec->pseqno == avc_policy_seqno()) | |
2948 | return selinux_netlbl_inode_permission(inode, mask); | |
2949 | ||
2950 | return selinux_revalidate_file_permission(file, mask); | |
2951 | } | |
2952 | ||
1da177e4 LT |
2953 | static int selinux_file_alloc_security(struct file *file) |
2954 | { | |
2955 | return file_alloc_security(file); | |
2956 | } | |
2957 | ||
2958 | static void selinux_file_free_security(struct file *file) | |
2959 | { | |
2960 | file_free_security(file); | |
2961 | } | |
2962 | ||
2963 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
2964 | unsigned long arg) | |
2965 | { | |
242631c4 | 2966 | u32 av = 0; |
1da177e4 | 2967 | |
242631c4 SS |
2968 | if (_IOC_DIR(cmd) & _IOC_WRITE) |
2969 | av |= FILE__WRITE; | |
2970 | if (_IOC_DIR(cmd) & _IOC_READ) | |
2971 | av |= FILE__READ; | |
2972 | if (!av) | |
2973 | av = FILE__IOCTL; | |
1da177e4 | 2974 | |
242631c4 | 2975 | return file_has_perm(current, file, av); |
1da177e4 LT |
2976 | } |
2977 | ||
2978 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
2979 | { | |
2980 | #ifndef CONFIG_PPC32 | |
2981 | if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) { | |
2982 | /* | |
2983 | * We are making executable an anonymous mapping or a | |
2984 | * private file mapping that will also be writable. | |
2985 | * This has an additional check. | |
2986 | */ | |
2987 | int rc = task_has_perm(current, current, PROCESS__EXECMEM); | |
2988 | if (rc) | |
2989 | return rc; | |
2990 | } | |
2991 | #endif | |
2992 | ||
2993 | if (file) { | |
2994 | /* read access is always possible with a mapping */ | |
2995 | u32 av = FILE__READ; | |
2996 | ||
2997 | /* write access only matters if the mapping is shared */ | |
2998 | if (shared && (prot & PROT_WRITE)) | |
2999 | av |= FILE__WRITE; | |
3000 | ||
3001 | if (prot & PROT_EXEC) | |
3002 | av |= FILE__EXECUTE; | |
3003 | ||
3004 | return file_has_perm(current, file, av); | |
3005 | } | |
3006 | return 0; | |
3007 | } | |
3008 | ||
3009 | static int selinux_file_mmap(struct file *file, unsigned long reqprot, | |
ed032189 EP |
3010 | unsigned long prot, unsigned long flags, |
3011 | unsigned long addr, unsigned long addr_only) | |
1da177e4 | 3012 | { |
ed032189 | 3013 | int rc = 0; |
828dfe1d | 3014 | u32 sid = ((struct task_security_struct *)(current->security))->sid; |
1da177e4 | 3015 | |
ed032189 EP |
3016 | if (addr < mmap_min_addr) |
3017 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, | |
3018 | MEMPROTECT__MMAP_ZERO, NULL); | |
3019 | if (rc || addr_only) | |
1da177e4 LT |
3020 | return rc; |
3021 | ||
3022 | if (selinux_checkreqprot) | |
3023 | prot = reqprot; | |
3024 | ||
3025 | return file_map_prot_check(file, prot, | |
3026 | (flags & MAP_TYPE) == MAP_SHARED); | |
3027 | } | |
3028 | ||
3029 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3030 | unsigned long reqprot, | |
3031 | unsigned long prot) | |
3032 | { | |
3033 | int rc; | |
3034 | ||
3035 | rc = secondary_ops->file_mprotect(vma, reqprot, prot); | |
3036 | if (rc) | |
3037 | return rc; | |
3038 | ||
3039 | if (selinux_checkreqprot) | |
3040 | prot = reqprot; | |
3041 | ||
3042 | #ifndef CONFIG_PPC32 | |
db4c9641 SS |
3043 | if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { |
3044 | rc = 0; | |
3045 | if (vma->vm_start >= vma->vm_mm->start_brk && | |
3046 | vma->vm_end <= vma->vm_mm->brk) { | |
3047 | rc = task_has_perm(current, current, | |
3048 | PROCESS__EXECHEAP); | |
3049 | } else if (!vma->vm_file && | |
3050 | vma->vm_start <= vma->vm_mm->start_stack && | |
3051 | vma->vm_end >= vma->vm_mm->start_stack) { | |
3052 | rc = task_has_perm(current, current, PROCESS__EXECSTACK); | |
3053 | } else if (vma->vm_file && vma->anon_vma) { | |
3054 | /* | |
3055 | * We are making executable a file mapping that has | |
3056 | * had some COW done. Since pages might have been | |
3057 | * written, check ability to execute the possibly | |
3058 | * modified content. This typically should only | |
3059 | * occur for text relocations. | |
3060 | */ | |
3061 | rc = file_has_perm(current, vma->vm_file, | |
3062 | FILE__EXECMOD); | |
3063 | } | |