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1 | /* | |
2 | * NSA Security-Enhanced Linux (SELinux) security module | |
3 | * | |
4 | * This file contains the SELinux hook function implementations. | |
5 | * | |
6 | * Authors: Stephen Smalley, <sds@epoch.ncsc.mil> | |
7 | * Chris Vance, <cvance@nai.com> | |
8 | * Wayne Salamon, <wsalamon@nai.com> | |
9 | * James Morris <jmorris@redhat.com> | |
10 | * | |
11 | * Copyright (C) 2001,2002 Networks Associates Technology, Inc. | |
12 | * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com> | |
13 | * Eric Paris <eparis@redhat.com> | |
14 | * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. | |
15 | * <dgoeddel@trustedcs.com> | |
16 | * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P. | |
17 | * Paul Moore <paul@paul-moore.com> | |
18 | * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd. | |
19 | * Yuichi Nakamura <ynakam@hitachisoft.jp> | |
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, | |
23 | * as published by the Free Software Foundation. | |
24 | */ | |
25 | ||
26 | #include <linux/init.h> | |
27 | #include <linux/kd.h> | |
28 | #include <linux/kernel.h> | |
29 | #include <linux/tracehook.h> | |
30 | #include <linux/errno.h> | |
31 | #include <linux/sched.h> | |
32 | #include <linux/lsm_hooks.h> | |
33 | #include <linux/xattr.h> | |
34 | #include <linux/capability.h> | |
35 | #include <linux/unistd.h> | |
36 | #include <linux/mm.h> | |
37 | #include <linux/mman.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/pagemap.h> | |
40 | #include <linux/proc_fs.h> | |
41 | #include <linux/swap.h> | |
42 | #include <linux/spinlock.h> | |
43 | #include <linux/syscalls.h> | |
44 | #include <linux/dcache.h> | |
45 | #include <linux/file.h> | |
46 | #include <linux/fdtable.h> | |
47 | #include <linux/namei.h> | |
48 | #include <linux/mount.h> | |
49 | #include <linux/netfilter_ipv4.h> | |
50 | #include <linux/netfilter_ipv6.h> | |
51 | #include <linux/tty.h> | |
52 | #include <net/icmp.h> | |
53 | #include <net/ip.h> /* for local_port_range[] */ | |
54 | #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */ | |
55 | #include <net/inet_connection_sock.h> | |
56 | #include <net/net_namespace.h> | |
57 | #include <net/netlabel.h> | |
58 | #include <linux/uaccess.h> | |
59 | #include <asm/ioctls.h> | |
60 | #include <linux/atomic.h> | |
61 | #include <linux/bitops.h> | |
62 | #include <linux/interrupt.h> | |
63 | #include <linux/netdevice.h> /* for network interface checks */ | |
64 | #include <net/netlink.h> | |
65 | #include <linux/tcp.h> | |
66 | #include <linux/udp.h> | |
67 | #include <linux/dccp.h> | |
68 | #include <linux/quota.h> | |
69 | #include <linux/un.h> /* for Unix socket types */ | |
70 | #include <net/af_unix.h> /* for Unix socket types */ | |
71 | #include <linux/parser.h> | |
72 | #include <linux/nfs_mount.h> | |
73 | #include <net/ipv6.h> | |
74 | #include <linux/hugetlb.h> | |
75 | #include <linux/personality.h> | |
76 | #include <linux/audit.h> | |
77 | #include <linux/string.h> | |
78 | #include <linux/selinux.h> | |
79 | #include <linux/mutex.h> | |
80 | #include <linux/posix-timers.h> | |
81 | #include <linux/syslog.h> | |
82 | #include <linux/user_namespace.h> | |
83 | #include <linux/export.h> | |
84 | #include <linux/msg.h> | |
85 | #include <linux/shm.h> | |
86 | ||
87 | #include "avc.h" | |
88 | #include "objsec.h" | |
89 | #include "netif.h" | |
90 | #include "netnode.h" | |
91 | #include "netport.h" | |
92 | #include "xfrm.h" | |
93 | #include "netlabel.h" | |
94 | #include "audit.h" | |
95 | #include "avc_ss.h" | |
96 | ||
97 | /* SECMARK reference count */ | |
98 | static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); | |
99 | ||
100 | #ifdef CONFIG_SECURITY_SELINUX_DEVELOP | |
101 | int selinux_enforcing; | |
102 | ||
103 | static int __init enforcing_setup(char *str) | |
104 | { | |
105 | unsigned long enforcing; | |
106 | if (!kstrtoul(str, 0, &enforcing)) | |
107 | selinux_enforcing = enforcing ? 1 : 0; | |
108 | return 1; | |
109 | } | |
110 | __setup("enforcing=", enforcing_setup); | |
111 | #endif | |
112 | ||
113 | #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM | |
114 | int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; | |
115 | ||
116 | static int __init selinux_enabled_setup(char *str) | |
117 | { | |
118 | unsigned long enabled; | |
119 | if (!kstrtoul(str, 0, &enabled)) | |
120 | selinux_enabled = enabled ? 1 : 0; | |
121 | return 1; | |
122 | } | |
123 | __setup("selinux=", selinux_enabled_setup); | |
124 | #else | |
125 | int selinux_enabled = 1; | |
126 | #endif | |
127 | ||
128 | static struct kmem_cache *sel_inode_cache; | |
129 | static struct kmem_cache *file_security_cache; | |
130 | ||
131 | /** | |
132 | * selinux_secmark_enabled - Check to see if SECMARK is currently enabled | |
133 | * | |
134 | * Description: | |
135 | * This function checks the SECMARK reference counter to see if any SECMARK | |
136 | * targets are currently configured, if the reference counter is greater than | |
137 | * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is | |
138 | * enabled, false (0) if SECMARK is disabled. If the always_check_network | |
139 | * policy capability is enabled, SECMARK is always considered enabled. | |
140 | * | |
141 | */ | |
142 | static int selinux_secmark_enabled(void) | |
143 | { | |
144 | return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); | |
145 | } | |
146 | ||
147 | /** | |
148 | * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled | |
149 | * | |
150 | * Description: | |
151 | * This function checks if NetLabel or labeled IPSEC is enabled. Returns true | |
152 | * (1) if any are enabled or false (0) if neither are enabled. If the | |
153 | * always_check_network policy capability is enabled, peer labeling | |
154 | * is always considered enabled. | |
155 | * | |
156 | */ | |
157 | static int selinux_peerlbl_enabled(void) | |
158 | { | |
159 | return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled()); | |
160 | } | |
161 | ||
162 | static int selinux_netcache_avc_callback(u32 event) | |
163 | { | |
164 | if (event == AVC_CALLBACK_RESET) { | |
165 | sel_netif_flush(); | |
166 | sel_netnode_flush(); | |
167 | sel_netport_flush(); | |
168 | synchronize_net(); | |
169 | } | |
170 | return 0; | |
171 | } | |
172 | ||
173 | /* | |
174 | * initialise the security for the init task | |
175 | */ | |
176 | static void cred_init_security(void) | |
177 | { | |
178 | struct cred *cred = (struct cred *) current->real_cred; | |
179 | struct task_security_struct *tsec; | |
180 | ||
181 | tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL); | |
182 | if (!tsec) | |
183 | panic("SELinux: Failed to initialize initial task.\n"); | |
184 | ||
185 | tsec->osid = tsec->sid = SECINITSID_KERNEL; | |
186 | cred->security = tsec; | |
187 | } | |
188 | ||
189 | /* | |
190 | * get the security ID of a set of credentials | |
191 | */ | |
192 | static inline u32 cred_sid(const struct cred *cred) | |
193 | { | |
194 | const struct task_security_struct *tsec; | |
195 | ||
196 | tsec = cred->security; | |
197 | return tsec->sid; | |
198 | } | |
199 | ||
200 | /* | |
201 | * get the objective security ID of a task | |
202 | */ | |
203 | static inline u32 task_sid(const struct task_struct *task) | |
204 | { | |
205 | u32 sid; | |
206 | ||
207 | rcu_read_lock(); | |
208 | sid = cred_sid(__task_cred(task)); | |
209 | rcu_read_unlock(); | |
210 | return sid; | |
211 | } | |
212 | ||
213 | /* Allocate and free functions for each kind of security blob. */ | |
214 | ||
215 | static int inode_alloc_security(struct inode *inode) | |
216 | { | |
217 | struct inode_security_struct *isec; | |
218 | u32 sid = current_sid(); | |
219 | ||
220 | isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS); | |
221 | if (!isec) | |
222 | return -ENOMEM; | |
223 | ||
224 | spin_lock_init(&isec->lock); | |
225 | INIT_LIST_HEAD(&isec->list); | |
226 | isec->inode = inode; | |
227 | isec->sid = SECINITSID_UNLABELED; | |
228 | isec->sclass = SECCLASS_FILE; | |
229 | isec->task_sid = sid; | |
230 | isec->initialized = LABEL_INVALID; | |
231 | inode->i_security = isec; | |
232 | ||
233 | return 0; | |
234 | } | |
235 | ||
236 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry); | |
237 | ||
238 | /* | |
239 | * Try reloading inode security labels that have been marked as invalid. The | |
240 | * @may_sleep parameter indicates when sleeping and thus reloading labels is | |
241 | * allowed; when set to false, returns -ECHILD when the label is | |
242 | * invalid. The @opt_dentry parameter should be set to a dentry of the inode; | |
243 | * when no dentry is available, set it to NULL instead. | |
244 | */ | |
245 | static int __inode_security_revalidate(struct inode *inode, | |
246 | struct dentry *opt_dentry, | |
247 | bool may_sleep) | |
248 | { | |
249 | struct inode_security_struct *isec = inode->i_security; | |
250 | ||
251 | might_sleep_if(may_sleep); | |
252 | ||
253 | if (ss_initialized && isec->initialized != LABEL_INITIALIZED) { | |
254 | if (!may_sleep) | |
255 | return -ECHILD; | |
256 | ||
257 | /* | |
258 | * Try reloading the inode security label. This will fail if | |
259 | * @opt_dentry is NULL and no dentry for this inode can be | |
260 | * found; in that case, continue using the old label. | |
261 | */ | |
262 | inode_doinit_with_dentry(inode, opt_dentry); | |
263 | } | |
264 | return 0; | |
265 | } | |
266 | ||
267 | static struct inode_security_struct *inode_security_novalidate(struct inode *inode) | |
268 | { | |
269 | return inode->i_security; | |
270 | } | |
271 | ||
272 | static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu) | |
273 | { | |
274 | int error; | |
275 | ||
276 | error = __inode_security_revalidate(inode, NULL, !rcu); | |
277 | if (error) | |
278 | return ERR_PTR(error); | |
279 | return inode->i_security; | |
280 | } | |
281 | ||
282 | /* | |
283 | * Get the security label of an inode. | |
284 | */ | |
285 | static struct inode_security_struct *inode_security(struct inode *inode) | |
286 | { | |
287 | __inode_security_revalidate(inode, NULL, true); | |
288 | return inode->i_security; | |
289 | } | |
290 | ||
291 | static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry) | |
292 | { | |
293 | struct inode *inode = d_backing_inode(dentry); | |
294 | ||
295 | return inode->i_security; | |
296 | } | |
297 | ||
298 | /* | |
299 | * Get the security label of a dentry's backing inode. | |
300 | */ | |
301 | static struct inode_security_struct *backing_inode_security(struct dentry *dentry) | |
302 | { | |
303 | struct inode *inode = d_backing_inode(dentry); | |
304 | ||
305 | __inode_security_revalidate(inode, dentry, true); | |
306 | return inode->i_security; | |
307 | } | |
308 | ||
309 | static void inode_free_rcu(struct rcu_head *head) | |
310 | { | |
311 | struct inode_security_struct *isec; | |
312 | ||
313 | isec = container_of(head, struct inode_security_struct, rcu); | |
314 | kmem_cache_free(sel_inode_cache, isec); | |
315 | } | |
316 | ||
317 | static void inode_free_security(struct inode *inode) | |
318 | { | |
319 | struct inode_security_struct *isec = inode->i_security; | |
320 | struct superblock_security_struct *sbsec = inode->i_sb->s_security; | |
321 | ||
322 | /* | |
323 | * As not all inode security structures are in a list, we check for | |
324 | * empty list outside of the lock to make sure that we won't waste | |
325 | * time taking a lock doing nothing. | |
326 | * | |
327 | * The list_del_init() function can be safely called more than once. | |
328 | * It should not be possible for this function to be called with | |
329 | * concurrent list_add(), but for better safety against future changes | |
330 | * in the code, we use list_empty_careful() here. | |
331 | */ | |
332 | if (!list_empty_careful(&isec->list)) { | |
333 | spin_lock(&sbsec->isec_lock); | |
334 | list_del_init(&isec->list); | |
335 | spin_unlock(&sbsec->isec_lock); | |
336 | } | |
337 | ||
338 | /* | |
339 | * The inode may still be referenced in a path walk and | |
340 | * a call to selinux_inode_permission() can be made | |
341 | * after inode_free_security() is called. Ideally, the VFS | |
342 | * wouldn't do this, but fixing that is a much harder | |
343 | * job. For now, simply free the i_security via RCU, and | |
344 | * leave the current inode->i_security pointer intact. | |
345 | * The inode will be freed after the RCU grace period too. | |
346 | */ | |
347 | call_rcu(&isec->rcu, inode_free_rcu); | |
348 | } | |
349 | ||
350 | static int file_alloc_security(struct file *file) | |
351 | { | |
352 | struct file_security_struct *fsec; | |
353 | u32 sid = current_sid(); | |
354 | ||
355 | fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL); | |
356 | if (!fsec) | |
357 | return -ENOMEM; | |
358 | ||
359 | fsec->sid = sid; | |
360 | fsec->fown_sid = sid; | |
361 | file->f_security = fsec; | |
362 | ||
363 | return 0; | |
364 | } | |
365 | ||
366 | static void file_free_security(struct file *file) | |
367 | { | |
368 | struct file_security_struct *fsec = file->f_security; | |
369 | file->f_security = NULL; | |
370 | kmem_cache_free(file_security_cache, fsec); | |
371 | } | |
372 | ||
373 | static int superblock_alloc_security(struct super_block *sb) | |
374 | { | |
375 | struct superblock_security_struct *sbsec; | |
376 | ||
377 | sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL); | |
378 | if (!sbsec) | |
379 | return -ENOMEM; | |
380 | ||
381 | mutex_init(&sbsec->lock); | |
382 | INIT_LIST_HEAD(&sbsec->isec_head); | |
383 | spin_lock_init(&sbsec->isec_lock); | |
384 | sbsec->sb = sb; | |
385 | sbsec->sid = SECINITSID_UNLABELED; | |
386 | sbsec->def_sid = SECINITSID_FILE; | |
387 | sbsec->mntpoint_sid = SECINITSID_UNLABELED; | |
388 | sb->s_security = sbsec; | |
389 | ||
390 | return 0; | |
391 | } | |
392 | ||
393 | static void superblock_free_security(struct super_block *sb) | |
394 | { | |
395 | struct superblock_security_struct *sbsec = sb->s_security; | |
396 | sb->s_security = NULL; | |
397 | kfree(sbsec); | |
398 | } | |
399 | ||
400 | /* The file system's label must be initialized prior to use. */ | |
401 | ||
402 | static const char *labeling_behaviors[7] = { | |
403 | "uses xattr", | |
404 | "uses transition SIDs", | |
405 | "uses task SIDs", | |
406 | "uses genfs_contexts", | |
407 | "not configured for labeling", | |
408 | "uses mountpoint labeling", | |
409 | "uses native labeling", | |
410 | }; | |
411 | ||
412 | static inline int inode_doinit(struct inode *inode) | |
413 | { | |
414 | return inode_doinit_with_dentry(inode, NULL); | |
415 | } | |
416 | ||
417 | enum { | |
418 | Opt_error = -1, | |
419 | Opt_context = 1, | |
420 | Opt_fscontext = 2, | |
421 | Opt_defcontext = 3, | |
422 | Opt_rootcontext = 4, | |
423 | Opt_labelsupport = 5, | |
424 | Opt_nextmntopt = 6, | |
425 | }; | |
426 | ||
427 | #define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1) | |
428 | ||
429 | static const match_table_t tokens = { | |
430 | {Opt_context, CONTEXT_STR "%s"}, | |
431 | {Opt_fscontext, FSCONTEXT_STR "%s"}, | |
432 | {Opt_defcontext, DEFCONTEXT_STR "%s"}, | |
433 | {Opt_rootcontext, ROOTCONTEXT_STR "%s"}, | |
434 | {Opt_labelsupport, LABELSUPP_STR}, | |
435 | {Opt_error, NULL}, | |
436 | }; | |
437 | ||
438 | #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n" | |
439 | ||
440 | static int may_context_mount_sb_relabel(u32 sid, | |
441 | struct superblock_security_struct *sbsec, | |
442 | const struct cred *cred) | |
443 | { | |
444 | const struct task_security_struct *tsec = cred->security; | |
445 | int rc; | |
446 | ||
447 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
448 | FILESYSTEM__RELABELFROM, NULL); | |
449 | if (rc) | |
450 | return rc; | |
451 | ||
452 | rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM, | |
453 | FILESYSTEM__RELABELTO, NULL); | |
454 | return rc; | |
455 | } | |
456 | ||
457 | static int may_context_mount_inode_relabel(u32 sid, | |
458 | struct superblock_security_struct *sbsec, | |
459 | const struct cred *cred) | |
460 | { | |
461 | const struct task_security_struct *tsec = cred->security; | |
462 | int rc; | |
463 | rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
464 | FILESYSTEM__RELABELFROM, NULL); | |
465 | if (rc) | |
466 | return rc; | |
467 | ||
468 | rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, | |
469 | FILESYSTEM__ASSOCIATE, NULL); | |
470 | return rc; | |
471 | } | |
472 | ||
473 | static int selinux_is_sblabel_mnt(struct super_block *sb) | |
474 | { | |
475 | struct superblock_security_struct *sbsec = sb->s_security; | |
476 | ||
477 | return sbsec->behavior == SECURITY_FS_USE_XATTR || | |
478 | sbsec->behavior == SECURITY_FS_USE_TRANS || | |
479 | sbsec->behavior == SECURITY_FS_USE_TASK || | |
480 | sbsec->behavior == SECURITY_FS_USE_NATIVE || | |
481 | /* Special handling. Genfs but also in-core setxattr handler */ | |
482 | !strcmp(sb->s_type->name, "sysfs") || | |
483 | !strcmp(sb->s_type->name, "cgroup") || | |
484 | !strcmp(sb->s_type->name, "cgroup2") || | |
485 | !strcmp(sb->s_type->name, "pstore") || | |
486 | !strcmp(sb->s_type->name, "debugfs") || | |
487 | !strcmp(sb->s_type->name, "tracefs") || | |
488 | !strcmp(sb->s_type->name, "rootfs"); | |
489 | } | |
490 | ||
491 | static int sb_finish_set_opts(struct super_block *sb) | |
492 | { | |
493 | struct superblock_security_struct *sbsec = sb->s_security; | |
494 | struct dentry *root = sb->s_root; | |
495 | struct inode *root_inode = d_backing_inode(root); | |
496 | int rc = 0; | |
497 | ||
498 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
499 | /* Make sure that the xattr handler exists and that no | |
500 | error other than -ENODATA is returned by getxattr on | |
501 | the root directory. -ENODATA is ok, as this may be | |
502 | the first boot of the SELinux kernel before we have | |
503 | assigned xattr values to the filesystem. */ | |
504 | if (!(root_inode->i_opflags & IOP_XATTR)) { | |
505 | printk(KERN_WARNING "SELinux: (dev %s, type %s) has no " | |
506 | "xattr support\n", sb->s_id, sb->s_type->name); | |
507 | rc = -EOPNOTSUPP; | |
508 | goto out; | |
509 | } | |
510 | ||
511 | rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); | |
512 | if (rc < 0 && rc != -ENODATA) { | |
513 | if (rc == -EOPNOTSUPP) | |
514 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
515 | "%s) has no security xattr handler\n", | |
516 | sb->s_id, sb->s_type->name); | |
517 | else | |
518 | printk(KERN_WARNING "SELinux: (dev %s, type " | |
519 | "%s) getxattr errno %d\n", sb->s_id, | |
520 | sb->s_type->name, -rc); | |
521 | goto out; | |
522 | } | |
523 | } | |
524 | ||
525 | if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) | |
526 | printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n", | |
527 | sb->s_id, sb->s_type->name); | |
528 | ||
529 | sbsec->flags |= SE_SBINITIALIZED; | |
530 | if (selinux_is_sblabel_mnt(sb)) | |
531 | sbsec->flags |= SBLABEL_MNT; | |
532 | ||
533 | /* Initialize the root inode. */ | |
534 | rc = inode_doinit_with_dentry(root_inode, root); | |
535 | ||
536 | /* Initialize any other inodes associated with the superblock, e.g. | |
537 | inodes created prior to initial policy load or inodes created | |
538 | during get_sb by a pseudo filesystem that directly | |
539 | populates itself. */ | |
540 | spin_lock(&sbsec->isec_lock); | |
541 | next_inode: | |
542 | if (!list_empty(&sbsec->isec_head)) { | |
543 | struct inode_security_struct *isec = | |
544 | list_entry(sbsec->isec_head.next, | |
545 | struct inode_security_struct, list); | |
546 | struct inode *inode = isec->inode; | |
547 | list_del_init(&isec->list); | |
548 | spin_unlock(&sbsec->isec_lock); | |
549 | inode = igrab(inode); | |
550 | if (inode) { | |
551 | if (!IS_PRIVATE(inode)) | |
552 | inode_doinit(inode); | |
553 | iput(inode); | |
554 | } | |
555 | spin_lock(&sbsec->isec_lock); | |
556 | goto next_inode; | |
557 | } | |
558 | spin_unlock(&sbsec->isec_lock); | |
559 | out: | |
560 | return rc; | |
561 | } | |
562 | ||
563 | /* | |
564 | * This function should allow an FS to ask what it's mount security | |
565 | * options were so it can use those later for submounts, displaying | |
566 | * mount options, or whatever. | |
567 | */ | |
568 | static int selinux_get_mnt_opts(const struct super_block *sb, | |
569 | struct security_mnt_opts *opts) | |
570 | { | |
571 | int rc = 0, i; | |
572 | struct superblock_security_struct *sbsec = sb->s_security; | |
573 | char *context = NULL; | |
574 | u32 len; | |
575 | char tmp; | |
576 | ||
577 | security_init_mnt_opts(opts); | |
578 | ||
579 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
580 | return -EINVAL; | |
581 | ||
582 | if (!ss_initialized) | |
583 | return -EINVAL; | |
584 | ||
585 | /* make sure we always check enough bits to cover the mask */ | |
586 | BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS)); | |
587 | ||
588 | tmp = sbsec->flags & SE_MNTMASK; | |
589 | /* count the number of mount options for this sb */ | |
590 | for (i = 0; i < NUM_SEL_MNT_OPTS; i++) { | |
591 | if (tmp & 0x01) | |
592 | opts->num_mnt_opts++; | |
593 | tmp >>= 1; | |
594 | } | |
595 | /* Check if the Label support flag is set */ | |
596 | if (sbsec->flags & SBLABEL_MNT) | |
597 | opts->num_mnt_opts++; | |
598 | ||
599 | opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC); | |
600 | if (!opts->mnt_opts) { | |
601 | rc = -ENOMEM; | |
602 | goto out_free; | |
603 | } | |
604 | ||
605 | opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC); | |
606 | if (!opts->mnt_opts_flags) { | |
607 | rc = -ENOMEM; | |
608 | goto out_free; | |
609 | } | |
610 | ||
611 | i = 0; | |
612 | if (sbsec->flags & FSCONTEXT_MNT) { | |
613 | rc = security_sid_to_context(sbsec->sid, &context, &len); | |
614 | if (rc) | |
615 | goto out_free; | |
616 | opts->mnt_opts[i] = context; | |
617 | opts->mnt_opts_flags[i++] = FSCONTEXT_MNT; | |
618 | } | |
619 | if (sbsec->flags & CONTEXT_MNT) { | |
620 | rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len); | |
621 | if (rc) | |
622 | goto out_free; | |
623 | opts->mnt_opts[i] = context; | |
624 | opts->mnt_opts_flags[i++] = CONTEXT_MNT; | |
625 | } | |
626 | if (sbsec->flags & DEFCONTEXT_MNT) { | |
627 | rc = security_sid_to_context(sbsec->def_sid, &context, &len); | |
628 | if (rc) | |
629 | goto out_free; | |
630 | opts->mnt_opts[i] = context; | |
631 | opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT; | |
632 | } | |
633 | if (sbsec->flags & ROOTCONTEXT_MNT) { | |
634 | struct dentry *root = sbsec->sb->s_root; | |
635 | struct inode_security_struct *isec = backing_inode_security(root); | |
636 | ||
637 | rc = security_sid_to_context(isec->sid, &context, &len); | |
638 | if (rc) | |
639 | goto out_free; | |
640 | opts->mnt_opts[i] = context; | |
641 | opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT; | |
642 | } | |
643 | if (sbsec->flags & SBLABEL_MNT) { | |
644 | opts->mnt_opts[i] = NULL; | |
645 | opts->mnt_opts_flags[i++] = SBLABEL_MNT; | |
646 | } | |
647 | ||
648 | BUG_ON(i != opts->num_mnt_opts); | |
649 | ||
650 | return 0; | |
651 | ||
652 | out_free: | |
653 | security_free_mnt_opts(opts); | |
654 | return rc; | |
655 | } | |
656 | ||
657 | static int bad_option(struct superblock_security_struct *sbsec, char flag, | |
658 | u32 old_sid, u32 new_sid) | |
659 | { | |
660 | char mnt_flags = sbsec->flags & SE_MNTMASK; | |
661 | ||
662 | /* check if the old mount command had the same options */ | |
663 | if (sbsec->flags & SE_SBINITIALIZED) | |
664 | if (!(sbsec->flags & flag) || | |
665 | (old_sid != new_sid)) | |
666 | return 1; | |
667 | ||
668 | /* check if we were passed the same options twice, | |
669 | * aka someone passed context=a,context=b | |
670 | */ | |
671 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
672 | if (mnt_flags & flag) | |
673 | return 1; | |
674 | return 0; | |
675 | } | |
676 | ||
677 | /* | |
678 | * Allow filesystems with binary mount data to explicitly set mount point | |
679 | * labeling information. | |
680 | */ | |
681 | static int selinux_set_mnt_opts(struct super_block *sb, | |
682 | struct security_mnt_opts *opts, | |
683 | unsigned long kern_flags, | |
684 | unsigned long *set_kern_flags) | |
685 | { | |
686 | const struct cred *cred = current_cred(); | |
687 | int rc = 0, i; | |
688 | struct superblock_security_struct *sbsec = sb->s_security; | |
689 | const char *name = sb->s_type->name; | |
690 | struct dentry *root = sbsec->sb->s_root; | |
691 | struct inode_security_struct *root_isec; | |
692 | u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0; | |
693 | u32 defcontext_sid = 0; | |
694 | char **mount_options = opts->mnt_opts; | |
695 | int *flags = opts->mnt_opts_flags; | |
696 | int num_opts = opts->num_mnt_opts; | |
697 | ||
698 | mutex_lock(&sbsec->lock); | |
699 | ||
700 | if (!ss_initialized) { | |
701 | if (!num_opts) { | |
702 | /* Defer initialization until selinux_complete_init, | |
703 | after the initial policy is loaded and the security | |
704 | server is ready to handle calls. */ | |
705 | goto out; | |
706 | } | |
707 | rc = -EINVAL; | |
708 | printk(KERN_WARNING "SELinux: Unable to set superblock options " | |
709 | "before the security server is initialized\n"); | |
710 | goto out; | |
711 | } | |
712 | if (kern_flags && !set_kern_flags) { | |
713 | /* Specifying internal flags without providing a place to | |
714 | * place the results is not allowed */ | |
715 | rc = -EINVAL; | |
716 | goto out; | |
717 | } | |
718 | ||
719 | /* | |
720 | * Binary mount data FS will come through this function twice. Once | |
721 | * from an explicit call and once from the generic calls from the vfs. | |
722 | * Since the generic VFS calls will not contain any security mount data | |
723 | * we need to skip the double mount verification. | |
724 | * | |
725 | * This does open a hole in which we will not notice if the first | |
726 | * mount using this sb set explict options and a second mount using | |
727 | * this sb does not set any security options. (The first options | |
728 | * will be used for both mounts) | |
729 | */ | |
730 | if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
731 | && (num_opts == 0)) | |
732 | goto out; | |
733 | ||
734 | root_isec = backing_inode_security_novalidate(root); | |
735 | ||
736 | /* | |
737 | * parse the mount options, check if they are valid sids. | |
738 | * also check if someone is trying to mount the same sb more | |
739 | * than once with different security options. | |
740 | */ | |
741 | for (i = 0; i < num_opts; i++) { | |
742 | u32 sid; | |
743 | ||
744 | if (flags[i] == SBLABEL_MNT) | |
745 | continue; | |
746 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); | |
747 | if (rc) { | |
748 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" | |
749 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
750 | mount_options[i], sb->s_id, name, rc); | |
751 | goto out; | |
752 | } | |
753 | switch (flags[i]) { | |
754 | case FSCONTEXT_MNT: | |
755 | fscontext_sid = sid; | |
756 | ||
757 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, | |
758 | fscontext_sid)) | |
759 | goto out_double_mount; | |
760 | ||
761 | sbsec->flags |= FSCONTEXT_MNT; | |
762 | break; | |
763 | case CONTEXT_MNT: | |
764 | context_sid = sid; | |
765 | ||
766 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, | |
767 | context_sid)) | |
768 | goto out_double_mount; | |
769 | ||
770 | sbsec->flags |= CONTEXT_MNT; | |
771 | break; | |
772 | case ROOTCONTEXT_MNT: | |
773 | rootcontext_sid = sid; | |
774 | ||
775 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, | |
776 | rootcontext_sid)) | |
777 | goto out_double_mount; | |
778 | ||
779 | sbsec->flags |= ROOTCONTEXT_MNT; | |
780 | ||
781 | break; | |
782 | case DEFCONTEXT_MNT: | |
783 | defcontext_sid = sid; | |
784 | ||
785 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, | |
786 | defcontext_sid)) | |
787 | goto out_double_mount; | |
788 | ||
789 | sbsec->flags |= DEFCONTEXT_MNT; | |
790 | ||
791 | break; | |
792 | default: | |
793 | rc = -EINVAL; | |
794 | goto out; | |
795 | } | |
796 | } | |
797 | ||
798 | if (sbsec->flags & SE_SBINITIALIZED) { | |
799 | /* previously mounted with options, but not on this attempt? */ | |
800 | if ((sbsec->flags & SE_MNTMASK) && !num_opts) | |
801 | goto out_double_mount; | |
802 | rc = 0; | |
803 | goto out; | |
804 | } | |
805 | ||
806 | if (strcmp(sb->s_type->name, "proc") == 0) | |
807 | sbsec->flags |= SE_SBPROC | SE_SBGENFS; | |
808 | ||
809 | if (!strcmp(sb->s_type->name, "debugfs") || | |
810 | !strcmp(sb->s_type->name, "sysfs") || | |
811 | !strcmp(sb->s_type->name, "pstore")) | |
812 | sbsec->flags |= SE_SBGENFS; | |
813 | ||
814 | if (!sbsec->behavior) { | |
815 | /* | |
816 | * Determine the labeling behavior to use for this | |
817 | * filesystem type. | |
818 | */ | |
819 | rc = security_fs_use(sb); | |
820 | if (rc) { | |
821 | printk(KERN_WARNING | |
822 | "%s: security_fs_use(%s) returned %d\n", | |
823 | __func__, sb->s_type->name, rc); | |
824 | goto out; | |
825 | } | |
826 | } | |
827 | ||
828 | /* | |
829 | * If this is a user namespace mount and the filesystem type is not | |
830 | * explicitly whitelisted, then no contexts are allowed on the command | |
831 | * line and security labels must be ignored. | |
832 | */ | |
833 | if (sb->s_user_ns != &init_user_ns && | |
834 | strcmp(sb->s_type->name, "tmpfs") && | |
835 | strcmp(sb->s_type->name, "ramfs") && | |
836 | strcmp(sb->s_type->name, "devpts")) { | |
837 | if (context_sid || fscontext_sid || rootcontext_sid || | |
838 | defcontext_sid) { | |
839 | rc = -EACCES; | |
840 | goto out; | |
841 | } | |
842 | if (sbsec->behavior == SECURITY_FS_USE_XATTR) { | |
843 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
844 | rc = security_transition_sid(current_sid(), current_sid(), | |
845 | SECCLASS_FILE, NULL, | |
846 | &sbsec->mntpoint_sid); | |
847 | if (rc) | |
848 | goto out; | |
849 | } | |
850 | goto out_set_opts; | |
851 | } | |
852 | ||
853 | /* sets the context of the superblock for the fs being mounted. */ | |
854 | if (fscontext_sid) { | |
855 | rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred); | |
856 | if (rc) | |
857 | goto out; | |
858 | ||
859 | sbsec->sid = fscontext_sid; | |
860 | } | |
861 | ||
862 | /* | |
863 | * Switch to using mount point labeling behavior. | |
864 | * sets the label used on all file below the mountpoint, and will set | |
865 | * the superblock context if not already set. | |
866 | */ | |
867 | if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) { | |
868 | sbsec->behavior = SECURITY_FS_USE_NATIVE; | |
869 | *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS; | |
870 | } | |
871 | ||
872 | if (context_sid) { | |
873 | if (!fscontext_sid) { | |
874 | rc = may_context_mount_sb_relabel(context_sid, sbsec, | |
875 | cred); | |
876 | if (rc) | |
877 | goto out; | |
878 | sbsec->sid = context_sid; | |
879 | } else { | |
880 | rc = may_context_mount_inode_relabel(context_sid, sbsec, | |
881 | cred); | |
882 | if (rc) | |
883 | goto out; | |
884 | } | |
885 | if (!rootcontext_sid) | |
886 | rootcontext_sid = context_sid; | |
887 | ||
888 | sbsec->mntpoint_sid = context_sid; | |
889 | sbsec->behavior = SECURITY_FS_USE_MNTPOINT; | |
890 | } | |
891 | ||
892 | if (rootcontext_sid) { | |
893 | rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, | |
894 | cred); | |
895 | if (rc) | |
896 | goto out; | |
897 | ||
898 | root_isec->sid = rootcontext_sid; | |
899 | root_isec->initialized = LABEL_INITIALIZED; | |
900 | } | |
901 | ||
902 | if (defcontext_sid) { | |
903 | if (sbsec->behavior != SECURITY_FS_USE_XATTR && | |
904 | sbsec->behavior != SECURITY_FS_USE_NATIVE) { | |
905 | rc = -EINVAL; | |
906 | printk(KERN_WARNING "SELinux: defcontext option is " | |
907 | "invalid for this filesystem type\n"); | |
908 | goto out; | |
909 | } | |
910 | ||
911 | if (defcontext_sid != sbsec->def_sid) { | |
912 | rc = may_context_mount_inode_relabel(defcontext_sid, | |
913 | sbsec, cred); | |
914 | if (rc) | |
915 | goto out; | |
916 | } | |
917 | ||
918 | sbsec->def_sid = defcontext_sid; | |
919 | } | |
920 | ||
921 | out_set_opts: | |
922 | rc = sb_finish_set_opts(sb); | |
923 | out: | |
924 | mutex_unlock(&sbsec->lock); | |
925 | return rc; | |
926 | out_double_mount: | |
927 | rc = -EINVAL; | |
928 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different " | |
929 | "security settings for (dev %s, type %s)\n", sb->s_id, name); | |
930 | goto out; | |
931 | } | |
932 | ||
933 | static int selinux_cmp_sb_context(const struct super_block *oldsb, | |
934 | const struct super_block *newsb) | |
935 | { | |
936 | struct superblock_security_struct *old = oldsb->s_security; | |
937 | struct superblock_security_struct *new = newsb->s_security; | |
938 | char oldflags = old->flags & SE_MNTMASK; | |
939 | char newflags = new->flags & SE_MNTMASK; | |
940 | ||
941 | if (oldflags != newflags) | |
942 | goto mismatch; | |
943 | if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid) | |
944 | goto mismatch; | |
945 | if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid) | |
946 | goto mismatch; | |
947 | if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid) | |
948 | goto mismatch; | |
949 | if (oldflags & ROOTCONTEXT_MNT) { | |
950 | struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root); | |
951 | struct inode_security_struct *newroot = backing_inode_security(newsb->s_root); | |
952 | if (oldroot->sid != newroot->sid) | |
953 | goto mismatch; | |
954 | } | |
955 | return 0; | |
956 | mismatch: | |
957 | printk(KERN_WARNING "SELinux: mount invalid. Same superblock, " | |
958 | "different security settings for (dev %s, " | |
959 | "type %s)\n", newsb->s_id, newsb->s_type->name); | |
960 | return -EBUSY; | |
961 | } | |
962 | ||
963 | static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb, | |
964 | struct super_block *newsb) | |
965 | { | |
966 | const struct superblock_security_struct *oldsbsec = oldsb->s_security; | |
967 | struct superblock_security_struct *newsbsec = newsb->s_security; | |
968 | ||
969 | int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT); | |
970 | int set_context = (oldsbsec->flags & CONTEXT_MNT); | |
971 | int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT); | |
972 | ||
973 | /* | |
974 | * if the parent was able to be mounted it clearly had no special lsm | |
975 | * mount options. thus we can safely deal with this superblock later | |
976 | */ | |
977 | if (!ss_initialized) | |
978 | return 0; | |
979 | ||
980 | /* how can we clone if the old one wasn't set up?? */ | |
981 | BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED)); | |
982 | ||
983 | /* if fs is reusing a sb, make sure that the contexts match */ | |
984 | if (newsbsec->flags & SE_SBINITIALIZED) | |
985 | return selinux_cmp_sb_context(oldsb, newsb); | |
986 | ||
987 | mutex_lock(&newsbsec->lock); | |
988 | ||
989 | newsbsec->flags = oldsbsec->flags; | |
990 | ||
991 | newsbsec->sid = oldsbsec->sid; | |
992 | newsbsec->def_sid = oldsbsec->def_sid; | |
993 | newsbsec->behavior = oldsbsec->behavior; | |
994 | ||
995 | if (set_context) { | |
996 | u32 sid = oldsbsec->mntpoint_sid; | |
997 | ||
998 | if (!set_fscontext) | |
999 | newsbsec->sid = sid; | |
1000 | if (!set_rootcontext) { | |
1001 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1002 | newisec->sid = sid; | |
1003 | } | |
1004 | newsbsec->mntpoint_sid = sid; | |
1005 | } | |
1006 | if (set_rootcontext) { | |
1007 | const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root); | |
1008 | struct inode_security_struct *newisec = backing_inode_security(newsb->s_root); | |
1009 | ||
1010 | newisec->sid = oldisec->sid; | |
1011 | } | |
1012 | ||
1013 | sb_finish_set_opts(newsb); | |
1014 | mutex_unlock(&newsbsec->lock); | |
1015 | return 0; | |
1016 | } | |
1017 | ||
1018 | static int selinux_parse_opts_str(char *options, | |
1019 | struct security_mnt_opts *opts) | |
1020 | { | |
1021 | char *p; | |
1022 | char *context = NULL, *defcontext = NULL; | |
1023 | char *fscontext = NULL, *rootcontext = NULL; | |
1024 | int rc, num_mnt_opts = 0; | |
1025 | ||
1026 | opts->num_mnt_opts = 0; | |
1027 | ||
1028 | /* Standard string-based options. */ | |
1029 | while ((p = strsep(&options, "|")) != NULL) { | |
1030 | int token; | |
1031 | substring_t args[MAX_OPT_ARGS]; | |
1032 | ||
1033 | if (!*p) | |
1034 | continue; | |
1035 | ||
1036 | token = match_token(p, tokens, args); | |
1037 | ||
1038 | switch (token) { | |
1039 | case Opt_context: | |
1040 | if (context || defcontext) { | |
1041 | rc = -EINVAL; | |
1042 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1043 | goto out_err; | |
1044 | } | |
1045 | context = match_strdup(&args[0]); | |
1046 | if (!context) { | |
1047 | rc = -ENOMEM; | |
1048 | goto out_err; | |
1049 | } | |
1050 | break; | |
1051 | ||
1052 | case Opt_fscontext: | |
1053 | if (fscontext) { | |
1054 | rc = -EINVAL; | |
1055 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1056 | goto out_err; | |
1057 | } | |
1058 | fscontext = match_strdup(&args[0]); | |
1059 | if (!fscontext) { | |
1060 | rc = -ENOMEM; | |
1061 | goto out_err; | |
1062 | } | |
1063 | break; | |
1064 | ||
1065 | case Opt_rootcontext: | |
1066 | if (rootcontext) { | |
1067 | rc = -EINVAL; | |
1068 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1069 | goto out_err; | |
1070 | } | |
1071 | rootcontext = match_strdup(&args[0]); | |
1072 | if (!rootcontext) { | |
1073 | rc = -ENOMEM; | |
1074 | goto out_err; | |
1075 | } | |
1076 | break; | |
1077 | ||
1078 | case Opt_defcontext: | |
1079 | if (context || defcontext) { | |
1080 | rc = -EINVAL; | |
1081 | printk(KERN_WARNING SEL_MOUNT_FAIL_MSG); | |
1082 | goto out_err; | |
1083 | } | |
1084 | defcontext = match_strdup(&args[0]); | |
1085 | if (!defcontext) { | |
1086 | rc = -ENOMEM; | |
1087 | goto out_err; | |
1088 | } | |
1089 | break; | |
1090 | case Opt_labelsupport: | |
1091 | break; | |
1092 | default: | |
1093 | rc = -EINVAL; | |
1094 | printk(KERN_WARNING "SELinux: unknown mount option\n"); | |
1095 | goto out_err; | |
1096 | ||
1097 | } | |
1098 | } | |
1099 | ||
1100 | rc = -ENOMEM; | |
1101 | opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL); | |
1102 | if (!opts->mnt_opts) | |
1103 | goto out_err; | |
1104 | ||
1105 | opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), | |
1106 | GFP_KERNEL); | |
1107 | if (!opts->mnt_opts_flags) { | |
1108 | kfree(opts->mnt_opts); | |
1109 | goto out_err; | |
1110 | } | |
1111 | ||
1112 | if (fscontext) { | |
1113 | opts->mnt_opts[num_mnt_opts] = fscontext; | |
1114 | opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT; | |
1115 | } | |
1116 | if (context) { | |
1117 | opts->mnt_opts[num_mnt_opts] = context; | |
1118 | opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT; | |
1119 | } | |
1120 | if (rootcontext) { | |
1121 | opts->mnt_opts[num_mnt_opts] = rootcontext; | |
1122 | opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT; | |
1123 | } | |
1124 | if (defcontext) { | |
1125 | opts->mnt_opts[num_mnt_opts] = defcontext; | |
1126 | opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT; | |
1127 | } | |
1128 | ||
1129 | opts->num_mnt_opts = num_mnt_opts; | |
1130 | return 0; | |
1131 | ||
1132 | out_err: | |
1133 | kfree(context); | |
1134 | kfree(defcontext); | |
1135 | kfree(fscontext); | |
1136 | kfree(rootcontext); | |
1137 | return rc; | |
1138 | } | |
1139 | /* | |
1140 | * string mount options parsing and call set the sbsec | |
1141 | */ | |
1142 | static int superblock_doinit(struct super_block *sb, void *data) | |
1143 | { | |
1144 | int rc = 0; | |
1145 | char *options = data; | |
1146 | struct security_mnt_opts opts; | |
1147 | ||
1148 | security_init_mnt_opts(&opts); | |
1149 | ||
1150 | if (!data) | |
1151 | goto out; | |
1152 | ||
1153 | BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA); | |
1154 | ||
1155 | rc = selinux_parse_opts_str(options, &opts); | |
1156 | if (rc) | |
1157 | goto out_err; | |
1158 | ||
1159 | out: | |
1160 | rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); | |
1161 | ||
1162 | out_err: | |
1163 | security_free_mnt_opts(&opts); | |
1164 | return rc; | |
1165 | } | |
1166 | ||
1167 | static void selinux_write_opts(struct seq_file *m, | |
1168 | struct security_mnt_opts *opts) | |
1169 | { | |
1170 | int i; | |
1171 | char *prefix; | |
1172 | ||
1173 | for (i = 0; i < opts->num_mnt_opts; i++) { | |
1174 | char *has_comma; | |
1175 | ||
1176 | if (opts->mnt_opts[i]) | |
1177 | has_comma = strchr(opts->mnt_opts[i], ','); | |
1178 | else | |
1179 | has_comma = NULL; | |
1180 | ||
1181 | switch (opts->mnt_opts_flags[i]) { | |
1182 | case CONTEXT_MNT: | |
1183 | prefix = CONTEXT_STR; | |
1184 | break; | |
1185 | case FSCONTEXT_MNT: | |
1186 | prefix = FSCONTEXT_STR; | |
1187 | break; | |
1188 | case ROOTCONTEXT_MNT: | |
1189 | prefix = ROOTCONTEXT_STR; | |
1190 | break; | |
1191 | case DEFCONTEXT_MNT: | |
1192 | prefix = DEFCONTEXT_STR; | |
1193 | break; | |
1194 | case SBLABEL_MNT: | |
1195 | seq_putc(m, ','); | |
1196 | seq_puts(m, LABELSUPP_STR); | |
1197 | continue; | |
1198 | default: | |
1199 | BUG(); | |
1200 | return; | |
1201 | }; | |
1202 | /* we need a comma before each option */ | |
1203 | seq_putc(m, ','); | |
1204 | seq_puts(m, prefix); | |
1205 | if (has_comma) | |
1206 | seq_putc(m, '\"'); | |
1207 | seq_escape(m, opts->mnt_opts[i], "\"\n\\"); | |
1208 | if (has_comma) | |
1209 | seq_putc(m, '\"'); | |
1210 | } | |
1211 | } | |
1212 | ||
1213 | static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb) | |
1214 | { | |
1215 | struct security_mnt_opts opts; | |
1216 | int rc; | |
1217 | ||
1218 | rc = selinux_get_mnt_opts(sb, &opts); | |
1219 | if (rc) { | |
1220 | /* before policy load we may get EINVAL, don't show anything */ | |
1221 | if (rc == -EINVAL) | |
1222 | rc = 0; | |
1223 | return rc; | |
1224 | } | |
1225 | ||
1226 | selinux_write_opts(m, &opts); | |
1227 | ||
1228 | security_free_mnt_opts(&opts); | |
1229 | ||
1230 | return rc; | |
1231 | } | |
1232 | ||
1233 | static inline u16 inode_mode_to_security_class(umode_t mode) | |
1234 | { | |
1235 | switch (mode & S_IFMT) { | |
1236 | case S_IFSOCK: | |
1237 | return SECCLASS_SOCK_FILE; | |
1238 | case S_IFLNK: | |
1239 | return SECCLASS_LNK_FILE; | |
1240 | case S_IFREG: | |
1241 | return SECCLASS_FILE; | |
1242 | case S_IFBLK: | |
1243 | return SECCLASS_BLK_FILE; | |
1244 | case S_IFDIR: | |
1245 | return SECCLASS_DIR; | |
1246 | case S_IFCHR: | |
1247 | return SECCLASS_CHR_FILE; | |
1248 | case S_IFIFO: | |
1249 | return SECCLASS_FIFO_FILE; | |
1250 | ||
1251 | } | |
1252 | ||
1253 | return SECCLASS_FILE; | |
1254 | } | |
1255 | ||
1256 | static inline int default_protocol_stream(int protocol) | |
1257 | { | |
1258 | return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); | |
1259 | } | |
1260 | ||
1261 | static inline int default_protocol_dgram(int protocol) | |
1262 | { | |
1263 | return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP); | |
1264 | } | |
1265 | ||
1266 | static inline u16 socket_type_to_security_class(int family, int type, int protocol) | |
1267 | { | |
1268 | int extsockclass = selinux_policycap_extsockclass; | |
1269 | ||
1270 | switch (family) { | |
1271 | case PF_UNIX: | |
1272 | switch (type) { | |
1273 | case SOCK_STREAM: | |
1274 | case SOCK_SEQPACKET: | |
1275 | return SECCLASS_UNIX_STREAM_SOCKET; | |
1276 | case SOCK_DGRAM: | |
1277 | return SECCLASS_UNIX_DGRAM_SOCKET; | |
1278 | } | |
1279 | break; | |
1280 | case PF_INET: | |
1281 | case PF_INET6: | |
1282 | switch (type) { | |
1283 | case SOCK_STREAM: | |
1284 | case SOCK_SEQPACKET: | |
1285 | if (default_protocol_stream(protocol)) | |
1286 | return SECCLASS_TCP_SOCKET; | |
1287 | else if (extsockclass && protocol == IPPROTO_SCTP) | |
1288 | return SECCLASS_SCTP_SOCKET; | |
1289 | else | |
1290 | return SECCLASS_RAWIP_SOCKET; | |
1291 | case SOCK_DGRAM: | |
1292 | if (default_protocol_dgram(protocol)) | |
1293 | return SECCLASS_UDP_SOCKET; | |
1294 | else if (extsockclass && (protocol == IPPROTO_ICMP || | |
1295 | protocol == IPPROTO_ICMPV6)) | |
1296 | return SECCLASS_ICMP_SOCKET; | |
1297 | else | |
1298 | return SECCLASS_RAWIP_SOCKET; | |
1299 | case SOCK_DCCP: | |
1300 | return SECCLASS_DCCP_SOCKET; | |
1301 | default: | |
1302 | return SECCLASS_RAWIP_SOCKET; | |
1303 | } | |
1304 | break; | |
1305 | case PF_NETLINK: | |
1306 | switch (protocol) { | |
1307 | case NETLINK_ROUTE: | |
1308 | return SECCLASS_NETLINK_ROUTE_SOCKET; | |
1309 | case NETLINK_SOCK_DIAG: | |
1310 | return SECCLASS_NETLINK_TCPDIAG_SOCKET; | |
1311 | case NETLINK_NFLOG: | |
1312 | return SECCLASS_NETLINK_NFLOG_SOCKET; | |
1313 | case NETLINK_XFRM: | |
1314 | return SECCLASS_NETLINK_XFRM_SOCKET; | |
1315 | case NETLINK_SELINUX: | |
1316 | return SECCLASS_NETLINK_SELINUX_SOCKET; | |
1317 | case NETLINK_ISCSI: | |
1318 | return SECCLASS_NETLINK_ISCSI_SOCKET; | |
1319 | case NETLINK_AUDIT: | |
1320 | return SECCLASS_NETLINK_AUDIT_SOCKET; | |
1321 | case NETLINK_FIB_LOOKUP: | |
1322 | return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET; | |
1323 | case NETLINK_CONNECTOR: | |
1324 | return SECCLASS_NETLINK_CONNECTOR_SOCKET; | |
1325 | case NETLINK_NETFILTER: | |
1326 | return SECCLASS_NETLINK_NETFILTER_SOCKET; | |
1327 | case NETLINK_DNRTMSG: | |
1328 | return SECCLASS_NETLINK_DNRT_SOCKET; | |
1329 | case NETLINK_KOBJECT_UEVENT: | |
1330 | return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET; | |
1331 | case NETLINK_GENERIC: | |
1332 | return SECCLASS_NETLINK_GENERIC_SOCKET; | |
1333 | case NETLINK_SCSITRANSPORT: | |
1334 | return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET; | |
1335 | case NETLINK_RDMA: | |
1336 | return SECCLASS_NETLINK_RDMA_SOCKET; | |
1337 | case NETLINK_CRYPTO: | |
1338 | return SECCLASS_NETLINK_CRYPTO_SOCKET; | |
1339 | default: | |
1340 | return SECCLASS_NETLINK_SOCKET; | |
1341 | } | |
1342 | case PF_PACKET: | |
1343 | return SECCLASS_PACKET_SOCKET; | |
1344 | case PF_KEY: | |
1345 | return SECCLASS_KEY_SOCKET; | |
1346 | case PF_APPLETALK: | |
1347 | return SECCLASS_APPLETALK_SOCKET; | |
1348 | } | |
1349 | ||
1350 | if (extsockclass) { | |
1351 | switch (family) { | |
1352 | case PF_AX25: | |
1353 | return SECCLASS_AX25_SOCKET; | |
1354 | case PF_IPX: | |
1355 | return SECCLASS_IPX_SOCKET; | |
1356 | case PF_NETROM: | |
1357 | return SECCLASS_NETROM_SOCKET; | |
1358 | case PF_ATMPVC: | |
1359 | return SECCLASS_ATMPVC_SOCKET; | |
1360 | case PF_X25: | |
1361 | return SECCLASS_X25_SOCKET; | |
1362 | case PF_ROSE: | |
1363 | return SECCLASS_ROSE_SOCKET; | |
1364 | case PF_DECnet: | |
1365 | return SECCLASS_DECNET_SOCKET; | |
1366 | case PF_ATMSVC: | |
1367 | return SECCLASS_ATMSVC_SOCKET; | |
1368 | case PF_RDS: | |
1369 | return SECCLASS_RDS_SOCKET; | |
1370 | case PF_IRDA: | |
1371 | return SECCLASS_IRDA_SOCKET; | |
1372 | case PF_PPPOX: | |
1373 | return SECCLASS_PPPOX_SOCKET; | |
1374 | case PF_LLC: | |
1375 | return SECCLASS_LLC_SOCKET; | |
1376 | case PF_CAN: | |
1377 | return SECCLASS_CAN_SOCKET; | |
1378 | case PF_TIPC: | |
1379 | return SECCLASS_TIPC_SOCKET; | |
1380 | case PF_BLUETOOTH: | |
1381 | return SECCLASS_BLUETOOTH_SOCKET; | |
1382 | case PF_IUCV: | |
1383 | return SECCLASS_IUCV_SOCKET; | |
1384 | case PF_RXRPC: | |
1385 | return SECCLASS_RXRPC_SOCKET; | |
1386 | case PF_ISDN: | |
1387 | return SECCLASS_ISDN_SOCKET; | |
1388 | case PF_PHONET: | |
1389 | return SECCLASS_PHONET_SOCKET; | |
1390 | case PF_IEEE802154: | |
1391 | return SECCLASS_IEEE802154_SOCKET; | |
1392 | case PF_CAIF: | |
1393 | return SECCLASS_CAIF_SOCKET; | |
1394 | case PF_ALG: | |
1395 | return SECCLASS_ALG_SOCKET; | |
1396 | case PF_NFC: | |
1397 | return SECCLASS_NFC_SOCKET; | |
1398 | case PF_VSOCK: | |
1399 | return SECCLASS_VSOCK_SOCKET; | |
1400 | case PF_KCM: | |
1401 | return SECCLASS_KCM_SOCKET; | |
1402 | case PF_QIPCRTR: | |
1403 | return SECCLASS_QIPCRTR_SOCKET; | |
1404 | case PF_SMC: | |
1405 | return SECCLASS_SMC_SOCKET; | |
1406 | #if PF_MAX > 44 | |
1407 | #error New address family defined, please update this function. | |
1408 | #endif | |
1409 | } | |
1410 | } | |
1411 | ||
1412 | return SECCLASS_SOCKET; | |
1413 | } | |
1414 | ||
1415 | static int selinux_genfs_get_sid(struct dentry *dentry, | |
1416 | u16 tclass, | |
1417 | u16 flags, | |
1418 | u32 *sid) | |
1419 | { | |
1420 | int rc; | |
1421 | struct super_block *sb = dentry->d_sb; | |
1422 | char *buffer, *path; | |
1423 | ||
1424 | buffer = (char *)__get_free_page(GFP_KERNEL); | |
1425 | if (!buffer) | |
1426 | return -ENOMEM; | |
1427 | ||
1428 | path = dentry_path_raw(dentry, buffer, PAGE_SIZE); | |
1429 | if (IS_ERR(path)) | |
1430 | rc = PTR_ERR(path); | |
1431 | else { | |
1432 | if (flags & SE_SBPROC) { | |
1433 | /* each process gets a /proc/PID/ entry. Strip off the | |
1434 | * PID part to get a valid selinux labeling. | |
1435 | * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */ | |
1436 | while (path[1] >= '0' && path[1] <= '9') { | |
1437 | path[1] = '/'; | |
1438 | path++; | |
1439 | } | |
1440 | } | |
1441 | rc = security_genfs_sid(sb->s_type->name, path, tclass, sid); | |
1442 | } | |
1443 | free_page((unsigned long)buffer); | |
1444 | return rc; | |
1445 | } | |
1446 | ||
1447 | /* The inode's security attributes must be initialized before first use. */ | |
1448 | static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry) | |
1449 | { | |
1450 | struct superblock_security_struct *sbsec = NULL; | |
1451 | struct inode_security_struct *isec = inode->i_security; | |
1452 | u32 task_sid, sid = 0; | |
1453 | u16 sclass; | |
1454 | struct dentry *dentry; | |
1455 | #define INITCONTEXTLEN 255 | |
1456 | char *context = NULL; | |
1457 | unsigned len = 0; | |
1458 | int rc = 0; | |
1459 | ||
1460 | if (isec->initialized == LABEL_INITIALIZED) | |
1461 | return 0; | |
1462 | ||
1463 | spin_lock(&isec->lock); | |
1464 | if (isec->initialized == LABEL_INITIALIZED) | |
1465 | goto out_unlock; | |
1466 | ||
1467 | if (isec->sclass == SECCLASS_FILE) | |
1468 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
1469 | ||
1470 | sbsec = inode->i_sb->s_security; | |
1471 | if (!(sbsec->flags & SE_SBINITIALIZED)) { | |
1472 | /* Defer initialization until selinux_complete_init, | |
1473 | after the initial policy is loaded and the security | |
1474 | server is ready to handle calls. */ | |
1475 | spin_lock(&sbsec->isec_lock); | |
1476 | if (list_empty(&isec->list)) | |
1477 | list_add(&isec->list, &sbsec->isec_head); | |
1478 | spin_unlock(&sbsec->isec_lock); | |
1479 | goto out_unlock; | |
1480 | } | |
1481 | ||
1482 | sclass = isec->sclass; | |
1483 | task_sid = isec->task_sid; | |
1484 | sid = isec->sid; | |
1485 | isec->initialized = LABEL_PENDING; | |
1486 | spin_unlock(&isec->lock); | |
1487 | ||
1488 | switch (sbsec->behavior) { | |
1489 | case SECURITY_FS_USE_NATIVE: | |
1490 | break; | |
1491 | case SECURITY_FS_USE_XATTR: | |
1492 | if (!(inode->i_opflags & IOP_XATTR)) { | |
1493 | sid = sbsec->def_sid; | |
1494 | break; | |
1495 | } | |
1496 | /* Need a dentry, since the xattr API requires one. | |
1497 | Life would be simpler if we could just pass the inode. */ | |
1498 | if (opt_dentry) { | |
1499 | /* Called from d_instantiate or d_splice_alias. */ | |
1500 | dentry = dget(opt_dentry); | |
1501 | } else { | |
1502 | /* Called from selinux_complete_init, try to find a dentry. */ | |
1503 | dentry = d_find_alias(inode); | |
1504 | } | |
1505 | if (!dentry) { | |
1506 | /* | |
1507 | * this is can be hit on boot when a file is accessed | |
1508 | * before the policy is loaded. When we load policy we | |
1509 | * may find inodes that have no dentry on the | |
1510 | * sbsec->isec_head list. No reason to complain as these | |
1511 | * will get fixed up the next time we go through | |
1512 | * inode_doinit with a dentry, before these inodes could | |
1513 | * be used again by userspace. | |
1514 | */ | |
1515 | goto out; | |
1516 | } | |
1517 | ||
1518 | len = INITCONTEXTLEN; | |
1519 | context = kmalloc(len+1, GFP_NOFS); | |
1520 | if (!context) { | |
1521 | rc = -ENOMEM; | |
1522 | dput(dentry); | |
1523 | goto out; | |
1524 | } | |
1525 | context[len] = '\0'; | |
1526 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1527 | if (rc == -ERANGE) { | |
1528 | kfree(context); | |
1529 | ||
1530 | /* Need a larger buffer. Query for the right size. */ | |
1531 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0); | |
1532 | if (rc < 0) { | |
1533 | dput(dentry); | |
1534 | goto out; | |
1535 | } | |
1536 | len = rc; | |
1537 | context = kmalloc(len+1, GFP_NOFS); | |
1538 | if (!context) { | |
1539 | rc = -ENOMEM; | |
1540 | dput(dentry); | |
1541 | goto out; | |
1542 | } | |
1543 | context[len] = '\0'; | |
1544 | rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len); | |
1545 | } | |
1546 | dput(dentry); | |
1547 | if (rc < 0) { | |
1548 | if (rc != -ENODATA) { | |
1549 | printk(KERN_WARNING "SELinux: %s: getxattr returned " | |
1550 | "%d for dev=%s ino=%ld\n", __func__, | |
1551 | -rc, inode->i_sb->s_id, inode->i_ino); | |
1552 | kfree(context); | |
1553 | goto out; | |
1554 | } | |
1555 | /* Map ENODATA to the default file SID */ | |
1556 | sid = sbsec->def_sid; | |
1557 | rc = 0; | |
1558 | } else { | |
1559 | rc = security_context_to_sid_default(context, rc, &sid, | |
1560 | sbsec->def_sid, | |
1561 | GFP_NOFS); | |
1562 | if (rc) { | |
1563 | char *dev = inode->i_sb->s_id; | |
1564 | unsigned long ino = inode->i_ino; | |
1565 | ||
1566 | if (rc == -EINVAL) { | |
1567 | if (printk_ratelimit()) | |
1568 | printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid " | |
1569 | "context=%s. This indicates you may need to relabel the inode or the " | |
1570 | "filesystem in question.\n", ino, dev, context); | |
1571 | } else { | |
1572 | printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) " | |
1573 | "returned %d for dev=%s ino=%ld\n", | |
1574 | __func__, context, -rc, dev, ino); | |
1575 | } | |
1576 | kfree(context); | |
1577 | /* Leave with the unlabeled SID */ | |
1578 | rc = 0; | |
1579 | break; | |
1580 | } | |
1581 | } | |
1582 | kfree(context); | |
1583 | break; | |
1584 | case SECURITY_FS_USE_TASK: | |
1585 | sid = task_sid; | |
1586 | break; | |
1587 | case SECURITY_FS_USE_TRANS: | |
1588 | /* Default to the fs SID. */ | |
1589 | sid = sbsec->sid; | |
1590 | ||
1591 | /* Try to obtain a transition SID. */ | |
1592 | rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid); | |
1593 | if (rc) | |
1594 | goto out; | |
1595 | break; | |
1596 | case SECURITY_FS_USE_MNTPOINT: | |
1597 | sid = sbsec->mntpoint_sid; | |
1598 | break; | |
1599 | default: | |
1600 | /* Default to the fs superblock SID. */ | |
1601 | sid = sbsec->sid; | |
1602 | ||
1603 | if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) { | |
1604 | /* We must have a dentry to determine the label on | |
1605 | * procfs inodes */ | |
1606 | if (opt_dentry) | |
1607 | /* Called from d_instantiate or | |
1608 | * d_splice_alias. */ | |
1609 | dentry = dget(opt_dentry); | |
1610 | else | |
1611 | /* Called from selinux_complete_init, try to | |
1612 | * find a dentry. */ | |
1613 | dentry = d_find_alias(inode); | |
1614 | /* | |
1615 | * This can be hit on boot when a file is accessed | |
1616 | * before the policy is loaded. When we load policy we | |
1617 | * may find inodes that have no dentry on the | |
1618 | * sbsec->isec_head list. No reason to complain as | |
1619 | * these will get fixed up the next time we go through | |
1620 | * inode_doinit() with a dentry, before these inodes | |
1621 | * could be used again by userspace. | |
1622 | */ | |
1623 | if (!dentry) | |
1624 | goto out; | |
1625 | rc = selinux_genfs_get_sid(dentry, sclass, | |
1626 | sbsec->flags, &sid); | |
1627 | dput(dentry); | |
1628 | if (rc) | |
1629 | goto out; | |
1630 | } | |
1631 | break; | |
1632 | } | |
1633 | ||
1634 | out: | |
1635 | spin_lock(&isec->lock); | |
1636 | if (isec->initialized == LABEL_PENDING) { | |
1637 | if (!sid || rc) { | |
1638 | isec->initialized = LABEL_INVALID; | |
1639 | goto out_unlock; | |
1640 | } | |
1641 | ||
1642 | isec->initialized = LABEL_INITIALIZED; | |
1643 | isec->sid = sid; | |
1644 | } | |
1645 | ||
1646 | out_unlock: | |
1647 | spin_unlock(&isec->lock); | |
1648 | return rc; | |
1649 | } | |
1650 | ||
1651 | /* Convert a Linux signal to an access vector. */ | |
1652 | static inline u32 signal_to_av(int sig) | |
1653 | { | |
1654 | u32 perm = 0; | |
1655 | ||
1656 | switch (sig) { | |
1657 | case SIGCHLD: | |
1658 | /* Commonly granted from child to parent. */ | |
1659 | perm = PROCESS__SIGCHLD; | |
1660 | break; | |
1661 | case SIGKILL: | |
1662 | /* Cannot be caught or ignored */ | |
1663 | perm = PROCESS__SIGKILL; | |
1664 | break; | |
1665 | case SIGSTOP: | |
1666 | /* Cannot be caught or ignored */ | |
1667 | perm = PROCESS__SIGSTOP; | |
1668 | break; | |
1669 | default: | |
1670 | /* All other signals. */ | |
1671 | perm = PROCESS__SIGNAL; | |
1672 | break; | |
1673 | } | |
1674 | ||
1675 | return perm; | |
1676 | } | |
1677 | ||
1678 | #if CAP_LAST_CAP > 63 | |
1679 | #error Fix SELinux to handle capabilities > 63. | |
1680 | #endif | |
1681 | ||
1682 | /* Check whether a task is allowed to use a capability. */ | |
1683 | static int cred_has_capability(const struct cred *cred, | |
1684 | int cap, int audit, bool initns) | |
1685 | { | |
1686 | struct common_audit_data ad; | |
1687 | struct av_decision avd; | |
1688 | u16 sclass; | |
1689 | u32 sid = cred_sid(cred); | |
1690 | u32 av = CAP_TO_MASK(cap); | |
1691 | int rc; | |
1692 | ||
1693 | ad.type = LSM_AUDIT_DATA_CAP; | |
1694 | ad.u.cap = cap; | |
1695 | ||
1696 | switch (CAP_TO_INDEX(cap)) { | |
1697 | case 0: | |
1698 | sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS; | |
1699 | break; | |
1700 | case 1: | |
1701 | sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS; | |
1702 | break; | |
1703 | default: | |
1704 | printk(KERN_ERR | |
1705 | "SELinux: out of range capability %d\n", cap); | |
1706 | BUG(); | |
1707 | return -EINVAL; | |
1708 | } | |
1709 | ||
1710 | rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd); | |
1711 | if (audit == SECURITY_CAP_AUDIT) { | |
1712 | int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0); | |
1713 | if (rc2) | |
1714 | return rc2; | |
1715 | } | |
1716 | return rc; | |
1717 | } | |
1718 | ||
1719 | /* Check whether a task has a particular permission to an inode. | |
1720 | The 'adp' parameter is optional and allows other audit | |
1721 | data to be passed (e.g. the dentry). */ | |
1722 | static int inode_has_perm(const struct cred *cred, | |
1723 | struct inode *inode, | |
1724 | u32 perms, | |
1725 | struct common_audit_data *adp) | |
1726 | { | |
1727 | struct inode_security_struct *isec; | |
1728 | u32 sid; | |
1729 | ||
1730 | validate_creds(cred); | |
1731 | ||
1732 | if (unlikely(IS_PRIVATE(inode))) | |
1733 | return 0; | |
1734 | ||
1735 | sid = cred_sid(cred); | |
1736 | isec = inode->i_security; | |
1737 | ||
1738 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp); | |
1739 | } | |
1740 | ||
1741 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1742 | the dentry to help the auditing code to more easily generate the | |
1743 | pathname if needed. */ | |
1744 | static inline int dentry_has_perm(const struct cred *cred, | |
1745 | struct dentry *dentry, | |
1746 | u32 av) | |
1747 | { | |
1748 | struct inode *inode = d_backing_inode(dentry); | |
1749 | struct common_audit_data ad; | |
1750 | ||
1751 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
1752 | ad.u.dentry = dentry; | |
1753 | __inode_security_revalidate(inode, dentry, true); | |
1754 | return inode_has_perm(cred, inode, av, &ad); | |
1755 | } | |
1756 | ||
1757 | /* Same as inode_has_perm, but pass explicit audit data containing | |
1758 | the path to help the auditing code to more easily generate the | |
1759 | pathname if needed. */ | |
1760 | static inline int path_has_perm(const struct cred *cred, | |
1761 | const struct path *path, | |
1762 | u32 av) | |
1763 | { | |
1764 | struct inode *inode = d_backing_inode(path->dentry); | |
1765 | struct common_audit_data ad; | |
1766 | ||
1767 | ad.type = LSM_AUDIT_DATA_PATH; | |
1768 | ad.u.path = *path; | |
1769 | __inode_security_revalidate(inode, path->dentry, true); | |
1770 | return inode_has_perm(cred, inode, av, &ad); | |
1771 | } | |
1772 | ||
1773 | /* Same as path_has_perm, but uses the inode from the file struct. */ | |
1774 | static inline int file_path_has_perm(const struct cred *cred, | |
1775 | struct file *file, | |
1776 | u32 av) | |
1777 | { | |
1778 | struct common_audit_data ad; | |
1779 | ||
1780 | ad.type = LSM_AUDIT_DATA_FILE; | |
1781 | ad.u.file = file; | |
1782 | return inode_has_perm(cred, file_inode(file), av, &ad); | |
1783 | } | |
1784 | ||
1785 | /* Check whether a task can use an open file descriptor to | |
1786 | access an inode in a given way. Check access to the | |
1787 | descriptor itself, and then use dentry_has_perm to | |
1788 | check a particular permission to the file. | |
1789 | Access to the descriptor is implicitly granted if it | |
1790 | has the same SID as the process. If av is zero, then | |
1791 | access to the file is not checked, e.g. for cases | |
1792 | where only the descriptor is affected like seek. */ | |
1793 | static int file_has_perm(const struct cred *cred, | |
1794 | struct file *file, | |
1795 | u32 av) | |
1796 | { | |
1797 | struct file_security_struct *fsec = file->f_security; | |
1798 | struct inode *inode = file_inode(file); | |
1799 | struct common_audit_data ad; | |
1800 | u32 sid = cred_sid(cred); | |
1801 | int rc; | |
1802 | ||
1803 | ad.type = LSM_AUDIT_DATA_FILE; | |
1804 | ad.u.file = file; | |
1805 | ||
1806 | if (sid != fsec->sid) { | |
1807 | rc = avc_has_perm(sid, fsec->sid, | |
1808 | SECCLASS_FD, | |
1809 | FD__USE, | |
1810 | &ad); | |
1811 | if (rc) | |
1812 | goto out; | |
1813 | } | |
1814 | ||
1815 | /* av is zero if only checking access to the descriptor. */ | |
1816 | rc = 0; | |
1817 | if (av) | |
1818 | rc = inode_has_perm(cred, inode, av, &ad); | |
1819 | ||
1820 | out: | |
1821 | return rc; | |
1822 | } | |
1823 | ||
1824 | /* | |
1825 | * Determine the label for an inode that might be unioned. | |
1826 | */ | |
1827 | static int | |
1828 | selinux_determine_inode_label(const struct task_security_struct *tsec, | |
1829 | struct inode *dir, | |
1830 | const struct qstr *name, u16 tclass, | |
1831 | u32 *_new_isid) | |
1832 | { | |
1833 | const struct superblock_security_struct *sbsec = dir->i_sb->s_security; | |
1834 | ||
1835 | if ((sbsec->flags & SE_SBINITIALIZED) && | |
1836 | (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) { | |
1837 | *_new_isid = sbsec->mntpoint_sid; | |
1838 | } else if ((sbsec->flags & SBLABEL_MNT) && | |
1839 | tsec->create_sid) { | |
1840 | *_new_isid = tsec->create_sid; | |
1841 | } else { | |
1842 | const struct inode_security_struct *dsec = inode_security(dir); | |
1843 | return security_transition_sid(tsec->sid, dsec->sid, tclass, | |
1844 | name, _new_isid); | |
1845 | } | |
1846 | ||
1847 | return 0; | |
1848 | } | |
1849 | ||
1850 | /* Check whether a task can create a file. */ | |
1851 | static int may_create(struct inode *dir, | |
1852 | struct dentry *dentry, | |
1853 | u16 tclass) | |
1854 | { | |
1855 | const struct task_security_struct *tsec = current_security(); | |
1856 | struct inode_security_struct *dsec; | |
1857 | struct superblock_security_struct *sbsec; | |
1858 | u32 sid, newsid; | |
1859 | struct common_audit_data ad; | |
1860 | int rc; | |
1861 | ||
1862 | dsec = inode_security(dir); | |
1863 | sbsec = dir->i_sb->s_security; | |
1864 | ||
1865 | sid = tsec->sid; | |
1866 | ||
1867 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
1868 | ad.u.dentry = dentry; | |
1869 | ||
1870 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, | |
1871 | DIR__ADD_NAME | DIR__SEARCH, | |
1872 | &ad); | |
1873 | if (rc) | |
1874 | return rc; | |
1875 | ||
1876 | rc = selinux_determine_inode_label(current_security(), dir, | |
1877 | &dentry->d_name, tclass, &newsid); | |
1878 | if (rc) | |
1879 | return rc; | |
1880 | ||
1881 | rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad); | |
1882 | if (rc) | |
1883 | return rc; | |
1884 | ||
1885 | return avc_has_perm(newsid, sbsec->sid, | |
1886 | SECCLASS_FILESYSTEM, | |
1887 | FILESYSTEM__ASSOCIATE, &ad); | |
1888 | } | |
1889 | ||
1890 | #define MAY_LINK 0 | |
1891 | #define MAY_UNLINK 1 | |
1892 | #define MAY_RMDIR 2 | |
1893 | ||
1894 | /* Check whether a task can link, unlink, or rmdir a file/directory. */ | |
1895 | static int may_link(struct inode *dir, | |
1896 | struct dentry *dentry, | |
1897 | int kind) | |
1898 | ||
1899 | { | |
1900 | struct inode_security_struct *dsec, *isec; | |
1901 | struct common_audit_data ad; | |
1902 | u32 sid = current_sid(); | |
1903 | u32 av; | |
1904 | int rc; | |
1905 | ||
1906 | dsec = inode_security(dir); | |
1907 | isec = backing_inode_security(dentry); | |
1908 | ||
1909 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
1910 | ad.u.dentry = dentry; | |
1911 | ||
1912 | av = DIR__SEARCH; | |
1913 | av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME); | |
1914 | rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad); | |
1915 | if (rc) | |
1916 | return rc; | |
1917 | ||
1918 | switch (kind) { | |
1919 | case MAY_LINK: | |
1920 | av = FILE__LINK; | |
1921 | break; | |
1922 | case MAY_UNLINK: | |
1923 | av = FILE__UNLINK; | |
1924 | break; | |
1925 | case MAY_RMDIR: | |
1926 | av = DIR__RMDIR; | |
1927 | break; | |
1928 | default: | |
1929 | printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n", | |
1930 | __func__, kind); | |
1931 | return 0; | |
1932 | } | |
1933 | ||
1934 | rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad); | |
1935 | return rc; | |
1936 | } | |
1937 | ||
1938 | static inline int may_rename(struct inode *old_dir, | |
1939 | struct dentry *old_dentry, | |
1940 | struct inode *new_dir, | |
1941 | struct dentry *new_dentry) | |
1942 | { | |
1943 | struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec; | |
1944 | struct common_audit_data ad; | |
1945 | u32 sid = current_sid(); | |
1946 | u32 av; | |
1947 | int old_is_dir, new_is_dir; | |
1948 | int rc; | |
1949 | ||
1950 | old_dsec = inode_security(old_dir); | |
1951 | old_isec = backing_inode_security(old_dentry); | |
1952 | old_is_dir = d_is_dir(old_dentry); | |
1953 | new_dsec = inode_security(new_dir); | |
1954 | ||
1955 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
1956 | ||
1957 | ad.u.dentry = old_dentry; | |
1958 | rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR, | |
1959 | DIR__REMOVE_NAME | DIR__SEARCH, &ad); | |
1960 | if (rc) | |
1961 | return rc; | |
1962 | rc = avc_has_perm(sid, old_isec->sid, | |
1963 | old_isec->sclass, FILE__RENAME, &ad); | |
1964 | if (rc) | |
1965 | return rc; | |
1966 | if (old_is_dir && new_dir != old_dir) { | |
1967 | rc = avc_has_perm(sid, old_isec->sid, | |
1968 | old_isec->sclass, DIR__REPARENT, &ad); | |
1969 | if (rc) | |
1970 | return rc; | |
1971 | } | |
1972 | ||
1973 | ad.u.dentry = new_dentry; | |
1974 | av = DIR__ADD_NAME | DIR__SEARCH; | |
1975 | if (d_is_positive(new_dentry)) | |
1976 | av |= DIR__REMOVE_NAME; | |
1977 | rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad); | |
1978 | if (rc) | |
1979 | return rc; | |
1980 | if (d_is_positive(new_dentry)) { | |
1981 | new_isec = backing_inode_security(new_dentry); | |
1982 | new_is_dir = d_is_dir(new_dentry); | |
1983 | rc = avc_has_perm(sid, new_isec->sid, | |
1984 | new_isec->sclass, | |
1985 | (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad); | |
1986 | if (rc) | |
1987 | return rc; | |
1988 | } | |
1989 | ||
1990 | return 0; | |
1991 | } | |
1992 | ||
1993 | /* Check whether a task can perform a filesystem operation. */ | |
1994 | static int superblock_has_perm(const struct cred *cred, | |
1995 | struct super_block *sb, | |
1996 | u32 perms, | |
1997 | struct common_audit_data *ad) | |
1998 | { | |
1999 | struct superblock_security_struct *sbsec; | |
2000 | u32 sid = cred_sid(cred); | |
2001 | ||
2002 | sbsec = sb->s_security; | |
2003 | return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad); | |
2004 | } | |
2005 | ||
2006 | /* Convert a Linux mode and permission mask to an access vector. */ | |
2007 | static inline u32 file_mask_to_av(int mode, int mask) | |
2008 | { | |
2009 | u32 av = 0; | |
2010 | ||
2011 | if (!S_ISDIR(mode)) { | |
2012 | if (mask & MAY_EXEC) | |
2013 | av |= FILE__EXECUTE; | |
2014 | if (mask & MAY_READ) | |
2015 | av |= FILE__READ; | |
2016 | ||
2017 | if (mask & MAY_APPEND) | |
2018 | av |= FILE__APPEND; | |
2019 | else if (mask & MAY_WRITE) | |
2020 | av |= FILE__WRITE; | |
2021 | ||
2022 | } else { | |
2023 | if (mask & MAY_EXEC) | |
2024 | av |= DIR__SEARCH; | |
2025 | if (mask & MAY_WRITE) | |
2026 | av |= DIR__WRITE; | |
2027 | if (mask & MAY_READ) | |
2028 | av |= DIR__READ; | |
2029 | } | |
2030 | ||
2031 | return av; | |
2032 | } | |
2033 | ||
2034 | /* Convert a Linux file to an access vector. */ | |
2035 | static inline u32 file_to_av(struct file *file) | |
2036 | { | |
2037 | u32 av = 0; | |
2038 | ||
2039 | if (file->f_mode & FMODE_READ) | |
2040 | av |= FILE__READ; | |
2041 | if (file->f_mode & FMODE_WRITE) { | |
2042 | if (file->f_flags & O_APPEND) | |
2043 | av |= FILE__APPEND; | |
2044 | else | |
2045 | av |= FILE__WRITE; | |
2046 | } | |
2047 | if (!av) { | |
2048 | /* | |
2049 | * Special file opened with flags 3 for ioctl-only use. | |
2050 | */ | |
2051 | av = FILE__IOCTL; | |
2052 | } | |
2053 | ||
2054 | return av; | |
2055 | } | |
2056 | ||
2057 | /* | |
2058 | * Convert a file to an access vector and include the correct open | |
2059 | * open permission. | |
2060 | */ | |
2061 | static inline u32 open_file_to_av(struct file *file) | |
2062 | { | |
2063 | u32 av = file_to_av(file); | |
2064 | ||
2065 | if (selinux_policycap_openperm) | |
2066 | av |= FILE__OPEN; | |
2067 | ||
2068 | return av; | |
2069 | } | |
2070 | ||
2071 | /* Hook functions begin here. */ | |
2072 | ||
2073 | static int selinux_binder_set_context_mgr(struct task_struct *mgr) | |
2074 | { | |
2075 | u32 mysid = current_sid(); | |
2076 | u32 mgrsid = task_sid(mgr); | |
2077 | ||
2078 | return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER, | |
2079 | BINDER__SET_CONTEXT_MGR, NULL); | |
2080 | } | |
2081 | ||
2082 | static int selinux_binder_transaction(struct task_struct *from, | |
2083 | struct task_struct *to) | |
2084 | { | |
2085 | u32 mysid = current_sid(); | |
2086 | u32 fromsid = task_sid(from); | |
2087 | u32 tosid = task_sid(to); | |
2088 | int rc; | |
2089 | ||
2090 | if (mysid != fromsid) { | |
2091 | rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER, | |
2092 | BINDER__IMPERSONATE, NULL); | |
2093 | if (rc) | |
2094 | return rc; | |
2095 | } | |
2096 | ||
2097 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL, | |
2098 | NULL); | |
2099 | } | |
2100 | ||
2101 | static int selinux_binder_transfer_binder(struct task_struct *from, | |
2102 | struct task_struct *to) | |
2103 | { | |
2104 | u32 fromsid = task_sid(from); | |
2105 | u32 tosid = task_sid(to); | |
2106 | ||
2107 | return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER, | |
2108 | NULL); | |
2109 | } | |
2110 | ||
2111 | static int selinux_binder_transfer_file(struct task_struct *from, | |
2112 | struct task_struct *to, | |
2113 | struct file *file) | |
2114 | { | |
2115 | u32 sid = task_sid(to); | |
2116 | struct file_security_struct *fsec = file->f_security; | |
2117 | struct dentry *dentry = file->f_path.dentry; | |
2118 | struct inode_security_struct *isec; | |
2119 | struct common_audit_data ad; | |
2120 | int rc; | |
2121 | ||
2122 | ad.type = LSM_AUDIT_DATA_PATH; | |
2123 | ad.u.path = file->f_path; | |
2124 | ||
2125 | if (sid != fsec->sid) { | |
2126 | rc = avc_has_perm(sid, fsec->sid, | |
2127 | SECCLASS_FD, | |
2128 | FD__USE, | |
2129 | &ad); | |
2130 | if (rc) | |
2131 | return rc; | |
2132 | } | |
2133 | ||
2134 | if (unlikely(IS_PRIVATE(d_backing_inode(dentry)))) | |
2135 | return 0; | |
2136 | ||
2137 | isec = backing_inode_security(dentry); | |
2138 | return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file), | |
2139 | &ad); | |
2140 | } | |
2141 | ||
2142 | static int selinux_ptrace_access_check(struct task_struct *child, | |
2143 | unsigned int mode) | |
2144 | { | |
2145 | u32 sid = current_sid(); | |
2146 | u32 csid = task_sid(child); | |
2147 | ||
2148 | if (mode & PTRACE_MODE_READ) | |
2149 | return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL); | |
2150 | ||
2151 | return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL); | |
2152 | } | |
2153 | ||
2154 | static int selinux_ptrace_traceme(struct task_struct *parent) | |
2155 | { | |
2156 | return avc_has_perm(task_sid(parent), current_sid(), SECCLASS_PROCESS, | |
2157 | PROCESS__PTRACE, NULL); | |
2158 | } | |
2159 | ||
2160 | static int selinux_capget(struct task_struct *target, kernel_cap_t *effective, | |
2161 | kernel_cap_t *inheritable, kernel_cap_t *permitted) | |
2162 | { | |
2163 | return avc_has_perm(current_sid(), task_sid(target), SECCLASS_PROCESS, | |
2164 | PROCESS__GETCAP, NULL); | |
2165 | } | |
2166 | ||
2167 | static int selinux_capset(struct cred *new, const struct cred *old, | |
2168 | const kernel_cap_t *effective, | |
2169 | const kernel_cap_t *inheritable, | |
2170 | const kernel_cap_t *permitted) | |
2171 | { | |
2172 | return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS, | |
2173 | PROCESS__SETCAP, NULL); | |
2174 | } | |
2175 | ||
2176 | /* | |
2177 | * (This comment used to live with the selinux_task_setuid hook, | |
2178 | * which was removed). | |
2179 | * | |
2180 | * Since setuid only affects the current process, and since the SELinux | |
2181 | * controls are not based on the Linux identity attributes, SELinux does not | |
2182 | * need to control this operation. However, SELinux does control the use of | |
2183 | * the CAP_SETUID and CAP_SETGID capabilities using the capable hook. | |
2184 | */ | |
2185 | ||
2186 | static int selinux_capable(const struct cred *cred, struct user_namespace *ns, | |
2187 | int cap, int audit) | |
2188 | { | |
2189 | return cred_has_capability(cred, cap, audit, ns == &init_user_ns); | |
2190 | } | |
2191 | ||
2192 | static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) | |
2193 | { | |
2194 | const struct cred *cred = current_cred(); | |
2195 | int rc = 0; | |
2196 | ||
2197 | if (!sb) | |
2198 | return 0; | |
2199 | ||
2200 | switch (cmds) { | |
2201 | case Q_SYNC: | |
2202 | case Q_QUOTAON: | |
2203 | case Q_QUOTAOFF: | |
2204 | case Q_SETINFO: | |
2205 | case Q_SETQUOTA: | |
2206 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL); | |
2207 | break; | |
2208 | case Q_GETFMT: | |
2209 | case Q_GETINFO: | |
2210 | case Q_GETQUOTA: | |
2211 | rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL); | |
2212 | break; | |
2213 | default: | |
2214 | rc = 0; /* let the kernel handle invalid cmds */ | |
2215 | break; | |
2216 | } | |
2217 | return rc; | |
2218 | } | |
2219 | ||
2220 | static int selinux_quota_on(struct dentry *dentry) | |
2221 | { | |
2222 | const struct cred *cred = current_cred(); | |
2223 | ||
2224 | return dentry_has_perm(cred, dentry, FILE__QUOTAON); | |
2225 | } | |
2226 | ||
2227 | static int selinux_syslog(int type) | |
2228 | { | |
2229 | switch (type) { | |
2230 | case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */ | |
2231 | case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */ | |
2232 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
2233 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL); | |
2234 | case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */ | |
2235 | case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */ | |
2236 | /* Set level of messages printed to console */ | |
2237 | case SYSLOG_ACTION_CONSOLE_LEVEL: | |
2238 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
2239 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE, | |
2240 | NULL); | |
2241 | } | |
2242 | /* All other syslog types */ | |
2243 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
2244 | SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL); | |
2245 | } | |
2246 | ||
2247 | /* | |
2248 | * Check that a process has enough memory to allocate a new virtual | |
2249 | * mapping. 0 means there is enough memory for the allocation to | |
2250 | * succeed and -ENOMEM implies there is not. | |
2251 | * | |
2252 | * Do not audit the selinux permission check, as this is applied to all | |
2253 | * processes that allocate mappings. | |
2254 | */ | |
2255 | static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) | |
2256 | { | |
2257 | int rc, cap_sys_admin = 0; | |
2258 | ||
2259 | rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, | |
2260 | SECURITY_CAP_NOAUDIT, true); | |
2261 | if (rc == 0) | |
2262 | cap_sys_admin = 1; | |
2263 | ||
2264 | return cap_sys_admin; | |
2265 | } | |
2266 | ||
2267 | /* binprm security operations */ | |
2268 | ||
2269 | static u32 ptrace_parent_sid(void) | |
2270 | { | |
2271 | u32 sid = 0; | |
2272 | struct task_struct *tracer; | |
2273 | ||
2274 | rcu_read_lock(); | |
2275 | tracer = ptrace_parent(current); | |
2276 | if (tracer) | |
2277 | sid = task_sid(tracer); | |
2278 | rcu_read_unlock(); | |
2279 | ||
2280 | return sid; | |
2281 | } | |
2282 | ||
2283 | static int check_nnp_nosuid(const struct linux_binprm *bprm, | |
2284 | const struct task_security_struct *old_tsec, | |
2285 | const struct task_security_struct *new_tsec) | |
2286 | { | |
2287 | int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS); | |
2288 | int nosuid = !mnt_may_suid(bprm->file->f_path.mnt); | |
2289 | int rc; | |
2290 | ||
2291 | if (!nnp && !nosuid) | |
2292 | return 0; /* neither NNP nor nosuid */ | |
2293 | ||
2294 | if (new_tsec->sid == old_tsec->sid) | |
2295 | return 0; /* No change in credentials */ | |
2296 | ||
2297 | /* | |
2298 | * The only transitions we permit under NNP or nosuid | |
2299 | * are transitions to bounded SIDs, i.e. SIDs that are | |
2300 | * guaranteed to only be allowed a subset of the permissions | |
2301 | * of the current SID. | |
2302 | */ | |
2303 | rc = security_bounded_transition(old_tsec->sid, new_tsec->sid); | |
2304 | if (rc) { | |
2305 | /* | |
2306 | * On failure, preserve the errno values for NNP vs nosuid. | |
2307 | * NNP: Operation not permitted for caller. | |
2308 | * nosuid: Permission denied to file. | |
2309 | */ | |
2310 | if (nnp) | |
2311 | return -EPERM; | |
2312 | else | |
2313 | return -EACCES; | |
2314 | } | |
2315 | return 0; | |
2316 | } | |
2317 | ||
2318 | static int selinux_bprm_set_creds(struct linux_binprm *bprm) | |
2319 | { | |
2320 | const struct task_security_struct *old_tsec; | |
2321 | struct task_security_struct *new_tsec; | |
2322 | struct inode_security_struct *isec; | |
2323 | struct common_audit_data ad; | |
2324 | struct inode *inode = file_inode(bprm->file); | |
2325 | int rc; | |
2326 | ||
2327 | /* SELinux context only depends on initial program or script and not | |
2328 | * the script interpreter */ | |
2329 | if (bprm->cred_prepared) | |
2330 | return 0; | |
2331 | ||
2332 | old_tsec = current_security(); | |
2333 | new_tsec = bprm->cred->security; | |
2334 | isec = inode_security(inode); | |
2335 | ||
2336 | /* Default to the current task SID. */ | |
2337 | new_tsec->sid = old_tsec->sid; | |
2338 | new_tsec->osid = old_tsec->sid; | |
2339 | ||
2340 | /* Reset fs, key, and sock SIDs on execve. */ | |
2341 | new_tsec->create_sid = 0; | |
2342 | new_tsec->keycreate_sid = 0; | |
2343 | new_tsec->sockcreate_sid = 0; | |
2344 | ||
2345 | if (old_tsec->exec_sid) { | |
2346 | new_tsec->sid = old_tsec->exec_sid; | |
2347 | /* Reset exec SID on execve. */ | |
2348 | new_tsec->exec_sid = 0; | |
2349 | ||
2350 | /* Fail on NNP or nosuid if not an allowed transition. */ | |
2351 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2352 | if (rc) | |
2353 | return rc; | |
2354 | } else { | |
2355 | /* Check for a default transition on this program. */ | |
2356 | rc = security_transition_sid(old_tsec->sid, isec->sid, | |
2357 | SECCLASS_PROCESS, NULL, | |
2358 | &new_tsec->sid); | |
2359 | if (rc) | |
2360 | return rc; | |
2361 | ||
2362 | /* | |
2363 | * Fallback to old SID on NNP or nosuid if not an allowed | |
2364 | * transition. | |
2365 | */ | |
2366 | rc = check_nnp_nosuid(bprm, old_tsec, new_tsec); | |
2367 | if (rc) | |
2368 | new_tsec->sid = old_tsec->sid; | |
2369 | } | |
2370 | ||
2371 | ad.type = LSM_AUDIT_DATA_FILE; | |
2372 | ad.u.file = bprm->file; | |
2373 | ||
2374 | if (new_tsec->sid == old_tsec->sid) { | |
2375 | rc = avc_has_perm(old_tsec->sid, isec->sid, | |
2376 | SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad); | |
2377 | if (rc) | |
2378 | return rc; | |
2379 | } else { | |
2380 | /* Check permissions for the transition. */ | |
2381 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2382 | SECCLASS_PROCESS, PROCESS__TRANSITION, &ad); | |
2383 | if (rc) | |
2384 | return rc; | |
2385 | ||
2386 | rc = avc_has_perm(new_tsec->sid, isec->sid, | |
2387 | SECCLASS_FILE, FILE__ENTRYPOINT, &ad); | |
2388 | if (rc) | |
2389 | return rc; | |
2390 | ||
2391 | /* Check for shared state */ | |
2392 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { | |
2393 | rc = avc_has_perm(old_tsec->sid, new_tsec->sid, | |
2394 | SECCLASS_PROCESS, PROCESS__SHARE, | |
2395 | NULL); | |
2396 | if (rc) | |
2397 | return -EPERM; | |
2398 | } | |
2399 | ||
2400 | /* Make sure that anyone attempting to ptrace over a task that | |
2401 | * changes its SID has the appropriate permit */ | |
2402 | if (bprm->unsafe & LSM_UNSAFE_PTRACE) { | |
2403 | u32 ptsid = ptrace_parent_sid(); | |
2404 | if (ptsid != 0) { | |
2405 | rc = avc_has_perm(ptsid, new_tsec->sid, | |
2406 | SECCLASS_PROCESS, | |
2407 | PROCESS__PTRACE, NULL); | |
2408 | if (rc) | |
2409 | return -EPERM; | |
2410 | } | |
2411 | } | |
2412 | ||
2413 | /* Clear any possibly unsafe personality bits on exec: */ | |
2414 | bprm->per_clear |= PER_CLEAR_ON_SETID; | |
2415 | } | |
2416 | ||
2417 | return 0; | |
2418 | } | |
2419 | ||
2420 | static int selinux_bprm_secureexec(struct linux_binprm *bprm) | |
2421 | { | |
2422 | const struct task_security_struct *tsec = current_security(); | |
2423 | u32 sid, osid; | |
2424 | int atsecure = 0; | |
2425 | ||
2426 | sid = tsec->sid; | |
2427 | osid = tsec->osid; | |
2428 | ||
2429 | if (osid != sid) { | |
2430 | /* Enable secure mode for SIDs transitions unless | |
2431 | the noatsecure permission is granted between | |
2432 | the two SIDs, i.e. ahp returns 0. */ | |
2433 | atsecure = avc_has_perm(osid, sid, | |
2434 | SECCLASS_PROCESS, | |
2435 | PROCESS__NOATSECURE, NULL); | |
2436 | } | |
2437 | ||
2438 | return !!atsecure; | |
2439 | } | |
2440 | ||
2441 | static int match_file(const void *p, struct file *file, unsigned fd) | |
2442 | { | |
2443 | return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0; | |
2444 | } | |
2445 | ||
2446 | /* Derived from fs/exec.c:flush_old_files. */ | |
2447 | static inline void flush_unauthorized_files(const struct cred *cred, | |
2448 | struct files_struct *files) | |
2449 | { | |
2450 | struct file *file, *devnull = NULL; | |
2451 | struct tty_struct *tty; | |
2452 | int drop_tty = 0; | |
2453 | unsigned n; | |
2454 | ||
2455 | tty = get_current_tty(); | |
2456 | if (tty) { | |
2457 | spin_lock(&tty->files_lock); | |
2458 | if (!list_empty(&tty->tty_files)) { | |
2459 | struct tty_file_private *file_priv; | |
2460 | ||
2461 | /* Revalidate access to controlling tty. | |
2462 | Use file_path_has_perm on the tty path directly | |
2463 | rather than using file_has_perm, as this particular | |
2464 | open file may belong to another process and we are | |
2465 | only interested in the inode-based check here. */ | |
2466 | file_priv = list_first_entry(&tty->tty_files, | |
2467 | struct tty_file_private, list); | |
2468 | file = file_priv->file; | |
2469 | if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE)) | |
2470 | drop_tty = 1; | |
2471 | } | |
2472 | spin_unlock(&tty->files_lock); | |
2473 | tty_kref_put(tty); | |
2474 | } | |
2475 | /* Reset controlling tty. */ | |
2476 | if (drop_tty) | |
2477 | no_tty(); | |
2478 | ||
2479 | /* Revalidate access to inherited open files. */ | |
2480 | n = iterate_fd(files, 0, match_file, cred); | |
2481 | if (!n) /* none found? */ | |
2482 | return; | |
2483 | ||
2484 | devnull = dentry_open(&selinux_null, O_RDWR, cred); | |
2485 | if (IS_ERR(devnull)) | |
2486 | devnull = NULL; | |
2487 | /* replace all the matching ones with this */ | |
2488 | do { | |
2489 | replace_fd(n - 1, devnull, 0); | |
2490 | } while ((n = iterate_fd(files, n, match_file, cred)) != 0); | |
2491 | if (devnull) | |
2492 | fput(devnull); | |
2493 | } | |
2494 | ||
2495 | /* | |
2496 | * Prepare a process for imminent new credential changes due to exec | |
2497 | */ | |
2498 | static void selinux_bprm_committing_creds(struct linux_binprm *bprm) | |
2499 | { | |
2500 | struct task_security_struct *new_tsec; | |
2501 | struct rlimit *rlim, *initrlim; | |
2502 | int rc, i; | |
2503 | ||
2504 | new_tsec = bprm->cred->security; | |
2505 | if (new_tsec->sid == new_tsec->osid) | |
2506 | return; | |
2507 | ||
2508 | /* Close files for which the new task SID is not authorized. */ | |
2509 | flush_unauthorized_files(bprm->cred, current->files); | |
2510 | ||
2511 | /* Always clear parent death signal on SID transitions. */ | |
2512 | current->pdeath_signal = 0; | |
2513 | ||
2514 | /* Check whether the new SID can inherit resource limits from the old | |
2515 | * SID. If not, reset all soft limits to the lower of the current | |
2516 | * task's hard limit and the init task's soft limit. | |
2517 | * | |
2518 | * Note that the setting of hard limits (even to lower them) can be | |
2519 | * controlled by the setrlimit check. The inclusion of the init task's | |
2520 | * soft limit into the computation is to avoid resetting soft limits | |
2521 | * higher than the default soft limit for cases where the default is | |
2522 | * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK. | |
2523 | */ | |
2524 | rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS, | |
2525 | PROCESS__RLIMITINH, NULL); | |
2526 | if (rc) { | |
2527 | /* protect against do_prlimit() */ | |
2528 | task_lock(current); | |
2529 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
2530 | rlim = current->signal->rlim + i; | |
2531 | initrlim = init_task.signal->rlim + i; | |
2532 | rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); | |
2533 | } | |
2534 | task_unlock(current); | |
2535 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) | |
2536 | update_rlimit_cpu(current, rlimit(RLIMIT_CPU)); | |
2537 | } | |
2538 | } | |
2539 | ||
2540 | /* | |
2541 | * Clean up the process immediately after the installation of new credentials | |
2542 | * due to exec | |
2543 | */ | |
2544 | static void selinux_bprm_committed_creds(struct linux_binprm *bprm) | |
2545 | { | |
2546 | const struct task_security_struct *tsec = current_security(); | |
2547 | struct itimerval itimer; | |
2548 | u32 osid, sid; | |
2549 | int rc, i; | |
2550 | ||
2551 | osid = tsec->osid; | |
2552 | sid = tsec->sid; | |
2553 | ||
2554 | if (sid == osid) | |
2555 | return; | |
2556 | ||
2557 | /* Check whether the new SID can inherit signal state from the old SID. | |
2558 | * If not, clear itimers to avoid subsequent signal generation and | |
2559 | * flush and unblock signals. | |
2560 | * | |
2561 | * This must occur _after_ the task SID has been updated so that any | |
2562 | * kill done after the flush will be checked against the new SID. | |
2563 | */ | |
2564 | rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL); | |
2565 | if (rc) { | |
2566 | if (IS_ENABLED(CONFIG_POSIX_TIMERS)) { | |
2567 | memset(&itimer, 0, sizeof itimer); | |
2568 | for (i = 0; i < 3; i++) | |
2569 | do_setitimer(i, &itimer, NULL); | |
2570 | } | |
2571 | spin_lock_irq(¤t->sighand->siglock); | |
2572 | if (!fatal_signal_pending(current)) { | |
2573 | flush_sigqueue(¤t->pending); | |
2574 | flush_sigqueue(¤t->signal->shared_pending); | |
2575 | flush_signal_handlers(current, 1); | |
2576 | sigemptyset(¤t->blocked); | |
2577 | recalc_sigpending(); | |
2578 | } | |
2579 | spin_unlock_irq(¤t->sighand->siglock); | |
2580 | } | |
2581 | ||
2582 | /* Wake up the parent if it is waiting so that it can recheck | |
2583 | * wait permission to the new task SID. */ | |
2584 | read_lock(&tasklist_lock); | |
2585 | __wake_up_parent(current, current->real_parent); | |
2586 | read_unlock(&tasklist_lock); | |
2587 | } | |
2588 | ||
2589 | /* superblock security operations */ | |
2590 | ||
2591 | static int selinux_sb_alloc_security(struct super_block *sb) | |
2592 | { | |
2593 | return superblock_alloc_security(sb); | |
2594 | } | |
2595 | ||
2596 | static void selinux_sb_free_security(struct super_block *sb) | |
2597 | { | |
2598 | superblock_free_security(sb); | |
2599 | } | |
2600 | ||
2601 | static inline int match_prefix(char *prefix, int plen, char *option, int olen) | |
2602 | { | |
2603 | if (plen > olen) | |
2604 | return 0; | |
2605 | ||
2606 | return !memcmp(prefix, option, plen); | |
2607 | } | |
2608 | ||
2609 | static inline int selinux_option(char *option, int len) | |
2610 | { | |
2611 | return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) || | |
2612 | match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) || | |
2613 | match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) || | |
2614 | match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) || | |
2615 | match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len)); | |
2616 | } | |
2617 | ||
2618 | static inline void take_option(char **to, char *from, int *first, int len) | |
2619 | { | |
2620 | if (!*first) { | |
2621 | **to = ','; | |
2622 | *to += 1; | |
2623 | } else | |
2624 | *first = 0; | |
2625 | memcpy(*to, from, len); | |
2626 | *to += len; | |
2627 | } | |
2628 | ||
2629 | static inline void take_selinux_option(char **to, char *from, int *first, | |
2630 | int len) | |
2631 | { | |
2632 | int current_size = 0; | |
2633 | ||
2634 | if (!*first) { | |
2635 | **to = '|'; | |
2636 | *to += 1; | |
2637 | } else | |
2638 | *first = 0; | |
2639 | ||
2640 | while (current_size < len) { | |
2641 | if (*from != '"') { | |
2642 | **to = *from; | |
2643 | *to += 1; | |
2644 | } | |
2645 | from += 1; | |
2646 | current_size += 1; | |
2647 | } | |
2648 | } | |
2649 | ||
2650 | static int selinux_sb_copy_data(char *orig, char *copy) | |
2651 | { | |
2652 | int fnosec, fsec, rc = 0; | |
2653 | char *in_save, *in_curr, *in_end; | |
2654 | char *sec_curr, *nosec_save, *nosec; | |
2655 | int open_quote = 0; | |
2656 | ||
2657 | in_curr = orig; | |
2658 | sec_curr = copy; | |
2659 | ||
2660 | nosec = (char *)get_zeroed_page(GFP_KERNEL); | |
2661 | if (!nosec) { | |
2662 | rc = -ENOMEM; | |
2663 | goto out; | |
2664 | } | |
2665 | ||
2666 | nosec_save = nosec; | |
2667 | fnosec = fsec = 1; | |
2668 | in_save = in_end = orig; | |
2669 | ||
2670 | do { | |
2671 | if (*in_end == '"') | |
2672 | open_quote = !open_quote; | |
2673 | if ((*in_end == ',' && open_quote == 0) || | |
2674 | *in_end == '\0') { | |
2675 | int len = in_end - in_curr; | |
2676 | ||
2677 | if (selinux_option(in_curr, len)) | |
2678 | take_selinux_option(&sec_curr, in_curr, &fsec, len); | |
2679 | else | |
2680 | take_option(&nosec, in_curr, &fnosec, len); | |
2681 | ||
2682 | in_curr = in_end + 1; | |
2683 | } | |
2684 | } while (*in_end++); | |
2685 | ||
2686 | strcpy(in_save, nosec_save); | |
2687 | free_page((unsigned long)nosec_save); | |
2688 | out: | |
2689 | return rc; | |
2690 | } | |
2691 | ||
2692 | static int selinux_sb_remount(struct super_block *sb, void *data) | |
2693 | { | |
2694 | int rc, i, *flags; | |
2695 | struct security_mnt_opts opts; | |
2696 | char *secdata, **mount_options; | |
2697 | struct superblock_security_struct *sbsec = sb->s_security; | |
2698 | ||
2699 | if (!(sbsec->flags & SE_SBINITIALIZED)) | |
2700 | return 0; | |
2701 | ||
2702 | if (!data) | |
2703 | return 0; | |
2704 | ||
2705 | if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) | |
2706 | return 0; | |
2707 | ||
2708 | security_init_mnt_opts(&opts); | |
2709 | secdata = alloc_secdata(); | |
2710 | if (!secdata) | |
2711 | return -ENOMEM; | |
2712 | rc = selinux_sb_copy_data(data, secdata); | |
2713 | if (rc) | |
2714 | goto out_free_secdata; | |
2715 | ||
2716 | rc = selinux_parse_opts_str(secdata, &opts); | |
2717 | if (rc) | |
2718 | goto out_free_secdata; | |
2719 | ||
2720 | mount_options = opts.mnt_opts; | |
2721 | flags = opts.mnt_opts_flags; | |
2722 | ||
2723 | for (i = 0; i < opts.num_mnt_opts; i++) { | |
2724 | u32 sid; | |
2725 | ||
2726 | if (flags[i] == SBLABEL_MNT) | |
2727 | continue; | |
2728 | rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL); | |
2729 | if (rc) { | |
2730 | printk(KERN_WARNING "SELinux: security_context_str_to_sid" | |
2731 | "(%s) failed for (dev %s, type %s) errno=%d\n", | |
2732 | mount_options[i], sb->s_id, sb->s_type->name, rc); | |
2733 | goto out_free_opts; | |
2734 | } | |
2735 | rc = -EINVAL; | |
2736 | switch (flags[i]) { | |
2737 | case FSCONTEXT_MNT: | |
2738 | if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid)) | |
2739 | goto out_bad_option; | |
2740 | break; | |
2741 | case CONTEXT_MNT: | |
2742 | if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid)) | |
2743 | goto out_bad_option; | |
2744 | break; | |
2745 | case ROOTCONTEXT_MNT: { | |
2746 | struct inode_security_struct *root_isec; | |
2747 | root_isec = backing_inode_security(sb->s_root); | |
2748 | ||
2749 | if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid)) | |
2750 | goto out_bad_option; | |
2751 | break; | |
2752 | } | |
2753 | case DEFCONTEXT_MNT: | |
2754 | if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid)) | |
2755 | goto out_bad_option; | |
2756 | break; | |
2757 | default: | |
2758 | goto out_free_opts; | |
2759 | } | |
2760 | } | |
2761 | ||
2762 | rc = 0; | |
2763 | out_free_opts: | |
2764 | security_free_mnt_opts(&opts); | |
2765 | out_free_secdata: | |
2766 | free_secdata(secdata); | |
2767 | return rc; | |
2768 | out_bad_option: | |
2769 | printk(KERN_WARNING "SELinux: unable to change security options " | |
2770 | "during remount (dev %s, type=%s)\n", sb->s_id, | |
2771 | sb->s_type->name); | |
2772 | goto out_free_opts; | |
2773 | } | |
2774 | ||
2775 | static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data) | |
2776 | { | |
2777 | const struct cred *cred = current_cred(); | |
2778 | struct common_audit_data ad; | |
2779 | int rc; | |
2780 | ||
2781 | rc = superblock_doinit(sb, data); | |
2782 | if (rc) | |
2783 | return rc; | |
2784 | ||
2785 | /* Allow all mounts performed by the kernel */ | |
2786 | if (flags & MS_KERNMOUNT) | |
2787 | return 0; | |
2788 | ||
2789 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2790 | ad.u.dentry = sb->s_root; | |
2791 | return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad); | |
2792 | } | |
2793 | ||
2794 | static int selinux_sb_statfs(struct dentry *dentry) | |
2795 | { | |
2796 | const struct cred *cred = current_cred(); | |
2797 | struct common_audit_data ad; | |
2798 | ||
2799 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2800 | ad.u.dentry = dentry->d_sb->s_root; | |
2801 | return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad); | |
2802 | } | |
2803 | ||
2804 | static int selinux_mount(const char *dev_name, | |
2805 | const struct path *path, | |
2806 | const char *type, | |
2807 | unsigned long flags, | |
2808 | void *data) | |
2809 | { | |
2810 | const struct cred *cred = current_cred(); | |
2811 | ||
2812 | if (flags & MS_REMOUNT) | |
2813 | return superblock_has_perm(cred, path->dentry->d_sb, | |
2814 | FILESYSTEM__REMOUNT, NULL); | |
2815 | else | |
2816 | return path_has_perm(cred, path, FILE__MOUNTON); | |
2817 | } | |
2818 | ||
2819 | static int selinux_umount(struct vfsmount *mnt, int flags) | |
2820 | { | |
2821 | const struct cred *cred = current_cred(); | |
2822 | ||
2823 | return superblock_has_perm(cred, mnt->mnt_sb, | |
2824 | FILESYSTEM__UNMOUNT, NULL); | |
2825 | } | |
2826 | ||
2827 | /* inode security operations */ | |
2828 | ||
2829 | static int selinux_inode_alloc_security(struct inode *inode) | |
2830 | { | |
2831 | return inode_alloc_security(inode); | |
2832 | } | |
2833 | ||
2834 | static void selinux_inode_free_security(struct inode *inode) | |
2835 | { | |
2836 | inode_free_security(inode); | |
2837 | } | |
2838 | ||
2839 | static int selinux_dentry_init_security(struct dentry *dentry, int mode, | |
2840 | const struct qstr *name, void **ctx, | |
2841 | u32 *ctxlen) | |
2842 | { | |
2843 | u32 newsid; | |
2844 | int rc; | |
2845 | ||
2846 | rc = selinux_determine_inode_label(current_security(), | |
2847 | d_inode(dentry->d_parent), name, | |
2848 | inode_mode_to_security_class(mode), | |
2849 | &newsid); | |
2850 | if (rc) | |
2851 | return rc; | |
2852 | ||
2853 | return security_sid_to_context(newsid, (char **)ctx, ctxlen); | |
2854 | } | |
2855 | ||
2856 | static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, | |
2857 | struct qstr *name, | |
2858 | const struct cred *old, | |
2859 | struct cred *new) | |
2860 | { | |
2861 | u32 newsid; | |
2862 | int rc; | |
2863 | struct task_security_struct *tsec; | |
2864 | ||
2865 | rc = selinux_determine_inode_label(old->security, | |
2866 | d_inode(dentry->d_parent), name, | |
2867 | inode_mode_to_security_class(mode), | |
2868 | &newsid); | |
2869 | if (rc) | |
2870 | return rc; | |
2871 | ||
2872 | tsec = new->security; | |
2873 | tsec->create_sid = newsid; | |
2874 | return 0; | |
2875 | } | |
2876 | ||
2877 | static int selinux_inode_init_security(struct inode *inode, struct inode *dir, | |
2878 | const struct qstr *qstr, | |
2879 | const char **name, | |
2880 | void **value, size_t *len) | |
2881 | { | |
2882 | const struct task_security_struct *tsec = current_security(); | |
2883 | struct superblock_security_struct *sbsec; | |
2884 | u32 sid, newsid, clen; | |
2885 | int rc; | |
2886 | char *context; | |
2887 | ||
2888 | sbsec = dir->i_sb->s_security; | |
2889 | ||
2890 | sid = tsec->sid; | |
2891 | newsid = tsec->create_sid; | |
2892 | ||
2893 | rc = selinux_determine_inode_label(current_security(), | |
2894 | dir, qstr, | |
2895 | inode_mode_to_security_class(inode->i_mode), | |
2896 | &newsid); | |
2897 | if (rc) | |
2898 | return rc; | |
2899 | ||
2900 | /* Possibly defer initialization to selinux_complete_init. */ | |
2901 | if (sbsec->flags & SE_SBINITIALIZED) { | |
2902 | struct inode_security_struct *isec = inode->i_security; | |
2903 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
2904 | isec->sid = newsid; | |
2905 | isec->initialized = LABEL_INITIALIZED; | |
2906 | } | |
2907 | ||
2908 | if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT)) | |
2909 | return -EOPNOTSUPP; | |
2910 | ||
2911 | if (name) | |
2912 | *name = XATTR_SELINUX_SUFFIX; | |
2913 | ||
2914 | if (value && len) { | |
2915 | rc = security_sid_to_context_force(newsid, &context, &clen); | |
2916 | if (rc) | |
2917 | return rc; | |
2918 | *value = context; | |
2919 | *len = clen; | |
2920 | } | |
2921 | ||
2922 | return 0; | |
2923 | } | |
2924 | ||
2925 | static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) | |
2926 | { | |
2927 | return may_create(dir, dentry, SECCLASS_FILE); | |
2928 | } | |
2929 | ||
2930 | static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) | |
2931 | { | |
2932 | return may_link(dir, old_dentry, MAY_LINK); | |
2933 | } | |
2934 | ||
2935 | static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry) | |
2936 | { | |
2937 | return may_link(dir, dentry, MAY_UNLINK); | |
2938 | } | |
2939 | ||
2940 | static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name) | |
2941 | { | |
2942 | return may_create(dir, dentry, SECCLASS_LNK_FILE); | |
2943 | } | |
2944 | ||
2945 | static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask) | |
2946 | { | |
2947 | return may_create(dir, dentry, SECCLASS_DIR); | |
2948 | } | |
2949 | ||
2950 | static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry) | |
2951 | { | |
2952 | return may_link(dir, dentry, MAY_RMDIR); | |
2953 | } | |
2954 | ||
2955 | static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) | |
2956 | { | |
2957 | return may_create(dir, dentry, inode_mode_to_security_class(mode)); | |
2958 | } | |
2959 | ||
2960 | static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry, | |
2961 | struct inode *new_inode, struct dentry *new_dentry) | |
2962 | { | |
2963 | return may_rename(old_inode, old_dentry, new_inode, new_dentry); | |
2964 | } | |
2965 | ||
2966 | static int selinux_inode_readlink(struct dentry *dentry) | |
2967 | { | |
2968 | const struct cred *cred = current_cred(); | |
2969 | ||
2970 | return dentry_has_perm(cred, dentry, FILE__READ); | |
2971 | } | |
2972 | ||
2973 | static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, | |
2974 | bool rcu) | |
2975 | { | |
2976 | const struct cred *cred = current_cred(); | |
2977 | struct common_audit_data ad; | |
2978 | struct inode_security_struct *isec; | |
2979 | u32 sid; | |
2980 | ||
2981 | validate_creds(cred); | |
2982 | ||
2983 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
2984 | ad.u.dentry = dentry; | |
2985 | sid = cred_sid(cred); | |
2986 | isec = inode_security_rcu(inode, rcu); | |
2987 | if (IS_ERR(isec)) | |
2988 | return PTR_ERR(isec); | |
2989 | ||
2990 | return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad, | |
2991 | rcu ? MAY_NOT_BLOCK : 0); | |
2992 | } | |
2993 | ||
2994 | static noinline int audit_inode_permission(struct inode *inode, | |
2995 | u32 perms, u32 audited, u32 denied, | |
2996 | int result, | |
2997 | unsigned flags) | |
2998 | { | |
2999 | struct common_audit_data ad; | |
3000 | struct inode_security_struct *isec = inode->i_security; | |
3001 | int rc; | |
3002 | ||
3003 | ad.type = LSM_AUDIT_DATA_INODE; | |
3004 | ad.u.inode = inode; | |
3005 | ||
3006 | rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, | |
3007 | audited, denied, result, &ad, flags); | |
3008 | if (rc) | |
3009 | return rc; | |
3010 | return 0; | |
3011 | } | |
3012 | ||
3013 | static int selinux_inode_permission(struct inode *inode, int mask) | |
3014 | { | |
3015 | const struct cred *cred = current_cred(); | |
3016 | u32 perms; | |
3017 | bool from_access; | |
3018 | unsigned flags = mask & MAY_NOT_BLOCK; | |
3019 | struct inode_security_struct *isec; | |
3020 | u32 sid; | |
3021 | struct av_decision avd; | |
3022 | int rc, rc2; | |
3023 | u32 audited, denied; | |
3024 | ||
3025 | from_access = mask & MAY_ACCESS; | |
3026 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); | |
3027 | ||
3028 | /* No permission to check. Existence test. */ | |
3029 | if (!mask) | |
3030 | return 0; | |
3031 | ||
3032 | validate_creds(cred); | |
3033 | ||
3034 | if (unlikely(IS_PRIVATE(inode))) | |
3035 | return 0; | |
3036 | ||
3037 | perms = file_mask_to_av(inode->i_mode, mask); | |
3038 | ||
3039 | sid = cred_sid(cred); | |
3040 | isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK); | |
3041 | if (IS_ERR(isec)) | |
3042 | return PTR_ERR(isec); | |
3043 | ||
3044 | rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); | |
3045 | audited = avc_audit_required(perms, &avd, rc, | |
3046 | from_access ? FILE__AUDIT_ACCESS : 0, | |
3047 | &denied); | |
3048 | if (likely(!audited)) | |
3049 | return rc; | |
3050 | ||
3051 | rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); | |
3052 | if (rc2) | |
3053 | return rc2; | |
3054 | return rc; | |
3055 | } | |
3056 | ||
3057 | static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
3058 | { | |
3059 | const struct cred *cred = current_cred(); | |
3060 | unsigned int ia_valid = iattr->ia_valid; | |
3061 | __u32 av = FILE__WRITE; | |
3062 | ||
3063 | /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */ | |
3064 | if (ia_valid & ATTR_FORCE) { | |
3065 | ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE | | |
3066 | ATTR_FORCE); | |
3067 | if (!ia_valid) | |
3068 | return 0; | |
3069 | } | |
3070 | ||
3071 | if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | | |
3072 | ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET)) | |
3073 | return dentry_has_perm(cred, dentry, FILE__SETATTR); | |
3074 | ||
3075 | if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE) | |
3076 | && !(ia_valid & ATTR_FILE)) | |
3077 | av |= FILE__OPEN; | |
3078 | ||
3079 | return dentry_has_perm(cred, dentry, av); | |
3080 | } | |
3081 | ||
3082 | static int selinux_inode_getattr(const struct path *path) | |
3083 | { | |
3084 | return path_has_perm(current_cred(), path, FILE__GETATTR); | |
3085 | } | |
3086 | ||
3087 | static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) | |
3088 | { | |
3089 | const struct cred *cred = current_cred(); | |
3090 | ||
3091 | if (!strncmp(name, XATTR_SECURITY_PREFIX, | |
3092 | sizeof XATTR_SECURITY_PREFIX - 1)) { | |
3093 | if (!strcmp(name, XATTR_NAME_CAPS)) { | |
3094 | if (!capable(CAP_SETFCAP)) | |
3095 | return -EPERM; | |
3096 | } else if (!capable(CAP_SYS_ADMIN)) { | |
3097 | /* A different attribute in the security namespace. | |
3098 | Restrict to administrator. */ | |
3099 | return -EPERM; | |
3100 | } | |
3101 | } | |
3102 | ||
3103 | /* Not an attribute we recognize, so just check the | |
3104 | ordinary setattr permission. */ | |
3105 | return dentry_has_perm(cred, dentry, FILE__SETATTR); | |
3106 | } | |
3107 | ||
3108 | static int selinux_inode_setxattr(struct dentry *dentry, const char *name, | |
3109 | const void *value, size_t size, int flags) | |
3110 | { | |
3111 | struct inode *inode = d_backing_inode(dentry); | |
3112 | struct inode_security_struct *isec; | |
3113 | struct superblock_security_struct *sbsec; | |
3114 | struct common_audit_data ad; | |
3115 | u32 newsid, sid = current_sid(); | |
3116 | int rc = 0; | |
3117 | ||
3118 | if (strcmp(name, XATTR_NAME_SELINUX)) | |
3119 | return selinux_inode_setotherxattr(dentry, name); | |
3120 | ||
3121 | sbsec = inode->i_sb->s_security; | |
3122 | if (!(sbsec->flags & SBLABEL_MNT)) | |
3123 | return -EOPNOTSUPP; | |
3124 | ||
3125 | if (!inode_owner_or_capable(inode)) | |
3126 | return -EPERM; | |
3127 | ||
3128 | ad.type = LSM_AUDIT_DATA_DENTRY; | |
3129 | ad.u.dentry = dentry; | |
3130 | ||
3131 | isec = backing_inode_security(dentry); | |
3132 | rc = avc_has_perm(sid, isec->sid, isec->sclass, | |
3133 | FILE__RELABELFROM, &ad); | |
3134 | if (rc) | |
3135 | return rc; | |
3136 | ||
3137 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); | |
3138 | if (rc == -EINVAL) { | |
3139 | if (!capable(CAP_MAC_ADMIN)) { | |
3140 | struct audit_buffer *ab; | |
3141 | size_t audit_size; | |
3142 | const char *str; | |
3143 | ||
3144 | /* We strip a nul only if it is at the end, otherwise the | |
3145 | * context contains a nul and we should audit that */ | |
3146 | if (value) { | |
3147 | str = value; | |
3148 | if (str[size - 1] == '\0') | |
3149 | audit_size = size - 1; | |
3150 | else | |
3151 | audit_size = size; | |
3152 | } else { | |
3153 | str = ""; | |
3154 | audit_size = 0; | |
3155 | } | |
3156 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
3157 | audit_log_format(ab, "op=setxattr invalid_context="); | |
3158 | audit_log_n_untrustedstring(ab, value, audit_size); | |
3159 | audit_log_end(ab); | |
3160 | ||
3161 | return rc; | |
3162 | } | |
3163 | rc = security_context_to_sid_force(value, size, &newsid); | |
3164 | } | |
3165 | if (rc) | |
3166 | return rc; | |
3167 | ||
3168 | rc = avc_has_perm(sid, newsid, isec->sclass, | |
3169 | FILE__RELABELTO, &ad); | |
3170 | if (rc) | |
3171 | return rc; | |
3172 | ||
3173 | rc = security_validate_transition(isec->sid, newsid, sid, | |
3174 | isec->sclass); | |
3175 | if (rc) | |
3176 | return rc; | |
3177 | ||
3178 | return avc_has_perm(newsid, | |
3179 | sbsec->sid, | |
3180 | SECCLASS_FILESYSTEM, | |
3181 | FILESYSTEM__ASSOCIATE, | |
3182 | &ad); | |
3183 | } | |
3184 | ||
3185 | static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, | |
3186 | const void *value, size_t size, | |
3187 | int flags) | |
3188 | { | |
3189 | struct inode *inode = d_backing_inode(dentry); | |
3190 | struct inode_security_struct *isec; | |
3191 | u32 newsid; | |
3192 | int rc; | |
3193 | ||
3194 | if (strcmp(name, XATTR_NAME_SELINUX)) { | |
3195 | /* Not an attribute we recognize, so nothing to do. */ | |
3196 | return; | |
3197 | } | |
3198 | ||
3199 | rc = security_context_to_sid_force(value, size, &newsid); | |
3200 | if (rc) { | |
3201 | printk(KERN_ERR "SELinux: unable to map context to SID" | |
3202 | "for (%s, %lu), rc=%d\n", | |
3203 | inode->i_sb->s_id, inode->i_ino, -rc); | |
3204 | return; | |
3205 | } | |
3206 | ||
3207 | isec = backing_inode_security(dentry); | |
3208 | spin_lock(&isec->lock); | |
3209 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3210 | isec->sid = newsid; | |
3211 | isec->initialized = LABEL_INITIALIZED; | |
3212 | spin_unlock(&isec->lock); | |
3213 | ||
3214 | return; | |
3215 | } | |
3216 | ||
3217 | static int selinux_inode_getxattr(struct dentry *dentry, const char *name) | |
3218 | { | |
3219 | const struct cred *cred = current_cred(); | |
3220 | ||
3221 | return dentry_has_perm(cred, dentry, FILE__GETATTR); | |
3222 | } | |
3223 | ||
3224 | static int selinux_inode_listxattr(struct dentry *dentry) | |
3225 | { | |
3226 | const struct cred *cred = current_cred(); | |
3227 | ||
3228 | return dentry_has_perm(cred, dentry, FILE__GETATTR); | |
3229 | } | |
3230 | ||
3231 | static int selinux_inode_removexattr(struct dentry *dentry, const char *name) | |
3232 | { | |
3233 | if (strcmp(name, XATTR_NAME_SELINUX)) | |
3234 | return selinux_inode_setotherxattr(dentry, name); | |
3235 | ||
3236 | /* No one is allowed to remove a SELinux security label. | |
3237 | You can change the label, but all data must be labeled. */ | |
3238 | return -EACCES; | |
3239 | } | |
3240 | ||
3241 | /* | |
3242 | * Copy the inode security context value to the user. | |
3243 | * | |
3244 | * Permission check is handled by selinux_inode_getxattr hook. | |
3245 | */ | |
3246 | static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) | |
3247 | { | |
3248 | u32 size; | |
3249 | int error; | |
3250 | char *context = NULL; | |
3251 | struct inode_security_struct *isec; | |
3252 | ||
3253 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3254 | return -EOPNOTSUPP; | |
3255 | ||
3256 | /* | |
3257 | * If the caller has CAP_MAC_ADMIN, then get the raw context | |
3258 | * value even if it is not defined by current policy; otherwise, | |
3259 | * use the in-core value under current policy. | |
3260 | * Use the non-auditing forms of the permission checks since | |
3261 | * getxattr may be called by unprivileged processes commonly | |
3262 | * and lack of permission just means that we fall back to the | |
3263 | * in-core context value, not a denial. | |
3264 | */ | |
3265 | error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN, | |
3266 | SECURITY_CAP_NOAUDIT); | |
3267 | if (!error) | |
3268 | error = cred_has_capability(current_cred(), CAP_MAC_ADMIN, | |
3269 | SECURITY_CAP_NOAUDIT, true); | |
3270 | isec = inode_security(inode); | |
3271 | if (!error) | |
3272 | error = security_sid_to_context_force(isec->sid, &context, | |
3273 | &size); | |
3274 | else | |
3275 | error = security_sid_to_context(isec->sid, &context, &size); | |
3276 | if (error) | |
3277 | return error; | |
3278 | error = size; | |
3279 | if (alloc) { | |
3280 | *buffer = context; | |
3281 | goto out_nofree; | |
3282 | } | |
3283 | kfree(context); | |
3284 | out_nofree: | |
3285 | return error; | |
3286 | } | |
3287 | ||
3288 | static int selinux_inode_setsecurity(struct inode *inode, const char *name, | |
3289 | const void *value, size_t size, int flags) | |
3290 | { | |
3291 | struct inode_security_struct *isec = inode_security_novalidate(inode); | |
3292 | u32 newsid; | |
3293 | int rc; | |
3294 | ||
3295 | if (strcmp(name, XATTR_SELINUX_SUFFIX)) | |
3296 | return -EOPNOTSUPP; | |
3297 | ||
3298 | if (!value || !size) | |
3299 | return -EACCES; | |
3300 | ||
3301 | rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); | |
3302 | if (rc) | |
3303 | return rc; | |
3304 | ||
3305 | spin_lock(&isec->lock); | |
3306 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3307 | isec->sid = newsid; | |
3308 | isec->initialized = LABEL_INITIALIZED; | |
3309 | spin_unlock(&isec->lock); | |
3310 | return 0; | |
3311 | } | |
3312 | ||
3313 | static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) | |
3314 | { | |
3315 | const int len = sizeof(XATTR_NAME_SELINUX); | |
3316 | if (buffer && len <= buffer_size) | |
3317 | memcpy(buffer, XATTR_NAME_SELINUX, len); | |
3318 | return len; | |
3319 | } | |
3320 | ||
3321 | static void selinux_inode_getsecid(struct inode *inode, u32 *secid) | |
3322 | { | |
3323 | struct inode_security_struct *isec = inode_security_novalidate(inode); | |
3324 | *secid = isec->sid; | |
3325 | } | |
3326 | ||
3327 | static int selinux_inode_copy_up(struct dentry *src, struct cred **new) | |
3328 | { | |
3329 | u32 sid; | |
3330 | struct task_security_struct *tsec; | |
3331 | struct cred *new_creds = *new; | |
3332 | ||
3333 | if (new_creds == NULL) { | |
3334 | new_creds = prepare_creds(); | |
3335 | if (!new_creds) | |
3336 | return -ENOMEM; | |
3337 | } | |
3338 | ||
3339 | tsec = new_creds->security; | |
3340 | /* Get label from overlay inode and set it in create_sid */ | |
3341 | selinux_inode_getsecid(d_inode(src), &sid); | |
3342 | tsec->create_sid = sid; | |
3343 | *new = new_creds; | |
3344 | return 0; | |
3345 | } | |
3346 | ||
3347 | static int selinux_inode_copy_up_xattr(const char *name) | |
3348 | { | |
3349 | /* The copy_up hook above sets the initial context on an inode, but we | |
3350 | * don't then want to overwrite it by blindly copying all the lower | |
3351 | * xattrs up. Instead, we have to filter out SELinux-related xattrs. | |
3352 | */ | |
3353 | if (strcmp(name, XATTR_NAME_SELINUX) == 0) | |
3354 | return 1; /* Discard */ | |
3355 | /* | |
3356 | * Any other attribute apart from SELINUX is not claimed, supported | |
3357 | * by selinux. | |
3358 | */ | |
3359 | return -EOPNOTSUPP; | |
3360 | } | |
3361 | ||
3362 | /* file security operations */ | |
3363 | ||
3364 | static int selinux_revalidate_file_permission(struct file *file, int mask) | |
3365 | { | |
3366 | const struct cred *cred = current_cred(); | |
3367 | struct inode *inode = file_inode(file); | |
3368 | ||
3369 | /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */ | |
3370 | if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE)) | |
3371 | mask |= MAY_APPEND; | |
3372 | ||
3373 | return file_has_perm(cred, file, | |
3374 | file_mask_to_av(inode->i_mode, mask)); | |
3375 | } | |
3376 | ||
3377 | static int selinux_file_permission(struct file *file, int mask) | |
3378 | { | |
3379 | struct inode *inode = file_inode(file); | |
3380 | struct file_security_struct *fsec = file->f_security; | |
3381 | struct inode_security_struct *isec; | |
3382 | u32 sid = current_sid(); | |
3383 | ||
3384 | if (!mask) | |
3385 | /* No permission to check. Existence test. */ | |
3386 | return 0; | |
3387 | ||
3388 | isec = inode_security(inode); | |
3389 | if (sid == fsec->sid && fsec->isid == isec->sid && | |
3390 | fsec->pseqno == avc_policy_seqno()) | |
3391 | /* No change since file_open check. */ | |
3392 | return 0; | |
3393 | ||
3394 | return selinux_revalidate_file_permission(file, mask); | |
3395 | } | |
3396 | ||
3397 | static int selinux_file_alloc_security(struct file *file) | |
3398 | { | |
3399 | return file_alloc_security(file); | |
3400 | } | |
3401 | ||
3402 | static void selinux_file_free_security(struct file *file) | |
3403 | { | |
3404 | file_free_security(file); | |
3405 | } | |
3406 | ||
3407 | /* | |
3408 | * Check whether a task has the ioctl permission and cmd | |
3409 | * operation to an inode. | |
3410 | */ | |
3411 | static int ioctl_has_perm(const struct cred *cred, struct file *file, | |
3412 | u32 requested, u16 cmd) | |
3413 | { | |
3414 | struct common_audit_data ad; | |
3415 | struct file_security_struct *fsec = file->f_security; | |
3416 | struct inode *inode = file_inode(file); | |
3417 | struct inode_security_struct *isec; | |
3418 | struct lsm_ioctlop_audit ioctl; | |
3419 | u32 ssid = cred_sid(cred); | |
3420 | int rc; | |
3421 | u8 driver = cmd >> 8; | |
3422 | u8 xperm = cmd & 0xff; | |
3423 | ||
3424 | ad.type = LSM_AUDIT_DATA_IOCTL_OP; | |
3425 | ad.u.op = &ioctl; | |
3426 | ad.u.op->cmd = cmd; | |
3427 | ad.u.op->path = file->f_path; | |
3428 | ||
3429 | if (ssid != fsec->sid) { | |
3430 | rc = avc_has_perm(ssid, fsec->sid, | |
3431 | SECCLASS_FD, | |
3432 | FD__USE, | |
3433 | &ad); | |
3434 | if (rc) | |
3435 | goto out; | |
3436 | } | |
3437 | ||
3438 | if (unlikely(IS_PRIVATE(inode))) | |
3439 | return 0; | |
3440 | ||
3441 | isec = inode_security(inode); | |
3442 | rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, | |
3443 | requested, driver, xperm, &ad); | |
3444 | out: | |
3445 | return rc; | |
3446 | } | |
3447 | ||
3448 | static int selinux_file_ioctl(struct file *file, unsigned int cmd, | |
3449 | unsigned long arg) | |
3450 | { | |
3451 | const struct cred *cred = current_cred(); | |
3452 | int error = 0; | |
3453 | ||
3454 | switch (cmd) { | |
3455 | case FIONREAD: | |
3456 | /* fall through */ | |
3457 | case FIBMAP: | |
3458 | /* fall through */ | |
3459 | case FIGETBSZ: | |
3460 | /* fall through */ | |
3461 | case FS_IOC_GETFLAGS: | |
3462 | /* fall through */ | |
3463 | case FS_IOC_GETVERSION: | |
3464 | error = file_has_perm(cred, file, FILE__GETATTR); | |
3465 | break; | |
3466 | ||
3467 | case FS_IOC_SETFLAGS: | |
3468 | /* fall through */ | |
3469 | case FS_IOC_SETVERSION: | |
3470 | error = file_has_perm(cred, file, FILE__SETATTR); | |
3471 | break; | |
3472 | ||
3473 | /* sys_ioctl() checks */ | |
3474 | case FIONBIO: | |
3475 | /* fall through */ | |
3476 | case FIOASYNC: | |
3477 | error = file_has_perm(cred, file, 0); | |
3478 | break; | |
3479 | ||
3480 | case KDSKBENT: | |
3481 | case KDSKBSENT: | |
3482 | error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG, | |
3483 | SECURITY_CAP_AUDIT, true); | |
3484 | break; | |
3485 | ||
3486 | /* default case assumes that the command will go | |
3487 | * to the file's ioctl() function. | |
3488 | */ | |
3489 | default: | |
3490 | error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); | |
3491 | } | |
3492 | return error; | |
3493 | } | |
3494 | ||
3495 | static int default_noexec; | |
3496 | ||
3497 | static int file_map_prot_check(struct file *file, unsigned long prot, int shared) | |
3498 | { | |
3499 | const struct cred *cred = current_cred(); | |
3500 | u32 sid = cred_sid(cred); | |
3501 | int rc = 0; | |
3502 | ||
3503 | if (default_noexec && | |
3504 | (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) || | |
3505 | (!shared && (prot & PROT_WRITE)))) { | |
3506 | /* | |
3507 | * We are making executable an anonymous mapping or a | |
3508 | * private file mapping that will also be writable. | |
3509 | * This has an additional check. | |
3510 | */ | |
3511 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, | |
3512 | PROCESS__EXECMEM, NULL); | |
3513 | if (rc) | |
3514 | goto error; | |
3515 | } | |
3516 | ||
3517 | if (file) { | |
3518 | /* read access is always possible with a mapping */ | |
3519 | u32 av = FILE__READ; | |
3520 | ||
3521 | /* write access only matters if the mapping is shared */ | |
3522 | if (shared && (prot & PROT_WRITE)) | |
3523 | av |= FILE__WRITE; | |
3524 | ||
3525 | if (prot & PROT_EXEC) | |
3526 | av |= FILE__EXECUTE; | |
3527 | ||
3528 | return file_has_perm(cred, file, av); | |
3529 | } | |
3530 | ||
3531 | error: | |
3532 | return rc; | |
3533 | } | |
3534 | ||
3535 | static int selinux_mmap_addr(unsigned long addr) | |
3536 | { | |
3537 | int rc = 0; | |
3538 | ||
3539 | if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { | |
3540 | u32 sid = current_sid(); | |
3541 | rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, | |
3542 | MEMPROTECT__MMAP_ZERO, NULL); | |
3543 | } | |
3544 | ||
3545 | return rc; | |
3546 | } | |
3547 | ||
3548 | static int selinux_mmap_file(struct file *file, unsigned long reqprot, | |
3549 | unsigned long prot, unsigned long flags) | |
3550 | { | |
3551 | if (selinux_checkreqprot) | |
3552 | prot = reqprot; | |
3553 | ||
3554 | return file_map_prot_check(file, prot, | |
3555 | (flags & MAP_TYPE) == MAP_SHARED); | |
3556 | } | |
3557 | ||
3558 | static int selinux_file_mprotect(struct vm_area_struct *vma, | |
3559 | unsigned long reqprot, | |
3560 | unsigned long prot) | |
3561 | { | |
3562 | const struct cred *cred = current_cred(); | |
3563 | u32 sid = cred_sid(cred); | |
3564 | ||
3565 | if (selinux_checkreqprot) | |
3566 | prot = reqprot; | |
3567 | ||
3568 | if (default_noexec && | |
3569 | (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) { | |
3570 | int rc = 0; | |
3571 | if (vma->vm_start >= vma->vm_mm->start_brk && | |
3572 | vma->vm_end <= vma->vm_mm->brk) { | |
3573 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, | |
3574 | PROCESS__EXECHEAP, NULL); | |
3575 | } else if (!vma->vm_file && | |
3576 | ((vma->vm_start <= vma->vm_mm->start_stack && | |
3577 | vma->vm_end >= vma->vm_mm->start_stack) || | |
3578 | vma_is_stack_for_current(vma))) { | |
3579 | rc = avc_has_perm(sid, sid, SECCLASS_PROCESS, | |
3580 | PROCESS__EXECSTACK, NULL); | |
3581 | } else if (vma->vm_file && vma->anon_vma) { | |
3582 | /* | |
3583 | * We are making executable a file mapping that has | |
3584 | * had some COW done. Since pages might have been | |
3585 | * written, check ability to execute the possibly | |
3586 | * modified content. This typically should only | |
3587 | * occur for text relocations. | |
3588 | */ | |
3589 | rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD); | |
3590 | } | |
3591 | if (rc) | |
3592 | return rc; | |
3593 | } | |
3594 | ||
3595 | return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED); | |
3596 | } | |
3597 | ||
3598 | static int selinux_file_lock(struct file *file, unsigned int cmd) | |
3599 | { | |
3600 | const struct cred *cred = current_cred(); | |
3601 | ||
3602 | return file_has_perm(cred, file, FILE__LOCK); | |
3603 | } | |
3604 | ||
3605 | static int selinux_file_fcntl(struct file *file, unsigned int cmd, | |
3606 | unsigned long arg) | |
3607 | { | |
3608 | const struct cred *cred = current_cred(); | |
3609 | int err = 0; | |
3610 | ||
3611 | switch (cmd) { | |
3612 | case F_SETFL: | |
3613 | if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) { | |
3614 | err = file_has_perm(cred, file, FILE__WRITE); | |
3615 | break; | |
3616 | } | |
3617 | /* fall through */ | |
3618 | case F_SETOWN: | |
3619 | case F_SETSIG: | |
3620 | case F_GETFL: | |
3621 | case F_GETOWN: | |
3622 | case F_GETSIG: | |
3623 | case F_GETOWNER_UIDS: | |
3624 | /* Just check FD__USE permission */ | |
3625 | err = file_has_perm(cred, file, 0); | |
3626 | break; | |
3627 | case F_GETLK: | |
3628 | case F_SETLK: | |
3629 | case F_SETLKW: | |
3630 | case F_OFD_GETLK: | |
3631 | case F_OFD_SETLK: | |
3632 | case F_OFD_SETLKW: | |
3633 | #if BITS_PER_LONG == 32 | |
3634 | case F_GETLK64: | |
3635 | case F_SETLK64: | |
3636 | case F_SETLKW64: | |
3637 | #endif | |
3638 | err = file_has_perm(cred, file, FILE__LOCK); | |
3639 | break; | |
3640 | } | |
3641 | ||
3642 | return err; | |
3643 | } | |
3644 | ||
3645 | static void selinux_file_set_fowner(struct file *file) | |
3646 | { | |
3647 | struct file_security_struct *fsec; | |
3648 | ||
3649 | fsec = file->f_security; | |
3650 | fsec->fown_sid = current_sid(); | |
3651 | } | |
3652 | ||
3653 | static int selinux_file_send_sigiotask(struct task_struct *tsk, | |
3654 | struct fown_struct *fown, int signum) | |
3655 | { | |
3656 | struct file *file; | |
3657 | u32 sid = task_sid(tsk); | |
3658 | u32 perm; | |
3659 | struct file_security_struct *fsec; | |
3660 | ||
3661 | /* struct fown_struct is never outside the context of a struct file */ | |
3662 | file = container_of(fown, struct file, f_owner); | |
3663 | ||
3664 | fsec = file->f_security; | |
3665 | ||
3666 | if (!signum) | |
3667 | perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */ | |
3668 | else | |
3669 | perm = signal_to_av(signum); | |
3670 | ||
3671 | return avc_has_perm(fsec->fown_sid, sid, | |
3672 | SECCLASS_PROCESS, perm, NULL); | |
3673 | } | |
3674 | ||
3675 | static int selinux_file_receive(struct file *file) | |
3676 | { | |
3677 | const struct cred *cred = current_cred(); | |
3678 | ||
3679 | return file_has_perm(cred, file, file_to_av(file)); | |
3680 | } | |
3681 | ||
3682 | static int selinux_file_open(struct file *file, const struct cred *cred) | |
3683 | { | |
3684 | struct file_security_struct *fsec; | |
3685 | struct inode_security_struct *isec; | |
3686 | ||
3687 | fsec = file->f_security; | |
3688 | isec = inode_security(file_inode(file)); | |
3689 | /* | |
3690 | * Save inode label and policy sequence number | |
3691 | * at open-time so that selinux_file_permission | |
3692 | * can determine whether revalidation is necessary. | |
3693 | * Task label is already saved in the file security | |
3694 | * struct as its SID. | |
3695 | */ | |
3696 | fsec->isid = isec->sid; | |
3697 | fsec->pseqno = avc_policy_seqno(); | |
3698 | /* | |
3699 | * Since the inode label or policy seqno may have changed | |
3700 | * between the selinux_inode_permission check and the saving | |
3701 | * of state above, recheck that access is still permitted. | |
3702 | * Otherwise, access might never be revalidated against the | |
3703 | * new inode label or new policy. | |
3704 | * This check is not redundant - do not remove. | |
3705 | */ | |
3706 | return file_path_has_perm(cred, file, open_file_to_av(file)); | |
3707 | } | |
3708 | ||
3709 | /* task security operations */ | |
3710 | ||
3711 | static int selinux_task_create(unsigned long clone_flags) | |
3712 | { | |
3713 | u32 sid = current_sid(); | |
3714 | ||
3715 | return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL); | |
3716 | } | |
3717 | ||
3718 | /* | |
3719 | * allocate the SELinux part of blank credentials | |
3720 | */ | |
3721 | static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp) | |
3722 | { | |
3723 | struct task_security_struct *tsec; | |
3724 | ||
3725 | tsec = kzalloc(sizeof(struct task_security_struct), gfp); | |
3726 | if (!tsec) | |
3727 | return -ENOMEM; | |
3728 | ||
3729 | cred->security = tsec; | |
3730 | return 0; | |
3731 | } | |
3732 | ||
3733 | /* | |
3734 | * detach and free the LSM part of a set of credentials | |
3735 | */ | |
3736 | static void selinux_cred_free(struct cred *cred) | |
3737 | { | |
3738 | struct task_security_struct *tsec = cred->security; | |
3739 | ||
3740 | /* | |
3741 | * cred->security == NULL if security_cred_alloc_blank() or | |
3742 | * security_prepare_creds() returned an error. | |
3743 | */ | |
3744 | BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE); | |
3745 | cred->security = (void *) 0x7UL; | |
3746 | kfree(tsec); | |
3747 | } | |
3748 | ||
3749 | /* | |
3750 | * prepare a new set of credentials for modification | |
3751 | */ | |
3752 | static int selinux_cred_prepare(struct cred *new, const struct cred *old, | |
3753 | gfp_t gfp) | |
3754 | { | |
3755 | const struct task_security_struct *old_tsec; | |
3756 | struct task_security_struct *tsec; | |
3757 | ||
3758 | old_tsec = old->security; | |
3759 | ||
3760 | tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp); | |
3761 | if (!tsec) | |
3762 | return -ENOMEM; | |
3763 | ||
3764 | new->security = tsec; | |
3765 | return 0; | |
3766 | } | |
3767 | ||
3768 | /* | |
3769 | * transfer the SELinux data to a blank set of creds | |
3770 | */ | |
3771 | static void selinux_cred_transfer(struct cred *new, const struct cred *old) | |
3772 | { | |
3773 | const struct task_security_struct *old_tsec = old->security; | |
3774 | struct task_security_struct *tsec = new->security; | |
3775 | ||
3776 | *tsec = *old_tsec; | |
3777 | } | |
3778 | ||
3779 | /* | |
3780 | * set the security data for a kernel service | |
3781 | * - all the creation contexts are set to unlabelled | |
3782 | */ | |
3783 | static int selinux_kernel_act_as(struct cred *new, u32 secid) | |
3784 | { | |
3785 | struct task_security_struct *tsec = new->security; | |
3786 | u32 sid = current_sid(); | |
3787 | int ret; | |
3788 | ||
3789 | ret = avc_has_perm(sid, secid, | |
3790 | SECCLASS_KERNEL_SERVICE, | |
3791 | KERNEL_SERVICE__USE_AS_OVERRIDE, | |
3792 | NULL); | |
3793 | if (ret == 0) { | |
3794 | tsec->sid = secid; | |
3795 | tsec->create_sid = 0; | |
3796 | tsec->keycreate_sid = 0; | |
3797 | tsec->sockcreate_sid = 0; | |
3798 | } | |
3799 | return ret; | |
3800 | } | |
3801 | ||
3802 | /* | |
3803 | * set the file creation context in a security record to the same as the | |
3804 | * objective context of the specified inode | |
3805 | */ | |
3806 | static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode) | |
3807 | { | |
3808 | struct inode_security_struct *isec = inode_security(inode); | |
3809 | struct task_security_struct *tsec = new->security; | |
3810 | u32 sid = current_sid(); | |
3811 | int ret; | |
3812 | ||
3813 | ret = avc_has_perm(sid, isec->sid, | |
3814 | SECCLASS_KERNEL_SERVICE, | |
3815 | KERNEL_SERVICE__CREATE_FILES_AS, | |
3816 | NULL); | |
3817 | ||
3818 | if (ret == 0) | |
3819 | tsec->create_sid = isec->sid; | |
3820 | return ret; | |
3821 | } | |
3822 | ||
3823 | static int selinux_kernel_module_request(char *kmod_name) | |
3824 | { | |
3825 | struct common_audit_data ad; | |
3826 | ||
3827 | ad.type = LSM_AUDIT_DATA_KMOD; | |
3828 | ad.u.kmod_name = kmod_name; | |
3829 | ||
3830 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM, | |
3831 | SYSTEM__MODULE_REQUEST, &ad); | |
3832 | } | |
3833 | ||
3834 | static int selinux_kernel_module_from_file(struct file *file) | |
3835 | { | |
3836 | struct common_audit_data ad; | |
3837 | struct inode_security_struct *isec; | |
3838 | struct file_security_struct *fsec; | |
3839 | u32 sid = current_sid(); | |
3840 | int rc; | |
3841 | ||
3842 | /* init_module */ | |
3843 | if (file == NULL) | |
3844 | return avc_has_perm(sid, sid, SECCLASS_SYSTEM, | |
3845 | SYSTEM__MODULE_LOAD, NULL); | |
3846 | ||
3847 | /* finit_module */ | |
3848 | ||
3849 | ad.type = LSM_AUDIT_DATA_FILE; | |
3850 | ad.u.file = file; | |
3851 | ||
3852 | fsec = file->f_security; | |
3853 | if (sid != fsec->sid) { | |
3854 | rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad); | |
3855 | if (rc) | |
3856 | return rc; | |
3857 | } | |
3858 | ||
3859 | isec = inode_security(file_inode(file)); | |
3860 | return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM, | |
3861 | SYSTEM__MODULE_LOAD, &ad); | |
3862 | } | |
3863 | ||
3864 | static int selinux_kernel_read_file(struct file *file, | |
3865 | enum kernel_read_file_id id) | |
3866 | { | |
3867 | int rc = 0; | |
3868 | ||
3869 | switch (id) { | |
3870 | case READING_MODULE: | |
3871 | rc = selinux_kernel_module_from_file(file); | |
3872 | break; | |
3873 | default: | |
3874 | break; | |
3875 | } | |
3876 | ||
3877 | return rc; | |
3878 | } | |
3879 | ||
3880 | static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) | |
3881 | { | |
3882 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3883 | PROCESS__SETPGID, NULL); | |
3884 | } | |
3885 | ||
3886 | static int selinux_task_getpgid(struct task_struct *p) | |
3887 | { | |
3888 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3889 | PROCESS__GETPGID, NULL); | |
3890 | } | |
3891 | ||
3892 | static int selinux_task_getsid(struct task_struct *p) | |
3893 | { | |
3894 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3895 | PROCESS__GETSESSION, NULL); | |
3896 | } | |
3897 | ||
3898 | static void selinux_task_getsecid(struct task_struct *p, u32 *secid) | |
3899 | { | |
3900 | *secid = task_sid(p); | |
3901 | } | |
3902 | ||
3903 | static int selinux_task_setnice(struct task_struct *p, int nice) | |
3904 | { | |
3905 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3906 | PROCESS__SETSCHED, NULL); | |
3907 | } | |
3908 | ||
3909 | static int selinux_task_setioprio(struct task_struct *p, int ioprio) | |
3910 | { | |
3911 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3912 | PROCESS__SETSCHED, NULL); | |
3913 | } | |
3914 | ||
3915 | static int selinux_task_getioprio(struct task_struct *p) | |
3916 | { | |
3917 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3918 | PROCESS__GETSCHED, NULL); | |
3919 | } | |
3920 | ||
3921 | static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource, | |
3922 | struct rlimit *new_rlim) | |
3923 | { | |
3924 | struct rlimit *old_rlim = p->signal->rlim + resource; | |
3925 | ||
3926 | /* Control the ability to change the hard limit (whether | |
3927 | lowering or raising it), so that the hard limit can | |
3928 | later be used as a safe reset point for the soft limit | |
3929 | upon context transitions. See selinux_bprm_committing_creds. */ | |
3930 | if (old_rlim->rlim_max != new_rlim->rlim_max) | |
3931 | return avc_has_perm(current_sid(), task_sid(p), | |
3932 | SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL); | |
3933 | ||
3934 | return 0; | |
3935 | } | |
3936 | ||
3937 | static int selinux_task_setscheduler(struct task_struct *p) | |
3938 | { | |
3939 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3940 | PROCESS__SETSCHED, NULL); | |
3941 | } | |
3942 | ||
3943 | static int selinux_task_getscheduler(struct task_struct *p) | |
3944 | { | |
3945 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3946 | PROCESS__GETSCHED, NULL); | |
3947 | } | |
3948 | ||
3949 | static int selinux_task_movememory(struct task_struct *p) | |
3950 | { | |
3951 | return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS, | |
3952 | PROCESS__SETSCHED, NULL); | |
3953 | } | |
3954 | ||
3955 | static int selinux_task_kill(struct task_struct *p, struct siginfo *info, | |
3956 | int sig, u32 secid) | |
3957 | { | |
3958 | u32 perm; | |
3959 | ||
3960 | if (!sig) | |
3961 | perm = PROCESS__SIGNULL; /* null signal; existence test */ | |
3962 | else | |
3963 | perm = signal_to_av(sig); | |
3964 | if (!secid) | |
3965 | secid = current_sid(); | |
3966 | return avc_has_perm(secid, task_sid(p), SECCLASS_PROCESS, perm, NULL); | |
3967 | } | |
3968 | ||
3969 | static void selinux_task_to_inode(struct task_struct *p, | |
3970 | struct inode *inode) | |
3971 | { | |
3972 | struct inode_security_struct *isec = inode->i_security; | |
3973 | u32 sid = task_sid(p); | |
3974 | ||
3975 | spin_lock(&isec->lock); | |
3976 | isec->sclass = inode_mode_to_security_class(inode->i_mode); | |
3977 | isec->sid = sid; | |
3978 | isec->initialized = LABEL_INITIALIZED; | |
3979 | spin_unlock(&isec->lock); | |
3980 | } | |
3981 | ||
3982 | /* Returns error only if unable to parse addresses */ | |
3983 | static int selinux_parse_skb_ipv4(struct sk_buff *skb, | |
3984 | struct common_audit_data *ad, u8 *proto) | |
3985 | { | |
3986 | int offset, ihlen, ret = -EINVAL; | |
3987 | struct iphdr _iph, *ih; | |
3988 | ||
3989 | offset = skb_network_offset(skb); | |
3990 | ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph); | |
3991 | if (ih == NULL) | |
3992 | goto out; | |
3993 | ||
3994 | ihlen = ih->ihl * 4; | |
3995 | if (ihlen < sizeof(_iph)) | |
3996 | goto out; | |
3997 | ||
3998 | ad->u.net->v4info.saddr = ih->saddr; | |
3999 | ad->u.net->v4info.daddr = ih->daddr; | |
4000 | ret = 0; | |
4001 | ||
4002 | if (proto) | |
4003 | *proto = ih->protocol; | |
4004 | ||
4005 | switch (ih->protocol) { | |
4006 | case IPPROTO_TCP: { | |
4007 | struct tcphdr _tcph, *th; | |
4008 | ||
4009 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
4010 | break; | |
4011 | ||
4012 | offset += ihlen; | |
4013 | th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); | |
4014 | if (th == NULL) | |
4015 | break; | |
4016 | ||
4017 | ad->u.net->sport = th->source; | |
4018 | ad->u.net->dport = th->dest; | |
4019 | break; | |
4020 | } | |
4021 | ||
4022 | case IPPROTO_UDP: { | |
4023 | struct udphdr _udph, *uh; | |
4024 | ||
4025 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
4026 | break; | |
4027 | ||
4028 | offset += ihlen; | |
4029 | uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); | |
4030 | if (uh == NULL) | |
4031 | break; | |
4032 | ||
4033 | ad->u.net->sport = uh->source; | |
4034 | ad->u.net->dport = uh->dest; | |
4035 | break; | |
4036 | } | |
4037 | ||
4038 | case IPPROTO_DCCP: { | |
4039 | struct dccp_hdr _dccph, *dh; | |
4040 | ||
4041 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
4042 | break; | |
4043 | ||
4044 | offset += ihlen; | |
4045 | dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); | |
4046 | if (dh == NULL) | |
4047 | break; | |
4048 | ||
4049 | ad->u.net->sport = dh->dccph_sport; | |
4050 | ad->u.net->dport = dh->dccph_dport; | |
4051 | break; | |
4052 | } | |
4053 | ||
4054 | default: | |
4055 | break; | |
4056 | } | |
4057 | out: | |
4058 | return ret; | |
4059 | } | |
4060 | ||
4061 | #if IS_ENABLED(CONFIG_IPV6) | |
4062 | ||
4063 | /* Returns error only if unable to parse addresses */ | |
4064 | static int selinux_parse_skb_ipv6(struct sk_buff *skb, | |
4065 | struct common_audit_data *ad, u8 *proto) | |
4066 | { | |
4067 | u8 nexthdr; | |
4068 | int ret = -EINVAL, offset; | |
4069 | struct ipv6hdr _ipv6h, *ip6; | |
4070 | __be16 frag_off; | |
4071 | ||
4072 | offset = skb_network_offset(skb); | |
4073 | ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); | |
4074 | if (ip6 == NULL) | |
4075 | goto out; | |
4076 | ||
4077 | ad->u.net->v6info.saddr = ip6->saddr; | |
4078 | ad->u.net->v6info.daddr = ip6->daddr; | |
4079 | ret = 0; | |
4080 | ||
4081 | nexthdr = ip6->nexthdr; | |
4082 | offset += sizeof(_ipv6h); | |
4083 | offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); | |
4084 | if (offset < 0) | |
4085 | goto out; | |
4086 | ||
4087 | if (proto) | |
4088 | *proto = nexthdr; | |
4089 | ||
4090 | switch (nexthdr) { | |
4091 | case IPPROTO_TCP: { | |
4092 | struct tcphdr _tcph, *th; | |
4093 | ||
4094 | th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); | |
4095 | if (th == NULL) | |
4096 | break; | |
4097 | ||
4098 | ad->u.net->sport = th->source; | |
4099 | ad->u.net->dport = th->dest; | |
4100 | break; | |
4101 | } | |
4102 | ||
4103 | case IPPROTO_UDP: { | |
4104 | struct udphdr _udph, *uh; | |
4105 | ||
4106 | uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); | |
4107 | if (uh == NULL) | |
4108 | break; | |
4109 | ||
4110 | ad->u.net->sport = uh->source; | |
4111 | ad->u.net->dport = uh->dest; | |
4112 | break; | |
4113 | } | |
4114 | ||
4115 | case IPPROTO_DCCP: { | |
4116 | struct dccp_hdr _dccph, *dh; | |
4117 | ||
4118 | dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); | |
4119 | if (dh == NULL) | |
4120 | break; | |
4121 | ||
4122 | ad->u.net->sport = dh->dccph_sport; | |
4123 | ad->u.net->dport = dh->dccph_dport; | |
4124 | break; | |
4125 | } | |
4126 | ||
4127 | /* includes fragments */ | |
4128 | default: | |
4129 | break; | |
4130 | } | |
4131 | out: | |
4132 | return ret; | |
4133 | } | |
4134 | ||
4135 | #endif /* IPV6 */ | |
4136 | ||
4137 | static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad, | |
4138 | char **_addrp, int src, u8 *proto) | |
4139 | { | |
4140 | char *addrp; | |
4141 | int ret; | |
4142 | ||
4143 | switch (ad->u.net->family) { | |
4144 | case PF_INET: | |
4145 | ret = selinux_parse_skb_ipv4(skb, ad, proto); | |
4146 | if (ret) | |
4147 | goto parse_error; | |
4148 | addrp = (char *)(src ? &ad->u.net->v4info.saddr : | |
4149 | &ad->u.net->v4info.daddr); | |
4150 | goto okay; | |
4151 | ||
4152 | #if IS_ENABLED(CONFIG_IPV6) | |
4153 | case PF_INET6: | |
4154 | ret = selinux_parse_skb_ipv6(skb, ad, proto); | |
4155 | if (ret) | |
4156 | goto parse_error; | |
4157 | addrp = (char *)(src ? &ad->u.net->v6info.saddr : | |
4158 | &ad->u.net->v6info.daddr); | |
4159 | goto okay; | |
4160 | #endif /* IPV6 */ | |
4161 | default: | |
4162 | addrp = NULL; | |
4163 | goto okay; | |
4164 | } | |
4165 | ||
4166 | parse_error: | |
4167 | printk(KERN_WARNING | |
4168 | "SELinux: failure in selinux_parse_skb()," | |
4169 | " unable to parse packet\n"); | |
4170 | return ret; | |
4171 | ||
4172 | okay: | |
4173 | if (_addrp) | |
4174 | *_addrp = addrp; | |
4175 | return 0; | |
4176 | } | |
4177 | ||
4178 | /** | |
4179 | * selinux_skb_peerlbl_sid - Determine the peer label of a packet | |
4180 | * @skb: the packet | |
4181 | * @family: protocol family | |
4182 | * @sid: the packet's peer label SID | |
4183 | * | |
4184 | * Description: | |
4185 | * Check the various different forms of network peer labeling and determine | |
4186 | * the peer label/SID for the packet; most of the magic actually occurs in | |
4187 | * the security server function security_net_peersid_cmp(). The function | |
4188 | * returns zero if the value in @sid is valid (although it may be SECSID_NULL) | |
4189 | * or -EACCES if @sid is invalid due to inconsistencies with the different | |
4190 | * peer labels. | |
4191 | * | |
4192 | */ | |
4193 | static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid) | |
4194 | { | |
4195 | int err; | |
4196 | u32 xfrm_sid; | |
4197 | u32 nlbl_sid; | |
4198 | u32 nlbl_type; | |
4199 | ||
4200 | err = selinux_xfrm_skb_sid(skb, &xfrm_sid); | |
4201 | if (unlikely(err)) | |
4202 | return -EACCES; | |
4203 | err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid); | |
4204 | if (unlikely(err)) | |
4205 | return -EACCES; | |
4206 | ||
4207 | err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid); | |
4208 | if (unlikely(err)) { | |
4209 | printk(KERN_WARNING | |
4210 | "SELinux: failure in selinux_skb_peerlbl_sid()," | |
4211 | " unable to determine packet's peer label\n"); | |
4212 | return -EACCES; | |
4213 | } | |
4214 | ||
4215 | return 0; | |
4216 | } | |
4217 | ||
4218 | /** | |
4219 | * selinux_conn_sid - Determine the child socket label for a connection | |
4220 | * @sk_sid: the parent socket's SID | |
4221 | * @skb_sid: the packet's SID | |
4222 | * @conn_sid: the resulting connection SID | |
4223 | * | |
4224 | * If @skb_sid is valid then the user:role:type information from @sk_sid is | |
4225 | * combined with the MLS information from @skb_sid in order to create | |
4226 | * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy | |
4227 | * of @sk_sid. Returns zero on success, negative values on failure. | |
4228 | * | |
4229 | */ | |
4230 | static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid) | |
4231 | { | |
4232 | int err = 0; | |
4233 | ||
4234 | if (skb_sid != SECSID_NULL) | |
4235 | err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid); | |
4236 | else | |
4237 | *conn_sid = sk_sid; | |
4238 | ||
4239 | return err; | |
4240 | } | |
4241 | ||
4242 | /* socket security operations */ | |
4243 | ||
4244 | static int socket_sockcreate_sid(const struct task_security_struct *tsec, | |
4245 | u16 secclass, u32 *socksid) | |
4246 | { | |
4247 | if (tsec->sockcreate_sid > SECSID_NULL) { | |
4248 | *socksid = tsec->sockcreate_sid; | |
4249 | return 0; | |
4250 | } | |
4251 | ||
4252 | return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL, | |
4253 | socksid); | |
4254 | } | |
4255 | ||
4256 | static int sock_has_perm(struct sock *sk, u32 perms) | |
4257 | { | |
4258 | struct sk_security_struct *sksec = sk->sk_security; | |
4259 | struct common_audit_data ad; | |
4260 | struct lsm_network_audit net = {0,}; | |
4261 | ||
4262 | if (sksec->sid == SECINITSID_KERNEL) | |
4263 | return 0; | |
4264 | ||
4265 | ad.type = LSM_AUDIT_DATA_NET; | |
4266 | ad.u.net = &net; | |
4267 | ad.u.net->sk = sk; | |
4268 | ||
4269 | return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms, | |
4270 | &ad); | |
4271 | } | |
4272 | ||
4273 | static int selinux_socket_create(int family, int type, | |
4274 | int protocol, int kern) | |
4275 | { | |
4276 | const struct task_security_struct *tsec = current_security(); | |
4277 | u32 newsid; | |
4278 | u16 secclass; | |
4279 | int rc; | |
4280 | ||
4281 | if (kern) | |
4282 | return 0; | |
4283 | ||
4284 | secclass = socket_type_to_security_class(family, type, protocol); | |
4285 | rc = socket_sockcreate_sid(tsec, secclass, &newsid); | |
4286 | if (rc) | |
4287 | return rc; | |
4288 | ||
4289 | return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL); | |
4290 | } | |
4291 | ||
4292 | static int selinux_socket_post_create(struct socket *sock, int family, | |
4293 | int type, int protocol, int kern) | |
4294 | { | |
4295 | const struct task_security_struct *tsec = current_security(); | |
4296 | struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock)); | |
4297 | struct sk_security_struct *sksec; | |
4298 | u16 sclass = socket_type_to_security_class(family, type, protocol); | |
4299 | u32 sid = SECINITSID_KERNEL; | |
4300 | int err = 0; | |
4301 | ||
4302 | if (!kern) { | |
4303 | err = socket_sockcreate_sid(tsec, sclass, &sid); | |
4304 | if (err) | |
4305 | return err; | |
4306 | } | |
4307 | ||
4308 | isec->sclass = sclass; | |
4309 | isec->sid = sid; | |
4310 | isec->initialized = LABEL_INITIALIZED; | |
4311 | ||
4312 | if (sock->sk) { | |
4313 | sksec = sock->sk->sk_security; | |
4314 | sksec->sclass = sclass; | |
4315 | sksec->sid = sid; | |
4316 | err = selinux_netlbl_socket_post_create(sock->sk, family); | |
4317 | } | |
4318 | ||
4319 | return err; | |
4320 | } | |
4321 | ||
4322 | /* Range of port numbers used to automatically bind. | |
4323 | Need to determine whether we should perform a name_bind | |
4324 | permission check between the socket and the port number. */ | |
4325 | ||
4326 | static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) | |
4327 | { | |
4328 | struct sock *sk = sock->sk; | |
4329 | u16 family; | |
4330 | int err; | |
4331 | ||
4332 | err = sock_has_perm(sk, SOCKET__BIND); | |
4333 | if (err) | |
4334 | goto out; | |
4335 | ||
4336 | /* | |
4337 | * If PF_INET or PF_INET6, check name_bind permission for the port. | |
4338 | * Multiple address binding for SCTP is not supported yet: we just | |
4339 | * check the first address now. | |
4340 | */ | |
4341 | family = sk->sk_family; | |
4342 | if (family == PF_INET || family == PF_INET6) { | |
4343 | char *addrp; | |
4344 | struct sk_security_struct *sksec = sk->sk_security; | |
4345 | struct common_audit_data ad; | |
4346 | struct lsm_network_audit net = {0,}; | |
4347 | struct sockaddr_in *addr4 = NULL; | |
4348 | struct sockaddr_in6 *addr6 = NULL; | |
4349 | unsigned short snum; | |
4350 | u32 sid, node_perm; | |
4351 | ||
4352 | if (family == PF_INET) { | |
4353 | addr4 = (struct sockaddr_in *)address; | |
4354 | snum = ntohs(addr4->sin_port); | |
4355 | addrp = (char *)&addr4->sin_addr.s_addr; | |
4356 | } else { | |
4357 | addr6 = (struct sockaddr_in6 *)address; | |
4358 | snum = ntohs(addr6->sin6_port); | |
4359 | addrp = (char *)&addr6->sin6_addr.s6_addr; | |
4360 | } | |
4361 | ||
4362 | if (snum) { | |
4363 | int low, high; | |
4364 | ||
4365 | inet_get_local_port_range(sock_net(sk), &low, &high); | |
4366 | ||
4367 | if (snum < max(inet_prot_sock(sock_net(sk)), low) || | |
4368 | snum > high) { | |
4369 | err = sel_netport_sid(sk->sk_protocol, | |
4370 | snum, &sid); | |
4371 | if (err) | |
4372 | goto out; | |
4373 | ad.type = LSM_AUDIT_DATA_NET; | |
4374 | ad.u.net = &net; | |
4375 | ad.u.net->sport = htons(snum); | |
4376 | ad.u.net->family = family; | |
4377 | err = avc_has_perm(sksec->sid, sid, | |
4378 | sksec->sclass, | |
4379 | SOCKET__NAME_BIND, &ad); | |
4380 | if (err) | |
4381 | goto out; | |
4382 | } | |
4383 | } | |
4384 | ||
4385 | switch (sksec->sclass) { | |
4386 | case SECCLASS_TCP_SOCKET: | |
4387 | node_perm = TCP_SOCKET__NODE_BIND; | |
4388 | break; | |
4389 | ||
4390 | case SECCLASS_UDP_SOCKET: | |
4391 | node_perm = UDP_SOCKET__NODE_BIND; | |
4392 | break; | |
4393 | ||
4394 | case SECCLASS_DCCP_SOCKET: | |
4395 | node_perm = DCCP_SOCKET__NODE_BIND; | |
4396 | break; | |
4397 | ||
4398 | default: | |
4399 | node_perm = RAWIP_SOCKET__NODE_BIND; | |
4400 | break; | |
4401 | } | |
4402 | ||
4403 | err = sel_netnode_sid(addrp, family, &sid); | |
4404 | if (err) | |
4405 | goto out; | |
4406 | ||
4407 | ad.type = LSM_AUDIT_DATA_NET; | |
4408 | ad.u.net = &net; | |
4409 | ad.u.net->sport = htons(snum); | |
4410 | ad.u.net->family = family; | |
4411 | ||
4412 | if (family == PF_INET) | |
4413 | ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; | |
4414 | else | |
4415 | ad.u.net->v6info.saddr = addr6->sin6_addr; | |
4416 | ||
4417 | err = avc_has_perm(sksec->sid, sid, | |
4418 | sksec->sclass, node_perm, &ad); | |
4419 | if (err) | |
4420 | goto out; | |
4421 | } | |
4422 | out: | |
4423 | return err; | |
4424 | } | |
4425 | ||
4426 | static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen) | |
4427 | { | |
4428 | struct sock *sk = sock->sk; | |
4429 | struct sk_security_struct *sksec = sk->sk_security; | |
4430 | int err; | |
4431 | ||
4432 | err = sock_has_perm(sk, SOCKET__CONNECT); | |
4433 | if (err) | |
4434 | return err; | |
4435 | ||
4436 | /* | |
4437 | * If a TCP or DCCP socket, check name_connect permission for the port. | |
4438 | */ | |
4439 | if (sksec->sclass == SECCLASS_TCP_SOCKET || | |
4440 | sksec->sclass == SECCLASS_DCCP_SOCKET) { | |
4441 | struct common_audit_data ad; | |
4442 | struct lsm_network_audit net = {0,}; | |
4443 | struct sockaddr_in *addr4 = NULL; | |
4444 | struct sockaddr_in6 *addr6 = NULL; | |
4445 | unsigned short snum; | |
4446 | u32 sid, perm; | |
4447 | ||
4448 | if (sk->sk_family == PF_INET) { | |
4449 | addr4 = (struct sockaddr_in *)address; | |
4450 | if (addrlen < sizeof(struct sockaddr_in)) | |
4451 | return -EINVAL; | |
4452 | snum = ntohs(addr4->sin_port); | |
4453 | } else { | |
4454 | addr6 = (struct sockaddr_in6 *)address; | |
4455 | if (addrlen < SIN6_LEN_RFC2133) | |
4456 | return -EINVAL; | |
4457 | snum = ntohs(addr6->sin6_port); | |
4458 | } | |
4459 | ||
4460 | err = sel_netport_sid(sk->sk_protocol, snum, &sid); | |
4461 | if (err) | |
4462 | goto out; | |
4463 | ||
4464 | perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ? | |
4465 | TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT; | |
4466 | ||
4467 | ad.type = LSM_AUDIT_DATA_NET; | |
4468 | ad.u.net = &net; | |
4469 | ad.u.net->dport = htons(snum); | |
4470 | ad.u.net->family = sk->sk_family; | |
4471 | err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad); | |
4472 | if (err) | |
4473 | goto out; | |
4474 | } | |
4475 | ||
4476 | err = selinux_netlbl_socket_connect(sk, address); | |
4477 | ||
4478 | out: | |
4479 | return err; | |
4480 | } | |
4481 | ||
4482 | static int selinux_socket_listen(struct socket *sock, int backlog) | |
4483 | { | |
4484 | return sock_has_perm(sock->sk, SOCKET__LISTEN); | |
4485 | } | |
4486 | ||
4487 | static int selinux_socket_accept(struct socket *sock, struct socket *newsock) | |
4488 | { | |
4489 | int err; | |
4490 | struct inode_security_struct *isec; | |
4491 | struct inode_security_struct *newisec; | |
4492 | u16 sclass; | |
4493 | u32 sid; | |
4494 | ||
4495 | err = sock_has_perm(sock->sk, SOCKET__ACCEPT); | |
4496 | if (err) | |
4497 | return err; | |
4498 | ||
4499 | isec = inode_security_novalidate(SOCK_INODE(sock)); | |
4500 | spin_lock(&isec->lock); | |
4501 | sclass = isec->sclass; | |
4502 | sid = isec->sid; | |
4503 | spin_unlock(&isec->lock); | |
4504 | ||
4505 | newisec = inode_security_novalidate(SOCK_INODE(newsock)); | |
4506 | newisec->sclass = sclass; | |
4507 | newisec->sid = sid; | |
4508 | newisec->initialized = LABEL_INITIALIZED; | |
4509 | ||
4510 | return 0; | |
4511 | } | |
4512 | ||
4513 | static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg, | |
4514 | int size) | |
4515 | { | |
4516 | return sock_has_perm(sock->sk, SOCKET__WRITE); | |
4517 | } | |
4518 | ||
4519 | static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg, | |
4520 | int size, int flags) | |
4521 | { | |
4522 | return sock_has_perm(sock->sk, SOCKET__READ); | |
4523 | } | |
4524 | ||
4525 | static int selinux_socket_getsockname(struct socket *sock) | |
4526 | { | |
4527 | return sock_has_perm(sock->sk, SOCKET__GETATTR); | |
4528 | } | |
4529 | ||
4530 | static int selinux_socket_getpeername(struct socket *sock) | |
4531 | { | |
4532 | return sock_has_perm(sock->sk, SOCKET__GETATTR); | |
4533 | } | |
4534 | ||
4535 | static int selinux_socket_setsockopt(struct socket *sock, int level, int optname) | |
4536 | { | |
4537 | int err; | |
4538 | ||
4539 | err = sock_has_perm(sock->sk, SOCKET__SETOPT); | |
4540 | if (err) | |
4541 | return err; | |
4542 | ||
4543 | return selinux_netlbl_socket_setsockopt(sock, level, optname); | |
4544 | } | |
4545 | ||
4546 | static int selinux_socket_getsockopt(struct socket *sock, int level, | |
4547 | int optname) | |
4548 | { | |
4549 | return sock_has_perm(sock->sk, SOCKET__GETOPT); | |
4550 | } | |
4551 | ||
4552 | static int selinux_socket_shutdown(struct socket *sock, int how) | |
4553 | { | |
4554 | return sock_has_perm(sock->sk, SOCKET__SHUTDOWN); | |
4555 | } | |
4556 | ||
4557 | static int selinux_socket_unix_stream_connect(struct sock *sock, | |
4558 | struct sock *other, | |
4559 | struct sock *newsk) | |
4560 | { | |
4561 | struct sk_security_struct *sksec_sock = sock->sk_security; | |
4562 | struct sk_security_struct *sksec_other = other->sk_security; | |
4563 | struct sk_security_struct *sksec_new = newsk->sk_security; | |
4564 | struct common_audit_data ad; | |
4565 | struct lsm_network_audit net = {0,}; | |
4566 | int err; | |
4567 | ||
4568 | ad.type = LSM_AUDIT_DATA_NET; | |
4569 | ad.u.net = &net; | |
4570 | ad.u.net->sk = other; | |
4571 | ||
4572 | err = avc_has_perm(sksec_sock->sid, sksec_other->sid, | |
4573 | sksec_other->sclass, | |
4574 | UNIX_STREAM_SOCKET__CONNECTTO, &ad); | |
4575 | if (err) | |
4576 | return err; | |
4577 | ||
4578 | /* server child socket */ | |
4579 | sksec_new->peer_sid = sksec_sock->sid; | |
4580 | err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid, | |
4581 | &sksec_new->sid); | |
4582 | if (err) | |
4583 | return err; | |
4584 | ||
4585 | /* connecting socket */ | |
4586 | sksec_sock->peer_sid = sksec_new->sid; | |
4587 | ||
4588 | return 0; | |
4589 | } | |
4590 | ||
4591 | static int selinux_socket_unix_may_send(struct socket *sock, | |
4592 | struct socket *other) | |
4593 | { | |
4594 | struct sk_security_struct *ssec = sock->sk->sk_security; | |
4595 | struct sk_security_struct *osec = other->sk->sk_security; | |
4596 | struct common_audit_data ad; | |
4597 | struct lsm_network_audit net = {0,}; | |
4598 | ||
4599 | ad.type = LSM_AUDIT_DATA_NET; | |
4600 | ad.u.net = &net; | |
4601 | ad.u.net->sk = other->sk; | |
4602 | ||
4603 | return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO, | |
4604 | &ad); | |
4605 | } | |
4606 | ||
4607 | static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex, | |
4608 | char *addrp, u16 family, u32 peer_sid, | |
4609 | struct common_audit_data *ad) | |
4610 | { | |
4611 | int err; | |
4612 | u32 if_sid; | |
4613 | u32 node_sid; | |
4614 | ||
4615 | err = sel_netif_sid(ns, ifindex, &if_sid); | |
4616 | if (err) | |
4617 | return err; | |
4618 | err = avc_has_perm(peer_sid, if_sid, | |
4619 | SECCLASS_NETIF, NETIF__INGRESS, ad); | |
4620 | if (err) | |
4621 | return err; | |
4622 | ||
4623 | err = sel_netnode_sid(addrp, family, &node_sid); | |
4624 | if (err) | |
4625 | return err; | |
4626 | return avc_has_perm(peer_sid, node_sid, | |
4627 | SECCLASS_NODE, NODE__RECVFROM, ad); | |
4628 | } | |
4629 | ||
4630 | static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, | |
4631 | u16 family) | |
4632 | { | |
4633 | int err = 0; | |
4634 | struct sk_security_struct *sksec = sk->sk_security; | |
4635 | u32 sk_sid = sksec->sid; | |
4636 | struct common_audit_data ad; | |
4637 | struct lsm_network_audit net = {0,}; | |
4638 | char *addrp; | |
4639 | ||
4640 | ad.type = LSM_AUDIT_DATA_NET; | |
4641 | ad.u.net = &net; | |
4642 | ad.u.net->netif = skb->skb_iif; | |
4643 | ad.u.net->family = family; | |
4644 | err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); | |
4645 | if (err) | |
4646 | return err; | |
4647 | ||
4648 | if (selinux_secmark_enabled()) { | |
4649 | err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, | |
4650 | PACKET__RECV, &ad); | |
4651 | if (err) | |
4652 | return err; | |
4653 | } | |
4654 | ||
4655 | err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad); | |
4656 | if (err) | |
4657 | return err; | |
4658 | err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad); | |
4659 | ||
4660 | return err; | |
4661 | } | |
4662 | ||
4663 | static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) | |
4664 | { | |
4665 | int err; | |
4666 | struct sk_security_struct *sksec = sk->sk_security; | |
4667 | u16 family = sk->sk_family; | |
4668 | u32 sk_sid = sksec->sid; | |
4669 | struct common_audit_data ad; | |
4670 | struct lsm_network_audit net = {0,}; | |
4671 | char *addrp; | |
4672 | u8 secmark_active; | |
4673 | u8 peerlbl_active; | |
4674 | ||
4675 | if (family != PF_INET && family != PF_INET6) | |
4676 | return 0; | |
4677 | ||
4678 | /* Handle mapped IPv4 packets arriving via IPv6 sockets */ | |
4679 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) | |
4680 | family = PF_INET; | |
4681 | ||
4682 | /* If any sort of compatibility mode is enabled then handoff processing | |
4683 | * to the selinux_sock_rcv_skb_compat() function to deal with the | |
4684 | * special handling. We do this in an attempt to keep this function | |
4685 | * as fast and as clean as possible. */ | |
4686 | if (!selinux_policycap_netpeer) | |
4687 | return selinux_sock_rcv_skb_compat(sk, skb, family); | |
4688 | ||
4689 | secmark_active = selinux_secmark_enabled(); | |
4690 | peerlbl_active = selinux_peerlbl_enabled(); | |
4691 | if (!secmark_active && !peerlbl_active) | |
4692 | return 0; | |
4693 | ||
4694 | ad.type = LSM_AUDIT_DATA_NET; | |
4695 | ad.u.net = &net; | |
4696 | ad.u.net->netif = skb->skb_iif; | |
4697 | ad.u.net->family = family; | |
4698 | err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL); | |
4699 | if (err) | |
4700 | return err; | |
4701 | ||
4702 | if (peerlbl_active) { | |
4703 | u32 peer_sid; | |
4704 | ||
4705 | err = selinux_skb_peerlbl_sid(skb, family, &peer_sid); | |
4706 | if (err) | |
4707 | return err; | |
4708 | err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif, | |
4709 | addrp, family, peer_sid, &ad); | |
4710 | if (err) { | |
4711 | selinux_netlbl_err(skb, family, err, 0); | |
4712 | return err; | |
4713 | } | |
4714 | err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER, | |
4715 | PEER__RECV, &ad); | |
4716 | if (err) { | |
4717 | selinux_netlbl_err(skb, family, err, 0); | |
4718 | return err; | |
4719 | } | |
4720 | } | |
4721 | ||
4722 | if (secmark_active) { | |
4723 | err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET, | |
4724 | PACKET__RECV, &ad); | |
4725 | if (err) | |
4726 | return err; | |
4727 | } | |
4728 | ||
4729 | return err; | |
4730 | } | |
4731 | ||
4732 | static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval, | |
4733 | int __user *optlen, unsigned len) | |
4734 | { | |
4735 | int err = 0; | |
4736 | char *scontext; | |
4737 | u32 scontext_len; | |
4738 | struct sk_security_struct *sksec = sock->sk->sk_security; | |
4739 | u32 peer_sid = SECSID_NULL; | |
4740 | ||
4741 | if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET || | |
4742 | sksec->sclass == SECCLASS_TCP_SOCKET) | |
4743 | peer_sid = sksec->peer_sid; | |
4744 | if (peer_sid == SECSID_NULL) | |
4745 | return -ENOPROTOOPT; | |
4746 | ||
4747 | err = security_sid_to_context(peer_sid, &scontext, &scontext_len); | |
4748 | if (err) | |
4749 | return err; | |
4750 | ||
4751 | if (scontext_len > len) { | |
4752 | err = -ERANGE; | |
4753 | goto out_len; | |
4754 | } | |
4755 | ||
4756 | if (copy_to_user(optval, scontext, scontext_len)) | |
4757 | err = -EFAULT; | |
4758 | ||
4759 | out_len: | |
4760 | if (put_user(scontext_len, optlen)) | |
4761 | err = -EFAULT; | |
4762 | kfree(scontext); | |
4763 | return err; | |
4764 | } | |
4765 | ||
4766 | static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) | |
4767 | { | |
4768 | u32 peer_secid = SECSID_NULL; | |
4769 | u16 family; | |
4770 | struct inode_security_struct *isec; | |
4771 | ||
4772 | if (skb && skb->protocol == htons(ETH_P_IP)) | |
4773 | family = PF_INET; | |
4774 | else if (skb && skb->protocol == htons(ETH_P_IPV6)) | |
4775 | family = PF_INET6; | |
4776 | else if (sock) | |
4777 | family = sock->sk->sk_family; | |
4778 | else | |
4779 | goto out; | |
4780 | ||
4781 | if (sock && family == PF_UNIX) { | |
4782 | isec = inode_security_novalidate(SOCK_INODE(sock)); | |
4783 | peer_secid = isec->sid; | |
4784 | } else if (skb) | |
4785 | selinux_skb_peerlbl_sid(skb, family, &peer_secid); | |
4786 | ||
4787 | out: | |
4788 | *secid = peer_secid; | |
4789 | if (peer_secid == SECSID_NULL) | |
4790 | return -EINVAL; | |
4791 | return 0; | |
4792 | } | |
4793 | ||
4794 | static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) | |
4795 | { | |
4796 | struct sk_security_struct *sksec; | |
4797 | ||
4798 | sksec = kzalloc(sizeof(*sksec), priority); | |
4799 | if (!sksec) | |
4800 | return -ENOMEM; | |
4801 | ||
4802 | sksec->peer_sid = SECINITSID_UNLABELED; | |
4803 | sksec->sid = SECINITSID_UNLABELED; | |
4804 | sksec->sclass = SECCLASS_SOCKET; | |
4805 | selinux_netlbl_sk_security_reset(sksec); | |
4806 | sk->sk_security = sksec; | |
4807 | ||
4808 | return 0; | |
4809 | } | |
4810 | ||
4811 | static void selinux_sk_free_security(struct sock *sk) | |
4812 | { | |
4813 | struct sk_security_struct *sksec = sk->sk_security; | |
4814 | ||
4815 | sk->sk_security = NULL; | |
4816 | selinux_netlbl_sk_security_free(sksec); | |
4817 | kfree(sksec); | |
4818 | } | |
4819 | ||
4820 | static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk) | |
4821 | { | |
4822 | struct sk_security_struct *sksec = sk->sk_security; | |
4823 | struct sk_security_struct *newsksec = newsk->sk_security; | |
4824 | ||
4825 | newsksec->sid = sksec->sid; | |
4826 | newsksec->peer_sid = sksec->peer_sid; | |
4827 | newsksec->sclass = sksec->sclass; | |
4828 | ||
4829 | selinux_netlbl_sk_security_reset(newsksec); | |
4830 | } | |
4831 | ||
4832 | static void selinux_sk_getsecid(struct sock *sk, u32 *secid) | |
4833 | { | |
4834 | if (!sk) | |
4835 | *secid = SECINITSID_ANY_SOCKET; | |
4836 | else { | |
4837 | struct sk_security_struct *sksec = sk->sk_security; | |
4838 | ||
4839 | *secid = sksec->sid; | |
4840 | } | |
4841 | } | |
4842 | ||
4843 | static void selinux_sock_graft(struct sock *sk, struct socket *parent) | |
4844 | { | |
4845 | struct inode_security_struct *isec = | |
4846 | inode_security_novalidate(SOCK_INODE(parent)); | |
4847 | struct sk_security_struct *sksec = sk->sk_security; | |
4848 | ||
4849 | if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 || | |
4850 | sk->sk_family == PF_UNIX) | |
4851 | isec->sid = sksec->sid; | |
4852 | sksec->sclass = isec->sclass; | |
4853 | } | |
4854 | ||
4855 | static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, | |
4856 | struct request_sock *req) | |
4857 | { | |
4858 | struct sk_security_struct *sksec = sk->sk_security; | |
4859 | int err; | |
4860 | u16 family = req->rsk_ops->family; | |
4861 | u32 connsid; | |
4862 | u32 peersid; | |
4863 | ||
4864 | err = selinux_skb_peerlbl_sid(skb, family, &peersid); | |
4865 | if (err) | |
4866 | return err; | |
4867 | err = selinux_conn_sid(sksec->sid, peersid, &connsid); | |
4868 | if (err) | |
4869 | return err; | |
4870 | req->secid = connsid; | |
4871 | req->peer_secid = peersid; | |
4872 | ||
4873 | return selinux_netlbl_inet_conn_request(req, family); | |
4874 | } | |
4875 | ||
4876 | static void selinux_inet_csk_clone(struct sock *newsk, | |
4877 | const struct request_sock *req) | |
4878 | { | |
4879 | struct sk_security_struct *newsksec = newsk->sk_security; | |
4880 | ||
4881 | newsksec->sid = req->secid; | |
4882 | newsksec->peer_sid = req->peer_secid; | |
4883 | /* NOTE: Ideally, we should also get the isec->sid for the | |
4884 | new socket in sync, but we don't have the isec available yet. | |
4885 | So we will wait until sock_graft to do it, by which | |
4886 | time it will have been created and available. */ | |
4887 | ||
4888 | /* We don't need to take any sort of lock here as we are the only | |
4889 | * thread with access to newsksec */ | |
4890 | selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family); | |
4891 | } | |
4892 | ||
4893 | static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb) | |
4894 | { | |
4895 | u16 family = sk->sk_family; | |
4896 | struct sk_security_struct *sksec = sk->sk_security; | |
4897 | ||
4898 | /* handle mapped IPv4 packets arriving via IPv6 sockets */ | |
4899 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) | |
4900 | family = PF_INET; | |
4901 | ||
4902 | selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid); | |
4903 | } | |
4904 | ||
4905 | static int selinux_secmark_relabel_packet(u32 sid) | |
4906 | { | |
4907 | const struct task_security_struct *__tsec; | |
4908 | u32 tsid; | |
4909 | ||
4910 | __tsec = current_security(); | |
4911 | tsid = __tsec->sid; | |
4912 | ||
4913 | return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL); | |
4914 | } | |
4915 | ||
4916 | static void selinux_secmark_refcount_inc(void) | |
4917 | { | |
4918 | atomic_inc(&selinux_secmark_refcount); | |
4919 | } | |
4920 | ||
4921 | static void selinux_secmark_refcount_dec(void) | |
4922 | { | |
4923 | atomic_dec(&selinux_secmark_refcount); | |
4924 | } | |
4925 | ||
4926 | static void selinux_req_classify_flow(const struct request_sock *req, | |
4927 | struct flowi *fl) | |
4928 | { | |
4929 | fl->flowi_secid = req->secid; | |
4930 | } | |
4931 | ||
4932 | static int selinux_tun_dev_alloc_security(void **security) | |
4933 | { | |
4934 | struct tun_security_struct *tunsec; | |
4935 | ||
4936 | tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); | |
4937 | if (!tunsec) | |
4938 | return -ENOMEM; | |
4939 | tunsec->sid = current_sid(); | |
4940 | ||
4941 | *security = tunsec; | |
4942 | return 0; | |
4943 | } | |
4944 | ||
4945 | static void selinux_tun_dev_free_security(void *security) | |
4946 | { | |
4947 | kfree(security); | |
4948 | } | |
4949 | ||
4950 | static int selinux_tun_dev_create(void) | |
4951 | { | |
4952 | u32 sid = current_sid(); | |
4953 | ||
4954 | /* we aren't taking into account the "sockcreate" SID since the socket | |
4955 | * that is being created here is not a socket in the traditional sense, | |
4956 | * instead it is a private sock, accessible only to the kernel, and | |
4957 | * representing a wide range of network traffic spanning multiple | |
4958 | * connections unlike traditional sockets - check the TUN driver to | |
4959 | * get a better understanding of why this socket is special */ | |
4960 | ||
4961 | return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE, | |
4962 | NULL); | |
4963 | } | |
4964 | ||
4965 | static int selinux_tun_dev_attach_queue(void *security) | |
4966 | { | |
4967 | struct tun_security_struct *tunsec = security; | |
4968 | ||
4969 | return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, | |
4970 | TUN_SOCKET__ATTACH_QUEUE, NULL); | |
4971 | } | |
4972 | ||
4973 | static int selinux_tun_dev_attach(struct sock *sk, void *security) | |
4974 | { | |
4975 | struct tun_security_struct *tunsec = security; | |
4976 | struct sk_security_struct *sksec = sk->sk_security; | |
4977 | ||
4978 | /* we don't currently perform any NetLabel based labeling here and it | |
4979 | * isn't clear that we would want to do so anyway; while we could apply | |
4980 | * labeling without the support of the TUN user the resulting labeled | |
4981 | * traffic from the other end of the connection would almost certainly | |
4982 | * cause confusion to the TUN user that had no idea network labeling | |
4983 | * protocols were being used */ | |
4984 | ||
4985 | sksec->sid = tunsec->sid; | |
4986 | sksec->sclass = SECCLASS_TUN_SOCKET; | |
4987 | ||
4988 | return 0; | |
4989 | } | |
4990 | ||
4991 | static int selinux_tun_dev_open(void *security) | |
4992 | { | |
4993 | struct tun_security_struct *tunsec = security; | |
4994 | u32 sid = current_sid(); | |
4995 | int err; | |
4996 | ||
4997 | err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, | |
4998 | TUN_SOCKET__RELABELFROM, NULL); | |
4999 | if (err) | |
5000 | return err; | |
5001 | err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, | |
5002 | TUN_SOCKET__RELABELTO, NULL); | |
5003 | if (err) | |
5004 | return err; | |
5005 | tunsec->sid = sid; | |
5006 | ||
5007 | return 0; | |
5008 | } | |
5009 | ||
5010 | static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb) | |
5011 | { | |
5012 | int err = 0; | |
5013 | u32 perm; | |
5014 | struct nlmsghdr *nlh; | |
5015 | struct sk_security_struct *sksec = sk->sk_security; | |
5016 | ||
5017 | if (skb->len < NLMSG_HDRLEN) { | |
5018 | err = -EINVAL; | |
5019 | goto out; | |
5020 | } | |
5021 | nlh = nlmsg_hdr(skb); | |
5022 | ||
5023 | err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm); | |
5024 | if (err) { | |
5025 | if (err == -EINVAL) { | |
5026 | pr_warn_ratelimited("SELinux: unrecognized netlink" | |
5027 | " message: protocol=%hu nlmsg_type=%hu sclass=%s" | |
5028 | " pig=%d comm=%s\n", | |
5029 | sk->sk_protocol, nlh->nlmsg_type, | |
5030 | secclass_map[sksec->sclass - 1].name, | |
5031 | task_pid_nr(current), current->comm); | |
5032 | if (!selinux_enforcing || security_get_allow_unknown()) | |
5033 | err = 0; | |
5034 | } | |
5035 | ||
5036 | /* Ignore */ | |
5037 | if (err == -ENOENT) | |
5038 | err = 0; | |
5039 | goto out; | |
5040 | } | |
5041 | ||
5042 | err = sock_has_perm(sk, perm); | |
5043 | out: | |
5044 | return err; | |
5045 | } | |
5046 | ||
5047 | #ifdef CONFIG_NETFILTER | |
5048 | ||
5049 | static unsigned int selinux_ip_forward(struct sk_buff *skb, | |
5050 | const struct net_device *indev, | |
5051 | u16 family) | |
5052 | { | |
5053 | int err; | |
5054 | char *addrp; | |
5055 | u32 peer_sid; | |
5056 | struct common_audit_data ad; | |
5057 | struct lsm_network_audit net = {0,}; | |
5058 | u8 secmark_active; | |
5059 | u8 netlbl_active; | |
5060 | u8 peerlbl_active; | |
5061 | ||
5062 | if (!selinux_policycap_netpeer) | |
5063 | return NF_ACCEPT; | |
5064 | ||
5065 | secmark_active = selinux_secmark_enabled(); | |
5066 | netlbl_active = netlbl_enabled(); | |
5067 | peerlbl_active = selinux_peerlbl_enabled(); | |
5068 | if (!secmark_active && !peerlbl_active) | |
5069 | return NF_ACCEPT; | |
5070 | ||
5071 | if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0) | |
5072 | return NF_DROP; | |
5073 | ||
5074 | ad.type = LSM_AUDIT_DATA_NET; | |
5075 | ad.u.net = &net; | |
5076 | ad.u.net->netif = indev->ifindex; | |
5077 | ad.u.net->family = family; | |
5078 | if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0) | |
5079 | return NF_DROP; | |
5080 | ||
5081 | if (peerlbl_active) { | |
5082 | err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex, | |
5083 | addrp, family, peer_sid, &ad); | |
5084 | if (err) { | |
5085 | selinux_netlbl_err(skb, family, err, 1); | |
5086 | return NF_DROP; | |
5087 | } | |
5088 | } | |
5089 | ||
5090 | if (secmark_active) | |
5091 | if (avc_has_perm(peer_sid, skb->secmark, | |
5092 | SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) | |
5093 | return NF_DROP; | |
5094 | ||
5095 | if (netlbl_active) | |
5096 | /* we do this in the FORWARD path and not the POST_ROUTING | |
5097 | * path because we want to make sure we apply the necessary | |
5098 | * labeling before IPsec is applied so we can leverage AH | |
5099 | * protection */ | |
5100 | if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) | |
5101 | return NF_DROP; | |
5102 | ||
5103 | return NF_ACCEPT; | |
5104 | } | |
5105 | ||
5106 | static unsigned int selinux_ipv4_forward(void *priv, | |
5107 | struct sk_buff *skb, | |
5108 | const struct nf_hook_state *state) | |
5109 | { | |
5110 | return selinux_ip_forward(skb, state->in, PF_INET); | |
5111 | } | |
5112 | ||
5113 | #if IS_ENABLED(CONFIG_IPV6) | |
5114 | static unsigned int selinux_ipv6_forward(void *priv, | |
5115 | struct sk_buff *skb, | |
5116 | const struct nf_hook_state *state) | |
5117 | { | |
5118 | return selinux_ip_forward(skb, state->in, PF_INET6); | |
5119 | } | |
5120 | #endif /* IPV6 */ | |
5121 | ||
5122 | static unsigned int selinux_ip_output(struct sk_buff *skb, | |
5123 | u16 family) | |
5124 | { | |
5125 | struct sock *sk; | |
5126 | u32 sid; | |
5127 | ||
5128 | if (!netlbl_enabled()) | |
5129 | return NF_ACCEPT; | |
5130 | ||
5131 | /* we do this in the LOCAL_OUT path and not the POST_ROUTING path | |
5132 | * because we want to make sure we apply the necessary labeling | |
5133 | * before IPsec is applied so we can leverage AH protection */ | |
5134 | sk = skb->sk; | |
5135 | if (sk) { | |
5136 | struct sk_security_struct *sksec; | |
5137 | ||
5138 | if (sk_listener(sk)) | |
5139 | /* if the socket is the listening state then this | |
5140 | * packet is a SYN-ACK packet which means it needs to | |
5141 | * be labeled based on the connection/request_sock and | |
5142 | * not the parent socket. unfortunately, we can't | |
5143 | * lookup the request_sock yet as it isn't queued on | |
5144 | * the parent socket until after the SYN-ACK is sent. | |
5145 | * the "solution" is to simply pass the packet as-is | |
5146 | * as any IP option based labeling should be copied | |
5147 | * from the initial connection request (in the IP | |
5148 | * layer). it is far from ideal, but until we get a | |
5149 | * security label in the packet itself this is the | |
5150 | * best we can do. */ | |
5151 | return NF_ACCEPT; | |
5152 | ||
5153 | /* standard practice, label using the parent socket */ | |
5154 | sksec = sk->sk_security; | |
5155 | sid = sksec->sid; | |
5156 | } else | |
5157 | sid = SECINITSID_KERNEL; | |
5158 | if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) | |
5159 | return NF_DROP; | |
5160 | ||
5161 | return NF_ACCEPT; | |
5162 | } | |
5163 | ||
5164 | static unsigned int selinux_ipv4_output(void *priv, | |
5165 | struct sk_buff *skb, | |
5166 | const struct nf_hook_state *state) | |
5167 | { | |
5168 | return selinux_ip_output(skb, PF_INET); | |
5169 | } | |
5170 | ||
5171 | #if IS_ENABLED(CONFIG_IPV6) | |
5172 | static unsigned int selinux_ipv6_output(void *priv, | |
5173 | struct sk_buff *skb, | |
5174 | const struct nf_hook_state *state) | |
5175 | { | |
5176 | return selinux_ip_output(skb, PF_INET6); | |
5177 | } | |
5178 | #endif /* IPV6 */ | |
5179 | ||
5180 | static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb, | |
5181 | int ifindex, | |
5182 | u16 family) | |
5183 | { | |
5184 | struct sock *sk = skb_to_full_sk(skb); | |
5185 | struct sk_security_struct *sksec; | |
5186 | struct common_audit_data ad; | |
5187 | struct lsm_network_audit net = {0,}; | |
5188 | char *addrp; | |
5189 | u8 proto; | |
5190 | ||
5191 | if (sk == NULL) | |
5192 | return NF_ACCEPT; | |
5193 | sksec = sk->sk_security; | |
5194 | ||
5195 | ad.type = LSM_AUDIT_DATA_NET; | |
5196 | ad.u.net = &net; | |
5197 | ad.u.net->netif = ifindex; | |
5198 | ad.u.net->family = family; | |
5199 | if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto)) | |
5200 | return NF_DROP; | |
5201 | ||
5202 | if (selinux_secmark_enabled()) | |
5203 | if (avc_has_perm(sksec->sid, skb->secmark, | |
5204 | SECCLASS_PACKET, PACKET__SEND, &ad)) | |
5205 | return NF_DROP_ERR(-ECONNREFUSED); | |
5206 | ||
5207 | if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto)) | |
5208 | return NF_DROP_ERR(-ECONNREFUSED); | |
5209 | ||
5210 | return NF_ACCEPT; | |
5211 | } | |
5212 | ||
5213 | static unsigned int selinux_ip_postroute(struct sk_buff *skb, | |
5214 | const struct net_device *outdev, | |
5215 | u16 family) | |
5216 | { | |
5217 | u32 secmark_perm; | |
5218 | u32 peer_sid; | |
5219 | int ifindex = outdev->ifindex; | |
5220 | struct sock *sk; | |
5221 | struct common_audit_data ad; | |
5222 | struct lsm_network_audit net = {0,}; | |
5223 | char *addrp; | |
5224 | u8 secmark_active; | |
5225 | u8 peerlbl_active; | |
5226 | ||
5227 | /* If any sort of compatibility mode is enabled then handoff processing | |
5228 | * to the selinux_ip_postroute_compat() function to deal with the | |
5229 | * special handling. We do this in an attempt to keep this function | |
5230 | * as fast and as clean as possible. */ | |
5231 | if (!selinux_policycap_netpeer) | |
5232 | return selinux_ip_postroute_compat(skb, ifindex, family); | |
5233 | ||
5234 | secmark_active = selinux_secmark_enabled(); | |
5235 | peerlbl_active = selinux_peerlbl_enabled(); | |
5236 | if (!secmark_active && !peerlbl_active) | |
5237 | return NF_ACCEPT; | |
5238 | ||
5239 | sk = skb_to_full_sk(skb); | |
5240 | ||
5241 | #ifdef CONFIG_XFRM | |
5242 | /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec | |
5243 | * packet transformation so allow the packet to pass without any checks | |
5244 | * since we'll have another chance to perform access control checks | |
5245 | * when the packet is on it's final way out. | |
5246 | * NOTE: there appear to be some IPv6 multicast cases where skb->dst | |
5247 | * is NULL, in this case go ahead and apply access control. | |
5248 | * NOTE: if this is a local socket (skb->sk != NULL) that is in the | |
5249 | * TCP listening state we cannot wait until the XFRM processing | |
5250 | * is done as we will miss out on the SA label if we do; | |
5251 | * unfortunately, this means more work, but it is only once per | |
5252 | * connection. */ | |
5253 | if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL && | |
5254 | !(sk && sk_listener(sk))) | |
5255 | return NF_ACCEPT; | |
5256 | #endif | |
5257 | ||
5258 | if (sk == NULL) { | |
5259 | /* Without an associated socket the packet is either coming | |
5260 | * from the kernel or it is being forwarded; check the packet | |
5261 | * to determine which and if the packet is being forwarded | |
5262 | * query the packet directly to determine the security label. */ | |
5263 | if (skb->skb_iif) { | |
5264 | secmark_perm = PACKET__FORWARD_OUT; | |
5265 | if (selinux_skb_peerlbl_sid(skb, family, &peer_sid)) | |
5266 | return NF_DROP; | |
5267 | } else { | |
5268 | secmark_perm = PACKET__SEND; | |
5269 | peer_sid = SECINITSID_KERNEL; | |
5270 | } | |
5271 | } else if (sk_listener(sk)) { | |
5272 | /* Locally generated packet but the associated socket is in the | |
5273 | * listening state which means this is a SYN-ACK packet. In | |
5274 | * this particular case the correct security label is assigned | |
5275 | * to the connection/request_sock but unfortunately we can't | |
5276 | * query the request_sock as it isn't queued on the parent | |
5277 | * socket until after the SYN-ACK packet is sent; the only | |
5278 | * viable choice is to regenerate the label like we do in | |
5279 | * selinux_inet_conn_request(). See also selinux_ip_output() | |
5280 | * for similar problems. */ | |
5281 | u32 skb_sid; | |
5282 | struct sk_security_struct *sksec; | |
5283 | ||
5284 | sksec = sk->sk_security; | |
5285 | if (selinux_skb_peerlbl_sid(skb, family, &skb_sid)) | |
5286 | return NF_DROP; | |
5287 | /* At this point, if the returned skb peerlbl is SECSID_NULL | |
5288 | * and the packet has been through at least one XFRM | |
5289 | * transformation then we must be dealing with the "final" | |
5290 | * form of labeled IPsec packet; since we've already applied | |
5291 | * all of our access controls on this packet we can safely | |
5292 | * pass the packet. */ | |
5293 | if (skb_sid == SECSID_NULL) { | |
5294 | switch (family) { | |
5295 | case PF_INET: | |
5296 | if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) | |
5297 | return NF_ACCEPT; | |
5298 | break; | |
5299 | case PF_INET6: | |
5300 | if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) | |
5301 | return NF_ACCEPT; | |
5302 | break; | |
5303 | default: | |
5304 | return NF_DROP_ERR(-ECONNREFUSED); | |
5305 | } | |
5306 | } | |
5307 | if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid)) | |
5308 | return NF_DROP; | |
5309 | secmark_perm = PACKET__SEND; | |
5310 | } else { | |
5311 | /* Locally generated packet, fetch the security label from the | |
5312 | * associated socket. */ | |
5313 | struct sk_security_struct *sksec = sk->sk_security; | |
5314 | peer_sid = sksec->sid; | |
5315 | secmark_perm = PACKET__SEND; | |
5316 | } | |
5317 | ||
5318 | ad.type = LSM_AUDIT_DATA_NET; | |
5319 | ad.u.net = &net; | |
5320 | ad.u.net->netif = ifindex; | |
5321 | ad.u.net->family = family; | |
5322 | if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL)) | |
5323 | return NF_DROP; | |
5324 | ||
5325 | if (secmark_active) | |
5326 | if (avc_has_perm(peer_sid, skb->secmark, | |
5327 | SECCLASS_PACKET, secmark_perm, &ad)) | |
5328 | return NF_DROP_ERR(-ECONNREFUSED); | |
5329 | ||
5330 | if (peerlbl_active) { | |
5331 | u32 if_sid; | |
5332 | u32 node_sid; | |
5333 | ||
5334 | if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid)) | |
5335 | return NF_DROP; | |
5336 | if (avc_has_perm(peer_sid, if_sid, | |
5337 | SECCLASS_NETIF, NETIF__EGRESS, &ad)) | |
5338 | return NF_DROP_ERR(-ECONNREFUSED); | |
5339 | ||
5340 | if (sel_netnode_sid(addrp, family, &node_sid)) | |
5341 | return NF_DROP; | |
5342 | if (avc_has_perm(peer_sid, node_sid, | |
5343 | SECCLASS_NODE, NODE__SENDTO, &ad)) | |
5344 | return NF_DROP_ERR(-ECONNREFUSED); | |
5345 | } | |
5346 | ||
5347 | return NF_ACCEPT; | |
5348 | } | |
5349 | ||
5350 | static unsigned int selinux_ipv4_postroute(void *priv, | |
5351 | struct sk_buff *skb, | |
5352 | const struct nf_hook_state *state) | |
5353 | { | |
5354 | return selinux_ip_postroute(skb, state->out, PF_INET); | |
5355 | } | |
5356 | ||
5357 | #if IS_ENABLED(CONFIG_IPV6) | |
5358 | static unsigned int selinux_ipv6_postroute(void *priv, | |
5359 | struct sk_buff *skb, | |
5360 | const struct nf_hook_state *state) | |
5361 | { | |
5362 | return selinux_ip_postroute(skb, state->out, PF_INET6); | |
5363 | } | |
5364 | #endif /* IPV6 */ | |
5365 | ||
5366 | #endif /* CONFIG_NETFILTER */ | |
5367 | ||
5368 | static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) | |
5369 | { | |
5370 | return selinux_nlmsg_perm(sk, skb); | |
5371 | } | |
5372 | ||
5373 | static int ipc_alloc_security(struct kern_ipc_perm *perm, | |
5374 | u16 sclass) | |
5375 | { | |
5376 | struct ipc_security_struct *isec; | |
5377 | ||
5378 | isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL); | |
5379 | if (!isec) | |
5380 | return -ENOMEM; | |
5381 | ||
5382 | isec->sclass = sclass; | |
5383 | isec->sid = current_sid(); | |
5384 | perm->security = isec; | |
5385 | ||
5386 | return 0; | |
5387 | } | |
5388 | ||
5389 | static void ipc_free_security(struct kern_ipc_perm *perm) | |
5390 | { | |
5391 | struct ipc_security_struct *isec = perm->security; | |
5392 | perm->security = NULL; | |
5393 | kfree(isec); | |
5394 | } | |
5395 | ||
5396 | static int msg_msg_alloc_security(struct msg_msg *msg) | |
5397 | { | |
5398 | struct msg_security_struct *msec; | |
5399 | ||
5400 | msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL); | |
5401 | if (!msec) | |
5402 | return -ENOMEM; | |
5403 | ||
5404 | msec->sid = SECINITSID_UNLABELED; | |
5405 | msg->security = msec; | |
5406 | ||
5407 | return 0; | |
5408 | } | |
5409 | ||
5410 | static void msg_msg_free_security(struct msg_msg *msg) | |
5411 | { | |
5412 | struct msg_security_struct *msec = msg->security; | |
5413 | ||
5414 | msg->security = NULL; | |
5415 | kfree(msec); | |
5416 | } | |
5417 | ||
5418 | static int ipc_has_perm(struct kern_ipc_perm *ipc_perms, | |
5419 | u32 perms) | |
5420 | { | |
5421 | struct ipc_security_struct *isec; | |
5422 | struct common_audit_data ad; | |
5423 | u32 sid = current_sid(); | |
5424 | ||
5425 | isec = ipc_perms->security; | |
5426 | ||
5427 | ad.type = LSM_AUDIT_DATA_IPC; | |
5428 | ad.u.ipc_id = ipc_perms->key; | |
5429 | ||
5430 | return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad); | |
5431 | } | |
5432 | ||
5433 | static int selinux_msg_msg_alloc_security(struct msg_msg *msg) | |
5434 | { | |
5435 | return msg_msg_alloc_security(msg); | |
5436 | } | |
5437 | ||
5438 | static void selinux_msg_msg_free_security(struct msg_msg *msg) | |
5439 | { | |
5440 | msg_msg_free_security(msg); | |
5441 | } | |
5442 | ||
5443 | /* message queue security operations */ | |
5444 | static int selinux_msg_queue_alloc_security(struct msg_queue *msq) | |
5445 | { | |
5446 | struct ipc_security_struct *isec; | |
5447 | struct common_audit_data ad; | |
5448 | u32 sid = current_sid(); | |
5449 | int rc; | |
5450 | ||
5451 | rc = ipc_alloc_security(&msq->q_perm, SECCLASS_MSGQ); | |
5452 | if (rc) | |
5453 | return rc; | |
5454 | ||
5455 | isec = msq->q_perm.security; | |
5456 | ||
5457 | ad.type = LSM_AUDIT_DATA_IPC; | |
5458 | ad.u.ipc_id = msq->q_perm.key; | |
5459 | ||
5460 | rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, | |
5461 | MSGQ__CREATE, &ad); | |
5462 | if (rc) { | |
5463 | ipc_free_security(&msq->q_perm); | |
5464 | return rc; | |
5465 | } | |
5466 | return 0; | |
5467 | } | |
5468 | ||
5469 | static void selinux_msg_queue_free_security(struct msg_queue *msq) | |
5470 | { | |
5471 | ipc_free_security(&msq->q_perm); | |
5472 | } | |
5473 | ||
5474 | static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg) | |
5475 | { | |
5476 | struct ipc_security_struct *isec; | |
5477 | struct common_audit_data ad; | |
5478 | u32 sid = current_sid(); | |
5479 | ||
5480 | isec = msq->q_perm.security; | |
5481 | ||
5482 | ad.type = LSM_AUDIT_DATA_IPC; | |
5483 | ad.u.ipc_id = msq->q_perm.key; | |
5484 | ||
5485 | return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, | |
5486 | MSGQ__ASSOCIATE, &ad); | |
5487 | } | |
5488 | ||
5489 | static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd) | |
5490 | { | |
5491 | int err; | |
5492 | int perms; | |
5493 | ||
5494 | switch (cmd) { | |
5495 | case IPC_INFO: | |
5496 | case MSG_INFO: | |
5497 | /* No specific object, just general system-wide information. */ | |
5498 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
5499 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); | |
5500 | case IPC_STAT: | |
5501 | case MSG_STAT: | |
5502 | perms = MSGQ__GETATTR | MSGQ__ASSOCIATE; | |
5503 | break; | |
5504 | case IPC_SET: | |
5505 | perms = MSGQ__SETATTR; | |
5506 | break; | |
5507 | case IPC_RMID: | |
5508 | perms = MSGQ__DESTROY; | |
5509 | break; | |
5510 | default: | |
5511 | return 0; | |
5512 | } | |
5513 | ||
5514 | err = ipc_has_perm(&msq->q_perm, perms); | |
5515 | return err; | |
5516 | } | |
5517 | ||
5518 | static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) | |
5519 | { | |
5520 | struct ipc_security_struct *isec; | |
5521 | struct msg_security_struct *msec; | |
5522 | struct common_audit_data ad; | |
5523 | u32 sid = current_sid(); | |
5524 | int rc; | |
5525 | ||
5526 | isec = msq->q_perm.security; | |
5527 | msec = msg->security; | |
5528 | ||
5529 | /* | |
5530 | * First time through, need to assign label to the message | |
5531 | */ | |
5532 | if (msec->sid == SECINITSID_UNLABELED) { | |
5533 | /* | |
5534 | * Compute new sid based on current process and | |
5535 | * message queue this message will be stored in | |
5536 | */ | |
5537 | rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG, | |
5538 | NULL, &msec->sid); | |
5539 | if (rc) | |
5540 | return rc; | |
5541 | } | |
5542 | ||
5543 | ad.type = LSM_AUDIT_DATA_IPC; | |
5544 | ad.u.ipc_id = msq->q_perm.key; | |
5545 | ||
5546 | /* Can this process write to the queue? */ | |
5547 | rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ, | |
5548 | MSGQ__WRITE, &ad); | |
5549 | if (!rc) | |
5550 | /* Can this process send the message */ | |
5551 | rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG, | |
5552 | MSG__SEND, &ad); | |
5553 | if (!rc) | |
5554 | /* Can the message be put in the queue? */ | |
5555 | rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ, | |
5556 | MSGQ__ENQUEUE, &ad); | |
5557 | ||
5558 | return rc; | |
5559 | } | |
5560 | ||
5561 | static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, | |
5562 | struct task_struct *target, | |
5563 | long type, int mode) | |
5564 | { | |
5565 | struct ipc_security_struct *isec; | |
5566 | struct msg_security_struct *msec; | |
5567 | struct common_audit_data ad; | |
5568 | u32 sid = task_sid(target); | |
5569 | int rc; | |
5570 | ||
5571 | isec = msq->q_perm.security; | |
5572 | msec = msg->security; | |
5573 | ||
5574 | ad.type = LSM_AUDIT_DATA_IPC; | |
5575 | ad.u.ipc_id = msq->q_perm.key; | |
5576 | ||
5577 | rc = avc_has_perm(sid, isec->sid, | |
5578 | SECCLASS_MSGQ, MSGQ__READ, &ad); | |
5579 | if (!rc) | |
5580 | rc = avc_has_perm(sid, msec->sid, | |
5581 | SECCLASS_MSG, MSG__RECEIVE, &ad); | |
5582 | return rc; | |
5583 | } | |
5584 | ||
5585 | /* Shared Memory security operations */ | |
5586 | static int selinux_shm_alloc_security(struct shmid_kernel *shp) | |
5587 | { | |
5588 | struct ipc_security_struct *isec; | |
5589 | struct common_audit_data ad; | |
5590 | u32 sid = current_sid(); | |
5591 | int rc; | |
5592 | ||
5593 | rc = ipc_alloc_security(&shp->shm_perm, SECCLASS_SHM); | |
5594 | if (rc) | |
5595 | return rc; | |
5596 | ||
5597 | isec = shp->shm_perm.security; | |
5598 | ||
5599 | ad.type = LSM_AUDIT_DATA_IPC; | |
5600 | ad.u.ipc_id = shp->shm_perm.key; | |
5601 | ||
5602 | rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM, | |
5603 | SHM__CREATE, &ad); | |
5604 | if (rc) { | |
5605 | ipc_free_security(&shp->shm_perm); | |
5606 | return rc; | |
5607 | } | |
5608 | return 0; | |
5609 | } | |
5610 | ||
5611 | static void selinux_shm_free_security(struct shmid_kernel *shp) | |
5612 | { | |
5613 | ipc_free_security(&shp->shm_perm); | |
5614 | } | |
5615 | ||
5616 | static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg) | |
5617 | { | |
5618 | struct ipc_security_struct *isec; | |
5619 | struct common_audit_data ad; | |
5620 | u32 sid = current_sid(); | |
5621 | ||
5622 | isec = shp->shm_perm.security; | |
5623 | ||
5624 | ad.type = LSM_AUDIT_DATA_IPC; | |
5625 | ad.u.ipc_id = shp->shm_perm.key; | |
5626 | ||
5627 | return avc_has_perm(sid, isec->sid, SECCLASS_SHM, | |
5628 | SHM__ASSOCIATE, &ad); | |
5629 | } | |
5630 | ||
5631 | /* Note, at this point, shp is locked down */ | |
5632 | static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd) | |
5633 | { | |
5634 | int perms; | |
5635 | int err; | |
5636 | ||
5637 | switch (cmd) { | |
5638 | case IPC_INFO: | |
5639 | case SHM_INFO: | |
5640 | /* No specific object, just general system-wide information. */ | |
5641 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
5642 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); | |
5643 | case IPC_STAT: | |
5644 | case SHM_STAT: | |
5645 | perms = SHM__GETATTR | SHM__ASSOCIATE; | |
5646 | break; | |
5647 | case IPC_SET: | |
5648 | perms = SHM__SETATTR; | |
5649 | break; | |
5650 | case SHM_LOCK: | |
5651 | case SHM_UNLOCK: | |
5652 | perms = SHM__LOCK; | |
5653 | break; | |
5654 | case IPC_RMID: | |
5655 | perms = SHM__DESTROY; | |
5656 | break; | |
5657 | default: | |
5658 | return 0; | |
5659 | } | |
5660 | ||
5661 | err = ipc_has_perm(&shp->shm_perm, perms); | |
5662 | return err; | |
5663 | } | |
5664 | ||
5665 | static int selinux_shm_shmat(struct shmid_kernel *shp, | |
5666 | char __user *shmaddr, int shmflg) | |
5667 | { | |
5668 | u32 perms; | |
5669 | ||
5670 | if (shmflg & SHM_RDONLY) | |
5671 | perms = SHM__READ; | |
5672 | else | |
5673 | perms = SHM__READ | SHM__WRITE; | |
5674 | ||
5675 | return ipc_has_perm(&shp->shm_perm, perms); | |
5676 | } | |
5677 | ||
5678 | /* Semaphore security operations */ | |
5679 | static int selinux_sem_alloc_security(struct sem_array *sma) | |
5680 | { | |
5681 | struct ipc_security_struct *isec; | |
5682 | struct common_audit_data ad; | |
5683 | u32 sid = current_sid(); | |
5684 | int rc; | |
5685 | ||
5686 | rc = ipc_alloc_security(&sma->sem_perm, SECCLASS_SEM); | |
5687 | if (rc) | |
5688 | return rc; | |
5689 | ||
5690 | isec = sma->sem_perm.security; | |
5691 | ||
5692 | ad.type = LSM_AUDIT_DATA_IPC; | |
5693 | ad.u.ipc_id = sma->sem_perm.key; | |
5694 | ||
5695 | rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM, | |
5696 | SEM__CREATE, &ad); | |
5697 | if (rc) { | |
5698 | ipc_free_security(&sma->sem_perm); | |
5699 | return rc; | |
5700 | } | |
5701 | return 0; | |
5702 | } | |
5703 | ||
5704 | static void selinux_sem_free_security(struct sem_array *sma) | |
5705 | { | |
5706 | ipc_free_security(&sma->sem_perm); | |
5707 | } | |
5708 | ||
5709 | static int selinux_sem_associate(struct sem_array *sma, int semflg) | |
5710 | { | |
5711 | struct ipc_security_struct *isec; | |
5712 | struct common_audit_data ad; | |
5713 | u32 sid = current_sid(); | |
5714 | ||
5715 | isec = sma->sem_perm.security; | |
5716 | ||
5717 | ad.type = LSM_AUDIT_DATA_IPC; | |
5718 | ad.u.ipc_id = sma->sem_perm.key; | |
5719 | ||
5720 | return avc_has_perm(sid, isec->sid, SECCLASS_SEM, | |
5721 | SEM__ASSOCIATE, &ad); | |
5722 | } | |
5723 | ||
5724 | /* Note, at this point, sma is locked down */ | |
5725 | static int selinux_sem_semctl(struct sem_array *sma, int cmd) | |
5726 | { | |
5727 | int err; | |
5728 | u32 perms; | |
5729 | ||
5730 | switch (cmd) { | |
5731 | case IPC_INFO: | |
5732 | case SEM_INFO: | |
5733 | /* No specific object, just general system-wide information. */ | |
5734 | return avc_has_perm(current_sid(), SECINITSID_KERNEL, | |
5735 | SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL); | |
5736 | case GETPID: | |
5737 | case GETNCNT: | |
5738 | case GETZCNT: | |
5739 | perms = SEM__GETATTR; | |
5740 | break; | |
5741 | case GETVAL: | |
5742 | case GETALL: | |
5743 | perms = SEM__READ; | |
5744 | break; | |
5745 | case SETVAL: | |
5746 | case SETALL: | |
5747 | perms = SEM__WRITE; | |
5748 | break; | |
5749 | case IPC_RMID: | |
5750 | perms = SEM__DESTROY; | |
5751 | break; | |
5752 | case IPC_SET: | |
5753 | perms = SEM__SETATTR; | |
5754 | break; | |
5755 | case IPC_STAT: | |
5756 | case SEM_STAT: | |
5757 | perms = SEM__GETATTR | SEM__ASSOCIATE; | |
5758 | break; | |
5759 | default: | |
5760 | return 0; | |
5761 | } | |
5762 | ||
5763 | err = ipc_has_perm(&sma->sem_perm, perms); | |
5764 | return err; | |
5765 | } | |
5766 | ||
5767 | static int selinux_sem_semop(struct sem_array *sma, | |
5768 | struct sembuf *sops, unsigned nsops, int alter) | |
5769 | { | |
5770 | u32 perms; | |
5771 | ||
5772 | if (alter) | |
5773 | perms = SEM__READ | SEM__WRITE; | |
5774 | else | |
5775 | perms = SEM__READ; | |
5776 | ||
5777 | return ipc_has_perm(&sma->sem_perm, perms); | |
5778 | } | |
5779 | ||
5780 | static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag) | |
5781 | { | |
5782 | u32 av = 0; | |
5783 | ||
5784 | av = 0; | |
5785 | if (flag & S_IRUGO) | |
5786 | av |= IPC__UNIX_READ; | |
5787 | if (flag & S_IWUGO) | |
5788 | av |= IPC__UNIX_WRITE; | |
5789 | ||
5790 | if (av == 0) | |
5791 | return 0; | |
5792 | ||
5793 | return ipc_has_perm(ipcp, av); | |
5794 | } | |
5795 | ||
5796 | static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) | |
5797 | { | |
5798 | struct ipc_security_struct *isec = ipcp->security; | |
5799 | *secid = isec->sid; | |
5800 | } | |
5801 | ||
5802 | static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode) | |
5803 | { | |
5804 | if (inode) | |
5805 | inode_doinit_with_dentry(inode, dentry); | |
5806 | } | |
5807 | ||
5808 | static int selinux_getprocattr(struct task_struct *p, | |
5809 | char *name, char **value) | |
5810 | { | |
5811 | const struct task_security_struct *__tsec; | |
5812 | u32 sid; | |
5813 | int error; | |
5814 | unsigned len; | |
5815 | ||
5816 | rcu_read_lock(); | |
5817 | __tsec = __task_cred(p)->security; | |
5818 | ||
5819 | if (current != p) { | |
5820 | error = avc_has_perm(current_sid(), __tsec->sid, | |
5821 | SECCLASS_PROCESS, PROCESS__GETATTR, NULL); | |
5822 | if (error) | |
5823 | goto bad; | |
5824 | } | |
5825 | ||
5826 | if (!strcmp(name, "current")) | |
5827 | sid = __tsec->sid; | |
5828 | else if (!strcmp(name, "prev")) | |
5829 | sid = __tsec->osid; | |
5830 | else if (!strcmp(name, "exec")) | |
5831 | sid = __tsec->exec_sid; | |
5832 | else if (!strcmp(name, "fscreate")) | |
5833 | sid = __tsec->create_sid; | |
5834 | else if (!strcmp(name, "keycreate")) | |
5835 | sid = __tsec->keycreate_sid; | |
5836 | else if (!strcmp(name, "sockcreate")) | |
5837 | sid = __tsec->sockcreate_sid; | |
5838 | else { | |
5839 | error = -EINVAL; | |
5840 | goto bad; | |
5841 | } | |
5842 | rcu_read_unlock(); | |
5843 | ||
5844 | if (!sid) | |
5845 | return 0; | |
5846 | ||
5847 | error = security_sid_to_context(sid, value, &len); | |
5848 | if (error) | |
5849 | return error; | |
5850 | return len; | |
5851 | ||
5852 | bad: | |
5853 | rcu_read_unlock(); | |
5854 | return error; | |
5855 | } | |
5856 | ||
5857 | static int selinux_setprocattr(const char *name, void *value, size_t size) | |
5858 | { | |
5859 | struct task_security_struct *tsec; | |
5860 | struct cred *new; | |
5861 | u32 mysid = current_sid(), sid = 0, ptsid; | |
5862 | int error; | |
5863 | char *str = value; | |
5864 | ||
5865 | /* | |
5866 | * Basic control over ability to set these attributes at all. | |
5867 | */ | |
5868 | if (!strcmp(name, "exec")) | |
5869 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, | |
5870 | PROCESS__SETEXEC, NULL); | |
5871 | else if (!strcmp(name, "fscreate")) | |
5872 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, | |
5873 | PROCESS__SETFSCREATE, NULL); | |
5874 | else if (!strcmp(name, "keycreate")) | |
5875 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, | |
5876 | PROCESS__SETKEYCREATE, NULL); | |
5877 | else if (!strcmp(name, "sockcreate")) | |
5878 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, | |
5879 | PROCESS__SETSOCKCREATE, NULL); | |
5880 | else if (!strcmp(name, "current")) | |
5881 | error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS, | |
5882 | PROCESS__SETCURRENT, NULL); | |
5883 | else | |
5884 | error = -EINVAL; | |
5885 | if (error) | |
5886 | return error; | |
5887 | ||
5888 | /* Obtain a SID for the context, if one was specified. */ | |
5889 | if (size && str[0] && str[0] != '\n') { | |
5890 | if (str[size-1] == '\n') { | |
5891 | str[size-1] = 0; | |
5892 | size--; | |
5893 | } | |
5894 | error = security_context_to_sid(value, size, &sid, GFP_KERNEL); | |
5895 | if (error == -EINVAL && !strcmp(name, "fscreate")) { | |
5896 | if (!capable(CAP_MAC_ADMIN)) { | |
5897 | struct audit_buffer *ab; | |
5898 | size_t audit_size; | |
5899 | ||
5900 | /* We strip a nul only if it is at the end, otherwise the | |
5901 | * context contains a nul and we should audit that */ | |
5902 | if (str[size - 1] == '\0') | |
5903 | audit_size = size - 1; | |
5904 | else | |
5905 | audit_size = size; | |
5906 | ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR); | |
5907 | audit_log_format(ab, "op=fscreate invalid_context="); | |
5908 | audit_log_n_untrustedstring(ab, value, audit_size); | |
5909 | audit_log_end(ab); | |
5910 | ||
5911 | return error; | |
5912 | } | |
5913 | error = security_context_to_sid_force(value, size, | |
5914 | &sid); | |
5915 | } | |
5916 | if (error) | |
5917 | return error; | |
5918 | } | |
5919 | ||
5920 | new = prepare_creds(); | |
5921 | if (!new) | |
5922 | return -ENOMEM; | |
5923 | ||
5924 | /* Permission checking based on the specified context is | |
5925 | performed during the actual operation (execve, | |
5926 | open/mkdir/...), when we know the full context of the | |
5927 | operation. See selinux_bprm_set_creds for the execve | |
5928 | checks and may_create for the file creation checks. The | |
5929 | operation will then fail if the context is not permitted. */ | |
5930 | tsec = new->security; | |
5931 | if (!strcmp(name, "exec")) { | |
5932 | tsec->exec_sid = sid; | |
5933 | } else if (!strcmp(name, "fscreate")) { | |
5934 | tsec->create_sid = sid; | |
5935 | } else if (!strcmp(name, "keycreate")) { | |
5936 | error = avc_has_perm(mysid, sid, SECCLASS_KEY, KEY__CREATE, | |
5937 | NULL); | |
5938 | if (error) | |
5939 | goto abort_change; | |
5940 | tsec->keycreate_sid = sid; | |
5941 | } else if (!strcmp(name, "sockcreate")) { | |
5942 | tsec->sockcreate_sid = sid; | |
5943 | } else if (!strcmp(name, "current")) { | |
5944 | error = -EINVAL; | |
5945 | if (sid == 0) | |
5946 | goto abort_change; | |
5947 | ||
5948 | /* Only allow single threaded processes to change context */ | |
5949 | error = -EPERM; | |
5950 | if (!current_is_single_threaded()) { | |
5951 | error = security_bounded_transition(tsec->sid, sid); | |
5952 | if (error) | |
5953 | goto abort_change; | |
5954 | } | |
5955 | ||
5956 | /* Check permissions for the transition. */ | |
5957 | error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS, | |
5958 | PROCESS__DYNTRANSITION, NULL); | |
5959 | if (error) | |
5960 | goto abort_change; | |
5961 | ||
5962 | /* Check for ptracing, and update the task SID if ok. | |
5963 | Otherwise, leave SID unchanged and fail. */ | |
5964 | ptsid = ptrace_parent_sid(); | |
5965 | if (ptsid != 0) { | |
5966 | error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS, | |
5967 | PROCESS__PTRACE, NULL); | |
5968 | if (error) | |
5969 | goto abort_change; | |
5970 | } | |
5971 | ||
5972 | tsec->sid = sid; | |
5973 | } else { | |
5974 | error = -EINVAL; | |
5975 | goto abort_change; | |
5976 | } | |
5977 | ||
5978 | commit_creds(new); | |
5979 | return size; | |
5980 | ||
5981 | abort_change: | |
5982 | abort_creds(new); | |
5983 | return error; | |
5984 | } | |
5985 | ||
5986 | static int selinux_ismaclabel(const char *name) | |
5987 | { | |
5988 | return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); | |
5989 | } | |
5990 | ||
5991 | static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) | |
5992 | { | |
5993 | return security_sid_to_context(secid, secdata, seclen); | |
5994 | } | |
5995 | ||
5996 | static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) | |
5997 | { | |
5998 | return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); | |
5999 | } | |
6000 | ||
6001 | static void selinux_release_secctx(char *secdata, u32 seclen) | |
6002 | { | |
6003 | kfree(secdata); | |
6004 | } | |
6005 | ||
6006 | static void selinux_inode_invalidate_secctx(struct inode *inode) | |
6007 | { | |
6008 | struct inode_security_struct *isec = inode->i_security; | |
6009 | ||
6010 | spin_lock(&isec->lock); | |
6011 | isec->initialized = LABEL_INVALID; | |
6012 | spin_unlock(&isec->lock); | |
6013 | } | |
6014 | ||
6015 | /* | |
6016 | * called with inode->i_mutex locked | |
6017 | */ | |
6018 | static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) | |
6019 | { | |
6020 | return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0); | |
6021 | } | |
6022 | ||
6023 | /* | |
6024 | * called with inode->i_mutex locked | |
6025 | */ | |
6026 | static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) | |
6027 | { | |
6028 | return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0); | |
6029 | } | |
6030 | ||
6031 | static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) | |
6032 | { | |
6033 | int len = 0; | |
6034 | len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX, | |
6035 | ctx, true); | |
6036 | if (len < 0) | |
6037 | return len; | |
6038 | *ctxlen = len; | |
6039 | return 0; | |
6040 | } | |
6041 | #ifdef CONFIG_KEYS | |
6042 | ||
6043 | static int selinux_key_alloc(struct key *k, const struct cred *cred, | |
6044 | unsigned long flags) | |
6045 | { | |
6046 | const struct task_security_struct *tsec; | |
6047 | struct key_security_struct *ksec; | |
6048 | ||
6049 | ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); | |
6050 | if (!ksec) | |
6051 | return -ENOMEM; | |
6052 | ||
6053 | tsec = cred->security; | |
6054 | if (tsec->keycreate_sid) | |
6055 | ksec->sid = tsec->keycreate_sid; | |
6056 | else | |
6057 | ksec->sid = tsec->sid; | |
6058 | ||
6059 | k->security = ksec; | |
6060 | return 0; | |
6061 | } | |
6062 | ||
6063 | static void selinux_key_free(struct key *k) | |
6064 | { | |
6065 | struct key_security_struct *ksec = k->security; | |
6066 | ||
6067 | k->security = NULL; | |
6068 | kfree(ksec); | |
6069 | } | |
6070 | ||
6071 | static int selinux_key_permission(key_ref_t key_ref, | |
6072 | const struct cred *cred, | |
6073 | unsigned perm) | |
6074 | { | |
6075 | struct key *key; | |
6076 | struct key_security_struct *ksec; | |
6077 | u32 sid; | |
6078 | ||
6079 | /* if no specific permissions are requested, we skip the | |
6080 | permission check. No serious, additional covert channels | |
6081 | appear to be created. */ | |
6082 | if (perm == 0) | |
6083 | return 0; | |
6084 | ||
6085 | sid = cred_sid(cred); | |
6086 | ||
6087 | key = key_ref_to_ptr(key_ref); | |
6088 | ksec = key->security; | |
6089 | ||
6090 | return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL); | |
6091 | } | |
6092 | ||
6093 | static int selinux_key_getsecurity(struct key *key, char **_buffer) | |
6094 | { | |
6095 | struct key_security_struct *ksec = key->security; | |
6096 | char *context = NULL; | |
6097 | unsigned len; | |
6098 | int rc; | |
6099 | ||
6100 | rc = security_sid_to_context(ksec->sid, &context, &len); | |
6101 | if (!rc) | |
6102 | rc = len; | |
6103 | *_buffer = context; | |
6104 | return rc; | |
6105 | } | |
6106 | ||
6107 | #endif | |
6108 | ||
6109 | static struct security_hook_list selinux_hooks[] = { | |
6110 | LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), | |
6111 | LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), | |
6112 | LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder), | |
6113 | LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file), | |
6114 | ||
6115 | LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check), | |
6116 | LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme), | |
6117 | LSM_HOOK_INIT(capget, selinux_capget), | |
6118 | LSM_HOOK_INIT(capset, selinux_capset), | |
6119 | LSM_HOOK_INIT(capable, selinux_capable), | |
6120 | LSM_HOOK_INIT(quotactl, selinux_quotactl), | |
6121 | LSM_HOOK_INIT(quota_on, selinux_quota_on), | |
6122 | LSM_HOOK_INIT(syslog, selinux_syslog), | |
6123 | LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory), | |
6124 | ||
6125 | LSM_HOOK_INIT(netlink_send, selinux_netlink_send), | |
6126 | ||
6127 | LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds), | |
6128 | LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds), | |
6129 | LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds), | |
6130 | LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec), | |
6131 | ||
6132 | LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security), | |
6133 | LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security), | |
6134 | LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data), | |
6135 | LSM_HOOK_INIT(sb_remount, selinux_sb_remount), | |
6136 | LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount), | |
6137 | LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options), | |
6138 | LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs), | |
6139 | LSM_HOOK_INIT(sb_mount, selinux_mount), | |
6140 | LSM_HOOK_INIT(sb_umount, selinux_umount), | |
6141 | LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts), | |
6142 | LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts), | |
6143 | LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str), | |
6144 | ||
6145 | LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security), | |
6146 | LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as), | |
6147 | ||
6148 | LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), | |
6149 | LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), | |
6150 | LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), | |
6151 | LSM_HOOK_INIT(inode_create, selinux_inode_create), | |
6152 | LSM_HOOK_INIT(inode_link, selinux_inode_link), | |
6153 | LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), | |
6154 | LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink), | |
6155 | LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir), | |
6156 | LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir), | |
6157 | LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod), | |
6158 | LSM_HOOK_INIT(inode_rename, selinux_inode_rename), | |
6159 | LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink), | |
6160 | LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link), | |
6161 | LSM_HOOK_INIT(inode_permission, selinux_inode_permission), | |
6162 | LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr), | |
6163 | LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr), | |
6164 | LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr), | |
6165 | LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr), | |
6166 | LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr), | |
6167 | LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr), | |
6168 | LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr), | |
6169 | LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity), | |
6170 | LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity), | |
6171 | LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity), | |
6172 | LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid), | |
6173 | LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up), | |
6174 | LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr), | |
6175 | ||
6176 | LSM_HOOK_INIT(file_permission, selinux_file_permission), | |
6177 | LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security), | |
6178 | LSM_HOOK_INIT(file_free_security, selinux_file_free_security), | |
6179 | LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl), | |
6180 | LSM_HOOK_INIT(mmap_file, selinux_mmap_file), | |
6181 | LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr), | |
6182 | LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect), | |
6183 | LSM_HOOK_INIT(file_lock, selinux_file_lock), | |
6184 | LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl), | |
6185 | LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner), | |
6186 | LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask), | |
6187 | LSM_HOOK_INIT(file_receive, selinux_file_receive), | |
6188 | ||
6189 | LSM_HOOK_INIT(file_open, selinux_file_open), | |
6190 | ||
6191 | LSM_HOOK_INIT(task_create, selinux_task_create), | |
6192 | LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank), | |
6193 | LSM_HOOK_INIT(cred_free, selinux_cred_free), | |
6194 | LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare), | |
6195 | LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer), | |
6196 | LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), | |
6197 | LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), | |
6198 | LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), | |
6199 | LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), | |
6200 | LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), | |
6201 | LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), | |
6202 | LSM_HOOK_INIT(task_getsid, selinux_task_getsid), | |
6203 | LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid), | |
6204 | LSM_HOOK_INIT(task_setnice, selinux_task_setnice), | |
6205 | LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), | |
6206 | LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio), | |
6207 | LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit), | |
6208 | LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler), | |
6209 | LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler), | |
6210 | LSM_HOOK_INIT(task_movememory, selinux_task_movememory), | |
6211 | LSM_HOOK_INIT(task_kill, selinux_task_kill), | |
6212 | LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode), | |
6213 | ||
6214 | LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission), | |
6215 | LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid), | |
6216 | ||
6217 | LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security), | |
6218 | LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security), | |
6219 | ||
6220 | LSM_HOOK_INIT(msg_queue_alloc_security, | |
6221 | selinux_msg_queue_alloc_security), | |
6222 | LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security), | |
6223 | LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate), | |
6224 | LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl), | |
6225 | LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd), | |
6226 | LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv), | |
6227 | ||
6228 | LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security), | |
6229 | LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security), | |
6230 | LSM_HOOK_INIT(shm_associate, selinux_shm_associate), | |
6231 | LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl), | |
6232 | LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat), | |
6233 | ||
6234 | LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security), | |
6235 | LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security), | |
6236 | LSM_HOOK_INIT(sem_associate, selinux_sem_associate), | |
6237 | LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl), | |
6238 | LSM_HOOK_INIT(sem_semop, selinux_sem_semop), | |
6239 | ||
6240 | LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate), | |
6241 | ||
6242 | LSM_HOOK_INIT(getprocattr, selinux_getprocattr), | |
6243 | LSM_HOOK_INIT(setprocattr, selinux_setprocattr), | |
6244 | ||
6245 | LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel), | |
6246 | LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx), | |
6247 | LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid), | |
6248 | LSM_HOOK_INIT(release_secctx, selinux_release_secctx), | |
6249 | LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx), | |
6250 | LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx), | |
6251 | LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx), | |
6252 | LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx), | |
6253 | ||
6254 | LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect), | |
6255 | LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send), | |
6256 | ||
6257 | LSM_HOOK_INIT(socket_create, selinux_socket_create), | |
6258 | LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create), | |
6259 | LSM_HOOK_INIT(socket_bind, selinux_socket_bind), | |
6260 | LSM_HOOK_INIT(socket_connect, selinux_socket_connect), | |
6261 | LSM_HOOK_INIT(socket_listen, selinux_socket_listen), | |
6262 | LSM_HOOK_INIT(socket_accept, selinux_socket_accept), | |
6263 | LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg), | |
6264 | LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg), | |
6265 | LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname), | |
6266 | LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername), | |
6267 | LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt), | |
6268 | LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt), | |
6269 | LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown), | |
6270 | LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb), | |
6271 | LSM_HOOK_INIT(socket_getpeersec_stream, | |
6272 | selinux_socket_getpeersec_stream), | |
6273 | LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram), | |
6274 | LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security), | |
6275 | LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security), | |
6276 | LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security), | |
6277 | LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid), | |
6278 | LSM_HOOK_INIT(sock_graft, selinux_sock_graft), | |
6279 | LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request), | |
6280 | LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone), | |
6281 | LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established), | |
6282 | LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet), | |
6283 | LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc), | |
6284 | LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec), | |
6285 | LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow), | |
6286 | LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security), | |
6287 | LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security), | |
6288 | LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create), | |
6289 | LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue), | |
6290 | LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach), | |
6291 | LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open), | |
6292 | ||
6293 | #ifdef CONFIG_SECURITY_NETWORK_XFRM | |
6294 | LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc), | |
6295 | LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone), | |
6296 | LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free), | |
6297 | LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete), | |
6298 | LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc), | |
6299 | LSM_HOOK_INIT(xfrm_state_alloc_acquire, | |
6300 | selinux_xfrm_state_alloc_acquire), | |
6301 | LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free), | |
6302 | LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete), | |
6303 | LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup), | |
6304 | LSM_HOOK_INIT(xfrm_state_pol_flow_match, | |
6305 | selinux_xfrm_state_pol_flow_match), | |
6306 | LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session), | |
6307 | #endif | |
6308 | ||
6309 | #ifdef CONFIG_KEYS | |
6310 | LSM_HOOK_INIT(key_alloc, selinux_key_alloc), | |
6311 | LSM_HOOK_INIT(key_free, selinux_key_free), | |
6312 | LSM_HOOK_INIT(key_permission, selinux_key_permission), | |
6313 | LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), | |
6314 | #endif | |
6315 | ||
6316 | #ifdef CONFIG_AUDIT | |
6317 | LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init), | |
6318 | LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known), | |
6319 | LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match), | |
6320 | LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free), | |
6321 | #endif | |
6322 | }; | |
6323 | ||
6324 | static __init int selinux_init(void) | |
6325 | { | |
6326 | if (!security_module_enable("selinux")) { | |
6327 | selinux_enabled = 0; | |
6328 | return 0; | |
6329 | } | |
6330 | ||
6331 | if (!selinux_enabled) { | |
6332 | printk(KERN_INFO "SELinux: Disabled at boot.\n"); | |
6333 | return 0; | |
6334 | } | |
6335 | ||
6336 | printk(KERN_INFO "SELinux: Initializing.\n"); | |
6337 | ||
6338 | /* Set the security state for the initial task. */ | |
6339 | cred_init_security(); | |
6340 | ||
6341 | default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC); | |
6342 | ||
6343 | sel_inode_cache = kmem_cache_create("selinux_inode_security", | |
6344 | sizeof(struct inode_security_struct), | |
6345 | 0, SLAB_PANIC, NULL); | |
6346 | file_security_cache = kmem_cache_create("selinux_file_security", | |
6347 | sizeof(struct file_security_struct), | |
6348 | 0, SLAB_PANIC, NULL); | |
6349 | avc_init(); | |
6350 | ||
6351 | security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux"); | |
6352 | ||
6353 | if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET)) | |
6354 | panic("SELinux: Unable to register AVC netcache callback\n"); | |
6355 | ||
6356 | if (selinux_enforcing) | |
6357 | printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n"); | |
6358 | else | |
6359 | printk(KERN_DEBUG "SELinux: Starting in permissive mode\n"); | |
6360 | ||
6361 | return 0; | |
6362 | } | |
6363 | ||
6364 | static void delayed_superblock_init(struct super_block *sb, void *unused) | |
6365 | { | |
6366 | superblock_doinit(sb, NULL); | |
6367 | } | |
6368 | ||
6369 | void selinux_complete_init(void) | |
6370 | { | |
6371 | printk(KERN_DEBUG "SELinux: Completing initialization.\n"); | |
6372 | ||
6373 | /* Set up any superblocks initialized prior to the policy load. */ | |
6374 | printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n"); | |
6375 | iterate_supers(delayed_superblock_init, NULL); | |
6376 | } | |
6377 | ||
6378 | /* SELinux requires early initialization in order to label | |
6379 | all processes and objects when they are created. */ | |
6380 | security_initcall(selinux_init); | |
6381 | ||
6382 | #if defined(CONFIG_NETFILTER) | |
6383 | ||
6384 | static struct nf_hook_ops selinux_nf_ops[] = { | |
6385 | { | |
6386 | .hook = selinux_ipv4_postroute, | |
6387 | .pf = NFPROTO_IPV4, | |
6388 | .hooknum = NF_INET_POST_ROUTING, | |
6389 | .priority = NF_IP_PRI_SELINUX_LAST, | |
6390 | }, | |
6391 | { | |
6392 | .hook = selinux_ipv4_forward, | |
6393 | .pf = NFPROTO_IPV4, | |
6394 | .hooknum = NF_INET_FORWARD, | |
6395 | .priority = NF_IP_PRI_SELINUX_FIRST, | |
6396 | }, | |
6397 | { | |
6398 | .hook = selinux_ipv4_output, | |
6399 | .pf = NFPROTO_IPV4, | |
6400 | .hooknum = NF_INET_LOCAL_OUT, | |
6401 | .priority = NF_IP_PRI_SELINUX_FIRST, | |
6402 | }, | |
6403 | #if IS_ENABLED(CONFIG_IPV6) | |
6404 | { | |
6405 | .hook = selinux_ipv6_postroute, | |
6406 | .pf = NFPROTO_IPV6, | |
6407 | .hooknum = NF_INET_POST_ROUTING, | |
6408 | .priority = NF_IP6_PRI_SELINUX_LAST, | |
6409 | }, | |
6410 | { | |
6411 | .hook = selinux_ipv6_forward, | |
6412 | .pf = NFPROTO_IPV6, | |
6413 | .hooknum = NF_INET_FORWARD, | |
6414 | .priority = NF_IP6_PRI_SELINUX_FIRST, | |
6415 | }, | |
6416 | { | |
6417 | .hook = selinux_ipv6_output, | |
6418 | .pf = NFPROTO_IPV6, | |
6419 | .hooknum = NF_INET_LOCAL_OUT, | |
6420 | .priority = NF_IP6_PRI_SELINUX_FIRST, | |
6421 | }, | |
6422 | #endif /* IPV6 */ | |
6423 | }; | |
6424 | ||
6425 | static int __init selinux_nf_ip_init(void) | |
6426 | { | |
6427 | int err; | |
6428 | ||
6429 | if (!selinux_enabled) | |
6430 | return 0; | |
6431 | ||
6432 | printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n"); | |
6433 | ||
6434 | err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); | |
6435 | if (err) | |
6436 | panic("SELinux: nf_register_hooks: error %d\n", err); | |
6437 | ||
6438 | return 0; | |
6439 | } | |
6440 | ||
6441 | __initcall(selinux_nf_ip_init); | |
6442 | ||
6443 | #ifdef CONFIG_SECURITY_SELINUX_DISABLE | |
6444 | static void selinux_nf_ip_exit(void) | |
6445 | { | |
6446 | printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n"); | |
6447 | ||
6448 | nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops)); | |
6449 | } | |
6450 | #endif | |
6451 | ||
6452 | #else /* CONFIG_NETFILTER */ | |
6453 | ||
6454 | #ifdef CONFIG_SECURITY_SELINUX_DISABLE | |
6455 | #define selinux_nf_ip_exit() | |
6456 | #endif | |
6457 | ||
6458 | #endif /* CONFIG_NETFILTER */ | |
6459 | ||
6460 | #ifdef CONFIG_SECURITY_SELINUX_DISABLE | |
6461 | static int selinux_disabled; | |
6462 | ||
6463 | int selinux_disable(void) | |
6464 | { | |
6465 | if (ss_initialized) { | |
6466 | /* Not permitted after initial policy load. */ | |
6467 | return -EINVAL; | |
6468 | } | |
6469 | ||
6470 | if (selinux_disabled) { | |
6471 | /* Only do this once. */ | |
6472 | return -EINVAL; | |
6473 | } | |
6474 | ||
6475 | printk(KERN_INFO "SELinux: Disabled at runtime.\n"); | |
6476 | ||
6477 | selinux_disabled = 1; | |
6478 | selinux_enabled = 0; | |
6479 | ||
6480 | security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks)); | |
6481 | ||
6482 | /* Try to destroy the avc node cache */ | |
6483 | avc_disable(); | |
6484 | ||
6485 | /* Unregister netfilter hooks. */ | |
6486 | selinux_nf_ip_exit(); | |
6487 | ||
6488 | /* Unregister selinuxfs. */ | |
6489 | exit_sel_fs(); | |
6490 | ||
6491 | return 0; | |
6492 | } | |
6493 | #endif |