]> bbs.cooldavid.org Git - net-next-2.6.git/blame - security/smack/smack_lsm.c
lsm: Remove the socket_post_accept() hook
[net-next-2.6.git] / security / smack / smack_lsm.c
CommitLineData
e114e473
CS
1/*
2 * Simplified MAC Kernel (smack) security module
3 *
4 * This file contains the smack hook function implementations.
5 *
6 * Author:
7 * Casey Schaufler <casey@schaufler-ca.com>
8 *
9 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2,
13 * as published by the Free Software Foundation.
14 */
15
16#include <linux/xattr.h>
17#include <linux/pagemap.h>
18#include <linux/mount.h>
19#include <linux/stat.h>
20#include <linux/ext2_fs.h>
21#include <linux/kd.h>
22#include <asm/ioctls.h>
23#include <linux/tcp.h>
24#include <linux/udp.h>
25#include <linux/mutex.h>
26#include <linux/pipe_fs_i.h>
27#include <net/netlabel.h>
28#include <net/cipso_ipv4.h>
d20bdda6 29#include <linux/audit.h>
e114e473
CS
30
31#include "smack.h"
32
c69e8d9c
DH
33#define task_security(task) (task_cred_xxx((task), security))
34
e114e473
CS
35/*
36 * I hope these are the hokeyist lines of code in the module. Casey.
37 */
38#define DEVPTS_SUPER_MAGIC 0x1cd1
39#define SOCKFS_MAGIC 0x534F434B
40#define TMPFS_MAGIC 0x01021994
41
42/**
43 * smk_fetch - Fetch the smack label from a file.
44 * @ip: a pointer to the inode
45 * @dp: a pointer to the dentry
46 *
47 * Returns a pointer to the master list entry for the Smack label
48 * or NULL if there was no label to fetch.
49 */
50static char *smk_fetch(struct inode *ip, struct dentry *dp)
51{
52 int rc;
53 char in[SMK_LABELLEN];
54
55 if (ip->i_op->getxattr == NULL)
56 return NULL;
57
58 rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN);
59 if (rc < 0)
60 return NULL;
61
62 return smk_import(in, rc);
63}
64
65/**
66 * new_inode_smack - allocate an inode security blob
67 * @smack: a pointer to the Smack label to use in the blob
68 *
69 * Returns the new blob or NULL if there's no memory available
70 */
71struct inode_smack *new_inode_smack(char *smack)
72{
73 struct inode_smack *isp;
74
75 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
76 if (isp == NULL)
77 return NULL;
78
79 isp->smk_inode = smack;
80 isp->smk_flags = 0;
81 mutex_init(&isp->smk_lock);
82
83 return isp;
84}
85
86/*
87 * LSM hooks.
88 * We he, that is fun!
89 */
90
91/**
5cd9c58f 92 * smack_ptrace_may_access - Smack approval on PTRACE_ATTACH
e114e473 93 * @ctp: child task pointer
251a2a95 94 * @mode: ptrace attachment mode
e114e473
CS
95 *
96 * Returns 0 if access is OK, an error code otherwise
97 *
98 * Do the capability checks, and require read and write.
99 */
5cd9c58f 100static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode)
e114e473
CS
101{
102 int rc;
103
5cd9c58f 104 rc = cap_ptrace_may_access(ctp, mode);
e114e473
CS
105 if (rc != 0)
106 return rc;
107
d84f4f99 108 rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE);
5cd9c58f 109 if (rc != 0 && capable(CAP_MAC_OVERRIDE))
e114e473 110 return 0;
5cd9c58f
DH
111 return rc;
112}
113
114/**
115 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
116 * @ptp: parent task pointer
117 *
118 * Returns 0 if access is OK, an error code otherwise
119 *
120 * Do the capability checks, and require read and write.
121 */
122static int smack_ptrace_traceme(struct task_struct *ptp)
123{
124 int rc;
125
126 rc = cap_ptrace_traceme(ptp);
127 if (rc != 0)
128 return rc;
e114e473 129
d84f4f99 130 rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE);
5cd9c58f
DH
131 if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE))
132 return 0;
e114e473
CS
133 return rc;
134}
135
136/**
137 * smack_syslog - Smack approval on syslog
138 * @type: message type
139 *
140 * Require that the task has the floor label
141 *
142 * Returns 0 on success, error code otherwise.
143 */
144static int smack_syslog(int type)
145{
146 int rc;
86a264ab 147 char *sp = current_security();
e114e473
CS
148
149 rc = cap_syslog(type);
150 if (rc != 0)
151 return rc;
152
153 if (capable(CAP_MAC_OVERRIDE))
154 return 0;
155
156 if (sp != smack_known_floor.smk_known)
157 rc = -EACCES;
158
159 return rc;
160}
161
162
163/*
164 * Superblock Hooks.
165 */
166
167/**
168 * smack_sb_alloc_security - allocate a superblock blob
169 * @sb: the superblock getting the blob
170 *
171 * Returns 0 on success or -ENOMEM on error.
172 */
173static int smack_sb_alloc_security(struct super_block *sb)
174{
175 struct superblock_smack *sbsp;
176
177 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
178
179 if (sbsp == NULL)
180 return -ENOMEM;
181
182 sbsp->smk_root = smack_known_floor.smk_known;
183 sbsp->smk_default = smack_known_floor.smk_known;
184 sbsp->smk_floor = smack_known_floor.smk_known;
185 sbsp->smk_hat = smack_known_hat.smk_known;
186 sbsp->smk_initialized = 0;
187 spin_lock_init(&sbsp->smk_sblock);
188
189 sb->s_security = sbsp;
190
191 return 0;
192}
193
194/**
195 * smack_sb_free_security - free a superblock blob
196 * @sb: the superblock getting the blob
197 *
198 */
199static void smack_sb_free_security(struct super_block *sb)
200{
201 kfree(sb->s_security);
202 sb->s_security = NULL;
203}
204
205/**
206 * smack_sb_copy_data - copy mount options data for processing
e114e473 207 * @orig: where to start
251a2a95 208 * @smackopts: mount options string
e114e473
CS
209 *
210 * Returns 0 on success or -ENOMEM on error.
211 *
212 * Copy the Smack specific mount options out of the mount
213 * options list.
214 */
e0007529 215static int smack_sb_copy_data(char *orig, char *smackopts)
e114e473
CS
216{
217 char *cp, *commap, *otheropts, *dp;
218
e114e473
CS
219 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
220 if (otheropts == NULL)
221 return -ENOMEM;
222
223 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
224 if (strstr(cp, SMK_FSDEFAULT) == cp)
225 dp = smackopts;
226 else if (strstr(cp, SMK_FSFLOOR) == cp)
227 dp = smackopts;
228 else if (strstr(cp, SMK_FSHAT) == cp)
229 dp = smackopts;
230 else if (strstr(cp, SMK_FSROOT) == cp)
231 dp = smackopts;
232 else
233 dp = otheropts;
234
235 commap = strchr(cp, ',');
236 if (commap != NULL)
237 *commap = '\0';
238
239 if (*dp != '\0')
240 strcat(dp, ",");
241 strcat(dp, cp);
242 }
243
244 strcpy(orig, otheropts);
245 free_page((unsigned long)otheropts);
246
247 return 0;
248}
249
250/**
251 * smack_sb_kern_mount - Smack specific mount processing
252 * @sb: the file system superblock
12204e24 253 * @flags: the mount flags
e114e473
CS
254 * @data: the smack mount options
255 *
256 * Returns 0 on success, an error code on failure
257 */
12204e24 258static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
e114e473
CS
259{
260 struct dentry *root = sb->s_root;
261 struct inode *inode = root->d_inode;
262 struct superblock_smack *sp = sb->s_security;
263 struct inode_smack *isp;
264 char *op;
265 char *commap;
266 char *nsp;
267
268 spin_lock(&sp->smk_sblock);
269 if (sp->smk_initialized != 0) {
270 spin_unlock(&sp->smk_sblock);
271 return 0;
272 }
273 sp->smk_initialized = 1;
274 spin_unlock(&sp->smk_sblock);
275
276 for (op = data; op != NULL; op = commap) {
277 commap = strchr(op, ',');
278 if (commap != NULL)
279 *commap++ = '\0';
280
281 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
282 op += strlen(SMK_FSHAT);
283 nsp = smk_import(op, 0);
284 if (nsp != NULL)
285 sp->smk_hat = nsp;
286 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
287 op += strlen(SMK_FSFLOOR);
288 nsp = smk_import(op, 0);
289 if (nsp != NULL)
290 sp->smk_floor = nsp;
291 } else if (strncmp(op, SMK_FSDEFAULT,
292 strlen(SMK_FSDEFAULT)) == 0) {
293 op += strlen(SMK_FSDEFAULT);
294 nsp = smk_import(op, 0);
295 if (nsp != NULL)
296 sp->smk_default = nsp;
297 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
298 op += strlen(SMK_FSROOT);
299 nsp = smk_import(op, 0);
300 if (nsp != NULL)
301 sp->smk_root = nsp;
302 }
303 }
304
305 /*
306 * Initialize the root inode.
307 */
308 isp = inode->i_security;
309 if (isp == NULL)
310 inode->i_security = new_inode_smack(sp->smk_root);
311 else
312 isp->smk_inode = sp->smk_root;
313
314 return 0;
315}
316
317/**
318 * smack_sb_statfs - Smack check on statfs
319 * @dentry: identifies the file system in question
320 *
321 * Returns 0 if current can read the floor of the filesystem,
322 * and error code otherwise
323 */
324static int smack_sb_statfs(struct dentry *dentry)
325{
326 struct superblock_smack *sbp = dentry->d_sb->s_security;
327
328 return smk_curacc(sbp->smk_floor, MAY_READ);
329}
330
331/**
332 * smack_sb_mount - Smack check for mounting
333 * @dev_name: unused
251a2a95 334 * @path: mount point
e114e473
CS
335 * @type: unused
336 * @flags: unused
337 * @data: unused
338 *
339 * Returns 0 if current can write the floor of the filesystem
340 * being mounted on, an error code otherwise.
341 */
b5266eb4 342static int smack_sb_mount(char *dev_name, struct path *path,
e114e473
CS
343 char *type, unsigned long flags, void *data)
344{
b5266eb4 345 struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
e114e473
CS
346
347 return smk_curacc(sbp->smk_floor, MAY_WRITE);
348}
349
350/**
351 * smack_sb_umount - Smack check for unmounting
352 * @mnt: file system to unmount
353 * @flags: unused
354 *
355 * Returns 0 if current can write the floor of the filesystem
356 * being unmounted, an error code otherwise.
357 */
358static int smack_sb_umount(struct vfsmount *mnt, int flags)
359{
360 struct superblock_smack *sbp;
361
362 sbp = mnt->mnt_sb->s_security;
363
364 return smk_curacc(sbp->smk_floor, MAY_WRITE);
365}
366
367/*
368 * Inode hooks
369 */
370
371/**
372 * smack_inode_alloc_security - allocate an inode blob
251a2a95 373 * @inode: the inode in need of a blob
e114e473
CS
374 *
375 * Returns 0 if it gets a blob, -ENOMEM otherwise
376 */
377static int smack_inode_alloc_security(struct inode *inode)
378{
86a264ab 379 inode->i_security = new_inode_smack(current_security());
e114e473
CS
380 if (inode->i_security == NULL)
381 return -ENOMEM;
382 return 0;
383}
384
385/**
386 * smack_inode_free_security - free an inode blob
251a2a95 387 * @inode: the inode with a blob
e114e473
CS
388 *
389 * Clears the blob pointer in inode
390 */
391static void smack_inode_free_security(struct inode *inode)
392{
393 kfree(inode->i_security);
394 inode->i_security = NULL;
395}
396
397/**
398 * smack_inode_init_security - copy out the smack from an inode
399 * @inode: the inode
400 * @dir: unused
401 * @name: where to put the attribute name
402 * @value: where to put the attribute value
403 * @len: where to put the length of the attribute
404 *
405 * Returns 0 if it all works out, -ENOMEM if there's no memory
406 */
407static int smack_inode_init_security(struct inode *inode, struct inode *dir,
408 char **name, void **value, size_t *len)
409{
410 char *isp = smk_of_inode(inode);
411
412 if (name) {
413 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
414 if (*name == NULL)
415 return -ENOMEM;
416 }
417
418 if (value) {
419 *value = kstrdup(isp, GFP_KERNEL);
420 if (*value == NULL)
421 return -ENOMEM;
422 }
423
424 if (len)
425 *len = strlen(isp) + 1;
426
427 return 0;
428}
429
430/**
431 * smack_inode_link - Smack check on link
432 * @old_dentry: the existing object
433 * @dir: unused
434 * @new_dentry: the new object
435 *
436 * Returns 0 if access is permitted, an error code otherwise
437 */
438static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
439 struct dentry *new_dentry)
440{
441 int rc;
442 char *isp;
443
444 isp = smk_of_inode(old_dentry->d_inode);
445 rc = smk_curacc(isp, MAY_WRITE);
446
447 if (rc == 0 && new_dentry->d_inode != NULL) {
448 isp = smk_of_inode(new_dentry->d_inode);
449 rc = smk_curacc(isp, MAY_WRITE);
450 }
451
452 return rc;
453}
454
455/**
456 * smack_inode_unlink - Smack check on inode deletion
457 * @dir: containing directory object
458 * @dentry: file to unlink
459 *
460 * Returns 0 if current can write the containing directory
461 * and the object, error code otherwise
462 */
463static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
464{
465 struct inode *ip = dentry->d_inode;
466 int rc;
467
468 /*
469 * You need write access to the thing you're unlinking
470 */
471 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE);
472 if (rc == 0)
473 /*
474 * You also need write access to the containing directory
475 */
476 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
477
478 return rc;
479}
480
481/**
482 * smack_inode_rmdir - Smack check on directory deletion
483 * @dir: containing directory object
484 * @dentry: directory to unlink
485 *
486 * Returns 0 if current can write the containing directory
487 * and the directory, error code otherwise
488 */
489static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
490{
491 int rc;
492
493 /*
494 * You need write access to the thing you're removing
495 */
496 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
497 if (rc == 0)
498 /*
499 * You also need write access to the containing directory
500 */
501 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
502
503 return rc;
504}
505
506/**
507 * smack_inode_rename - Smack check on rename
508 * @old_inode: the old directory
509 * @old_dentry: unused
510 * @new_inode: the new directory
511 * @new_dentry: unused
512 *
513 * Read and write access is required on both the old and
514 * new directories.
515 *
516 * Returns 0 if access is permitted, an error code otherwise
517 */
518static int smack_inode_rename(struct inode *old_inode,
519 struct dentry *old_dentry,
520 struct inode *new_inode,
521 struct dentry *new_dentry)
522{
523 int rc;
524 char *isp;
525
526 isp = smk_of_inode(old_dentry->d_inode);
527 rc = smk_curacc(isp, MAY_READWRITE);
528
529 if (rc == 0 && new_dentry->d_inode != NULL) {
530 isp = smk_of_inode(new_dentry->d_inode);
531 rc = smk_curacc(isp, MAY_READWRITE);
532 }
533
534 return rc;
535}
536
537/**
538 * smack_inode_permission - Smack version of permission()
539 * @inode: the inode in question
540 * @mask: the access requested
e114e473
CS
541 *
542 * This is the important Smack hook.
543 *
544 * Returns 0 if access is permitted, -EACCES otherwise
545 */
b77b0646 546static int smack_inode_permission(struct inode *inode, int mask)
e114e473
CS
547{
548 /*
549 * No permission to check. Existence test. Yup, it's there.
550 */
551 if (mask == 0)
552 return 0;
553
554 return smk_curacc(smk_of_inode(inode), mask);
555}
556
557/**
558 * smack_inode_setattr - Smack check for setting attributes
559 * @dentry: the object
560 * @iattr: for the force flag
561 *
562 * Returns 0 if access is permitted, an error code otherwise
563 */
564static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
565{
566 /*
567 * Need to allow for clearing the setuid bit.
568 */
569 if (iattr->ia_valid & ATTR_FORCE)
570 return 0;
571
572 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
573}
574
575/**
576 * smack_inode_getattr - Smack check for getting attributes
577 * @mnt: unused
578 * @dentry: the object
579 *
580 * Returns 0 if access is permitted, an error code otherwise
581 */
582static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
583{
584 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
585}
586
587/**
588 * smack_inode_setxattr - Smack check for setting xattrs
589 * @dentry: the object
590 * @name: name of the attribute
591 * @value: unused
592 * @size: unused
593 * @flags: unused
594 *
595 * This protects the Smack attribute explicitly.
596 *
597 * Returns 0 if access is permitted, an error code otherwise
598 */
8f0cfa52
DH
599static int smack_inode_setxattr(struct dentry *dentry, const char *name,
600 const void *value, size_t size, int flags)
e114e473 601{
bcdca225 602 int rc = 0;
e114e473 603
bcdca225
CS
604 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
605 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
606 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
607 if (!capable(CAP_MAC_ADMIN))
608 rc = -EPERM;
609 } else
610 rc = cap_inode_setxattr(dentry, name, value, size, flags);
611
612 if (rc == 0)
613 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
614
615 return rc;
e114e473
CS
616}
617
618/**
619 * smack_inode_post_setxattr - Apply the Smack update approved above
620 * @dentry: object
621 * @name: attribute name
622 * @value: attribute value
623 * @size: attribute size
624 * @flags: unused
625 *
626 * Set the pointer in the inode blob to the entry found
627 * in the master label list.
628 */
8f0cfa52
DH
629static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
630 const void *value, size_t size, int flags)
e114e473
CS
631{
632 struct inode_smack *isp;
633 char *nsp;
634
635 /*
636 * Not SMACK
637 */
638 if (strcmp(name, XATTR_NAME_SMACK))
639 return;
640
641 if (size >= SMK_LABELLEN)
642 return;
643
644 isp = dentry->d_inode->i_security;
645
646 /*
647 * No locking is done here. This is a pointer
648 * assignment.
649 */
650 nsp = smk_import(value, size);
651 if (nsp != NULL)
652 isp->smk_inode = nsp;
653 else
654 isp->smk_inode = smack_known_invalid.smk_known;
655
656 return;
657}
658
659/*
660 * smack_inode_getxattr - Smack check on getxattr
661 * @dentry: the object
662 * @name: unused
663 *
664 * Returns 0 if access is permitted, an error code otherwise
665 */
8f0cfa52 666static int smack_inode_getxattr(struct dentry *dentry, const char *name)
e114e473
CS
667{
668 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
669}
670
671/*
672 * smack_inode_removexattr - Smack check on removexattr
673 * @dentry: the object
674 * @name: name of the attribute
675 *
676 * Removing the Smack attribute requires CAP_MAC_ADMIN
677 *
678 * Returns 0 if access is permitted, an error code otherwise
679 */
8f0cfa52 680static int smack_inode_removexattr(struct dentry *dentry, const char *name)
e114e473 681{
bcdca225 682 int rc = 0;
e114e473 683
bcdca225
CS
684 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
685 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
686 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
687 if (!capable(CAP_MAC_ADMIN))
688 rc = -EPERM;
689 } else
690 rc = cap_inode_removexattr(dentry, name);
691
692 if (rc == 0)
693 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
694
695 return rc;
e114e473
CS
696}
697
698/**
699 * smack_inode_getsecurity - get smack xattrs
700 * @inode: the object
701 * @name: attribute name
702 * @buffer: where to put the result
251a2a95 703 * @alloc: unused
e114e473
CS
704 *
705 * Returns the size of the attribute or an error code
706 */
707static int smack_inode_getsecurity(const struct inode *inode,
708 const char *name, void **buffer,
709 bool alloc)
710{
711 struct socket_smack *ssp;
712 struct socket *sock;
713 struct super_block *sbp;
714 struct inode *ip = (struct inode *)inode;
715 char *isp;
716 int ilen;
717 int rc = 0;
718
719 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
720 isp = smk_of_inode(inode);
721 ilen = strlen(isp) + 1;
722 *buffer = isp;
723 return ilen;
724 }
725
726 /*
727 * The rest of the Smack xattrs are only on sockets.
728 */
729 sbp = ip->i_sb;
730 if (sbp->s_magic != SOCKFS_MAGIC)
731 return -EOPNOTSUPP;
732
733 sock = SOCKET_I(ip);
2e1d146a 734 if (sock == NULL || sock->sk == NULL)
e114e473
CS
735 return -EOPNOTSUPP;
736
737 ssp = sock->sk->sk_security;
738
739 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
740 isp = ssp->smk_in;
741 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
742 isp = ssp->smk_out;
743 else
744 return -EOPNOTSUPP;
745
746 ilen = strlen(isp) + 1;
747 if (rc == 0) {
748 *buffer = isp;
749 rc = ilen;
750 }
751
752 return rc;
753}
754
755
756/**
757 * smack_inode_listsecurity - list the Smack attributes
758 * @inode: the object
759 * @buffer: where they go
760 * @buffer_size: size of buffer
761 *
762 * Returns 0 on success, -EINVAL otherwise
763 */
764static int smack_inode_listsecurity(struct inode *inode, char *buffer,
765 size_t buffer_size)
766{
767 int len = strlen(XATTR_NAME_SMACK);
768
769 if (buffer != NULL && len <= buffer_size) {
770 memcpy(buffer, XATTR_NAME_SMACK, len);
771 return len;
772 }
773 return -EINVAL;
774}
775
d20bdda6
AD
776/**
777 * smack_inode_getsecid - Extract inode's security id
778 * @inode: inode to extract the info from
779 * @secid: where result will be saved
780 */
781static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
782{
783 struct inode_smack *isp = inode->i_security;
784
785 *secid = smack_to_secid(isp->smk_inode);
786}
787
e114e473
CS
788/*
789 * File Hooks
790 */
791
792/**
793 * smack_file_permission - Smack check on file operations
794 * @file: unused
795 * @mask: unused
796 *
797 * Returns 0
798 *
799 * Should access checks be done on each read or write?
800 * UNICOS and SELinux say yes.
801 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
802 *
803 * I'll say no for now. Smack does not do the frequent
804 * label changing that SELinux does.
805 */
806static int smack_file_permission(struct file *file, int mask)
807{
808 return 0;
809}
810
811/**
812 * smack_file_alloc_security - assign a file security blob
813 * @file: the object
814 *
815 * The security blob for a file is a pointer to the master
816 * label list, so no allocation is done.
817 *
818 * Returns 0
819 */
820static int smack_file_alloc_security(struct file *file)
821{
86a264ab 822 file->f_security = current_security();
e114e473
CS
823 return 0;
824}
825
826/**
827 * smack_file_free_security - clear a file security blob
828 * @file: the object
829 *
830 * The security blob for a file is a pointer to the master
831 * label list, so no memory is freed.
832 */
833static void smack_file_free_security(struct file *file)
834{
835 file->f_security = NULL;
836}
837
838/**
839 * smack_file_ioctl - Smack check on ioctls
840 * @file: the object
841 * @cmd: what to do
842 * @arg: unused
843 *
844 * Relies heavily on the correct use of the ioctl command conventions.
845 *
846 * Returns 0 if allowed, error code otherwise
847 */
848static int smack_file_ioctl(struct file *file, unsigned int cmd,
849 unsigned long arg)
850{
851 int rc = 0;
852
853 if (_IOC_DIR(cmd) & _IOC_WRITE)
854 rc = smk_curacc(file->f_security, MAY_WRITE);
855
856 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
857 rc = smk_curacc(file->f_security, MAY_READ);
858
859 return rc;
860}
861
862/**
863 * smack_file_lock - Smack check on file locking
864 * @file: the object
251a2a95 865 * @cmd: unused
e114e473
CS
866 *
867 * Returns 0 if current has write access, error code otherwise
868 */
869static int smack_file_lock(struct file *file, unsigned int cmd)
870{
871 return smk_curacc(file->f_security, MAY_WRITE);
872}
873
874/**
875 * smack_file_fcntl - Smack check on fcntl
876 * @file: the object
877 * @cmd: what action to check
878 * @arg: unused
879 *
880 * Returns 0 if current has access, error code otherwise
881 */
882static int smack_file_fcntl(struct file *file, unsigned int cmd,
883 unsigned long arg)
884{
885 int rc;
886
887 switch (cmd) {
888 case F_DUPFD:
889 case F_GETFD:
890 case F_GETFL:
891 case F_GETLK:
892 case F_GETOWN:
893 case F_GETSIG:
894 rc = smk_curacc(file->f_security, MAY_READ);
895 break;
896 case F_SETFD:
897 case F_SETFL:
898 case F_SETLK:
899 case F_SETLKW:
900 case F_SETOWN:
901 case F_SETSIG:
902 rc = smk_curacc(file->f_security, MAY_WRITE);
903 break;
904 default:
905 rc = smk_curacc(file->f_security, MAY_READWRITE);
906 }
907
908 return rc;
909}
910
911/**
912 * smack_file_set_fowner - set the file security blob value
913 * @file: object in question
914 *
915 * Returns 0
916 * Further research may be required on this one.
917 */
918static int smack_file_set_fowner(struct file *file)
919{
86a264ab 920 file->f_security = current_security();
e114e473
CS
921 return 0;
922}
923
924/**
925 * smack_file_send_sigiotask - Smack on sigio
926 * @tsk: The target task
927 * @fown: the object the signal come from
928 * @signum: unused
929 *
930 * Allow a privileged task to get signals even if it shouldn't
931 *
932 * Returns 0 if a subject with the object's smack could
933 * write to the task, an error code otherwise.
934 */
935static int smack_file_send_sigiotask(struct task_struct *tsk,
936 struct fown_struct *fown, int signum)
937{
938 struct file *file;
939 int rc;
940
941 /*
942 * struct fown_struct is never outside the context of a struct file
943 */
944 file = container_of(fown, struct file, f_owner);
b6dff3ec 945 rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE);
5cd9c58f 946 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
e114e473
CS
947 return 0;
948 return rc;
949}
950
951/**
952 * smack_file_receive - Smack file receive check
953 * @file: the object
954 *
955 * Returns 0 if current has access, error code otherwise
956 */
957static int smack_file_receive(struct file *file)
958{
959 int may = 0;
960
961 /*
962 * This code relies on bitmasks.
963 */
964 if (file->f_mode & FMODE_READ)
965 may = MAY_READ;
966 if (file->f_mode & FMODE_WRITE)
967 may |= MAY_WRITE;
968
969 return smk_curacc(file->f_security, may);
970}
971
972/*
973 * Task hooks
974 */
975
e114e473 976/**
f1752eec
DH
977 * smack_cred_free - "free" task-level security credentials
978 * @cred: the credentials in question
e114e473
CS
979 *
980 * Smack isn't using copies of blobs. Everyone
981 * points to an immutable list. The blobs never go away.
982 * There is no leak here.
983 */
f1752eec 984static void smack_cred_free(struct cred *cred)
e114e473 985{
f1752eec 986 cred->security = NULL;
e114e473
CS
987}
988
d84f4f99
DH
989/**
990 * smack_cred_prepare - prepare new set of credentials for modification
991 * @new: the new credentials
992 * @old: the original credentials
993 * @gfp: the atomicity of any memory allocations
994 *
995 * Prepare a new set of credentials for modification.
996 */
997static int smack_cred_prepare(struct cred *new, const struct cred *old,
998 gfp_t gfp)
999{
1000 new->security = old->security;
1001 return 0;
1002}
1003
251a2a95
RD
1004/**
1005 * smack_cred_commit - commit new credentials
d84f4f99
DH
1006 * @new: the new credentials
1007 * @old: the original credentials
1008 */
1009static void smack_cred_commit(struct cred *new, const struct cred *old)
1010{
1011}
1012
3a3b7ce9
DH
1013/**
1014 * smack_kernel_act_as - Set the subjective context in a set of credentials
251a2a95
RD
1015 * @new: points to the set of credentials to be modified.
1016 * @secid: specifies the security ID to be set
3a3b7ce9
DH
1017 *
1018 * Set the security data for a kernel service.
1019 */
1020static int smack_kernel_act_as(struct cred *new, u32 secid)
1021{
1022 char *smack = smack_from_secid(secid);
1023
1024 if (smack == NULL)
1025 return -EINVAL;
1026
1027 new->security = smack;
1028 return 0;
1029}
1030
1031/**
1032 * smack_kernel_create_files_as - Set the file creation label in a set of creds
251a2a95
RD
1033 * @new: points to the set of credentials to be modified
1034 * @inode: points to the inode to use as a reference
3a3b7ce9
DH
1035 *
1036 * Set the file creation context in a set of credentials to the same
1037 * as the objective context of the specified inode
1038 */
1039static int smack_kernel_create_files_as(struct cred *new,
1040 struct inode *inode)
1041{
1042 struct inode_smack *isp = inode->i_security;
1043
1044 new->security = isp->smk_inode;
1045 return 0;
1046}
1047
e114e473
CS
1048/**
1049 * smack_task_setpgid - Smack check on setting pgid
1050 * @p: the task object
1051 * @pgid: unused
1052 *
1053 * Return 0 if write access is permitted
1054 */
1055static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1056{
c69e8d9c 1057 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1058}
1059
1060/**
1061 * smack_task_getpgid - Smack access check for getpgid
1062 * @p: the object task
1063 *
1064 * Returns 0 if current can read the object task, error code otherwise
1065 */
1066static int smack_task_getpgid(struct task_struct *p)
1067{
c69e8d9c 1068 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1069}
1070
1071/**
1072 * smack_task_getsid - Smack access check for getsid
1073 * @p: the object task
1074 *
1075 * Returns 0 if current can read the object task, error code otherwise
1076 */
1077static int smack_task_getsid(struct task_struct *p)
1078{
c69e8d9c 1079 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1080}
1081
1082/**
1083 * smack_task_getsecid - get the secid of the task
1084 * @p: the object task
1085 * @secid: where to put the result
1086 *
1087 * Sets the secid to contain a u32 version of the smack label.
1088 */
1089static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1090{
c69e8d9c 1091 *secid = smack_to_secid(task_security(p));
e114e473
CS
1092}
1093
1094/**
1095 * smack_task_setnice - Smack check on setting nice
1096 * @p: the task object
1097 * @nice: unused
1098 *
1099 * Return 0 if write access is permitted
1100 */
1101static int smack_task_setnice(struct task_struct *p, int nice)
1102{
bcdca225
CS
1103 int rc;
1104
1105 rc = cap_task_setnice(p, nice);
1106 if (rc == 0)
c69e8d9c 1107 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1108 return rc;
e114e473
CS
1109}
1110
1111/**
1112 * smack_task_setioprio - Smack check on setting ioprio
1113 * @p: the task object
1114 * @ioprio: unused
1115 *
1116 * Return 0 if write access is permitted
1117 */
1118static int smack_task_setioprio(struct task_struct *p, int ioprio)
1119{
bcdca225
CS
1120 int rc;
1121
1122 rc = cap_task_setioprio(p, ioprio);
1123 if (rc == 0)
c69e8d9c 1124 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1125 return rc;
e114e473
CS
1126}
1127
1128/**
1129 * smack_task_getioprio - Smack check on reading ioprio
1130 * @p: the task object
1131 *
1132 * Return 0 if read access is permitted
1133 */
1134static int smack_task_getioprio(struct task_struct *p)
1135{
c69e8d9c 1136 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1137}
1138
1139/**
1140 * smack_task_setscheduler - Smack check on setting scheduler
1141 * @p: the task object
1142 * @policy: unused
1143 * @lp: unused
1144 *
1145 * Return 0 if read access is permitted
1146 */
1147static int smack_task_setscheduler(struct task_struct *p, int policy,
1148 struct sched_param *lp)
1149{
bcdca225
CS
1150 int rc;
1151
1152 rc = cap_task_setscheduler(p, policy, lp);
1153 if (rc == 0)
c69e8d9c 1154 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1155 return rc;
e114e473
CS
1156}
1157
1158/**
1159 * smack_task_getscheduler - Smack check on reading scheduler
1160 * @p: the task object
1161 *
1162 * Return 0 if read access is permitted
1163 */
1164static int smack_task_getscheduler(struct task_struct *p)
1165{
c69e8d9c 1166 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1167}
1168
1169/**
1170 * smack_task_movememory - Smack check on moving memory
1171 * @p: the task object
1172 *
1173 * Return 0 if write access is permitted
1174 */
1175static int smack_task_movememory(struct task_struct *p)
1176{
c69e8d9c 1177 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1178}
1179
1180/**
1181 * smack_task_kill - Smack check on signal delivery
1182 * @p: the task object
1183 * @info: unused
1184 * @sig: unused
1185 * @secid: identifies the smack to use in lieu of current's
1186 *
1187 * Return 0 if write access is permitted
1188 *
1189 * The secid behavior is an artifact of an SELinux hack
1190 * in the USB code. Someday it may go away.
1191 */
1192static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1193 int sig, u32 secid)
1194{
e114e473
CS
1195 /*
1196 * Sending a signal requires that the sender
1197 * can write the receiver.
1198 */
1199 if (secid == 0)
c69e8d9c 1200 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1201 /*
1202 * If the secid isn't 0 we're dealing with some USB IO
1203 * specific behavior. This is not clean. For one thing
1204 * we can't take privilege into account.
1205 */
c69e8d9c 1206 return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE);
e114e473
CS
1207}
1208
1209/**
1210 * smack_task_wait - Smack access check for waiting
1211 * @p: task to wait for
1212 *
1213 * Returns 0 if current can wait for p, error code otherwise
1214 */
1215static int smack_task_wait(struct task_struct *p)
1216{
1217 int rc;
1218
c69e8d9c 1219 rc = smk_access(current_security(), task_security(p), MAY_WRITE);
e114e473
CS
1220 if (rc == 0)
1221 return 0;
1222
1223 /*
1224 * Allow the operation to succeed if either task
1225 * has privilege to perform operations that might
1226 * account for the smack labels having gotten to
1227 * be different in the first place.
1228 *
5cd9c58f 1229 * This breaks the strict subject/object access
e114e473
CS
1230 * control ideal, taking the object's privilege
1231 * state into account in the decision as well as
1232 * the smack value.
1233 */
5cd9c58f 1234 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
e114e473
CS
1235 return 0;
1236
1237 return rc;
1238}
1239
1240/**
1241 * smack_task_to_inode - copy task smack into the inode blob
1242 * @p: task to copy from
251a2a95 1243 * @inode: inode to copy to
e114e473
CS
1244 *
1245 * Sets the smack pointer in the inode security blob
1246 */
1247static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1248{
1249 struct inode_smack *isp = inode->i_security;
c69e8d9c 1250 isp->smk_inode = task_security(p);
e114e473
CS
1251}
1252
1253/*
1254 * Socket hooks.
1255 */
1256
1257/**
1258 * smack_sk_alloc_security - Allocate a socket blob
1259 * @sk: the socket
1260 * @family: unused
251a2a95 1261 * @gfp_flags: memory allocation flags
e114e473
CS
1262 *
1263 * Assign Smack pointers to current
1264 *
1265 * Returns 0 on success, -ENOMEM is there's no memory
1266 */
1267static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1268{
86a264ab 1269 char *csp = current_security();
e114e473
CS
1270 struct socket_smack *ssp;
1271
1272 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1273 if (ssp == NULL)
1274 return -ENOMEM;
1275
1276 ssp->smk_in = csp;
1277 ssp->smk_out = csp;
6d3dc07c 1278 ssp->smk_labeled = SMACK_CIPSO_SOCKET;
e114e473
CS
1279 ssp->smk_packet[0] = '\0';
1280
1281 sk->sk_security = ssp;
1282
1283 return 0;
1284}
1285
1286/**
1287 * smack_sk_free_security - Free a socket blob
1288 * @sk: the socket
1289 *
1290 * Clears the blob pointer
1291 */
1292static void smack_sk_free_security(struct sock *sk)
1293{
1294 kfree(sk->sk_security);
1295}
1296
1297/**
1298 * smack_set_catset - convert a capset to netlabel mls categories
1299 * @catset: the Smack categories
1300 * @sap: where to put the netlabel categories
1301 *
1302 * Allocates and fills attr.mls.cat
1303 */
1304static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1305{
1306 unsigned char *cp;
1307 unsigned char m;
1308 int cat;
1309 int rc;
1310 int byte;
1311
c60264c4 1312 if (!catset)
e114e473
CS
1313 return;
1314
1315 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1316 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1317 sap->attr.mls.cat->startbit = 0;
1318
1319 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1320 for (m = 0x80; m != 0; m >>= 1, cat++) {
1321 if ((m & *cp) == 0)
1322 continue;
1323 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1324 cat, GFP_ATOMIC);
1325 }
1326}
1327
1328/**
1329 * smack_to_secattr - fill a secattr from a smack value
1330 * @smack: the smack value
1331 * @nlsp: where the result goes
1332 *
1333 * Casey says that CIPSO is good enough for now.
1334 * It can be used to effect.
1335 * It can also be abused to effect when necessary.
1336 * Appologies to the TSIG group in general and GW in particular.
1337 */
1338static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1339{
1340 struct smack_cipso cipso;
1341 int rc;
1342
6d3dc07c
CS
1343 nlsp->domain = smack;
1344 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
e114e473 1345
6d3dc07c
CS
1346 rc = smack_to_cipso(smack, &cipso);
1347 if (rc == 0) {
1348 nlsp->attr.mls.lvl = cipso.smk_level;
1349 smack_set_catset(cipso.smk_catset, nlsp);
1350 } else {
1351 nlsp->attr.mls.lvl = smack_cipso_direct;
1352 smack_set_catset(smack, nlsp);
e114e473
CS
1353 }
1354}
1355
1356/**
1357 * smack_netlabel - Set the secattr on a socket
1358 * @sk: the socket
6d3dc07c 1359 * @labeled: socket label scheme
e114e473
CS
1360 *
1361 * Convert the outbound smack value (smk_out) to a
1362 * secattr and attach it to the socket.
1363 *
1364 * Returns 0 on success or an error code
1365 */
6d3dc07c 1366static int smack_netlabel(struct sock *sk, int labeled)
e114e473 1367{
2e1d146a 1368 struct socket_smack *ssp;
e114e473 1369 struct netlbl_lsm_secattr secattr;
6d3dc07c 1370 int rc = 0;
e114e473 1371
2e1d146a 1372 ssp = sk->sk_security;
6d3dc07c
CS
1373 /*
1374 * Usually the netlabel code will handle changing the
1375 * packet labeling based on the label.
1376 * The case of a single label host is different, because
1377 * a single label host should never get a labeled packet
1378 * even though the label is usually associated with a packet
1379 * label.
1380 */
1381 local_bh_disable();
1382 bh_lock_sock_nested(sk);
1383
1384 if (ssp->smk_out == smack_net_ambient ||
1385 labeled == SMACK_UNLABELED_SOCKET)
1386 netlbl_sock_delattr(sk);
1387 else {
1388 netlbl_secattr_init(&secattr);
1389 smack_to_secattr(ssp->smk_out, &secattr);
389fb800 1390 rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
6d3dc07c
CS
1391 netlbl_secattr_destroy(&secattr);
1392 }
1393
1394 bh_unlock_sock(sk);
1395 local_bh_enable();
1396 /*
1397 * Remember the label scheme used so that it is not
1398 * necessary to do the netlabel setting if it has not
1399 * changed the next time through.
1400 *
1401 * The -EDESTADDRREQ case is an indication that there's
1402 * a single level host involved.
1403 */
1404 if (rc == 0)
1405 ssp->smk_labeled = labeled;
4bc87e62 1406
e114e473
CS
1407 return rc;
1408}
1409
1410/**
1411 * smack_inode_setsecurity - set smack xattrs
1412 * @inode: the object
1413 * @name: attribute name
1414 * @value: attribute value
1415 * @size: size of the attribute
1416 * @flags: unused
1417 *
1418 * Sets the named attribute in the appropriate blob
1419 *
1420 * Returns 0 on success, or an error code
1421 */
1422static int smack_inode_setsecurity(struct inode *inode, const char *name,
1423 const void *value, size_t size, int flags)
1424{
1425 char *sp;
1426 struct inode_smack *nsp = inode->i_security;
1427 struct socket_smack *ssp;
1428 struct socket *sock;
4bc87e62 1429 int rc = 0;
e114e473
CS
1430
1431 if (value == NULL || size > SMK_LABELLEN)
1432 return -EACCES;
1433
1434 sp = smk_import(value, size);
1435 if (sp == NULL)
1436 return -EINVAL;
1437
1438 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1439 nsp->smk_inode = sp;
1440 return 0;
1441 }
1442 /*
1443 * The rest of the Smack xattrs are only on sockets.
1444 */
1445 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1446 return -EOPNOTSUPP;
1447
1448 sock = SOCKET_I(inode);
2e1d146a 1449 if (sock == NULL || sock->sk == NULL)
e114e473
CS
1450 return -EOPNOTSUPP;
1451
1452 ssp = sock->sk->sk_security;
1453
1454 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1455 ssp->smk_in = sp;
1456 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1457 ssp->smk_out = sp;
6d3dc07c 1458 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
4bc87e62
CS
1459 if (rc != 0)
1460 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
1461 __func__, -rc);
e114e473
CS
1462 } else
1463 return -EOPNOTSUPP;
1464
1465 return 0;
1466}
1467
1468/**
1469 * smack_socket_post_create - finish socket setup
1470 * @sock: the socket
1471 * @family: protocol family
1472 * @type: unused
1473 * @protocol: unused
1474 * @kern: unused
1475 *
1476 * Sets the netlabel information on the socket
1477 *
1478 * Returns 0 on success, and error code otherwise
1479 */
1480static int smack_socket_post_create(struct socket *sock, int family,
1481 int type, int protocol, int kern)
1482{
2e1d146a 1483 if (family != PF_INET || sock->sk == NULL)
e114e473
CS
1484 return 0;
1485 /*
1486 * Set the outbound netlbl.
1487 */
6d3dc07c
CS
1488 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
1489}
1490
1491
1492/**
1493 * smack_host_label - check host based restrictions
1494 * @sip: the object end
1495 *
1496 * looks for host based access restrictions
1497 *
1498 * This version will only be appropriate for really small
211a40c0 1499 * sets of single label hosts.
6d3dc07c
CS
1500 *
1501 * Returns the label of the far end or NULL if it's not special.
1502 */
1503static char *smack_host_label(struct sockaddr_in *sip)
1504{
1505 struct smk_netlbladdr *snp;
6d3dc07c 1506 struct in_addr *siap = &sip->sin_addr;
6d3dc07c
CS
1507
1508 if (siap->s_addr == 0)
1509 return NULL;
1510
7198e2ee
EB
1511 rcu_read_lock();
1512 list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) {
6d3dc07c 1513 /*
211a40c0 1514 * we break after finding the first match because
1515 * the list is sorted from longest to shortest mask
1516 * so we have found the most specific match
6d3dc07c 1517 */
211a40c0 1518 if ((&snp->smk_host.sin_addr)->s_addr ==
1519 (siap->s_addr & (&snp->smk_mask)->s_addr)) {
7198e2ee 1520 rcu_read_unlock();
6d3dc07c 1521 return snp->smk_label;
211a40c0 1522 }
6d3dc07c 1523 }
7198e2ee 1524 rcu_read_unlock();
211a40c0 1525 return NULL;
6d3dc07c
CS
1526}
1527
1528/**
1529 * smack_socket_connect - connect access check
1530 * @sock: the socket
1531 * @sap: the other end
1532 * @addrlen: size of sap
1533 *
1534 * Verifies that a connection may be possible
1535 *
1536 * Returns 0 on success, and error code otherwise
1537 */
1538static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
1539 int addrlen)
1540{
1541 struct socket_smack *ssp = sock->sk->sk_security;
1542 char *hostsp;
1543 int rc;
1544
1545 if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
1546 return 0;
1547
1548 if (addrlen < sizeof(struct sockaddr_in))
1549 return -EINVAL;
1550
1551 hostsp = smack_host_label((struct sockaddr_in *)sap);
1552 if (hostsp == NULL) {
1553 if (ssp->smk_labeled != SMACK_CIPSO_SOCKET)
1554 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
1555 return 0;
1556 }
1557
1558 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE);
1559 if (rc != 0)
1560 return rc;
1561
1562 if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET)
1563 return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET);
1564 return 0;
e114e473
CS
1565}
1566
1567/**
1568 * smack_flags_to_may - convert S_ to MAY_ values
1569 * @flags: the S_ value
1570 *
1571 * Returns the equivalent MAY_ value
1572 */
1573static int smack_flags_to_may(int flags)
1574{
1575 int may = 0;
1576
1577 if (flags & S_IRUGO)
1578 may |= MAY_READ;
1579 if (flags & S_IWUGO)
1580 may |= MAY_WRITE;
1581 if (flags & S_IXUGO)
1582 may |= MAY_EXEC;
1583
1584 return may;
1585}
1586
1587/**
1588 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
1589 * @msg: the object
1590 *
1591 * Returns 0
1592 */
1593static int smack_msg_msg_alloc_security(struct msg_msg *msg)
1594{
86a264ab 1595 msg->security = current_security();
e114e473
CS
1596 return 0;
1597}
1598
1599/**
1600 * smack_msg_msg_free_security - Clear the security blob for msg_msg
1601 * @msg: the object
1602 *
1603 * Clears the blob pointer
1604 */
1605static void smack_msg_msg_free_security(struct msg_msg *msg)
1606{
1607 msg->security = NULL;
1608}
1609
1610/**
1611 * smack_of_shm - the smack pointer for the shm
1612 * @shp: the object
1613 *
1614 * Returns a pointer to the smack value
1615 */
1616static char *smack_of_shm(struct shmid_kernel *shp)
1617{
1618 return (char *)shp->shm_perm.security;
1619}
1620
1621/**
1622 * smack_shm_alloc_security - Set the security blob for shm
1623 * @shp: the object
1624 *
1625 * Returns 0
1626 */
1627static int smack_shm_alloc_security(struct shmid_kernel *shp)
1628{
1629 struct kern_ipc_perm *isp = &shp->shm_perm;
1630
86a264ab 1631 isp->security = current_security();
e114e473
CS
1632 return 0;
1633}
1634
1635/**
1636 * smack_shm_free_security - Clear the security blob for shm
1637 * @shp: the object
1638 *
1639 * Clears the blob pointer
1640 */
1641static void smack_shm_free_security(struct shmid_kernel *shp)
1642{
1643 struct kern_ipc_perm *isp = &shp->shm_perm;
1644
1645 isp->security = NULL;
1646}
1647
1648/**
1649 * smack_shm_associate - Smack access check for shm
1650 * @shp: the object
1651 * @shmflg: access requested
1652 *
1653 * Returns 0 if current has the requested access, error code otherwise
1654 */
1655static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
1656{
1657 char *ssp = smack_of_shm(shp);
1658 int may;
1659
1660 may = smack_flags_to_may(shmflg);
1661 return smk_curacc(ssp, may);
1662}
1663
1664/**
1665 * smack_shm_shmctl - Smack access check for shm
1666 * @shp: the object
1667 * @cmd: what it wants to do
1668 *
1669 * Returns 0 if current has the requested access, error code otherwise
1670 */
1671static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
1672{
1d252fb8 1673 char *ssp;
e114e473
CS
1674 int may;
1675
1676 switch (cmd) {
1677 case IPC_STAT:
1678 case SHM_STAT:
1679 may = MAY_READ;
1680 break;
1681 case IPC_SET:
1682 case SHM_LOCK:
1683 case SHM_UNLOCK:
1684 case IPC_RMID:
1685 may = MAY_READWRITE;
1686 break;
1687 case IPC_INFO:
1688 case SHM_INFO:
1689 /*
1690 * System level information.
1691 */
1692 return 0;
1693 default:
1694 return -EINVAL;
1695 }
1696
1d252fb8 1697 ssp = smack_of_shm(shp);
e114e473
CS
1698 return smk_curacc(ssp, may);
1699}
1700
1701/**
1702 * smack_shm_shmat - Smack access for shmat
1703 * @shp: the object
1704 * @shmaddr: unused
1705 * @shmflg: access requested
1706 *
1707 * Returns 0 if current has the requested access, error code otherwise
1708 */
1709static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
1710 int shmflg)
1711{
1712 char *ssp = smack_of_shm(shp);
1713 int may;
1714
1715 may = smack_flags_to_may(shmflg);
1716 return smk_curacc(ssp, may);
1717}
1718
1719/**
1720 * smack_of_sem - the smack pointer for the sem
1721 * @sma: the object
1722 *
1723 * Returns a pointer to the smack value
1724 */
1725static char *smack_of_sem(struct sem_array *sma)
1726{
1727 return (char *)sma->sem_perm.security;
1728}
1729
1730/**
1731 * smack_sem_alloc_security - Set the security blob for sem
1732 * @sma: the object
1733 *
1734 * Returns 0
1735 */
1736static int smack_sem_alloc_security(struct sem_array *sma)
1737{
1738 struct kern_ipc_perm *isp = &sma->sem_perm;
1739
86a264ab 1740 isp->security = current_security();
e114e473
CS
1741 return 0;
1742}
1743
1744/**
1745 * smack_sem_free_security - Clear the security blob for sem
1746 * @sma: the object
1747 *
1748 * Clears the blob pointer
1749 */
1750static void smack_sem_free_security(struct sem_array *sma)
1751{
1752 struct kern_ipc_perm *isp = &sma->sem_perm;
1753
1754 isp->security = NULL;
1755}
1756
1757/**
1758 * smack_sem_associate - Smack access check for sem
1759 * @sma: the object
1760 * @semflg: access requested
1761 *
1762 * Returns 0 if current has the requested access, error code otherwise
1763 */
1764static int smack_sem_associate(struct sem_array *sma, int semflg)
1765{
1766 char *ssp = smack_of_sem(sma);
1767 int may;
1768
1769 may = smack_flags_to_may(semflg);
1770 return smk_curacc(ssp, may);
1771}
1772
1773/**
1774 * smack_sem_shmctl - Smack access check for sem
1775 * @sma: the object
1776 * @cmd: what it wants to do
1777 *
1778 * Returns 0 if current has the requested access, error code otherwise
1779 */
1780static int smack_sem_semctl(struct sem_array *sma, int cmd)
1781{
1d252fb8 1782 char *ssp;
e114e473
CS
1783 int may;
1784
1785 switch (cmd) {
1786 case GETPID:
1787 case GETNCNT:
1788 case GETZCNT:
1789 case GETVAL:
1790 case GETALL:
1791 case IPC_STAT:
1792 case SEM_STAT:
1793 may = MAY_READ;
1794 break;
1795 case SETVAL:
1796 case SETALL:
1797 case IPC_RMID:
1798 case IPC_SET:
1799 may = MAY_READWRITE;
1800 break;
1801 case IPC_INFO:
1802 case SEM_INFO:
1803 /*
1804 * System level information
1805 */
1806 return 0;
1807 default:
1808 return -EINVAL;
1809 }
1810
1d252fb8 1811 ssp = smack_of_sem(sma);
e114e473
CS
1812 return smk_curacc(ssp, may);
1813}
1814
1815/**
1816 * smack_sem_semop - Smack checks of semaphore operations
1817 * @sma: the object
1818 * @sops: unused
1819 * @nsops: unused
1820 * @alter: unused
1821 *
1822 * Treated as read and write in all cases.
1823 *
1824 * Returns 0 if access is allowed, error code otherwise
1825 */
1826static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
1827 unsigned nsops, int alter)
1828{
1829 char *ssp = smack_of_sem(sma);
1830
1831 return smk_curacc(ssp, MAY_READWRITE);
1832}
1833
1834/**
1835 * smack_msg_alloc_security - Set the security blob for msg
1836 * @msq: the object
1837 *
1838 * Returns 0
1839 */
1840static int smack_msg_queue_alloc_security(struct msg_queue *msq)
1841{
1842 struct kern_ipc_perm *kisp = &msq->q_perm;
1843
86a264ab 1844 kisp->security = current_security();
e114e473
CS
1845 return 0;
1846}
1847
1848/**
1849 * smack_msg_free_security - Clear the security blob for msg
1850 * @msq: the object
1851 *
1852 * Clears the blob pointer
1853 */
1854static void smack_msg_queue_free_security(struct msg_queue *msq)
1855{
1856 struct kern_ipc_perm *kisp = &msq->q_perm;
1857
1858 kisp->security = NULL;
1859}
1860
1861/**
1862 * smack_of_msq - the smack pointer for the msq
1863 * @msq: the object
1864 *
1865 * Returns a pointer to the smack value
1866 */
1867static char *smack_of_msq(struct msg_queue *msq)
1868{
1869 return (char *)msq->q_perm.security;
1870}
1871
1872/**
1873 * smack_msg_queue_associate - Smack access check for msg_queue
1874 * @msq: the object
1875 * @msqflg: access requested
1876 *
1877 * Returns 0 if current has the requested access, error code otherwise
1878 */
1879static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
1880{
1881 char *msp = smack_of_msq(msq);
1882 int may;
1883
1884 may = smack_flags_to_may(msqflg);
1885 return smk_curacc(msp, may);
1886}
1887
1888/**
1889 * smack_msg_queue_msgctl - Smack access check for msg_queue
1890 * @msq: the object
1891 * @cmd: what it wants to do
1892 *
1893 * Returns 0 if current has the requested access, error code otherwise
1894 */
1895static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
1896{
1d252fb8 1897 char *msp;
e114e473
CS
1898 int may;
1899
1900 switch (cmd) {
1901 case IPC_STAT:
1902 case MSG_STAT:
1903 may = MAY_READ;
1904 break;
1905 case IPC_SET:
1906 case IPC_RMID:
1907 may = MAY_READWRITE;
1908 break;
1909 case IPC_INFO:
1910 case MSG_INFO:
1911 /*
1912 * System level information
1913 */
1914 return 0;
1915 default:
1916 return -EINVAL;
1917 }
1918
1d252fb8 1919 msp = smack_of_msq(msq);
e114e473
CS
1920 return smk_curacc(msp, may);
1921}
1922
1923/**
1924 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1925 * @msq: the object
1926 * @msg: unused
1927 * @msqflg: access requested
1928 *
1929 * Returns 0 if current has the requested access, error code otherwise
1930 */
1931static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
1932 int msqflg)
1933{
1934 char *msp = smack_of_msq(msq);
1935 int rc;
1936
1937 rc = smack_flags_to_may(msqflg);
1938 return smk_curacc(msp, rc);
1939}
1940
1941/**
1942 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1943 * @msq: the object
1944 * @msg: unused
1945 * @target: unused
1946 * @type: unused
1947 * @mode: unused
1948 *
1949 * Returns 0 if current has read and write access, error code otherwise
1950 */
1951static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
1952 struct task_struct *target, long type, int mode)
1953{
1954 char *msp = smack_of_msq(msq);
1955
1956 return smk_curacc(msp, MAY_READWRITE);
1957}
1958
1959/**
1960 * smack_ipc_permission - Smack access for ipc_permission()
1961 * @ipp: the object permissions
1962 * @flag: access requested
1963 *
1964 * Returns 0 if current has read and write access, error code otherwise
1965 */
1966static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
1967{
1968 char *isp = ipp->security;
1969 int may;
1970
1971 may = smack_flags_to_may(flag);
1972 return smk_curacc(isp, may);
1973}
1974
d20bdda6
AD
1975/**
1976 * smack_ipc_getsecid - Extract smack security id
251a2a95 1977 * @ipp: the object permissions
d20bdda6
AD
1978 * @secid: where result will be saved
1979 */
1980static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
1981{
1982 char *smack = ipp->security;
1983
1984 *secid = smack_to_secid(smack);
1985}
1986
e114e473
CS
1987/**
1988 * smack_d_instantiate - Make sure the blob is correct on an inode
1989 * @opt_dentry: unused
1990 * @inode: the object
1991 *
1992 * Set the inode's security blob if it hasn't been done already.
1993 */
1994static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
1995{
1996 struct super_block *sbp;
1997 struct superblock_smack *sbsp;
1998 struct inode_smack *isp;
86a264ab 1999 char *csp = current_security();
e114e473
CS
2000 char *fetched;
2001 char *final;
2002 struct dentry *dp;
2003
2004 if (inode == NULL)
2005 return;
2006
2007 isp = inode->i_security;
2008
2009 mutex_lock(&isp->smk_lock);
2010 /*
2011 * If the inode is already instantiated
2012 * take the quick way out
2013 */
2014 if (isp->smk_flags & SMK_INODE_INSTANT)
2015 goto unlockandout;
2016
2017 sbp = inode->i_sb;
2018 sbsp = sbp->s_security;
2019 /*
2020 * We're going to use the superblock default label
2021 * if there's no label on the file.
2022 */
2023 final = sbsp->smk_default;
2024
e97dcb0e
CS
2025 /*
2026 * If this is the root inode the superblock
2027 * may be in the process of initialization.
2028 * If that is the case use the root value out
2029 * of the superblock.
2030 */
2031 if (opt_dentry->d_parent == opt_dentry) {
2032 isp->smk_inode = sbsp->smk_root;
2033 isp->smk_flags |= SMK_INODE_INSTANT;
2034 goto unlockandout;
2035 }
2036
e114e473
CS
2037 /*
2038 * This is pretty hackish.
2039 * Casey says that we shouldn't have to do
2040 * file system specific code, but it does help
2041 * with keeping it simple.
2042 */
2043 switch (sbp->s_magic) {
2044 case SMACK_MAGIC:
2045 /*
2046 * Casey says that it's a little embarassing
2047 * that the smack file system doesn't do
2048 * extended attributes.
2049 */
2050 final = smack_known_star.smk_known;
2051 break;
2052 case PIPEFS_MAGIC:
2053 /*
2054 * Casey says pipes are easy (?)
2055 */
2056 final = smack_known_star.smk_known;
2057 break;
2058 case DEVPTS_SUPER_MAGIC:
2059 /*
2060 * devpts seems content with the label of the task.
2061 * Programs that change smack have to treat the
2062 * pty with respect.
2063 */
2064 final = csp;
2065 break;
2066 case SOCKFS_MAGIC:
2067 /*
2068 * Casey says sockets get the smack of the task.
2069 */
2070 final = csp;
2071 break;
2072 case PROC_SUPER_MAGIC:
2073 /*
2074 * Casey says procfs appears not to care.
2075 * The superblock default suffices.
2076 */
2077 break;
2078 case TMPFS_MAGIC:
2079 /*
2080 * Device labels should come from the filesystem,
2081 * but watch out, because they're volitile,
2082 * getting recreated on every reboot.
2083 */
2084 final = smack_known_star.smk_known;
2085 /*
2086 * No break.
2087 *
2088 * If a smack value has been set we want to use it,
2089 * but since tmpfs isn't giving us the opportunity
2090 * to set mount options simulate setting the
2091 * superblock default.
2092 */
2093 default:
2094 /*
2095 * This isn't an understood special case.
2096 * Get the value from the xattr.
2097 *
2098 * No xattr support means, alas, no SMACK label.
2099 * Use the aforeapplied default.
2100 * It would be curious if the label of the task
2101 * does not match that assigned.
2102 */
2103 if (inode->i_op->getxattr == NULL)
2104 break;
2105 /*
2106 * Get the dentry for xattr.
2107 */
2108 if (opt_dentry == NULL) {
2109 dp = d_find_alias(inode);
2110 if (dp == NULL)
2111 break;
2112 } else {
2113 dp = dget(opt_dentry);
2114 if (dp == NULL)
2115 break;
2116 }
2117
2118 fetched = smk_fetch(inode, dp);
2119 if (fetched != NULL)
2120 final = fetched;
2121
2122 dput(dp);
2123 break;
2124 }
2125
2126 if (final == NULL)
2127 isp->smk_inode = csp;
2128 else
2129 isp->smk_inode = final;
2130
2131 isp->smk_flags |= SMK_INODE_INSTANT;
2132
2133unlockandout:
2134 mutex_unlock(&isp->smk_lock);
2135 return;
2136}
2137
2138/**
2139 * smack_getprocattr - Smack process attribute access
2140 * @p: the object task
2141 * @name: the name of the attribute in /proc/.../attr
2142 * @value: where to put the result
2143 *
2144 * Places a copy of the task Smack into value
2145 *
2146 * Returns the length of the smack label or an error code
2147 */
2148static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2149{
2150 char *cp;
2151 int slen;
2152
2153 if (strcmp(name, "current") != 0)
2154 return -EINVAL;
2155
c69e8d9c 2156 cp = kstrdup(task_security(p), GFP_KERNEL);
e114e473
CS
2157 if (cp == NULL)
2158 return -ENOMEM;
2159
2160 slen = strlen(cp);
2161 *value = cp;
2162 return slen;
2163}
2164
2165/**
2166 * smack_setprocattr - Smack process attribute setting
2167 * @p: the object task
2168 * @name: the name of the attribute in /proc/.../attr
2169 * @value: the value to set
2170 * @size: the size of the value
2171 *
2172 * Sets the Smack value of the task. Only setting self
2173 * is permitted and only with privilege
2174 *
2175 * Returns the length of the smack label or an error code
2176 */
2177static int smack_setprocattr(struct task_struct *p, char *name,
2178 void *value, size_t size)
2179{
d84f4f99 2180 struct cred *new;
e114e473
CS
2181 char *newsmack;
2182
e114e473
CS
2183 /*
2184 * Changing another process' Smack value is too dangerous
2185 * and supports no sane use case.
2186 */
2187 if (p != current)
2188 return -EPERM;
2189
5cd9c58f
DH
2190 if (!capable(CAP_MAC_ADMIN))
2191 return -EPERM;
2192
e114e473
CS
2193 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2194 return -EINVAL;
2195
2196 if (strcmp(name, "current") != 0)
2197 return -EINVAL;
2198
2199 newsmack = smk_import(value, size);
2200 if (newsmack == NULL)
2201 return -EINVAL;
2202
6d3dc07c
CS
2203 /*
2204 * No process is ever allowed the web ("@") label.
2205 */
2206 if (newsmack == smack_known_web.smk_known)
2207 return -EPERM;
2208
d84f4f99 2209 new = prepare_creds();
6d3dc07c 2210 if (new == NULL)
d84f4f99
DH
2211 return -ENOMEM;
2212 new->security = newsmack;
2213 commit_creds(new);
e114e473
CS
2214 return size;
2215}
2216
2217/**
2218 * smack_unix_stream_connect - Smack access on UDS
2219 * @sock: one socket
2220 * @other: the other socket
2221 * @newsk: unused
2222 *
2223 * Return 0 if a subject with the smack of sock could access
2224 * an object with the smack of other, otherwise an error code
2225 */
2226static int smack_unix_stream_connect(struct socket *sock,
2227 struct socket *other, struct sock *newsk)
2228{
2229 struct inode *sp = SOCK_INODE(sock);
2230 struct inode *op = SOCK_INODE(other);
2231
2232 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE);
2233}
2234
2235/**
2236 * smack_unix_may_send - Smack access on UDS
2237 * @sock: one socket
2238 * @other: the other socket
2239 *
2240 * Return 0 if a subject with the smack of sock could access
2241 * an object with the smack of other, otherwise an error code
2242 */
2243static int smack_unix_may_send(struct socket *sock, struct socket *other)
2244{
2245 struct inode *sp = SOCK_INODE(sock);
2246 struct inode *op = SOCK_INODE(other);
2247
2248 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE);
2249}
2250
6d3dc07c
CS
2251/**
2252 * smack_socket_sendmsg - Smack check based on destination host
2253 * @sock: the socket
251a2a95 2254 * @msg: the message
6d3dc07c
CS
2255 * @size: the size of the message
2256 *
2257 * Return 0 if the current subject can write to the destination
2258 * host. This is only a question if the destination is a single
2259 * label host.
2260 */
2261static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
2262 int size)
2263{
2264 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
2265 struct socket_smack *ssp = sock->sk->sk_security;
2266 char *hostsp;
2267 int rc;
2268
2269 /*
2270 * Perfectly reasonable for this to be NULL
2271 */
2272 if (sip == NULL || sip->sin_family != PF_INET)
2273 return 0;
2274
2275 hostsp = smack_host_label(sip);
2276 if (hostsp == NULL) {
2277 if (ssp->smk_labeled != SMACK_CIPSO_SOCKET)
2278 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2279 return 0;
2280 }
2281
2282 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE);
2283 if (rc != 0)
2284 return rc;
2285
2286 if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET)
2287 return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET);
2288
2289 return 0;
2290
2291}
2292
2293
e114e473 2294/**
251a2a95 2295 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
e114e473
CS
2296 * @sap: netlabel secattr
2297 * @sip: where to put the result
2298 *
2299 * Copies a smack label into sip
2300 */
2301static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2302{
2303 char smack[SMK_LABELLEN];
6d3dc07c 2304 char *sp;
e114e473
CS
2305 int pcat;
2306
6d3dc07c 2307 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
e114e473 2308 /*
6d3dc07c 2309 * Looks like a CIPSO packet.
e114e473
CS
2310 * If there are flags but no level netlabel isn't
2311 * behaving the way we expect it to.
2312 *
6d3dc07c 2313 * Get the categories, if any
e114e473
CS
2314 * Without guidance regarding the smack value
2315 * for the packet fall back on the network
2316 * ambient value.
2317 */
6d3dc07c
CS
2318 memset(smack, '\0', SMK_LABELLEN);
2319 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2320 for (pcat = -1;;) {
2321 pcat = netlbl_secattr_catmap_walk(
2322 sap->attr.mls.cat, pcat + 1);
2323 if (pcat < 0)
2324 break;
2325 smack_catset_bit(pcat, smack);
2326 }
2327 /*
2328 * If it is CIPSO using smack direct mapping
2329 * we are already done. WeeHee.
2330 */
2331 if (sap->attr.mls.lvl == smack_cipso_direct) {
2332 memcpy(sip, smack, SMK_MAXLEN);
2333 return;
2334 }
2335 /*
2336 * Look it up in the supplied table if it is not
2337 * a direct mapping.
2338 */
2339 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
e114e473
CS
2340 return;
2341 }
6d3dc07c
CS
2342 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
2343 /*
2344 * Looks like a fallback, which gives us a secid.
2345 */
2346 sp = smack_from_secid(sap->attr.secid);
2347 /*
2348 * This has got to be a bug because it is
2349 * impossible to specify a fallback without
2350 * specifying the label, which will ensure
2351 * it has a secid, and the only way to get a
2352 * secid is from a fallback.
2353 */
2354 BUG_ON(sp == NULL);
2355 strncpy(sip, sp, SMK_MAXLEN);
e114e473
CS
2356 return;
2357 }
2358 /*
6d3dc07c
CS
2359 * Without guidance regarding the smack value
2360 * for the packet fall back on the network
2361 * ambient value.
e114e473 2362 */
6d3dc07c 2363 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
e114e473
CS
2364 return;
2365}
2366
2367/**
2368 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2369 * @sk: socket
2370 * @skb: packet
2371 *
2372 * Returns 0 if the packet should be delivered, an error code otherwise
2373 */
2374static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2375{
2376 struct netlbl_lsm_secattr secattr;
2377 struct socket_smack *ssp = sk->sk_security;
2378 char smack[SMK_LABELLEN];
6d3dc07c 2379 char *csp;
e114e473
CS
2380 int rc;
2381
2382 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2383 return 0;
2384
2385 /*
2386 * Translate what netlabel gave us.
2387 */
e114e473 2388 netlbl_secattr_init(&secattr);
6d3dc07c 2389
e114e473 2390 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
6d3dc07c 2391 if (rc == 0) {
e114e473 2392 smack_from_secattr(&secattr, smack);
6d3dc07c
CS
2393 csp = smack;
2394 } else
2395 csp = smack_net_ambient;
2396
e114e473 2397 netlbl_secattr_destroy(&secattr);
6d3dc07c 2398
e114e473
CS
2399 /*
2400 * Receiving a packet requires that the other end
2401 * be able to write here. Read access is not required.
2402 * This is the simplist possible security model
2403 * for networking.
2404 */
6d3dc07c 2405 rc = smk_access(csp, ssp->smk_in, MAY_WRITE);
a8134296
PM
2406 if (rc != 0)
2407 netlbl_skbuff_err(skb, rc, 0);
2408 return rc;
e114e473
CS
2409}
2410
2411/**
2412 * smack_socket_getpeersec_stream - pull in packet label
2413 * @sock: the socket
2414 * @optval: user's destination
2415 * @optlen: size thereof
251a2a95 2416 * @len: max thereof
e114e473
CS
2417 *
2418 * returns zero on success, an error code otherwise
2419 */
2420static int smack_socket_getpeersec_stream(struct socket *sock,
2421 char __user *optval,
2422 int __user *optlen, unsigned len)
2423{
2424 struct socket_smack *ssp;
2425 int slen;
2426 int rc = 0;
2427
2428 ssp = sock->sk->sk_security;
2429 slen = strlen(ssp->smk_packet) + 1;
2430
2431 if (slen > len)
2432 rc = -ERANGE;
2433 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2434 rc = -EFAULT;
2435
2436 if (put_user(slen, optlen) != 0)
2437 rc = -EFAULT;
2438
2439 return rc;
2440}
2441
2442
2443/**
2444 * smack_socket_getpeersec_dgram - pull in packet label
2445 * @sock: the socket
2446 * @skb: packet data
2447 * @secid: pointer to where to put the secid of the packet
2448 *
2449 * Sets the netlabel socket state on sk from parent
2450 */
2451static int smack_socket_getpeersec_dgram(struct socket *sock,
2452 struct sk_buff *skb, u32 *secid)
2453
2454{
2455 struct netlbl_lsm_secattr secattr;
2456 struct sock *sk;
2457 char smack[SMK_LABELLEN];
2458 int family = PF_INET;
2459 u32 s;
2460 int rc;
2461
2462 /*
2463 * Only works for families with packets.
2464 */
2465 if (sock != NULL) {
2466 sk = sock->sk;
2467 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2468 return 0;
2469 family = sk->sk_family;
2470 }
2471 /*
2472 * Translate what netlabel gave us.
2473 */
e114e473
CS
2474 netlbl_secattr_init(&secattr);
2475 rc = netlbl_skbuff_getattr(skb, family, &secattr);
2476 if (rc == 0)
2477 smack_from_secattr(&secattr, smack);
2478 netlbl_secattr_destroy(&secattr);
2479
2480 /*
2481 * Give up if we couldn't get anything
2482 */
2483 if (rc != 0)
2484 return rc;
2485
2486 s = smack_to_secid(smack);
2487 if (s == 0)
2488 return -EINVAL;
2489
2490 *secid = s;
2491 return 0;
2492}
2493
2494/**
2495 * smack_sock_graft - graft access state between two sockets
2496 * @sk: fresh sock
2497 * @parent: donor socket
2498 *
2499 * Sets the netlabel socket state on sk from parent
2500 */
2501static void smack_sock_graft(struct sock *sk, struct socket *parent)
2502{
2503 struct socket_smack *ssp;
2504 int rc;
2505
2506 if (sk == NULL)
2507 return;
2508
2509 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2510 return;
2511
2512 ssp = sk->sk_security;
86a264ab 2513 ssp->smk_in = ssp->smk_out = current_security();
e114e473
CS
2514 ssp->smk_packet[0] = '\0';
2515
6d3dc07c 2516 rc = smack_netlabel(sk, SMACK_CIPSO_SOCKET);
4bc87e62
CS
2517 if (rc != 0)
2518 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
2519 __func__, -rc);
e114e473
CS
2520}
2521
2522/**
2523 * smack_inet_conn_request - Smack access check on connect
2524 * @sk: socket involved
2525 * @skb: packet
2526 * @req: unused
2527 *
2528 * Returns 0 if a task with the packet label could write to
2529 * the socket, otherwise an error code
2530 */
2531static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
2532 struct request_sock *req)
2533{
2534 struct netlbl_lsm_secattr skb_secattr;
2535 struct socket_smack *ssp = sk->sk_security;
2536 char smack[SMK_LABELLEN];
2537 int rc;
2538
2539 if (skb == NULL)
2540 return -EACCES;
2541
e114e473
CS
2542 netlbl_secattr_init(&skb_secattr);
2543 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr);
2544 if (rc == 0)
2545 smack_from_secattr(&skb_secattr, smack);
2546 else
2547 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
2548 netlbl_secattr_destroy(&skb_secattr);
2549 /*
2550 * Receiving a packet requires that the other end
2551 * be able to write here. Read access is not required.
2552 *
2553 * If the request is successful save the peer's label
2554 * so that SO_PEERCRED can report it.
2555 */
2556 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2557 if (rc == 0)
2558 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
2559
2560 return rc;
2561}
2562
2563/*
2564 * Key management security hooks
2565 *
2566 * Casey has not tested key support very heavily.
2567 * The permission check is most likely too restrictive.
2568 * If you care about keys please have a look.
2569 */
2570#ifdef CONFIG_KEYS
2571
2572/**
2573 * smack_key_alloc - Set the key security blob
2574 * @key: object
d84f4f99 2575 * @cred: the credentials to use
e114e473
CS
2576 * @flags: unused
2577 *
2578 * No allocation required
2579 *
2580 * Returns 0
2581 */
d84f4f99 2582static int smack_key_alloc(struct key *key, const struct cred *cred,
e114e473
CS
2583 unsigned long flags)
2584{
d84f4f99 2585 key->security = cred->security;
e114e473
CS
2586 return 0;
2587}
2588
2589/**
2590 * smack_key_free - Clear the key security blob
2591 * @key: the object
2592 *
2593 * Clear the blob pointer
2594 */
2595static void smack_key_free(struct key *key)
2596{
2597 key->security = NULL;
2598}
2599
2600/*
2601 * smack_key_permission - Smack access on a key
2602 * @key_ref: gets to the object
d84f4f99 2603 * @cred: the credentials to use
e114e473
CS
2604 * @perm: unused
2605 *
2606 * Return 0 if the task has read and write to the object,
2607 * an error code otherwise
2608 */
2609static int smack_key_permission(key_ref_t key_ref,
d84f4f99 2610 const struct cred *cred, key_perm_t perm)
e114e473
CS
2611{
2612 struct key *keyp;
2613
2614 keyp = key_ref_to_ptr(key_ref);
2615 if (keyp == NULL)
2616 return -EINVAL;
2617 /*
2618 * If the key hasn't been initialized give it access so that
2619 * it may do so.
2620 */
2621 if (keyp->security == NULL)
2622 return 0;
2623 /*
2624 * This should not occur
2625 */
d84f4f99 2626 if (cred->security == NULL)
e114e473
CS
2627 return -EACCES;
2628
d84f4f99 2629 return smk_access(cred->security, keyp->security, MAY_READWRITE);
e114e473
CS
2630}
2631#endif /* CONFIG_KEYS */
2632
d20bdda6
AD
2633/*
2634 * Smack Audit hooks
2635 *
2636 * Audit requires a unique representation of each Smack specific
2637 * rule. This unique representation is used to distinguish the
2638 * object to be audited from remaining kernel objects and also
2639 * works as a glue between the audit hooks.
2640 *
2641 * Since repository entries are added but never deleted, we'll use
2642 * the smack_known label address related to the given audit rule as
2643 * the needed unique representation. This also better fits the smack
2644 * model where nearly everything is a label.
2645 */
2646#ifdef CONFIG_AUDIT
2647
2648/**
2649 * smack_audit_rule_init - Initialize a smack audit rule
2650 * @field: audit rule fields given from user-space (audit.h)
2651 * @op: required testing operator (=, !=, >, <, ...)
2652 * @rulestr: smack label to be audited
2653 * @vrule: pointer to save our own audit rule representation
2654 *
2655 * Prepare to audit cases where (@field @op @rulestr) is true.
2656 * The label to be audited is created if necessay.
2657 */
2658static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2659{
2660 char **rule = (char **)vrule;
2661 *rule = NULL;
2662
2663 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2664 return -EINVAL;
2665
5af75d8d 2666 if (op != Audit_equal && op != Audit_not_equal)
d20bdda6
AD
2667 return -EINVAL;
2668
2669 *rule = smk_import(rulestr, 0);
2670
2671 return 0;
2672}
2673
2674/**
2675 * smack_audit_rule_known - Distinguish Smack audit rules
2676 * @krule: rule of interest, in Audit kernel representation format
2677 *
2678 * This is used to filter Smack rules from remaining Audit ones.
2679 * If it's proved that this rule belongs to us, the
2680 * audit_rule_match hook will be called to do the final judgement.
2681 */
2682static int smack_audit_rule_known(struct audit_krule *krule)
2683{
2684 struct audit_field *f;
2685 int i;
2686
2687 for (i = 0; i < krule->field_count; i++) {
2688 f = &krule->fields[i];
2689
2690 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
2691 return 1;
2692 }
2693
2694 return 0;
2695}
2696
2697/**
2698 * smack_audit_rule_match - Audit given object ?
2699 * @secid: security id for identifying the object to test
2700 * @field: audit rule flags given from user-space
2701 * @op: required testing operator
2702 * @vrule: smack internal rule presentation
2703 * @actx: audit context associated with the check
2704 *
2705 * The core Audit hook. It's used to take the decision of
2706 * whether to audit or not to audit a given object.
2707 */
2708static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
2709 struct audit_context *actx)
2710{
2711 char *smack;
2712 char *rule = vrule;
2713
2714 if (!rule) {
2715 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
2716 "Smack: missing rule\n");
2717 return -ENOENT;
2718 }
2719
2720 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2721 return 0;
2722
2723 smack = smack_from_secid(secid);
2724
2725 /*
2726 * No need to do string comparisons. If a match occurs,
2727 * both pointers will point to the same smack_known
2728 * label.
2729 */
5af75d8d 2730 if (op == Audit_equal)
d20bdda6 2731 return (rule == smack);
5af75d8d 2732 if (op == Audit_not_equal)
d20bdda6
AD
2733 return (rule != smack);
2734
2735 return 0;
2736}
2737
2738/**
2739 * smack_audit_rule_free - free smack rule representation
2740 * @vrule: rule to be freed.
2741 *
2742 * No memory was allocated.
2743 */
2744static void smack_audit_rule_free(void *vrule)
2745{
2746 /* No-op */
2747}
2748
2749#endif /* CONFIG_AUDIT */
2750
251a2a95 2751/**
e114e473
CS
2752 * smack_secid_to_secctx - return the smack label for a secid
2753 * @secid: incoming integer
2754 * @secdata: destination
2755 * @seclen: how long it is
2756 *
2757 * Exists for networking code.
2758 */
2759static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
2760{
2761 char *sp = smack_from_secid(secid);
2762
2763 *secdata = sp;
2764 *seclen = strlen(sp);
2765 return 0;
2766}
2767
251a2a95 2768/**
4bc87e62
CS
2769 * smack_secctx_to_secid - return the secid for a smack label
2770 * @secdata: smack label
2771 * @seclen: how long result is
2772 * @secid: outgoing integer
2773 *
2774 * Exists for audit and networking code.
2775 */
e52c1764 2776static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4bc87e62
CS
2777{
2778 *secid = smack_to_secid(secdata);
2779 return 0;
2780}
2781
251a2a95 2782/**
e114e473 2783 * smack_release_secctx - don't do anything.
251a2a95
RD
2784 * @secdata: unused
2785 * @seclen: unused
e114e473
CS
2786 *
2787 * Exists to make sure nothing gets done, and properly
2788 */
2789static void smack_release_secctx(char *secdata, u32 seclen)
2790{
2791}
2792
076c54c5
AD
2793struct security_operations smack_ops = {
2794 .name = "smack",
2795
5cd9c58f
DH
2796 .ptrace_may_access = smack_ptrace_may_access,
2797 .ptrace_traceme = smack_ptrace_traceme,
e114e473 2798 .capget = cap_capget,
d84f4f99 2799 .capset = cap_capset,
e114e473
CS
2800 .capable = cap_capable,
2801 .syslog = smack_syslog,
2802 .settime = cap_settime,
2803 .vm_enough_memory = cap_vm_enough_memory,
2804
a6f76f23 2805 .bprm_set_creds = cap_bprm_set_creds,
e114e473
CS
2806 .bprm_secureexec = cap_bprm_secureexec,
2807
2808 .sb_alloc_security = smack_sb_alloc_security,
2809 .sb_free_security = smack_sb_free_security,
2810 .sb_copy_data = smack_sb_copy_data,
2811 .sb_kern_mount = smack_sb_kern_mount,
2812 .sb_statfs = smack_sb_statfs,
2813 .sb_mount = smack_sb_mount,
2814 .sb_umount = smack_sb_umount,
2815
2816 .inode_alloc_security = smack_inode_alloc_security,
2817 .inode_free_security = smack_inode_free_security,
2818 .inode_init_security = smack_inode_init_security,
2819 .inode_link = smack_inode_link,
2820 .inode_unlink = smack_inode_unlink,
2821 .inode_rmdir = smack_inode_rmdir,
2822 .inode_rename = smack_inode_rename,
2823 .inode_permission = smack_inode_permission,
2824 .inode_setattr = smack_inode_setattr,
2825 .inode_getattr = smack_inode_getattr,
2826 .inode_setxattr = smack_inode_setxattr,
2827 .inode_post_setxattr = smack_inode_post_setxattr,
2828 .inode_getxattr = smack_inode_getxattr,
2829 .inode_removexattr = smack_inode_removexattr,
bcdca225
CS
2830 .inode_need_killpriv = cap_inode_need_killpriv,
2831 .inode_killpriv = cap_inode_killpriv,
e114e473
CS
2832 .inode_getsecurity = smack_inode_getsecurity,
2833 .inode_setsecurity = smack_inode_setsecurity,
2834 .inode_listsecurity = smack_inode_listsecurity,
d20bdda6 2835 .inode_getsecid = smack_inode_getsecid,
e114e473
CS
2836
2837 .file_permission = smack_file_permission,
2838 .file_alloc_security = smack_file_alloc_security,
2839 .file_free_security = smack_file_free_security,
2840 .file_ioctl = smack_file_ioctl,
2841 .file_lock = smack_file_lock,
2842 .file_fcntl = smack_file_fcntl,
2843 .file_set_fowner = smack_file_set_fowner,
2844 .file_send_sigiotask = smack_file_send_sigiotask,
2845 .file_receive = smack_file_receive,
2846
f1752eec 2847 .cred_free = smack_cred_free,
d84f4f99
DH
2848 .cred_prepare = smack_cred_prepare,
2849 .cred_commit = smack_cred_commit,
3a3b7ce9
DH
2850 .kernel_act_as = smack_kernel_act_as,
2851 .kernel_create_files_as = smack_kernel_create_files_as,
d84f4f99 2852 .task_fix_setuid = cap_task_fix_setuid,
e114e473
CS
2853 .task_setpgid = smack_task_setpgid,
2854 .task_getpgid = smack_task_getpgid,
2855 .task_getsid = smack_task_getsid,
2856 .task_getsecid = smack_task_getsecid,
2857 .task_setnice = smack_task_setnice,
2858 .task_setioprio = smack_task_setioprio,
2859 .task_getioprio = smack_task_getioprio,
2860 .task_setscheduler = smack_task_setscheduler,
2861 .task_getscheduler = smack_task_getscheduler,
2862 .task_movememory = smack_task_movememory,
2863 .task_kill = smack_task_kill,
2864 .task_wait = smack_task_wait,
e114e473 2865 .task_to_inode = smack_task_to_inode,
1236cc3c 2866 .task_prctl = cap_task_prctl,
e114e473
CS
2867
2868 .ipc_permission = smack_ipc_permission,
d20bdda6 2869 .ipc_getsecid = smack_ipc_getsecid,
e114e473
CS
2870
2871 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
2872 .msg_msg_free_security = smack_msg_msg_free_security,
2873
2874 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
2875 .msg_queue_free_security = smack_msg_queue_free_security,
2876 .msg_queue_associate = smack_msg_queue_associate,
2877 .msg_queue_msgctl = smack_msg_queue_msgctl,
2878 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
2879 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
2880
2881 .shm_alloc_security = smack_shm_alloc_security,
2882 .shm_free_security = smack_shm_free_security,
2883 .shm_associate = smack_shm_associate,
2884 .shm_shmctl = smack_shm_shmctl,
2885 .shm_shmat = smack_shm_shmat,
2886
2887 .sem_alloc_security = smack_sem_alloc_security,
2888 .sem_free_security = smack_sem_free_security,
2889 .sem_associate = smack_sem_associate,
2890 .sem_semctl = smack_sem_semctl,
2891 .sem_semop = smack_sem_semop,
2892
2893 .netlink_send = cap_netlink_send,
2894 .netlink_recv = cap_netlink_recv,
2895
2896 .d_instantiate = smack_d_instantiate,
2897
2898 .getprocattr = smack_getprocattr,
2899 .setprocattr = smack_setprocattr,
2900
2901 .unix_stream_connect = smack_unix_stream_connect,
2902 .unix_may_send = smack_unix_may_send,
2903
2904 .socket_post_create = smack_socket_post_create,
6d3dc07c
CS
2905 .socket_connect = smack_socket_connect,
2906 .socket_sendmsg = smack_socket_sendmsg,
e114e473
CS
2907 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
2908 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
2909 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
2910 .sk_alloc_security = smack_sk_alloc_security,
2911 .sk_free_security = smack_sk_free_security,
2912 .sock_graft = smack_sock_graft,
2913 .inet_conn_request = smack_inet_conn_request,
d20bdda6 2914
e114e473
CS
2915 /* key management security hooks */
2916#ifdef CONFIG_KEYS
2917 .key_alloc = smack_key_alloc,
2918 .key_free = smack_key_free,
2919 .key_permission = smack_key_permission,
2920#endif /* CONFIG_KEYS */
d20bdda6
AD
2921
2922 /* Audit hooks */
2923#ifdef CONFIG_AUDIT
2924 .audit_rule_init = smack_audit_rule_init,
2925 .audit_rule_known = smack_audit_rule_known,
2926 .audit_rule_match = smack_audit_rule_match,
2927 .audit_rule_free = smack_audit_rule_free,
2928#endif /* CONFIG_AUDIT */
2929
e114e473 2930 .secid_to_secctx = smack_secid_to_secctx,
4bc87e62 2931 .secctx_to_secid = smack_secctx_to_secid,
e114e473
CS
2932 .release_secctx = smack_release_secctx,
2933};
2934
7198e2ee
EB
2935
2936static __init void init_smack_know_list(void)
2937{
2938 list_add(&smack_known_huh.list, &smack_known_list);
2939 list_add(&smack_known_hat.list, &smack_known_list);
2940 list_add(&smack_known_star.list, &smack_known_list);
2941 list_add(&smack_known_floor.list, &smack_known_list);
2942 list_add(&smack_known_invalid.list, &smack_known_list);
2943 list_add(&smack_known_web.list, &smack_known_list);
2944}
2945
e114e473
CS
2946/**
2947 * smack_init - initialize the smack system
2948 *
2949 * Returns 0
2950 */
2951static __init int smack_init(void)
2952{
d84f4f99
DH
2953 struct cred *cred;
2954
076c54c5
AD
2955 if (!security_module_enable(&smack_ops))
2956 return 0;
2957
e114e473
CS
2958 printk(KERN_INFO "Smack: Initializing.\n");
2959
2960 /*
2961 * Set the security state for the initial task.
2962 */
d84f4f99
DH
2963 cred = (struct cred *) current->cred;
2964 cred->security = &smack_known_floor.smk_known;
e114e473 2965
7198e2ee
EB
2966 /* initilize the smack_know_list */
2967 init_smack_know_list();
e114e473
CS
2968 /*
2969 * Initialize locks
2970 */
e114e473
CS
2971 spin_lock_init(&smack_known_huh.smk_cipsolock);
2972 spin_lock_init(&smack_known_hat.smk_cipsolock);
2973 spin_lock_init(&smack_known_star.smk_cipsolock);
2974 spin_lock_init(&smack_known_floor.smk_cipsolock);
2975 spin_lock_init(&smack_known_invalid.smk_cipsolock);
2976
2977 /*
2978 * Register with LSM
2979 */
2980 if (register_security(&smack_ops))
2981 panic("smack: Unable to register with kernel.\n");
2982
2983 return 0;
2984}
2985
2986/*
2987 * Smack requires early initialization in order to label
2988 * all processes and objects when they are created.
2989 */
2990security_initcall(smack_init);