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clean up audit_rule_{add,del} a bit
[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>
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30
31#include "smack.h"
32
c69e8d9c
DH
33#define task_security(task) (task_cred_xxx((task), security))
34
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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
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93 * @ctp: child task pointer
94 *
95 * Returns 0 if access is OK, an error code otherwise
96 *
97 * Do the capability checks, and require read and write.
98 */
5cd9c58f 99static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode)
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CS
100{
101 int rc;
102
5cd9c58f 103 rc = cap_ptrace_may_access(ctp, mode);
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104 if (rc != 0)
105 return rc;
106
d84f4f99 107 rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE);
5cd9c58f 108 if (rc != 0 && capable(CAP_MAC_OVERRIDE))
e114e473 109 return 0;
5cd9c58f
DH
110 return rc;
111}
112
113/**
114 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
115 * @ptp: parent task pointer
116 *
117 * Returns 0 if access is OK, an error code otherwise
118 *
119 * Do the capability checks, and require read and write.
120 */
121static int smack_ptrace_traceme(struct task_struct *ptp)
122{
123 int rc;
124
125 rc = cap_ptrace_traceme(ptp);
126 if (rc != 0)
127 return rc;
e114e473 128
d84f4f99 129 rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE);
5cd9c58f
DH
130 if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE))
131 return 0;
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132 return rc;
133}
134
135/**
136 * smack_syslog - Smack approval on syslog
137 * @type: message type
138 *
139 * Require that the task has the floor label
140 *
141 * Returns 0 on success, error code otherwise.
142 */
143static int smack_syslog(int type)
144{
145 int rc;
86a264ab 146 char *sp = current_security();
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CS
147
148 rc = cap_syslog(type);
149 if (rc != 0)
150 return rc;
151
152 if (capable(CAP_MAC_OVERRIDE))
153 return 0;
154
155 if (sp != smack_known_floor.smk_known)
156 rc = -EACCES;
157
158 return rc;
159}
160
161
162/*
163 * Superblock Hooks.
164 */
165
166/**
167 * smack_sb_alloc_security - allocate a superblock blob
168 * @sb: the superblock getting the blob
169 *
170 * Returns 0 on success or -ENOMEM on error.
171 */
172static int smack_sb_alloc_security(struct super_block *sb)
173{
174 struct superblock_smack *sbsp;
175
176 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
177
178 if (sbsp == NULL)
179 return -ENOMEM;
180
181 sbsp->smk_root = smack_known_floor.smk_known;
182 sbsp->smk_default = smack_known_floor.smk_known;
183 sbsp->smk_floor = smack_known_floor.smk_known;
184 sbsp->smk_hat = smack_known_hat.smk_known;
185 sbsp->smk_initialized = 0;
186 spin_lock_init(&sbsp->smk_sblock);
187
188 sb->s_security = sbsp;
189
190 return 0;
191}
192
193/**
194 * smack_sb_free_security - free a superblock blob
195 * @sb: the superblock getting the blob
196 *
197 */
198static void smack_sb_free_security(struct super_block *sb)
199{
200 kfree(sb->s_security);
201 sb->s_security = NULL;
202}
203
204/**
205 * smack_sb_copy_data - copy mount options data for processing
206 * @type: file system type
207 * @orig: where to start
208 * @smackopts
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)
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CS
216{
217 char *cp, *commap, *otheropts, *dp;
218
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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
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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
334 * @nd: mount point
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
373 * @inode - the inode in need of a blob
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
387 * @inode - the inode with a blob
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
541 * @nd: unused
542 *
543 * This is the important Smack hook.
544 *
545 * Returns 0 if access is permitted, -EACCES otherwise
546 */
b77b0646 547static int smack_inode_permission(struct inode *inode, int mask)
e114e473
CS
548{
549 /*
550 * No permission to check. Existence test. Yup, it's there.
551 */
552 if (mask == 0)
553 return 0;
554
555 return smk_curacc(smk_of_inode(inode), mask);
556}
557
558/**
559 * smack_inode_setattr - Smack check for setting attributes
560 * @dentry: the object
561 * @iattr: for the force flag
562 *
563 * Returns 0 if access is permitted, an error code otherwise
564 */
565static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
566{
567 /*
568 * Need to allow for clearing the setuid bit.
569 */
570 if (iattr->ia_valid & ATTR_FORCE)
571 return 0;
572
573 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
574}
575
576/**
577 * smack_inode_getattr - Smack check for getting attributes
578 * @mnt: unused
579 * @dentry: the object
580 *
581 * Returns 0 if access is permitted, an error code otherwise
582 */
583static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
584{
585 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
586}
587
588/**
589 * smack_inode_setxattr - Smack check for setting xattrs
590 * @dentry: the object
591 * @name: name of the attribute
592 * @value: unused
593 * @size: unused
594 * @flags: unused
595 *
596 * This protects the Smack attribute explicitly.
597 *
598 * Returns 0 if access is permitted, an error code otherwise
599 */
8f0cfa52
DH
600static int smack_inode_setxattr(struct dentry *dentry, const char *name,
601 const void *value, size_t size, int flags)
e114e473 602{
bcdca225 603 int rc = 0;
e114e473 604
bcdca225
CS
605 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
606 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
607 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
608 if (!capable(CAP_MAC_ADMIN))
609 rc = -EPERM;
610 } else
611 rc = cap_inode_setxattr(dentry, name, value, size, flags);
612
613 if (rc == 0)
614 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
615
616 return rc;
e114e473
CS
617}
618
619/**
620 * smack_inode_post_setxattr - Apply the Smack update approved above
621 * @dentry: object
622 * @name: attribute name
623 * @value: attribute value
624 * @size: attribute size
625 * @flags: unused
626 *
627 * Set the pointer in the inode blob to the entry found
628 * in the master label list.
629 */
8f0cfa52
DH
630static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
631 const void *value, size_t size, int flags)
e114e473
CS
632{
633 struct inode_smack *isp;
634 char *nsp;
635
636 /*
637 * Not SMACK
638 */
639 if (strcmp(name, XATTR_NAME_SMACK))
640 return;
641
642 if (size >= SMK_LABELLEN)
643 return;
644
645 isp = dentry->d_inode->i_security;
646
647 /*
648 * No locking is done here. This is a pointer
649 * assignment.
650 */
651 nsp = smk_import(value, size);
652 if (nsp != NULL)
653 isp->smk_inode = nsp;
654 else
655 isp->smk_inode = smack_known_invalid.smk_known;
656
657 return;
658}
659
660/*
661 * smack_inode_getxattr - Smack check on getxattr
662 * @dentry: the object
663 * @name: unused
664 *
665 * Returns 0 if access is permitted, an error code otherwise
666 */
8f0cfa52 667static int smack_inode_getxattr(struct dentry *dentry, const char *name)
e114e473
CS
668{
669 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
670}
671
672/*
673 * smack_inode_removexattr - Smack check on removexattr
674 * @dentry: the object
675 * @name: name of the attribute
676 *
677 * Removing the Smack attribute requires CAP_MAC_ADMIN
678 *
679 * Returns 0 if access is permitted, an error code otherwise
680 */
8f0cfa52 681static int smack_inode_removexattr(struct dentry *dentry, const char *name)
e114e473 682{
bcdca225 683 int rc = 0;
e114e473 684
bcdca225
CS
685 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
686 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
687 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
688 if (!capable(CAP_MAC_ADMIN))
689 rc = -EPERM;
690 } else
691 rc = cap_inode_removexattr(dentry, name);
692
693 if (rc == 0)
694 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
695
696 return rc;
e114e473
CS
697}
698
699/**
700 * smack_inode_getsecurity - get smack xattrs
701 * @inode: the object
702 * @name: attribute name
703 * @buffer: where to put the result
704 * @size: size of the buffer
705 * @err: unused
706 *
707 * Returns the size of the attribute or an error code
708 */
709static int smack_inode_getsecurity(const struct inode *inode,
710 const char *name, void **buffer,
711 bool alloc)
712{
713 struct socket_smack *ssp;
714 struct socket *sock;
715 struct super_block *sbp;
716 struct inode *ip = (struct inode *)inode;
717 char *isp;
718 int ilen;
719 int rc = 0;
720
721 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
722 isp = smk_of_inode(inode);
723 ilen = strlen(isp) + 1;
724 *buffer = isp;
725 return ilen;
726 }
727
728 /*
729 * The rest of the Smack xattrs are only on sockets.
730 */
731 sbp = ip->i_sb;
732 if (sbp->s_magic != SOCKFS_MAGIC)
733 return -EOPNOTSUPP;
734
735 sock = SOCKET_I(ip);
2e1d146a 736 if (sock == NULL || sock->sk == NULL)
e114e473
CS
737 return -EOPNOTSUPP;
738
739 ssp = sock->sk->sk_security;
740
741 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
742 isp = ssp->smk_in;
743 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
744 isp = ssp->smk_out;
745 else
746 return -EOPNOTSUPP;
747
748 ilen = strlen(isp) + 1;
749 if (rc == 0) {
750 *buffer = isp;
751 rc = ilen;
752 }
753
754 return rc;
755}
756
757
758/**
759 * smack_inode_listsecurity - list the Smack attributes
760 * @inode: the object
761 * @buffer: where they go
762 * @buffer_size: size of buffer
763 *
764 * Returns 0 on success, -EINVAL otherwise
765 */
766static int smack_inode_listsecurity(struct inode *inode, char *buffer,
767 size_t buffer_size)
768{
769 int len = strlen(XATTR_NAME_SMACK);
770
771 if (buffer != NULL && len <= buffer_size) {
772 memcpy(buffer, XATTR_NAME_SMACK, len);
773 return len;
774 }
775 return -EINVAL;
776}
777
d20bdda6
AD
778/**
779 * smack_inode_getsecid - Extract inode's security id
780 * @inode: inode to extract the info from
781 * @secid: where result will be saved
782 */
783static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
784{
785 struct inode_smack *isp = inode->i_security;
786
787 *secid = smack_to_secid(isp->smk_inode);
788}
789
e114e473
CS
790/*
791 * File Hooks
792 */
793
794/**
795 * smack_file_permission - Smack check on file operations
796 * @file: unused
797 * @mask: unused
798 *
799 * Returns 0
800 *
801 * Should access checks be done on each read or write?
802 * UNICOS and SELinux say yes.
803 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
804 *
805 * I'll say no for now. Smack does not do the frequent
806 * label changing that SELinux does.
807 */
808static int smack_file_permission(struct file *file, int mask)
809{
810 return 0;
811}
812
813/**
814 * smack_file_alloc_security - assign a file security blob
815 * @file: the object
816 *
817 * The security blob for a file is a pointer to the master
818 * label list, so no allocation is done.
819 *
820 * Returns 0
821 */
822static int smack_file_alloc_security(struct file *file)
823{
86a264ab 824 file->f_security = current_security();
e114e473
CS
825 return 0;
826}
827
828/**
829 * smack_file_free_security - clear a file security blob
830 * @file: the object
831 *
832 * The security blob for a file is a pointer to the master
833 * label list, so no memory is freed.
834 */
835static void smack_file_free_security(struct file *file)
836{
837 file->f_security = NULL;
838}
839
840/**
841 * smack_file_ioctl - Smack check on ioctls
842 * @file: the object
843 * @cmd: what to do
844 * @arg: unused
845 *
846 * Relies heavily on the correct use of the ioctl command conventions.
847 *
848 * Returns 0 if allowed, error code otherwise
849 */
850static int smack_file_ioctl(struct file *file, unsigned int cmd,
851 unsigned long arg)
852{
853 int rc = 0;
854
855 if (_IOC_DIR(cmd) & _IOC_WRITE)
856 rc = smk_curacc(file->f_security, MAY_WRITE);
857
858 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
859 rc = smk_curacc(file->f_security, MAY_READ);
860
861 return rc;
862}
863
864/**
865 * smack_file_lock - Smack check on file locking
866 * @file: the object
867 * @cmd unused
868 *
869 * Returns 0 if current has write access, error code otherwise
870 */
871static int smack_file_lock(struct file *file, unsigned int cmd)
872{
873 return smk_curacc(file->f_security, MAY_WRITE);
874}
875
876/**
877 * smack_file_fcntl - Smack check on fcntl
878 * @file: the object
879 * @cmd: what action to check
880 * @arg: unused
881 *
882 * Returns 0 if current has access, error code otherwise
883 */
884static int smack_file_fcntl(struct file *file, unsigned int cmd,
885 unsigned long arg)
886{
887 int rc;
888
889 switch (cmd) {
890 case F_DUPFD:
891 case F_GETFD:
892 case F_GETFL:
893 case F_GETLK:
894 case F_GETOWN:
895 case F_GETSIG:
896 rc = smk_curacc(file->f_security, MAY_READ);
897 break;
898 case F_SETFD:
899 case F_SETFL:
900 case F_SETLK:
901 case F_SETLKW:
902 case F_SETOWN:
903 case F_SETSIG:
904 rc = smk_curacc(file->f_security, MAY_WRITE);
905 break;
906 default:
907 rc = smk_curacc(file->f_security, MAY_READWRITE);
908 }
909
910 return rc;
911}
912
913/**
914 * smack_file_set_fowner - set the file security blob value
915 * @file: object in question
916 *
917 * Returns 0
918 * Further research may be required on this one.
919 */
920static int smack_file_set_fowner(struct file *file)
921{
86a264ab 922 file->f_security = current_security();
e114e473
CS
923 return 0;
924}
925
926/**
927 * smack_file_send_sigiotask - Smack on sigio
928 * @tsk: The target task
929 * @fown: the object the signal come from
930 * @signum: unused
931 *
932 * Allow a privileged task to get signals even if it shouldn't
933 *
934 * Returns 0 if a subject with the object's smack could
935 * write to the task, an error code otherwise.
936 */
937static int smack_file_send_sigiotask(struct task_struct *tsk,
938 struct fown_struct *fown, int signum)
939{
940 struct file *file;
941 int rc;
942
943 /*
944 * struct fown_struct is never outside the context of a struct file
945 */
946 file = container_of(fown, struct file, f_owner);
b6dff3ec 947 rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE);
5cd9c58f 948 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
e114e473
CS
949 return 0;
950 return rc;
951}
952
953/**
954 * smack_file_receive - Smack file receive check
955 * @file: the object
956 *
957 * Returns 0 if current has access, error code otherwise
958 */
959static int smack_file_receive(struct file *file)
960{
961 int may = 0;
962
963 /*
964 * This code relies on bitmasks.
965 */
966 if (file->f_mode & FMODE_READ)
967 may = MAY_READ;
968 if (file->f_mode & FMODE_WRITE)
969 may |= MAY_WRITE;
970
971 return smk_curacc(file->f_security, may);
972}
973
974/*
975 * Task hooks
976 */
977
e114e473 978/**
f1752eec
DH
979 * smack_cred_free - "free" task-level security credentials
980 * @cred: the credentials in question
e114e473
CS
981 *
982 * Smack isn't using copies of blobs. Everyone
983 * points to an immutable list. The blobs never go away.
984 * There is no leak here.
985 */
f1752eec 986static void smack_cred_free(struct cred *cred)
e114e473 987{
f1752eec 988 cred->security = NULL;
e114e473
CS
989}
990
d84f4f99
DH
991/**
992 * smack_cred_prepare - prepare new set of credentials for modification
993 * @new: the new credentials
994 * @old: the original credentials
995 * @gfp: the atomicity of any memory allocations
996 *
997 * Prepare a new set of credentials for modification.
998 */
999static int smack_cred_prepare(struct cred *new, const struct cred *old,
1000 gfp_t gfp)
1001{
1002 new->security = old->security;
1003 return 0;
1004}
1005
1006/*
1007 * commit new credentials
1008 * @new: the new credentials
1009 * @old: the original credentials
1010 */
1011static void smack_cred_commit(struct cred *new, const struct cred *old)
1012{
1013}
1014
3a3b7ce9
DH
1015/**
1016 * smack_kernel_act_as - Set the subjective context in a set of credentials
1017 * @new points to the set of credentials to be modified.
1018 * @secid specifies the security ID to be set
1019 *
1020 * Set the security data for a kernel service.
1021 */
1022static int smack_kernel_act_as(struct cred *new, u32 secid)
1023{
1024 char *smack = smack_from_secid(secid);
1025
1026 if (smack == NULL)
1027 return -EINVAL;
1028
1029 new->security = smack;
1030 return 0;
1031}
1032
1033/**
1034 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1035 * @new points to the set of credentials to be modified
1036 * @inode points to the inode to use as a reference
1037 *
1038 * Set the file creation context in a set of credentials to the same
1039 * as the objective context of the specified inode
1040 */
1041static int smack_kernel_create_files_as(struct cred *new,
1042 struct inode *inode)
1043{
1044 struct inode_smack *isp = inode->i_security;
1045
1046 new->security = isp->smk_inode;
1047 return 0;
1048}
1049
e114e473
CS
1050/**
1051 * smack_task_setpgid - Smack check on setting pgid
1052 * @p: the task object
1053 * @pgid: unused
1054 *
1055 * Return 0 if write access is permitted
1056 */
1057static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1058{
c69e8d9c 1059 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1060}
1061
1062/**
1063 * smack_task_getpgid - Smack access check for getpgid
1064 * @p: the object task
1065 *
1066 * Returns 0 if current can read the object task, error code otherwise
1067 */
1068static int smack_task_getpgid(struct task_struct *p)
1069{
c69e8d9c 1070 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1071}
1072
1073/**
1074 * smack_task_getsid - Smack access check for getsid
1075 * @p: the object task
1076 *
1077 * Returns 0 if current can read the object task, error code otherwise
1078 */
1079static int smack_task_getsid(struct task_struct *p)
1080{
c69e8d9c 1081 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1082}
1083
1084/**
1085 * smack_task_getsecid - get the secid of the task
1086 * @p: the object task
1087 * @secid: where to put the result
1088 *
1089 * Sets the secid to contain a u32 version of the smack label.
1090 */
1091static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1092{
c69e8d9c 1093 *secid = smack_to_secid(task_security(p));
e114e473
CS
1094}
1095
1096/**
1097 * smack_task_setnice - Smack check on setting nice
1098 * @p: the task object
1099 * @nice: unused
1100 *
1101 * Return 0 if write access is permitted
1102 */
1103static int smack_task_setnice(struct task_struct *p, int nice)
1104{
bcdca225
CS
1105 int rc;
1106
1107 rc = cap_task_setnice(p, nice);
1108 if (rc == 0)
c69e8d9c 1109 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1110 return rc;
e114e473
CS
1111}
1112
1113/**
1114 * smack_task_setioprio - Smack check on setting ioprio
1115 * @p: the task object
1116 * @ioprio: unused
1117 *
1118 * Return 0 if write access is permitted
1119 */
1120static int smack_task_setioprio(struct task_struct *p, int ioprio)
1121{
bcdca225
CS
1122 int rc;
1123
1124 rc = cap_task_setioprio(p, ioprio);
1125 if (rc == 0)
c69e8d9c 1126 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1127 return rc;
e114e473
CS
1128}
1129
1130/**
1131 * smack_task_getioprio - Smack check on reading ioprio
1132 * @p: the task object
1133 *
1134 * Return 0 if read access is permitted
1135 */
1136static int smack_task_getioprio(struct task_struct *p)
1137{
c69e8d9c 1138 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1139}
1140
1141/**
1142 * smack_task_setscheduler - Smack check on setting scheduler
1143 * @p: the task object
1144 * @policy: unused
1145 * @lp: unused
1146 *
1147 * Return 0 if read access is permitted
1148 */
1149static int smack_task_setscheduler(struct task_struct *p, int policy,
1150 struct sched_param *lp)
1151{
bcdca225
CS
1152 int rc;
1153
1154 rc = cap_task_setscheduler(p, policy, lp);
1155 if (rc == 0)
c69e8d9c 1156 rc = smk_curacc(task_security(p), MAY_WRITE);
bcdca225 1157 return rc;
e114e473
CS
1158}
1159
1160/**
1161 * smack_task_getscheduler - Smack check on reading scheduler
1162 * @p: the task object
1163 *
1164 * Return 0 if read access is permitted
1165 */
1166static int smack_task_getscheduler(struct task_struct *p)
1167{
c69e8d9c 1168 return smk_curacc(task_security(p), MAY_READ);
e114e473
CS
1169}
1170
1171/**
1172 * smack_task_movememory - Smack check on moving memory
1173 * @p: the task object
1174 *
1175 * Return 0 if write access is permitted
1176 */
1177static int smack_task_movememory(struct task_struct *p)
1178{
c69e8d9c 1179 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1180}
1181
1182/**
1183 * smack_task_kill - Smack check on signal delivery
1184 * @p: the task object
1185 * @info: unused
1186 * @sig: unused
1187 * @secid: identifies the smack to use in lieu of current's
1188 *
1189 * Return 0 if write access is permitted
1190 *
1191 * The secid behavior is an artifact of an SELinux hack
1192 * in the USB code. Someday it may go away.
1193 */
1194static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1195 int sig, u32 secid)
1196{
e114e473
CS
1197 /*
1198 * Sending a signal requires that the sender
1199 * can write the receiver.
1200 */
1201 if (secid == 0)
c69e8d9c 1202 return smk_curacc(task_security(p), MAY_WRITE);
e114e473
CS
1203 /*
1204 * If the secid isn't 0 we're dealing with some USB IO
1205 * specific behavior. This is not clean. For one thing
1206 * we can't take privilege into account.
1207 */
c69e8d9c 1208 return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE);
e114e473
CS
1209}
1210
1211/**
1212 * smack_task_wait - Smack access check for waiting
1213 * @p: task to wait for
1214 *
1215 * Returns 0 if current can wait for p, error code otherwise
1216 */
1217static int smack_task_wait(struct task_struct *p)
1218{
1219 int rc;
1220
c69e8d9c 1221 rc = smk_access(current_security(), task_security(p), MAY_WRITE);
e114e473
CS
1222 if (rc == 0)
1223 return 0;
1224
1225 /*
1226 * Allow the operation to succeed if either task
1227 * has privilege to perform operations that might
1228 * account for the smack labels having gotten to
1229 * be different in the first place.
1230 *
5cd9c58f 1231 * This breaks the strict subject/object access
e114e473
CS
1232 * control ideal, taking the object's privilege
1233 * state into account in the decision as well as
1234 * the smack value.
1235 */
5cd9c58f 1236 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
e114e473
CS
1237 return 0;
1238
1239 return rc;
1240}
1241
1242/**
1243 * smack_task_to_inode - copy task smack into the inode blob
1244 * @p: task to copy from
1245 * inode: inode to copy to
1246 *
1247 * Sets the smack pointer in the inode security blob
1248 */
1249static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1250{
1251 struct inode_smack *isp = inode->i_security;
c69e8d9c 1252 isp->smk_inode = task_security(p);
e114e473
CS
1253}
1254
1255/*
1256 * Socket hooks.
1257 */
1258
1259/**
1260 * smack_sk_alloc_security - Allocate a socket blob
1261 * @sk: the socket
1262 * @family: unused
1263 * @priority: memory allocation priority
1264 *
1265 * Assign Smack pointers to current
1266 *
1267 * Returns 0 on success, -ENOMEM is there's no memory
1268 */
1269static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1270{
86a264ab 1271 char *csp = current_security();
e114e473
CS
1272 struct socket_smack *ssp;
1273
1274 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1275 if (ssp == NULL)
1276 return -ENOMEM;
1277
1278 ssp->smk_in = csp;
1279 ssp->smk_out = csp;
1280 ssp->smk_packet[0] = '\0';
1281
1282 sk->sk_security = ssp;
1283
1284 return 0;
1285}
1286
1287/**
1288 * smack_sk_free_security - Free a socket blob
1289 * @sk: the socket
1290 *
1291 * Clears the blob pointer
1292 */
1293static void smack_sk_free_security(struct sock *sk)
1294{
1295 kfree(sk->sk_security);
1296}
1297
1298/**
1299 * smack_set_catset - convert a capset to netlabel mls categories
1300 * @catset: the Smack categories
1301 * @sap: where to put the netlabel categories
1302 *
1303 * Allocates and fills attr.mls.cat
1304 */
1305static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1306{
1307 unsigned char *cp;
1308 unsigned char m;
1309 int cat;
1310 int rc;
1311 int byte;
1312
c60264c4 1313 if (!catset)
e114e473
CS
1314 return;
1315
1316 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1317 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1318 sap->attr.mls.cat->startbit = 0;
1319
1320 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1321 for (m = 0x80; m != 0; m >>= 1, cat++) {
1322 if ((m & *cp) == 0)
1323 continue;
1324 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1325 cat, GFP_ATOMIC);
1326 }
1327}
1328
1329/**
1330 * smack_to_secattr - fill a secattr from a smack value
1331 * @smack: the smack value
1332 * @nlsp: where the result goes
1333 *
1334 * Casey says that CIPSO is good enough for now.
1335 * It can be used to effect.
1336 * It can also be abused to effect when necessary.
1337 * Appologies to the TSIG group in general and GW in particular.
1338 */
1339static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1340{
1341 struct smack_cipso cipso;
1342 int rc;
1343
1344 switch (smack_net_nltype) {
1345 case NETLBL_NLTYPE_CIPSOV4:
00447872 1346 nlsp->domain = smack;
4bc87e62 1347 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
e114e473
CS
1348
1349 rc = smack_to_cipso(smack, &cipso);
1350 if (rc == 0) {
1351 nlsp->attr.mls.lvl = cipso.smk_level;
1352 smack_set_catset(cipso.smk_catset, nlsp);
1353 } else {
1354 nlsp->attr.mls.lvl = smack_cipso_direct;
1355 smack_set_catset(smack, nlsp);
1356 }
1357 break;
1358 default:
1359 break;
1360 }
1361}
1362
1363/**
1364 * smack_netlabel - Set the secattr on a socket
1365 * @sk: the socket
1366 *
1367 * Convert the outbound smack value (smk_out) to a
1368 * secattr and attach it to the socket.
1369 *
1370 * Returns 0 on success or an error code
1371 */
1372static int smack_netlabel(struct sock *sk)
1373{
2e1d146a 1374 struct socket_smack *ssp;
e114e473 1375 struct netlbl_lsm_secattr secattr;
4bc87e62 1376 int rc;
e114e473 1377
2e1d146a 1378 ssp = sk->sk_security;
e114e473
CS
1379 netlbl_secattr_init(&secattr);
1380 smack_to_secattr(ssp->smk_out, &secattr);
4bc87e62 1381 rc = netlbl_sock_setattr(sk, &secattr);
e114e473 1382 netlbl_secattr_destroy(&secattr);
4bc87e62 1383
e114e473
CS
1384 return rc;
1385}
1386
1387/**
1388 * smack_inode_setsecurity - set smack xattrs
1389 * @inode: the object
1390 * @name: attribute name
1391 * @value: attribute value
1392 * @size: size of the attribute
1393 * @flags: unused
1394 *
1395 * Sets the named attribute in the appropriate blob
1396 *
1397 * Returns 0 on success, or an error code
1398 */
1399static int smack_inode_setsecurity(struct inode *inode, const char *name,
1400 const void *value, size_t size, int flags)
1401{
1402 char *sp;
1403 struct inode_smack *nsp = inode->i_security;
1404 struct socket_smack *ssp;
1405 struct socket *sock;
4bc87e62 1406 int rc = 0;
e114e473
CS
1407
1408 if (value == NULL || size > SMK_LABELLEN)
1409 return -EACCES;
1410
1411 sp = smk_import(value, size);
1412 if (sp == NULL)
1413 return -EINVAL;
1414
1415 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1416 nsp->smk_inode = sp;
1417 return 0;
1418 }
1419 /*
1420 * The rest of the Smack xattrs are only on sockets.
1421 */
1422 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1423 return -EOPNOTSUPP;
1424
1425 sock = SOCKET_I(inode);
2e1d146a 1426 if (sock == NULL || sock->sk == NULL)
e114e473
CS
1427 return -EOPNOTSUPP;
1428
1429 ssp = sock->sk->sk_security;
1430
1431 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1432 ssp->smk_in = sp;
1433 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1434 ssp->smk_out = sp;
4bc87e62
CS
1435 rc = smack_netlabel(sock->sk);
1436 if (rc != 0)
1437 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
1438 __func__, -rc);
e114e473
CS
1439 } else
1440 return -EOPNOTSUPP;
1441
1442 return 0;
1443}
1444
1445/**
1446 * smack_socket_post_create - finish socket setup
1447 * @sock: the socket
1448 * @family: protocol family
1449 * @type: unused
1450 * @protocol: unused
1451 * @kern: unused
1452 *
1453 * Sets the netlabel information on the socket
1454 *
1455 * Returns 0 on success, and error code otherwise
1456 */
1457static int smack_socket_post_create(struct socket *sock, int family,
1458 int type, int protocol, int kern)
1459{
2e1d146a 1460 if (family != PF_INET || sock->sk == NULL)
e114e473
CS
1461 return 0;
1462 /*
1463 * Set the outbound netlbl.
1464 */
1465 return smack_netlabel(sock->sk);
1466}
1467
1468/**
1469 * smack_flags_to_may - convert S_ to MAY_ values
1470 * @flags: the S_ value
1471 *
1472 * Returns the equivalent MAY_ value
1473 */
1474static int smack_flags_to_may(int flags)
1475{
1476 int may = 0;
1477
1478 if (flags & S_IRUGO)
1479 may |= MAY_READ;
1480 if (flags & S_IWUGO)
1481 may |= MAY_WRITE;
1482 if (flags & S_IXUGO)
1483 may |= MAY_EXEC;
1484
1485 return may;
1486}
1487
1488/**
1489 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
1490 * @msg: the object
1491 *
1492 * Returns 0
1493 */
1494static int smack_msg_msg_alloc_security(struct msg_msg *msg)
1495{
86a264ab 1496 msg->security = current_security();
e114e473
CS
1497 return 0;
1498}
1499
1500/**
1501 * smack_msg_msg_free_security - Clear the security blob for msg_msg
1502 * @msg: the object
1503 *
1504 * Clears the blob pointer
1505 */
1506static void smack_msg_msg_free_security(struct msg_msg *msg)
1507{
1508 msg->security = NULL;
1509}
1510
1511/**
1512 * smack_of_shm - the smack pointer for the shm
1513 * @shp: the object
1514 *
1515 * Returns a pointer to the smack value
1516 */
1517static char *smack_of_shm(struct shmid_kernel *shp)
1518{
1519 return (char *)shp->shm_perm.security;
1520}
1521
1522/**
1523 * smack_shm_alloc_security - Set the security blob for shm
1524 * @shp: the object
1525 *
1526 * Returns 0
1527 */
1528static int smack_shm_alloc_security(struct shmid_kernel *shp)
1529{
1530 struct kern_ipc_perm *isp = &shp->shm_perm;
1531
86a264ab 1532 isp->security = current_security();
e114e473
CS
1533 return 0;
1534}
1535
1536/**
1537 * smack_shm_free_security - Clear the security blob for shm
1538 * @shp: the object
1539 *
1540 * Clears the blob pointer
1541 */
1542static void smack_shm_free_security(struct shmid_kernel *shp)
1543{
1544 struct kern_ipc_perm *isp = &shp->shm_perm;
1545
1546 isp->security = NULL;
1547}
1548
1549/**
1550 * smack_shm_associate - Smack access check for shm
1551 * @shp: the object
1552 * @shmflg: access requested
1553 *
1554 * Returns 0 if current has the requested access, error code otherwise
1555 */
1556static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
1557{
1558 char *ssp = smack_of_shm(shp);
1559 int may;
1560
1561 may = smack_flags_to_may(shmflg);
1562 return smk_curacc(ssp, may);
1563}
1564
1565/**
1566 * smack_shm_shmctl - Smack access check for shm
1567 * @shp: the object
1568 * @cmd: what it wants to do
1569 *
1570 * Returns 0 if current has the requested access, error code otherwise
1571 */
1572static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
1573{
1d252fb8 1574 char *ssp;
e114e473
CS
1575 int may;
1576
1577 switch (cmd) {
1578 case IPC_STAT:
1579 case SHM_STAT:
1580 may = MAY_READ;
1581 break;
1582 case IPC_SET:
1583 case SHM_LOCK:
1584 case SHM_UNLOCK:
1585 case IPC_RMID:
1586 may = MAY_READWRITE;
1587 break;
1588 case IPC_INFO:
1589 case SHM_INFO:
1590 /*
1591 * System level information.
1592 */
1593 return 0;
1594 default:
1595 return -EINVAL;
1596 }
1597
1d252fb8 1598 ssp = smack_of_shm(shp);
e114e473
CS
1599 return smk_curacc(ssp, may);
1600}
1601
1602/**
1603 * smack_shm_shmat - Smack access for shmat
1604 * @shp: the object
1605 * @shmaddr: unused
1606 * @shmflg: access requested
1607 *
1608 * Returns 0 if current has the requested access, error code otherwise
1609 */
1610static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
1611 int shmflg)
1612{
1613 char *ssp = smack_of_shm(shp);
1614 int may;
1615
1616 may = smack_flags_to_may(shmflg);
1617 return smk_curacc(ssp, may);
1618}
1619
1620/**
1621 * smack_of_sem - the smack pointer for the sem
1622 * @sma: the object
1623 *
1624 * Returns a pointer to the smack value
1625 */
1626static char *smack_of_sem(struct sem_array *sma)
1627{
1628 return (char *)sma->sem_perm.security;
1629}
1630
1631/**
1632 * smack_sem_alloc_security - Set the security blob for sem
1633 * @sma: the object
1634 *
1635 * Returns 0
1636 */
1637static int smack_sem_alloc_security(struct sem_array *sma)
1638{
1639 struct kern_ipc_perm *isp = &sma->sem_perm;
1640
86a264ab 1641 isp->security = current_security();
e114e473
CS
1642 return 0;
1643}
1644
1645/**
1646 * smack_sem_free_security - Clear the security blob for sem
1647 * @sma: the object
1648 *
1649 * Clears the blob pointer
1650 */
1651static void smack_sem_free_security(struct sem_array *sma)
1652{
1653 struct kern_ipc_perm *isp = &sma->sem_perm;
1654
1655 isp->security = NULL;
1656}
1657
1658/**
1659 * smack_sem_associate - Smack access check for sem
1660 * @sma: the object
1661 * @semflg: access requested
1662 *
1663 * Returns 0 if current has the requested access, error code otherwise
1664 */
1665static int smack_sem_associate(struct sem_array *sma, int semflg)
1666{
1667 char *ssp = smack_of_sem(sma);
1668 int may;
1669
1670 may = smack_flags_to_may(semflg);
1671 return smk_curacc(ssp, may);
1672}
1673
1674/**
1675 * smack_sem_shmctl - Smack access check for sem
1676 * @sma: the object
1677 * @cmd: what it wants to do
1678 *
1679 * Returns 0 if current has the requested access, error code otherwise
1680 */
1681static int smack_sem_semctl(struct sem_array *sma, int cmd)
1682{
1d252fb8 1683 char *ssp;
e114e473
CS
1684 int may;
1685
1686 switch (cmd) {
1687 case GETPID:
1688 case GETNCNT:
1689 case GETZCNT:
1690 case GETVAL:
1691 case GETALL:
1692 case IPC_STAT:
1693 case SEM_STAT:
1694 may = MAY_READ;
1695 break;
1696 case SETVAL:
1697 case SETALL:
1698 case IPC_RMID:
1699 case IPC_SET:
1700 may = MAY_READWRITE;
1701 break;
1702 case IPC_INFO:
1703 case SEM_INFO:
1704 /*
1705 * System level information
1706 */
1707 return 0;
1708 default:
1709 return -EINVAL;
1710 }
1711
1d252fb8 1712 ssp = smack_of_sem(sma);
e114e473
CS
1713 return smk_curacc(ssp, may);
1714}
1715
1716/**
1717 * smack_sem_semop - Smack checks of semaphore operations
1718 * @sma: the object
1719 * @sops: unused
1720 * @nsops: unused
1721 * @alter: unused
1722 *
1723 * Treated as read and write in all cases.
1724 *
1725 * Returns 0 if access is allowed, error code otherwise
1726 */
1727static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
1728 unsigned nsops, int alter)
1729{
1730 char *ssp = smack_of_sem(sma);
1731
1732 return smk_curacc(ssp, MAY_READWRITE);
1733}
1734
1735/**
1736 * smack_msg_alloc_security - Set the security blob for msg
1737 * @msq: the object
1738 *
1739 * Returns 0
1740 */
1741static int smack_msg_queue_alloc_security(struct msg_queue *msq)
1742{
1743 struct kern_ipc_perm *kisp = &msq->q_perm;
1744
86a264ab 1745 kisp->security = current_security();
e114e473
CS
1746 return 0;
1747}
1748
1749/**
1750 * smack_msg_free_security - Clear the security blob for msg
1751 * @msq: the object
1752 *
1753 * Clears the blob pointer
1754 */
1755static void smack_msg_queue_free_security(struct msg_queue *msq)
1756{
1757 struct kern_ipc_perm *kisp = &msq->q_perm;
1758
1759 kisp->security = NULL;
1760}
1761
1762/**
1763 * smack_of_msq - the smack pointer for the msq
1764 * @msq: the object
1765 *
1766 * Returns a pointer to the smack value
1767 */
1768static char *smack_of_msq(struct msg_queue *msq)
1769{
1770 return (char *)msq->q_perm.security;
1771}
1772
1773/**
1774 * smack_msg_queue_associate - Smack access check for msg_queue
1775 * @msq: the object
1776 * @msqflg: access requested
1777 *
1778 * Returns 0 if current has the requested access, error code otherwise
1779 */
1780static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
1781{
1782 char *msp = smack_of_msq(msq);
1783 int may;
1784
1785 may = smack_flags_to_may(msqflg);
1786 return smk_curacc(msp, may);
1787}
1788
1789/**
1790 * smack_msg_queue_msgctl - Smack access check for msg_queue
1791 * @msq: the object
1792 * @cmd: what it wants to do
1793 *
1794 * Returns 0 if current has the requested access, error code otherwise
1795 */
1796static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
1797{
1d252fb8 1798 char *msp;
e114e473
CS
1799 int may;
1800
1801 switch (cmd) {
1802 case IPC_STAT:
1803 case MSG_STAT:
1804 may = MAY_READ;
1805 break;
1806 case IPC_SET:
1807 case IPC_RMID:
1808 may = MAY_READWRITE;
1809 break;
1810 case IPC_INFO:
1811 case MSG_INFO:
1812 /*
1813 * System level information
1814 */
1815 return 0;
1816 default:
1817 return -EINVAL;
1818 }
1819
1d252fb8 1820 msp = smack_of_msq(msq);
e114e473
CS
1821 return smk_curacc(msp, may);
1822}
1823
1824/**
1825 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1826 * @msq: the object
1827 * @msg: unused
1828 * @msqflg: access requested
1829 *
1830 * Returns 0 if current has the requested access, error code otherwise
1831 */
1832static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
1833 int msqflg)
1834{
1835 char *msp = smack_of_msq(msq);
1836 int rc;
1837
1838 rc = smack_flags_to_may(msqflg);
1839 return smk_curacc(msp, rc);
1840}
1841
1842/**
1843 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1844 * @msq: the object
1845 * @msg: unused
1846 * @target: unused
1847 * @type: unused
1848 * @mode: unused
1849 *
1850 * Returns 0 if current has read and write access, error code otherwise
1851 */
1852static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
1853 struct task_struct *target, long type, int mode)
1854{
1855 char *msp = smack_of_msq(msq);
1856
1857 return smk_curacc(msp, MAY_READWRITE);
1858}
1859
1860/**
1861 * smack_ipc_permission - Smack access for ipc_permission()
1862 * @ipp: the object permissions
1863 * @flag: access requested
1864 *
1865 * Returns 0 if current has read and write access, error code otherwise
1866 */
1867static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
1868{
1869 char *isp = ipp->security;
1870 int may;
1871
1872 may = smack_flags_to_may(flag);
1873 return smk_curacc(isp, may);
1874}
1875
d20bdda6
AD
1876/**
1877 * smack_ipc_getsecid - Extract smack security id
1878 * @ipcp: the object permissions
1879 * @secid: where result will be saved
1880 */
1881static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
1882{
1883 char *smack = ipp->security;
1884
1885 *secid = smack_to_secid(smack);
1886}
1887
e114e473
CS
1888/**
1889 * smack_d_instantiate - Make sure the blob is correct on an inode
1890 * @opt_dentry: unused
1891 * @inode: the object
1892 *
1893 * Set the inode's security blob if it hasn't been done already.
1894 */
1895static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
1896{
1897 struct super_block *sbp;
1898 struct superblock_smack *sbsp;
1899 struct inode_smack *isp;
86a264ab 1900 char *csp = current_security();
e114e473
CS
1901 char *fetched;
1902 char *final;
1903 struct dentry *dp;
1904
1905 if (inode == NULL)
1906 return;
1907
1908 isp = inode->i_security;
1909
1910 mutex_lock(&isp->smk_lock);
1911 /*
1912 * If the inode is already instantiated
1913 * take the quick way out
1914 */
1915 if (isp->smk_flags & SMK_INODE_INSTANT)
1916 goto unlockandout;
1917
1918 sbp = inode->i_sb;
1919 sbsp = sbp->s_security;
1920 /*
1921 * We're going to use the superblock default label
1922 * if there's no label on the file.
1923 */
1924 final = sbsp->smk_default;
1925
e97dcb0e
CS
1926 /*
1927 * If this is the root inode the superblock
1928 * may be in the process of initialization.
1929 * If that is the case use the root value out
1930 * of the superblock.
1931 */
1932 if (opt_dentry->d_parent == opt_dentry) {
1933 isp->smk_inode = sbsp->smk_root;
1934 isp->smk_flags |= SMK_INODE_INSTANT;
1935 goto unlockandout;
1936 }
1937
e114e473
CS
1938 /*
1939 * This is pretty hackish.
1940 * Casey says that we shouldn't have to do
1941 * file system specific code, but it does help
1942 * with keeping it simple.
1943 */
1944 switch (sbp->s_magic) {
1945 case SMACK_MAGIC:
1946 /*
1947 * Casey says that it's a little embarassing
1948 * that the smack file system doesn't do
1949 * extended attributes.
1950 */
1951 final = smack_known_star.smk_known;
1952 break;
1953 case PIPEFS_MAGIC:
1954 /*
1955 * Casey says pipes are easy (?)
1956 */
1957 final = smack_known_star.smk_known;
1958 break;
1959 case DEVPTS_SUPER_MAGIC:
1960 /*
1961 * devpts seems content with the label of the task.
1962 * Programs that change smack have to treat the
1963 * pty with respect.
1964 */
1965 final = csp;
1966 break;
1967 case SOCKFS_MAGIC:
1968 /*
1969 * Casey says sockets get the smack of the task.
1970 */
1971 final = csp;
1972 break;
1973 case PROC_SUPER_MAGIC:
1974 /*
1975 * Casey says procfs appears not to care.
1976 * The superblock default suffices.
1977 */
1978 break;
1979 case TMPFS_MAGIC:
1980 /*
1981 * Device labels should come from the filesystem,
1982 * but watch out, because they're volitile,
1983 * getting recreated on every reboot.
1984 */
1985 final = smack_known_star.smk_known;
1986 /*
1987 * No break.
1988 *
1989 * If a smack value has been set we want to use it,
1990 * but since tmpfs isn't giving us the opportunity
1991 * to set mount options simulate setting the
1992 * superblock default.
1993 */
1994 default:
1995 /*
1996 * This isn't an understood special case.
1997 * Get the value from the xattr.
1998 *
1999 * No xattr support means, alas, no SMACK label.
2000 * Use the aforeapplied default.
2001 * It would be curious if the label of the task
2002 * does not match that assigned.
2003 */
2004 if (inode->i_op->getxattr == NULL)
2005 break;
2006 /*
2007 * Get the dentry for xattr.
2008 */
2009 if (opt_dentry == NULL) {
2010 dp = d_find_alias(inode);
2011 if (dp == NULL)
2012 break;
2013 } else {
2014 dp = dget(opt_dentry);
2015 if (dp == NULL)
2016 break;
2017 }
2018
2019 fetched = smk_fetch(inode, dp);
2020 if (fetched != NULL)
2021 final = fetched;
2022
2023 dput(dp);
2024 break;
2025 }
2026
2027 if (final == NULL)
2028 isp->smk_inode = csp;
2029 else
2030 isp->smk_inode = final;
2031
2032 isp->smk_flags |= SMK_INODE_INSTANT;
2033
2034unlockandout:
2035 mutex_unlock(&isp->smk_lock);
2036 return;
2037}
2038
2039/**
2040 * smack_getprocattr - Smack process attribute access
2041 * @p: the object task
2042 * @name: the name of the attribute in /proc/.../attr
2043 * @value: where to put the result
2044 *
2045 * Places a copy of the task Smack into value
2046 *
2047 * Returns the length of the smack label or an error code
2048 */
2049static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2050{
2051 char *cp;
2052 int slen;
2053
2054 if (strcmp(name, "current") != 0)
2055 return -EINVAL;
2056
c69e8d9c 2057 cp = kstrdup(task_security(p), GFP_KERNEL);
e114e473
CS
2058 if (cp == NULL)
2059 return -ENOMEM;
2060
2061 slen = strlen(cp);
2062 *value = cp;
2063 return slen;
2064}
2065
2066/**
2067 * smack_setprocattr - Smack process attribute setting
2068 * @p: the object task
2069 * @name: the name of the attribute in /proc/.../attr
2070 * @value: the value to set
2071 * @size: the size of the value
2072 *
2073 * Sets the Smack value of the task. Only setting self
2074 * is permitted and only with privilege
2075 *
2076 * Returns the length of the smack label or an error code
2077 */
2078static int smack_setprocattr(struct task_struct *p, char *name,
2079 void *value, size_t size)
2080{
d84f4f99 2081 struct cred *new;
e114e473
CS
2082 char *newsmack;
2083
e114e473
CS
2084 /*
2085 * Changing another process' Smack value is too dangerous
2086 * and supports no sane use case.
2087 */
2088 if (p != current)
2089 return -EPERM;
2090
5cd9c58f
DH
2091 if (!capable(CAP_MAC_ADMIN))
2092 return -EPERM;
2093
e114e473
CS
2094 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2095 return -EINVAL;
2096
2097 if (strcmp(name, "current") != 0)
2098 return -EINVAL;
2099
2100 newsmack = smk_import(value, size);
2101 if (newsmack == NULL)
2102 return -EINVAL;
2103
d84f4f99
DH
2104 new = prepare_creds();
2105 if (!new)
2106 return -ENOMEM;
2107 new->security = newsmack;
2108 commit_creds(new);
e114e473
CS
2109 return size;
2110}
2111
2112/**
2113 * smack_unix_stream_connect - Smack access on UDS
2114 * @sock: one socket
2115 * @other: the other socket
2116 * @newsk: unused
2117 *
2118 * Return 0 if a subject with the smack of sock could access
2119 * an object with the smack of other, otherwise an error code
2120 */
2121static int smack_unix_stream_connect(struct socket *sock,
2122 struct socket *other, struct sock *newsk)
2123{
2124 struct inode *sp = SOCK_INODE(sock);
2125 struct inode *op = SOCK_INODE(other);
2126
2127 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE);
2128}
2129
2130/**
2131 * smack_unix_may_send - Smack access on UDS
2132 * @sock: one socket
2133 * @other: the other socket
2134 *
2135 * Return 0 if a subject with the smack of sock could access
2136 * an object with the smack of other, otherwise an error code
2137 */
2138static int smack_unix_may_send(struct socket *sock, struct socket *other)
2139{
2140 struct inode *sp = SOCK_INODE(sock);
2141 struct inode *op = SOCK_INODE(other);
2142
2143 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE);
2144}
2145
2146/**
2147 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat
2148 * pair to smack
2149 * @sap: netlabel secattr
2150 * @sip: where to put the result
2151 *
2152 * Copies a smack label into sip
2153 */
2154static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2155{
2156 char smack[SMK_LABELLEN];
2157 int pcat;
2158
2159 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) == 0) {
2160 /*
2161 * If there are flags but no level netlabel isn't
2162 * behaving the way we expect it to.
2163 *
2164 * Without guidance regarding the smack value
2165 * for the packet fall back on the network
2166 * ambient value.
2167 */
2168 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
2169 return;
2170 }
2171 /*
2172 * Get the categories, if any
2173 */
2174 memset(smack, '\0', SMK_LABELLEN);
2175 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2176 for (pcat = -1;;) {
2177 pcat = netlbl_secattr_catmap_walk(sap->attr.mls.cat,
2178 pcat + 1);
2179 if (pcat < 0)
2180 break;
2181 smack_catset_bit(pcat, smack);
2182 }
2183 /*
2184 * If it is CIPSO using smack direct mapping
2185 * we are already done. WeeHee.
2186 */
2187 if (sap->attr.mls.lvl == smack_cipso_direct) {
2188 memcpy(sip, smack, SMK_MAXLEN);
2189 return;
2190 }
2191 /*
2192 * Look it up in the supplied table if it is not a direct mapping.
2193 */
2194 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
2195 return;
2196}
2197
2198/**
2199 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2200 * @sk: socket
2201 * @skb: packet
2202 *
2203 * Returns 0 if the packet should be delivered, an error code otherwise
2204 */
2205static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2206{
2207 struct netlbl_lsm_secattr secattr;
2208 struct socket_smack *ssp = sk->sk_security;
2209 char smack[SMK_LABELLEN];
2210 int rc;
2211
2212 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2213 return 0;
2214
2215 /*
2216 * Translate what netlabel gave us.
2217 */
2218 memset(smack, '\0', SMK_LABELLEN);
2219 netlbl_secattr_init(&secattr);
2220 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
2221 if (rc == 0)
2222 smack_from_secattr(&secattr, smack);
2223 else
2224 strncpy(smack, smack_net_ambient, SMK_MAXLEN);
2225 netlbl_secattr_destroy(&secattr);
2226 /*
2227 * Receiving a packet requires that the other end
2228 * be able to write here. Read access is not required.
2229 * This is the simplist possible security model
2230 * for networking.
2231 */
a8134296
PM
2232 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2233 if (rc != 0)
2234 netlbl_skbuff_err(skb, rc, 0);
2235 return rc;
e114e473
CS
2236}
2237
2238/**
2239 * smack_socket_getpeersec_stream - pull in packet label
2240 * @sock: the socket
2241 * @optval: user's destination
2242 * @optlen: size thereof
2243 * @len: max thereoe
2244 *
2245 * returns zero on success, an error code otherwise
2246 */
2247static int smack_socket_getpeersec_stream(struct socket *sock,
2248 char __user *optval,
2249 int __user *optlen, unsigned len)
2250{
2251 struct socket_smack *ssp;
2252 int slen;
2253 int rc = 0;
2254
2255 ssp = sock->sk->sk_security;
2256 slen = strlen(ssp->smk_packet) + 1;
2257
2258 if (slen > len)
2259 rc = -ERANGE;
2260 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2261 rc = -EFAULT;
2262
2263 if (put_user(slen, optlen) != 0)
2264 rc = -EFAULT;
2265
2266 return rc;
2267}
2268
2269
2270/**
2271 * smack_socket_getpeersec_dgram - pull in packet label
2272 * @sock: the socket
2273 * @skb: packet data
2274 * @secid: pointer to where to put the secid of the packet
2275 *
2276 * Sets the netlabel socket state on sk from parent
2277 */
2278static int smack_socket_getpeersec_dgram(struct socket *sock,
2279 struct sk_buff *skb, u32 *secid)
2280
2281{
2282 struct netlbl_lsm_secattr secattr;
2283 struct sock *sk;
2284 char smack[SMK_LABELLEN];
2285 int family = PF_INET;
2286 u32 s;
2287 int rc;
2288
2289 /*
2290 * Only works for families with packets.
2291 */
2292 if (sock != NULL) {
2293 sk = sock->sk;
2294 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2295 return 0;
2296 family = sk->sk_family;
2297 }
2298 /*
2299 * Translate what netlabel gave us.
2300 */
2301 memset(smack, '\0', SMK_LABELLEN);
2302 netlbl_secattr_init(&secattr);
2303 rc = netlbl_skbuff_getattr(skb, family, &secattr);
2304 if (rc == 0)
2305 smack_from_secattr(&secattr, smack);
2306 netlbl_secattr_destroy(&secattr);
2307
2308 /*
2309 * Give up if we couldn't get anything
2310 */
2311 if (rc != 0)
2312 return rc;
2313
2314 s = smack_to_secid(smack);
2315 if (s == 0)
2316 return -EINVAL;
2317
2318 *secid = s;
2319 return 0;
2320}
2321
2322/**
2323 * smack_sock_graft - graft access state between two sockets
2324 * @sk: fresh sock
2325 * @parent: donor socket
2326 *
2327 * Sets the netlabel socket state on sk from parent
2328 */
2329static void smack_sock_graft(struct sock *sk, struct socket *parent)
2330{
2331 struct socket_smack *ssp;
2332 int rc;
2333
2334 if (sk == NULL)
2335 return;
2336
2337 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2338 return;
2339
2340 ssp = sk->sk_security;
86a264ab 2341 ssp->smk_in = ssp->smk_out = current_security();
e114e473
CS
2342 ssp->smk_packet[0] = '\0';
2343
2344 rc = smack_netlabel(sk);
4bc87e62
CS
2345 if (rc != 0)
2346 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
2347 __func__, -rc);
e114e473
CS
2348}
2349
2350/**
2351 * smack_inet_conn_request - Smack access check on connect
2352 * @sk: socket involved
2353 * @skb: packet
2354 * @req: unused
2355 *
2356 * Returns 0 if a task with the packet label could write to
2357 * the socket, otherwise an error code
2358 */
2359static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
2360 struct request_sock *req)
2361{
2362 struct netlbl_lsm_secattr skb_secattr;
2363 struct socket_smack *ssp = sk->sk_security;
2364 char smack[SMK_LABELLEN];
2365 int rc;
2366
2367 if (skb == NULL)
2368 return -EACCES;
2369
2370 memset(smack, '\0', SMK_LABELLEN);
2371 netlbl_secattr_init(&skb_secattr);
2372 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr);
2373 if (rc == 0)
2374 smack_from_secattr(&skb_secattr, smack);
2375 else
2376 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
2377 netlbl_secattr_destroy(&skb_secattr);
2378 /*
2379 * Receiving a packet requires that the other end
2380 * be able to write here. Read access is not required.
2381 *
2382 * If the request is successful save the peer's label
2383 * so that SO_PEERCRED can report it.
2384 */
2385 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2386 if (rc == 0)
2387 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
2388
2389 return rc;
2390}
2391
2392/*
2393 * Key management security hooks
2394 *
2395 * Casey has not tested key support very heavily.
2396 * The permission check is most likely too restrictive.
2397 * If you care about keys please have a look.
2398 */
2399#ifdef CONFIG_KEYS
2400
2401/**
2402 * smack_key_alloc - Set the key security blob
2403 * @key: object
d84f4f99 2404 * @cred: the credentials to use
e114e473
CS
2405 * @flags: unused
2406 *
2407 * No allocation required
2408 *
2409 * Returns 0
2410 */
d84f4f99 2411static int smack_key_alloc(struct key *key, const struct cred *cred,
e114e473
CS
2412 unsigned long flags)
2413{
d84f4f99 2414 key->security = cred->security;
e114e473
CS
2415 return 0;
2416}
2417
2418/**
2419 * smack_key_free - Clear the key security blob
2420 * @key: the object
2421 *
2422 * Clear the blob pointer
2423 */
2424static void smack_key_free(struct key *key)
2425{
2426 key->security = NULL;
2427}
2428
2429/*
2430 * smack_key_permission - Smack access on a key
2431 * @key_ref: gets to the object
d84f4f99 2432 * @cred: the credentials to use
e114e473
CS
2433 * @perm: unused
2434 *
2435 * Return 0 if the task has read and write to the object,
2436 * an error code otherwise
2437 */
2438static int smack_key_permission(key_ref_t key_ref,
d84f4f99 2439 const struct cred *cred, key_perm_t perm)
e114e473
CS
2440{
2441 struct key *keyp;
2442
2443 keyp = key_ref_to_ptr(key_ref);
2444 if (keyp == NULL)
2445 return -EINVAL;
2446 /*
2447 * If the key hasn't been initialized give it access so that
2448 * it may do so.
2449 */
2450 if (keyp->security == NULL)
2451 return 0;
2452 /*
2453 * This should not occur
2454 */
d84f4f99 2455 if (cred->security == NULL)
e114e473
CS
2456 return -EACCES;
2457
d84f4f99 2458 return smk_access(cred->security, keyp->security, MAY_READWRITE);
e114e473
CS
2459}
2460#endif /* CONFIG_KEYS */
2461
d20bdda6
AD
2462/*
2463 * Smack Audit hooks
2464 *
2465 * Audit requires a unique representation of each Smack specific
2466 * rule. This unique representation is used to distinguish the
2467 * object to be audited from remaining kernel objects and also
2468 * works as a glue between the audit hooks.
2469 *
2470 * Since repository entries are added but never deleted, we'll use
2471 * the smack_known label address related to the given audit rule as
2472 * the needed unique representation. This also better fits the smack
2473 * model where nearly everything is a label.
2474 */
2475#ifdef CONFIG_AUDIT
2476
2477/**
2478 * smack_audit_rule_init - Initialize a smack audit rule
2479 * @field: audit rule fields given from user-space (audit.h)
2480 * @op: required testing operator (=, !=, >, <, ...)
2481 * @rulestr: smack label to be audited
2482 * @vrule: pointer to save our own audit rule representation
2483 *
2484 * Prepare to audit cases where (@field @op @rulestr) is true.
2485 * The label to be audited is created if necessay.
2486 */
2487static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2488{
2489 char **rule = (char **)vrule;
2490 *rule = NULL;
2491
2492 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2493 return -EINVAL;
2494
2495 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2496 return -EINVAL;
2497
2498 *rule = smk_import(rulestr, 0);
2499
2500 return 0;
2501}
2502
2503/**
2504 * smack_audit_rule_known - Distinguish Smack audit rules
2505 * @krule: rule of interest, in Audit kernel representation format
2506 *
2507 * This is used to filter Smack rules from remaining Audit ones.
2508 * If it's proved that this rule belongs to us, the
2509 * audit_rule_match hook will be called to do the final judgement.
2510 */
2511static int smack_audit_rule_known(struct audit_krule *krule)
2512{
2513 struct audit_field *f;
2514 int i;
2515
2516 for (i = 0; i < krule->field_count; i++) {
2517 f = &krule->fields[i];
2518
2519 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
2520 return 1;
2521 }
2522
2523 return 0;
2524}
2525
2526/**
2527 * smack_audit_rule_match - Audit given object ?
2528 * @secid: security id for identifying the object to test
2529 * @field: audit rule flags given from user-space
2530 * @op: required testing operator
2531 * @vrule: smack internal rule presentation
2532 * @actx: audit context associated with the check
2533 *
2534 * The core Audit hook. It's used to take the decision of
2535 * whether to audit or not to audit a given object.
2536 */
2537static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
2538 struct audit_context *actx)
2539{
2540 char *smack;
2541 char *rule = vrule;
2542
2543 if (!rule) {
2544 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
2545 "Smack: missing rule\n");
2546 return -ENOENT;
2547 }
2548
2549 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2550 return 0;
2551
2552 smack = smack_from_secid(secid);
2553
2554 /*
2555 * No need to do string comparisons. If a match occurs,
2556 * both pointers will point to the same smack_known
2557 * label.
2558 */
2559 if (op == AUDIT_EQUAL)
2560 return (rule == smack);
2561 if (op == AUDIT_NOT_EQUAL)
2562 return (rule != smack);
2563
2564 return 0;
2565}
2566
2567/**
2568 * smack_audit_rule_free - free smack rule representation
2569 * @vrule: rule to be freed.
2570 *
2571 * No memory was allocated.
2572 */
2573static void smack_audit_rule_free(void *vrule)
2574{
2575 /* No-op */
2576}
2577
2578#endif /* CONFIG_AUDIT */
2579
e114e473
CS
2580/*
2581 * smack_secid_to_secctx - return the smack label for a secid
2582 * @secid: incoming integer
2583 * @secdata: destination
2584 * @seclen: how long it is
2585 *
2586 * Exists for networking code.
2587 */
2588static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
2589{
2590 char *sp = smack_from_secid(secid);
2591
2592 *secdata = sp;
2593 *seclen = strlen(sp);
2594 return 0;
2595}
2596
4bc87e62
CS
2597/*
2598 * smack_secctx_to_secid - return the secid for a smack label
2599 * @secdata: smack label
2600 * @seclen: how long result is
2601 * @secid: outgoing integer
2602 *
2603 * Exists for audit and networking code.
2604 */
e52c1764 2605static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4bc87e62
CS
2606{
2607 *secid = smack_to_secid(secdata);
2608 return 0;
2609}
2610
e114e473
CS
2611/*
2612 * smack_release_secctx - don't do anything.
2613 * @key_ref: unused
2614 * @context: unused
2615 * @perm: unused
2616 *
2617 * Exists to make sure nothing gets done, and properly
2618 */
2619static void smack_release_secctx(char *secdata, u32 seclen)
2620{
2621}
2622
076c54c5
AD
2623struct security_operations smack_ops = {
2624 .name = "smack",
2625
5cd9c58f
DH
2626 .ptrace_may_access = smack_ptrace_may_access,
2627 .ptrace_traceme = smack_ptrace_traceme,
e114e473 2628 .capget = cap_capget,
d84f4f99 2629 .capset = cap_capset,
e114e473
CS
2630 .capable = cap_capable,
2631 .syslog = smack_syslog,
2632 .settime = cap_settime,
2633 .vm_enough_memory = cap_vm_enough_memory,
2634
a6f76f23 2635 .bprm_set_creds = cap_bprm_set_creds,
e114e473
CS
2636 .bprm_secureexec = cap_bprm_secureexec,
2637
2638 .sb_alloc_security = smack_sb_alloc_security,
2639 .sb_free_security = smack_sb_free_security,
2640 .sb_copy_data = smack_sb_copy_data,
2641 .sb_kern_mount = smack_sb_kern_mount,
2642 .sb_statfs = smack_sb_statfs,
2643 .sb_mount = smack_sb_mount,
2644 .sb_umount = smack_sb_umount,
2645
2646 .inode_alloc_security = smack_inode_alloc_security,
2647 .inode_free_security = smack_inode_free_security,
2648 .inode_init_security = smack_inode_init_security,
2649 .inode_link = smack_inode_link,
2650 .inode_unlink = smack_inode_unlink,
2651 .inode_rmdir = smack_inode_rmdir,
2652 .inode_rename = smack_inode_rename,
2653 .inode_permission = smack_inode_permission,
2654 .inode_setattr = smack_inode_setattr,
2655 .inode_getattr = smack_inode_getattr,
2656 .inode_setxattr = smack_inode_setxattr,
2657 .inode_post_setxattr = smack_inode_post_setxattr,
2658 .inode_getxattr = smack_inode_getxattr,
2659 .inode_removexattr = smack_inode_removexattr,
bcdca225
CS
2660 .inode_need_killpriv = cap_inode_need_killpriv,
2661 .inode_killpriv = cap_inode_killpriv,
e114e473
CS
2662 .inode_getsecurity = smack_inode_getsecurity,
2663 .inode_setsecurity = smack_inode_setsecurity,
2664 .inode_listsecurity = smack_inode_listsecurity,
d20bdda6 2665 .inode_getsecid = smack_inode_getsecid,
e114e473
CS
2666
2667 .file_permission = smack_file_permission,
2668 .file_alloc_security = smack_file_alloc_security,
2669 .file_free_security = smack_file_free_security,
2670 .file_ioctl = smack_file_ioctl,
2671 .file_lock = smack_file_lock,
2672 .file_fcntl = smack_file_fcntl,
2673 .file_set_fowner = smack_file_set_fowner,
2674 .file_send_sigiotask = smack_file_send_sigiotask,
2675 .file_receive = smack_file_receive,
2676
f1752eec 2677 .cred_free = smack_cred_free,
d84f4f99
DH
2678 .cred_prepare = smack_cred_prepare,
2679 .cred_commit = smack_cred_commit,
3a3b7ce9
DH
2680 .kernel_act_as = smack_kernel_act_as,
2681 .kernel_create_files_as = smack_kernel_create_files_as,
d84f4f99 2682 .task_fix_setuid = cap_task_fix_setuid,
e114e473
CS
2683 .task_setpgid = smack_task_setpgid,
2684 .task_getpgid = smack_task_getpgid,
2685 .task_getsid = smack_task_getsid,
2686 .task_getsecid = smack_task_getsecid,
2687 .task_setnice = smack_task_setnice,
2688 .task_setioprio = smack_task_setioprio,
2689 .task_getioprio = smack_task_getioprio,
2690 .task_setscheduler = smack_task_setscheduler,
2691 .task_getscheduler = smack_task_getscheduler,
2692 .task_movememory = smack_task_movememory,
2693 .task_kill = smack_task_kill,
2694 .task_wait = smack_task_wait,
e114e473 2695 .task_to_inode = smack_task_to_inode,
1236cc3c 2696 .task_prctl = cap_task_prctl,
e114e473
CS
2697
2698 .ipc_permission = smack_ipc_permission,
d20bdda6 2699 .ipc_getsecid = smack_ipc_getsecid,
e114e473
CS
2700
2701 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
2702 .msg_msg_free_security = smack_msg_msg_free_security,
2703
2704 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
2705 .msg_queue_free_security = smack_msg_queue_free_security,
2706 .msg_queue_associate = smack_msg_queue_associate,
2707 .msg_queue_msgctl = smack_msg_queue_msgctl,
2708 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
2709 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
2710
2711 .shm_alloc_security = smack_shm_alloc_security,
2712 .shm_free_security = smack_shm_free_security,
2713 .shm_associate = smack_shm_associate,
2714 .shm_shmctl = smack_shm_shmctl,
2715 .shm_shmat = smack_shm_shmat,
2716
2717 .sem_alloc_security = smack_sem_alloc_security,
2718 .sem_free_security = smack_sem_free_security,
2719 .sem_associate = smack_sem_associate,
2720 .sem_semctl = smack_sem_semctl,
2721 .sem_semop = smack_sem_semop,
2722
2723 .netlink_send = cap_netlink_send,
2724 .netlink_recv = cap_netlink_recv,
2725
2726 .d_instantiate = smack_d_instantiate,
2727
2728 .getprocattr = smack_getprocattr,
2729 .setprocattr = smack_setprocattr,
2730
2731 .unix_stream_connect = smack_unix_stream_connect,
2732 .unix_may_send = smack_unix_may_send,
2733
2734 .socket_post_create = smack_socket_post_create,
2735 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
2736 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
2737 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
2738 .sk_alloc_security = smack_sk_alloc_security,
2739 .sk_free_security = smack_sk_free_security,
2740 .sock_graft = smack_sock_graft,
2741 .inet_conn_request = smack_inet_conn_request,
d20bdda6 2742
e114e473
CS
2743 /* key management security hooks */
2744#ifdef CONFIG_KEYS
2745 .key_alloc = smack_key_alloc,
2746 .key_free = smack_key_free,
2747 .key_permission = smack_key_permission,
2748#endif /* CONFIG_KEYS */
d20bdda6
AD
2749
2750 /* Audit hooks */
2751#ifdef CONFIG_AUDIT
2752 .audit_rule_init = smack_audit_rule_init,
2753 .audit_rule_known = smack_audit_rule_known,
2754 .audit_rule_match = smack_audit_rule_match,
2755 .audit_rule_free = smack_audit_rule_free,
2756#endif /* CONFIG_AUDIT */
2757
e114e473 2758 .secid_to_secctx = smack_secid_to_secctx,
4bc87e62 2759 .secctx_to_secid = smack_secctx_to_secid,
e114e473
CS
2760 .release_secctx = smack_release_secctx,
2761};
2762
2763/**
2764 * smack_init - initialize the smack system
2765 *
2766 * Returns 0
2767 */
2768static __init int smack_init(void)
2769{
d84f4f99
DH
2770 struct cred *cred;
2771
076c54c5
AD
2772 if (!security_module_enable(&smack_ops))
2773 return 0;
2774
e114e473
CS
2775 printk(KERN_INFO "Smack: Initializing.\n");
2776
2777 /*
2778 * Set the security state for the initial task.
2779 */
d84f4f99
DH
2780 cred = (struct cred *) current->cred;
2781 cred->security = &smack_known_floor.smk_known;
e114e473
CS
2782
2783 /*
2784 * Initialize locks
2785 */
2786 spin_lock_init(&smack_known_unset.smk_cipsolock);
2787 spin_lock_init(&smack_known_huh.smk_cipsolock);
2788 spin_lock_init(&smack_known_hat.smk_cipsolock);
2789 spin_lock_init(&smack_known_star.smk_cipsolock);
2790 spin_lock_init(&smack_known_floor.smk_cipsolock);
2791 spin_lock_init(&smack_known_invalid.smk_cipsolock);
2792
2793 /*
2794 * Register with LSM
2795 */
2796 if (register_security(&smack_ops))
2797 panic("smack: Unable to register with kernel.\n");
2798
2799 return 0;
2800}
2801
2802/*
2803 * Smack requires early initialization in order to label
2804 * all processes and objects when they are created.
2805 */
2806security_initcall(smack_init);