Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / smack / smack_lsm.c
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>
29 #include <linux/audit.h>
30
31 #include "smack.h"
32
33 /*
34 * I hope these are the hokeyist lines of code in the module. Casey.
35 */
36 #define DEVPTS_SUPER_MAGIC 0x1cd1
37 #define SOCKFS_MAGIC 0x534F434B
38 #define TMPFS_MAGIC 0x01021994
39
40 /**
41 * smk_fetch - Fetch the smack label from a file.
42 * @ip: a pointer to the inode
43 * @dp: a pointer to the dentry
44 *
45 * Returns a pointer to the master list entry for the Smack label
46 * or NULL if there was no label to fetch.
47 */
48 static char *smk_fetch(struct inode *ip, struct dentry *dp)
49 {
50 int rc;
51 char in[SMK_LABELLEN];
52
53 if (ip->i_op->getxattr == NULL)
54 return NULL;
55
56 rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN);
57 if (rc < 0)
58 return NULL;
59
60 return smk_import(in, rc);
61 }
62
63 /**
64 * new_inode_smack - allocate an inode security blob
65 * @smack: a pointer to the Smack label to use in the blob
66 *
67 * Returns the new blob or NULL if there's no memory available
68 */
69 struct inode_smack *new_inode_smack(char *smack)
70 {
71 struct inode_smack *isp;
72
73 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
74 if (isp == NULL)
75 return NULL;
76
77 isp->smk_inode = smack;
78 isp->smk_flags = 0;
79 mutex_init(&isp->smk_lock);
80
81 return isp;
82 }
83
84 /*
85 * LSM hooks.
86 * We he, that is fun!
87 */
88
89 /**
90 * smack_ptrace - Smack approval on ptrace
91 * @ptp: parent task pointer
92 * @ctp: child task pointer
93 *
94 * Returns 0 if access is OK, an error code otherwise
95 *
96 * Do the capability checks, and require read and write.
97 */
98 static int smack_ptrace(struct task_struct *ptp, struct task_struct *ctp)
99 {
100 int rc;
101
102 rc = cap_ptrace(ptp, ctp);
103 if (rc != 0)
104 return rc;
105
106 rc = smk_access(ptp->security, ctp->security, MAY_READWRITE);
107 if (rc != 0 && __capable(ptp, CAP_MAC_OVERRIDE))
108 return 0;
109
110 return rc;
111 }
112
113 /**
114 * smack_syslog - Smack approval on syslog
115 * @type: message type
116 *
117 * Require that the task has the floor label
118 *
119 * Returns 0 on success, error code otherwise.
120 */
121 static int smack_syslog(int type)
122 {
123 int rc;
124 char *sp = current->security;
125
126 rc = cap_syslog(type);
127 if (rc != 0)
128 return rc;
129
130 if (capable(CAP_MAC_OVERRIDE))
131 return 0;
132
133 if (sp != smack_known_floor.smk_known)
134 rc = -EACCES;
135
136 return rc;
137 }
138
139
140 /*
141 * Superblock Hooks.
142 */
143
144 /**
145 * smack_sb_alloc_security - allocate a superblock blob
146 * @sb: the superblock getting the blob
147 *
148 * Returns 0 on success or -ENOMEM on error.
149 */
150 static int smack_sb_alloc_security(struct super_block *sb)
151 {
152 struct superblock_smack *sbsp;
153
154 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
155
156 if (sbsp == NULL)
157 return -ENOMEM;
158
159 sbsp->smk_root = smack_known_floor.smk_known;
160 sbsp->smk_default = smack_known_floor.smk_known;
161 sbsp->smk_floor = smack_known_floor.smk_known;
162 sbsp->smk_hat = smack_known_hat.smk_known;
163 sbsp->smk_initialized = 0;
164 spin_lock_init(&sbsp->smk_sblock);
165
166 sb->s_security = sbsp;
167
168 return 0;
169 }
170
171 /**
172 * smack_sb_free_security - free a superblock blob
173 * @sb: the superblock getting the blob
174 *
175 */
176 static void smack_sb_free_security(struct super_block *sb)
177 {
178 kfree(sb->s_security);
179 sb->s_security = NULL;
180 }
181
182 /**
183 * smack_sb_copy_data - copy mount options data for processing
184 * @type: file system type
185 * @orig: where to start
186 * @smackopts
187 *
188 * Returns 0 on success or -ENOMEM on error.
189 *
190 * Copy the Smack specific mount options out of the mount
191 * options list.
192 */
193 static int smack_sb_copy_data(char *orig, char *smackopts)
194 {
195 char *cp, *commap, *otheropts, *dp;
196
197 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
198 if (otheropts == NULL)
199 return -ENOMEM;
200
201 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
202 if (strstr(cp, SMK_FSDEFAULT) == cp)
203 dp = smackopts;
204 else if (strstr(cp, SMK_FSFLOOR) == cp)
205 dp = smackopts;
206 else if (strstr(cp, SMK_FSHAT) == cp)
207 dp = smackopts;
208 else if (strstr(cp, SMK_FSROOT) == cp)
209 dp = smackopts;
210 else
211 dp = otheropts;
212
213 commap = strchr(cp, ',');
214 if (commap != NULL)
215 *commap = '\0';
216
217 if (*dp != '\0')
218 strcat(dp, ",");
219 strcat(dp, cp);
220 }
221
222 strcpy(orig, otheropts);
223 free_page((unsigned long)otheropts);
224
225 return 0;
226 }
227
228 /**
229 * smack_sb_kern_mount - Smack specific mount processing
230 * @sb: the file system superblock
231 * @data: the smack mount options
232 *
233 * Returns 0 on success, an error code on failure
234 */
235 static int smack_sb_kern_mount(struct super_block *sb, void *data)
236 {
237 struct dentry *root = sb->s_root;
238 struct inode *inode = root->d_inode;
239 struct superblock_smack *sp = sb->s_security;
240 struct inode_smack *isp;
241 char *op;
242 char *commap;
243 char *nsp;
244
245 spin_lock(&sp->smk_sblock);
246 if (sp->smk_initialized != 0) {
247 spin_unlock(&sp->smk_sblock);
248 return 0;
249 }
250 sp->smk_initialized = 1;
251 spin_unlock(&sp->smk_sblock);
252
253 for (op = data; op != NULL; op = commap) {
254 commap = strchr(op, ',');
255 if (commap != NULL)
256 *commap++ = '\0';
257
258 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
259 op += strlen(SMK_FSHAT);
260 nsp = smk_import(op, 0);
261 if (nsp != NULL)
262 sp->smk_hat = nsp;
263 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
264 op += strlen(SMK_FSFLOOR);
265 nsp = smk_import(op, 0);
266 if (nsp != NULL)
267 sp->smk_floor = nsp;
268 } else if (strncmp(op, SMK_FSDEFAULT,
269 strlen(SMK_FSDEFAULT)) == 0) {
270 op += strlen(SMK_FSDEFAULT);
271 nsp = smk_import(op, 0);
272 if (nsp != NULL)
273 sp->smk_default = nsp;
274 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
275 op += strlen(SMK_FSROOT);
276 nsp = smk_import(op, 0);
277 if (nsp != NULL)
278 sp->smk_root = nsp;
279 }
280 }
281
282 /*
283 * Initialize the root inode.
284 */
285 isp = inode->i_security;
286 if (isp == NULL)
287 inode->i_security = new_inode_smack(sp->smk_root);
288 else
289 isp->smk_inode = sp->smk_root;
290
291 return 0;
292 }
293
294 /**
295 * smack_sb_statfs - Smack check on statfs
296 * @dentry: identifies the file system in question
297 *
298 * Returns 0 if current can read the floor of the filesystem,
299 * and error code otherwise
300 */
301 static int smack_sb_statfs(struct dentry *dentry)
302 {
303 struct superblock_smack *sbp = dentry->d_sb->s_security;
304
305 return smk_curacc(sbp->smk_floor, MAY_READ);
306 }
307
308 /**
309 * smack_sb_mount - Smack check for mounting
310 * @dev_name: unused
311 * @nd: mount point
312 * @type: unused
313 * @flags: unused
314 * @data: unused
315 *
316 * Returns 0 if current can write the floor of the filesystem
317 * being mounted on, an error code otherwise.
318 */
319 static int smack_sb_mount(char *dev_name, struct path *path,
320 char *type, unsigned long flags, void *data)
321 {
322 struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
323
324 return smk_curacc(sbp->smk_floor, MAY_WRITE);
325 }
326
327 /**
328 * smack_sb_umount - Smack check for unmounting
329 * @mnt: file system to unmount
330 * @flags: unused
331 *
332 * Returns 0 if current can write the floor of the filesystem
333 * being unmounted, an error code otherwise.
334 */
335 static int smack_sb_umount(struct vfsmount *mnt, int flags)
336 {
337 struct superblock_smack *sbp;
338
339 sbp = mnt->mnt_sb->s_security;
340
341 return smk_curacc(sbp->smk_floor, MAY_WRITE);
342 }
343
344 /*
345 * Inode hooks
346 */
347
348 /**
349 * smack_inode_alloc_security - allocate an inode blob
350 * @inode - the inode in need of a blob
351 *
352 * Returns 0 if it gets a blob, -ENOMEM otherwise
353 */
354 static int smack_inode_alloc_security(struct inode *inode)
355 {
356 inode->i_security = new_inode_smack(current->security);
357 if (inode->i_security == NULL)
358 return -ENOMEM;
359 return 0;
360 }
361
362 /**
363 * smack_inode_free_security - free an inode blob
364 * @inode - the inode with a blob
365 *
366 * Clears the blob pointer in inode
367 */
368 static void smack_inode_free_security(struct inode *inode)
369 {
370 kfree(inode->i_security);
371 inode->i_security = NULL;
372 }
373
374 /**
375 * smack_inode_init_security - copy out the smack from an inode
376 * @inode: the inode
377 * @dir: unused
378 * @name: where to put the attribute name
379 * @value: where to put the attribute value
380 * @len: where to put the length of the attribute
381 *
382 * Returns 0 if it all works out, -ENOMEM if there's no memory
383 */
384 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
385 char **name, void **value, size_t *len)
386 {
387 char *isp = smk_of_inode(inode);
388
389 if (name) {
390 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
391 if (*name == NULL)
392 return -ENOMEM;
393 }
394
395 if (value) {
396 *value = kstrdup(isp, GFP_KERNEL);
397 if (*value == NULL)
398 return -ENOMEM;
399 }
400
401 if (len)
402 *len = strlen(isp) + 1;
403
404 return 0;
405 }
406
407 /**
408 * smack_inode_link - Smack check on link
409 * @old_dentry: the existing object
410 * @dir: unused
411 * @new_dentry: the new object
412 *
413 * Returns 0 if access is permitted, an error code otherwise
414 */
415 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
416 struct dentry *new_dentry)
417 {
418 int rc;
419 char *isp;
420
421 isp = smk_of_inode(old_dentry->d_inode);
422 rc = smk_curacc(isp, MAY_WRITE);
423
424 if (rc == 0 && new_dentry->d_inode != NULL) {
425 isp = smk_of_inode(new_dentry->d_inode);
426 rc = smk_curacc(isp, MAY_WRITE);
427 }
428
429 return rc;
430 }
431
432 /**
433 * smack_inode_unlink - Smack check on inode deletion
434 * @dir: containing directory object
435 * @dentry: file to unlink
436 *
437 * Returns 0 if current can write the containing directory
438 * and the object, error code otherwise
439 */
440 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
441 {
442 struct inode *ip = dentry->d_inode;
443 int rc;
444
445 /*
446 * You need write access to the thing you're unlinking
447 */
448 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE);
449 if (rc == 0)
450 /*
451 * You also need write access to the containing directory
452 */
453 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
454
455 return rc;
456 }
457
458 /**
459 * smack_inode_rmdir - Smack check on directory deletion
460 * @dir: containing directory object
461 * @dentry: directory to unlink
462 *
463 * Returns 0 if current can write the containing directory
464 * and the directory, error code otherwise
465 */
466 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
467 {
468 int rc;
469
470 /*
471 * You need write access to the thing you're removing
472 */
473 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
474 if (rc == 0)
475 /*
476 * You also need write access to the containing directory
477 */
478 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
479
480 return rc;
481 }
482
483 /**
484 * smack_inode_rename - Smack check on rename
485 * @old_inode: the old directory
486 * @old_dentry: unused
487 * @new_inode: the new directory
488 * @new_dentry: unused
489 *
490 * Read and write access is required on both the old and
491 * new directories.
492 *
493 * Returns 0 if access is permitted, an error code otherwise
494 */
495 static int smack_inode_rename(struct inode *old_inode,
496 struct dentry *old_dentry,
497 struct inode *new_inode,
498 struct dentry *new_dentry)
499 {
500 int rc;
501 char *isp;
502
503 isp = smk_of_inode(old_dentry->d_inode);
504 rc = smk_curacc(isp, MAY_READWRITE);
505
506 if (rc == 0 && new_dentry->d_inode != NULL) {
507 isp = smk_of_inode(new_dentry->d_inode);
508 rc = smk_curacc(isp, MAY_READWRITE);
509 }
510
511 return rc;
512 }
513
514 /**
515 * smack_inode_permission - Smack version of permission()
516 * @inode: the inode in question
517 * @mask: the access requested
518 * @nd: unused
519 *
520 * This is the important Smack hook.
521 *
522 * Returns 0 if access is permitted, -EACCES otherwise
523 */
524 static int smack_inode_permission(struct inode *inode, int mask,
525 struct nameidata *nd)
526 {
527 /*
528 * No permission to check. Existence test. Yup, it's there.
529 */
530 if (mask == 0)
531 return 0;
532
533 return smk_curacc(smk_of_inode(inode), mask);
534 }
535
536 /**
537 * smack_inode_setattr - Smack check for setting attributes
538 * @dentry: the object
539 * @iattr: for the force flag
540 *
541 * Returns 0 if access is permitted, an error code otherwise
542 */
543 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
544 {
545 /*
546 * Need to allow for clearing the setuid bit.
547 */
548 if (iattr->ia_valid & ATTR_FORCE)
549 return 0;
550
551 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
552 }
553
554 /**
555 * smack_inode_getattr - Smack check for getting attributes
556 * @mnt: unused
557 * @dentry: the object
558 *
559 * Returns 0 if access is permitted, an error code otherwise
560 */
561 static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
562 {
563 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
564 }
565
566 /**
567 * smack_inode_setxattr - Smack check for setting xattrs
568 * @dentry: the object
569 * @name: name of the attribute
570 * @value: unused
571 * @size: unused
572 * @flags: unused
573 *
574 * This protects the Smack attribute explicitly.
575 *
576 * Returns 0 if access is permitted, an error code otherwise
577 */
578 static int smack_inode_setxattr(struct dentry *dentry, const char *name,
579 const void *value, size_t size, int flags)
580 {
581 int rc = 0;
582
583 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
584 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
585 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
586 if (!capable(CAP_MAC_ADMIN))
587 rc = -EPERM;
588 } else
589 rc = cap_inode_setxattr(dentry, name, value, size, flags);
590
591 if (rc == 0)
592 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
593
594 return rc;
595 }
596
597 /**
598 * smack_inode_post_setxattr - Apply the Smack update approved above
599 * @dentry: object
600 * @name: attribute name
601 * @value: attribute value
602 * @size: attribute size
603 * @flags: unused
604 *
605 * Set the pointer in the inode blob to the entry found
606 * in the master label list.
607 */
608 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
609 const void *value, size_t size, int flags)
610 {
611 struct inode_smack *isp;
612 char *nsp;
613
614 /*
615 * Not SMACK
616 */
617 if (strcmp(name, XATTR_NAME_SMACK))
618 return;
619
620 if (size >= SMK_LABELLEN)
621 return;
622
623 isp = dentry->d_inode->i_security;
624
625 /*
626 * No locking is done here. This is a pointer
627 * assignment.
628 */
629 nsp = smk_import(value, size);
630 if (nsp != NULL)
631 isp->smk_inode = nsp;
632 else
633 isp->smk_inode = smack_known_invalid.smk_known;
634
635 return;
636 }
637
638 /*
639 * smack_inode_getxattr - Smack check on getxattr
640 * @dentry: the object
641 * @name: unused
642 *
643 * Returns 0 if access is permitted, an error code otherwise
644 */
645 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
646 {
647 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
648 }
649
650 /*
651 * smack_inode_removexattr - Smack check on removexattr
652 * @dentry: the object
653 * @name: name of the attribute
654 *
655 * Removing the Smack attribute requires CAP_MAC_ADMIN
656 *
657 * Returns 0 if access is permitted, an error code otherwise
658 */
659 static int smack_inode_removexattr(struct dentry *dentry, const char *name)
660 {
661 int rc = 0;
662
663 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
664 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
665 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
666 if (!capable(CAP_MAC_ADMIN))
667 rc = -EPERM;
668 } else
669 rc = cap_inode_removexattr(dentry, name);
670
671 if (rc == 0)
672 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
673
674 return rc;
675 }
676
677 /**
678 * smack_inode_getsecurity - get smack xattrs
679 * @inode: the object
680 * @name: attribute name
681 * @buffer: where to put the result
682 * @size: size of the buffer
683 * @err: unused
684 *
685 * Returns the size of the attribute or an error code
686 */
687 static int smack_inode_getsecurity(const struct inode *inode,
688 const char *name, void **buffer,
689 bool alloc)
690 {
691 struct socket_smack *ssp;
692 struct socket *sock;
693 struct super_block *sbp;
694 struct inode *ip = (struct inode *)inode;
695 char *isp;
696 int ilen;
697 int rc = 0;
698
699 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
700 isp = smk_of_inode(inode);
701 ilen = strlen(isp) + 1;
702 *buffer = isp;
703 return ilen;
704 }
705
706 /*
707 * The rest of the Smack xattrs are only on sockets.
708 */
709 sbp = ip->i_sb;
710 if (sbp->s_magic != SOCKFS_MAGIC)
711 return -EOPNOTSUPP;
712
713 sock = SOCKET_I(ip);
714 if (sock == NULL || sock->sk == NULL)
715 return -EOPNOTSUPP;
716
717 ssp = sock->sk->sk_security;
718
719 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
720 isp = ssp->smk_in;
721 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
722 isp = ssp->smk_out;
723 else
724 return -EOPNOTSUPP;
725
726 ilen = strlen(isp) + 1;
727 if (rc == 0) {
728 *buffer = isp;
729 rc = ilen;
730 }
731
732 return rc;
733 }
734
735
736 /**
737 * smack_inode_listsecurity - list the Smack attributes
738 * @inode: the object
739 * @buffer: where they go
740 * @buffer_size: size of buffer
741 *
742 * Returns 0 on success, -EINVAL otherwise
743 */
744 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
745 size_t buffer_size)
746 {
747 int len = strlen(XATTR_NAME_SMACK);
748
749 if (buffer != NULL && len <= buffer_size) {
750 memcpy(buffer, XATTR_NAME_SMACK, len);
751 return len;
752 }
753 return -EINVAL;
754 }
755
756 /**
757 * smack_inode_getsecid - Extract inode's security id
758 * @inode: inode to extract the info from
759 * @secid: where result will be saved
760 */
761 static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
762 {
763 struct inode_smack *isp = inode->i_security;
764
765 *secid = smack_to_secid(isp->smk_inode);
766 }
767
768 /*
769 * File Hooks
770 */
771
772 /**
773 * smack_file_permission - Smack check on file operations
774 * @file: unused
775 * @mask: unused
776 *
777 * Returns 0
778 *
779 * Should access checks be done on each read or write?
780 * UNICOS and SELinux say yes.
781 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
782 *
783 * I'll say no for now. Smack does not do the frequent
784 * label changing that SELinux does.
785 */
786 static int smack_file_permission(struct file *file, int mask)
787 {
788 return 0;
789 }
790
791 /**
792 * smack_file_alloc_security - assign a file security blob
793 * @file: the object
794 *
795 * The security blob for a file is a pointer to the master
796 * label list, so no allocation is done.
797 *
798 * Returns 0
799 */
800 static int smack_file_alloc_security(struct file *file)
801 {
802 file->f_security = current->security;
803 return 0;
804 }
805
806 /**
807 * smack_file_free_security - clear a file security blob
808 * @file: the object
809 *
810 * The security blob for a file is a pointer to the master
811 * label list, so no memory is freed.
812 */
813 static void smack_file_free_security(struct file *file)
814 {
815 file->f_security = NULL;
816 }
817
818 /**
819 * smack_file_ioctl - Smack check on ioctls
820 * @file: the object
821 * @cmd: what to do
822 * @arg: unused
823 *
824 * Relies heavily on the correct use of the ioctl command conventions.
825 *
826 * Returns 0 if allowed, error code otherwise
827 */
828 static int smack_file_ioctl(struct file *file, unsigned int cmd,
829 unsigned long arg)
830 {
831 int rc = 0;
832
833 if (_IOC_DIR(cmd) & _IOC_WRITE)
834 rc = smk_curacc(file->f_security, MAY_WRITE);
835
836 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
837 rc = smk_curacc(file->f_security, MAY_READ);
838
839 return rc;
840 }
841
842 /**
843 * smack_file_lock - Smack check on file locking
844 * @file: the object
845 * @cmd unused
846 *
847 * Returns 0 if current has write access, error code otherwise
848 */
849 static int smack_file_lock(struct file *file, unsigned int cmd)
850 {
851 return smk_curacc(file->f_security, MAY_WRITE);
852 }
853
854 /**
855 * smack_file_fcntl - Smack check on fcntl
856 * @file: the object
857 * @cmd: what action to check
858 * @arg: unused
859 *
860 * Returns 0 if current has access, error code otherwise
861 */
862 static int smack_file_fcntl(struct file *file, unsigned int cmd,
863 unsigned long arg)
864 {
865 int rc;
866
867 switch (cmd) {
868 case F_DUPFD:
869 case F_GETFD:
870 case F_GETFL:
871 case F_GETLK:
872 case F_GETOWN:
873 case F_GETSIG:
874 rc = smk_curacc(file->f_security, MAY_READ);
875 break;
876 case F_SETFD:
877 case F_SETFL:
878 case F_SETLK:
879 case F_SETLKW:
880 case F_SETOWN:
881 case F_SETSIG:
882 rc = smk_curacc(file->f_security, MAY_WRITE);
883 break;
884 default:
885 rc = smk_curacc(file->f_security, MAY_READWRITE);
886 }
887
888 return rc;
889 }
890
891 /**
892 * smack_file_set_fowner - set the file security blob value
893 * @file: object in question
894 *
895 * Returns 0
896 * Further research may be required on this one.
897 */
898 static int smack_file_set_fowner(struct file *file)
899 {
900 file->f_security = current->security;
901 return 0;
902 }
903
904 /**
905 * smack_file_send_sigiotask - Smack on sigio
906 * @tsk: The target task
907 * @fown: the object the signal come from
908 * @signum: unused
909 *
910 * Allow a privileged task to get signals even if it shouldn't
911 *
912 * Returns 0 if a subject with the object's smack could
913 * write to the task, an error code otherwise.
914 */
915 static int smack_file_send_sigiotask(struct task_struct *tsk,
916 struct fown_struct *fown, int signum)
917 {
918 struct file *file;
919 int rc;
920
921 /*
922 * struct fown_struct is never outside the context of a struct file
923 */
924 file = container_of(fown, struct file, f_owner);
925 rc = smk_access(file->f_security, tsk->security, MAY_WRITE);
926 if (rc != 0 && __capable(tsk, CAP_MAC_OVERRIDE))
927 return 0;
928 return rc;
929 }
930
931 /**
932 * smack_file_receive - Smack file receive check
933 * @file: the object
934 *
935 * Returns 0 if current has access, error code otherwise
936 */
937 static int smack_file_receive(struct file *file)
938 {
939 int may = 0;
940
941 /*
942 * This code relies on bitmasks.
943 */
944 if (file->f_mode & FMODE_READ)
945 may = MAY_READ;
946 if (file->f_mode & FMODE_WRITE)
947 may |= MAY_WRITE;
948
949 return smk_curacc(file->f_security, may);
950 }
951
952 /*
953 * Task hooks
954 */
955
956 /**
957 * smack_task_alloc_security - "allocate" a task blob
958 * @tsk: the task in need of a blob
959 *
960 * Smack isn't using copies of blobs. Everyone
961 * points to an immutable list. No alloc required.
962 * No data copy required.
963 *
964 * Always returns 0
965 */
966 static int smack_task_alloc_security(struct task_struct *tsk)
967 {
968 tsk->security = current->security;
969
970 return 0;
971 }
972
973 /**
974 * smack_task_free_security - "free" a task blob
975 * @task: the task with the blob
976 *
977 * Smack isn't using copies of blobs. Everyone
978 * points to an immutable list. The blobs never go away.
979 * There is no leak here.
980 */
981 static void smack_task_free_security(struct task_struct *task)
982 {
983 task->security = NULL;
984 }
985
986 /**
987 * smack_task_setpgid - Smack check on setting pgid
988 * @p: the task object
989 * @pgid: unused
990 *
991 * Return 0 if write access is permitted
992 */
993 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
994 {
995 return smk_curacc(p->security, MAY_WRITE);
996 }
997
998 /**
999 * smack_task_getpgid - Smack access check for getpgid
1000 * @p: the object task
1001 *
1002 * Returns 0 if current can read the object task, error code otherwise
1003 */
1004 static int smack_task_getpgid(struct task_struct *p)
1005 {
1006 return smk_curacc(p->security, MAY_READ);
1007 }
1008
1009 /**
1010 * smack_task_getsid - Smack access check for getsid
1011 * @p: the object task
1012 *
1013 * Returns 0 if current can read the object task, error code otherwise
1014 */
1015 static int smack_task_getsid(struct task_struct *p)
1016 {
1017 return smk_curacc(p->security, MAY_READ);
1018 }
1019
1020 /**
1021 * smack_task_getsecid - get the secid of the task
1022 * @p: the object task
1023 * @secid: where to put the result
1024 *
1025 * Sets the secid to contain a u32 version of the smack label.
1026 */
1027 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1028 {
1029 *secid = smack_to_secid(p->security);
1030 }
1031
1032 /**
1033 * smack_task_setnice - Smack check on setting nice
1034 * @p: the task object
1035 * @nice: unused
1036 *
1037 * Return 0 if write access is permitted
1038 */
1039 static int smack_task_setnice(struct task_struct *p, int nice)
1040 {
1041 int rc;
1042
1043 rc = cap_task_setnice(p, nice);
1044 if (rc == 0)
1045 rc = smk_curacc(p->security, MAY_WRITE);
1046 return rc;
1047 }
1048
1049 /**
1050 * smack_task_setioprio - Smack check on setting ioprio
1051 * @p: the task object
1052 * @ioprio: unused
1053 *
1054 * Return 0 if write access is permitted
1055 */
1056 static int smack_task_setioprio(struct task_struct *p, int ioprio)
1057 {
1058 int rc;
1059
1060 rc = cap_task_setioprio(p, ioprio);
1061 if (rc == 0)
1062 rc = smk_curacc(p->security, MAY_WRITE);
1063 return rc;
1064 }
1065
1066 /**
1067 * smack_task_getioprio - Smack check on reading ioprio
1068 * @p: the task object
1069 *
1070 * Return 0 if read access is permitted
1071 */
1072 static int smack_task_getioprio(struct task_struct *p)
1073 {
1074 return smk_curacc(p->security, MAY_READ);
1075 }
1076
1077 /**
1078 * smack_task_setscheduler - Smack check on setting scheduler
1079 * @p: the task object
1080 * @policy: unused
1081 * @lp: unused
1082 *
1083 * Return 0 if read access is permitted
1084 */
1085 static int smack_task_setscheduler(struct task_struct *p, int policy,
1086 struct sched_param *lp)
1087 {
1088 int rc;
1089
1090 rc = cap_task_setscheduler(p, policy, lp);
1091 if (rc == 0)
1092 rc = smk_curacc(p->security, MAY_WRITE);
1093 return rc;
1094 }
1095
1096 /**
1097 * smack_task_getscheduler - Smack check on reading scheduler
1098 * @p: the task object
1099 *
1100 * Return 0 if read access is permitted
1101 */
1102 static int smack_task_getscheduler(struct task_struct *p)
1103 {
1104 return smk_curacc(p->security, MAY_READ);
1105 }
1106
1107 /**
1108 * smack_task_movememory - Smack check on moving memory
1109 * @p: the task object
1110 *
1111 * Return 0 if write access is permitted
1112 */
1113 static int smack_task_movememory(struct task_struct *p)
1114 {
1115 return smk_curacc(p->security, MAY_WRITE);
1116 }
1117
1118 /**
1119 * smack_task_kill - Smack check on signal delivery
1120 * @p: the task object
1121 * @info: unused
1122 * @sig: unused
1123 * @secid: identifies the smack to use in lieu of current's
1124 *
1125 * Return 0 if write access is permitted
1126 *
1127 * The secid behavior is an artifact of an SELinux hack
1128 * in the USB code. Someday it may go away.
1129 */
1130 static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1131 int sig, u32 secid)
1132 {
1133 /*
1134 * Sending a signal requires that the sender
1135 * can write the receiver.
1136 */
1137 if (secid == 0)
1138 return smk_curacc(p->security, MAY_WRITE);
1139 /*
1140 * If the secid isn't 0 we're dealing with some USB IO
1141 * specific behavior. This is not clean. For one thing
1142 * we can't take privilege into account.
1143 */
1144 return smk_access(smack_from_secid(secid), p->security, MAY_WRITE);
1145 }
1146
1147 /**
1148 * smack_task_wait - Smack access check for waiting
1149 * @p: task to wait for
1150 *
1151 * Returns 0 if current can wait for p, error code otherwise
1152 */
1153 static int smack_task_wait(struct task_struct *p)
1154 {
1155 int rc;
1156
1157 rc = smk_access(current->security, p->security, MAY_WRITE);
1158 if (rc == 0)
1159 return 0;
1160
1161 /*
1162 * Allow the operation to succeed if either task
1163 * has privilege to perform operations that might
1164 * account for the smack labels having gotten to
1165 * be different in the first place.
1166 *
1167 * This breaks the strict subjet/object access
1168 * control ideal, taking the object's privilege
1169 * state into account in the decision as well as
1170 * the smack value.
1171 */
1172 if (capable(CAP_MAC_OVERRIDE) || __capable(p, CAP_MAC_OVERRIDE))
1173 return 0;
1174
1175 return rc;
1176 }
1177
1178 /**
1179 * smack_task_to_inode - copy task smack into the inode blob
1180 * @p: task to copy from
1181 * inode: inode to copy to
1182 *
1183 * Sets the smack pointer in the inode security blob
1184 */
1185 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1186 {
1187 struct inode_smack *isp = inode->i_security;
1188 isp->smk_inode = p->security;
1189 }
1190
1191 /*
1192 * Socket hooks.
1193 */
1194
1195 /**
1196 * smack_sk_alloc_security - Allocate a socket blob
1197 * @sk: the socket
1198 * @family: unused
1199 * @priority: memory allocation priority
1200 *
1201 * Assign Smack pointers to current
1202 *
1203 * Returns 0 on success, -ENOMEM is there's no memory
1204 */
1205 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1206 {
1207 char *csp = current->security;
1208 struct socket_smack *ssp;
1209
1210 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1211 if (ssp == NULL)
1212 return -ENOMEM;
1213
1214 ssp->smk_in = csp;
1215 ssp->smk_out = csp;
1216 ssp->smk_packet[0] = '\0';
1217
1218 sk->sk_security = ssp;
1219
1220 return 0;
1221 }
1222
1223 /**
1224 * smack_sk_free_security - Free a socket blob
1225 * @sk: the socket
1226 *
1227 * Clears the blob pointer
1228 */
1229 static void smack_sk_free_security(struct sock *sk)
1230 {
1231 kfree(sk->sk_security);
1232 }
1233
1234 /**
1235 * smack_set_catset - convert a capset to netlabel mls categories
1236 * @catset: the Smack categories
1237 * @sap: where to put the netlabel categories
1238 *
1239 * Allocates and fills attr.mls.cat
1240 */
1241 static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1242 {
1243 unsigned char *cp;
1244 unsigned char m;
1245 int cat;
1246 int rc;
1247 int byte;
1248
1249 if (!catset)
1250 return;
1251
1252 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1253 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1254 sap->attr.mls.cat->startbit = 0;
1255
1256 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1257 for (m = 0x80; m != 0; m >>= 1, cat++) {
1258 if ((m & *cp) == 0)
1259 continue;
1260 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1261 cat, GFP_ATOMIC);
1262 }
1263 }
1264
1265 /**
1266 * smack_to_secattr - fill a secattr from a smack value
1267 * @smack: the smack value
1268 * @nlsp: where the result goes
1269 *
1270 * Casey says that CIPSO is good enough for now.
1271 * It can be used to effect.
1272 * It can also be abused to effect when necessary.
1273 * Appologies to the TSIG group in general and GW in particular.
1274 */
1275 static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1276 {
1277 struct smack_cipso cipso;
1278 int rc;
1279
1280 switch (smack_net_nltype) {
1281 case NETLBL_NLTYPE_CIPSOV4:
1282 nlsp->domain = smack;
1283 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1284
1285 rc = smack_to_cipso(smack, &cipso);
1286 if (rc == 0) {
1287 nlsp->attr.mls.lvl = cipso.smk_level;
1288 smack_set_catset(cipso.smk_catset, nlsp);
1289 } else {
1290 nlsp->attr.mls.lvl = smack_cipso_direct;
1291 smack_set_catset(smack, nlsp);
1292 }
1293 break;
1294 default:
1295 break;
1296 }
1297 }
1298
1299 /**
1300 * smack_netlabel - Set the secattr on a socket
1301 * @sk: the socket
1302 *
1303 * Convert the outbound smack value (smk_out) to a
1304 * secattr and attach it to the socket.
1305 *
1306 * Returns 0 on success or an error code
1307 */
1308 static int smack_netlabel(struct sock *sk)
1309 {
1310 struct socket_smack *ssp;
1311 struct netlbl_lsm_secattr secattr;
1312 int rc;
1313
1314 ssp = sk->sk_security;
1315 netlbl_secattr_init(&secattr);
1316 smack_to_secattr(ssp->smk_out, &secattr);
1317 rc = netlbl_sock_setattr(sk, &secattr);
1318 netlbl_secattr_destroy(&secattr);
1319
1320 return rc;
1321 }
1322
1323 /**
1324 * smack_inode_setsecurity - set smack xattrs
1325 * @inode: the object
1326 * @name: attribute name
1327 * @value: attribute value
1328 * @size: size of the attribute
1329 * @flags: unused
1330 *
1331 * Sets the named attribute in the appropriate blob
1332 *
1333 * Returns 0 on success, or an error code
1334 */
1335 static int smack_inode_setsecurity(struct inode *inode, const char *name,
1336 const void *value, size_t size, int flags)
1337 {
1338 char *sp;
1339 struct inode_smack *nsp = inode->i_security;
1340 struct socket_smack *ssp;
1341 struct socket *sock;
1342 int rc = 0;
1343
1344 if (value == NULL || size > SMK_LABELLEN)
1345 return -EACCES;
1346
1347 sp = smk_import(value, size);
1348 if (sp == NULL)
1349 return -EINVAL;
1350
1351 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1352 nsp->smk_inode = sp;
1353 return 0;
1354 }
1355 /*
1356 * The rest of the Smack xattrs are only on sockets.
1357 */
1358 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1359 return -EOPNOTSUPP;
1360
1361 sock = SOCKET_I(inode);
1362 if (sock == NULL || sock->sk == NULL)
1363 return -EOPNOTSUPP;
1364
1365 ssp = sock->sk->sk_security;
1366
1367 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1368 ssp->smk_in = sp;
1369 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1370 ssp->smk_out = sp;
1371 rc = smack_netlabel(sock->sk);
1372 if (rc != 0)
1373 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
1374 __func__, -rc);
1375 } else
1376 return -EOPNOTSUPP;
1377
1378 return 0;
1379 }
1380
1381 /**
1382 * smack_socket_post_create - finish socket setup
1383 * @sock: the socket
1384 * @family: protocol family
1385 * @type: unused
1386 * @protocol: unused
1387 * @kern: unused
1388 *
1389 * Sets the netlabel information on the socket
1390 *
1391 * Returns 0 on success, and error code otherwise
1392 */
1393 static int smack_socket_post_create(struct socket *sock, int family,
1394 int type, int protocol, int kern)
1395 {
1396 if (family != PF_INET || sock->sk == NULL)
1397 return 0;
1398 /*
1399 * Set the outbound netlbl.
1400 */
1401 return smack_netlabel(sock->sk);
1402 }
1403
1404 /**
1405 * smack_flags_to_may - convert S_ to MAY_ values
1406 * @flags: the S_ value
1407 *
1408 * Returns the equivalent MAY_ value
1409 */
1410 static int smack_flags_to_may(int flags)
1411 {
1412 int may = 0;
1413
1414 if (flags & S_IRUGO)
1415 may |= MAY_READ;
1416 if (flags & S_IWUGO)
1417 may |= MAY_WRITE;
1418 if (flags & S_IXUGO)
1419 may |= MAY_EXEC;
1420
1421 return may;
1422 }
1423
1424 /**
1425 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
1426 * @msg: the object
1427 *
1428 * Returns 0
1429 */
1430 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
1431 {
1432 msg->security = current->security;
1433 return 0;
1434 }
1435
1436 /**
1437 * smack_msg_msg_free_security - Clear the security blob for msg_msg
1438 * @msg: the object
1439 *
1440 * Clears the blob pointer
1441 */
1442 static void smack_msg_msg_free_security(struct msg_msg *msg)
1443 {
1444 msg->security = NULL;
1445 }
1446
1447 /**
1448 * smack_of_shm - the smack pointer for the shm
1449 * @shp: the object
1450 *
1451 * Returns a pointer to the smack value
1452 */
1453 static char *smack_of_shm(struct shmid_kernel *shp)
1454 {
1455 return (char *)shp->shm_perm.security;
1456 }
1457
1458 /**
1459 * smack_shm_alloc_security - Set the security blob for shm
1460 * @shp: the object
1461 *
1462 * Returns 0
1463 */
1464 static int smack_shm_alloc_security(struct shmid_kernel *shp)
1465 {
1466 struct kern_ipc_perm *isp = &shp->shm_perm;
1467
1468 isp->security = current->security;
1469 return 0;
1470 }
1471
1472 /**
1473 * smack_shm_free_security - Clear the security blob for shm
1474 * @shp: the object
1475 *
1476 * Clears the blob pointer
1477 */
1478 static void smack_shm_free_security(struct shmid_kernel *shp)
1479 {
1480 struct kern_ipc_perm *isp = &shp->shm_perm;
1481
1482 isp->security = NULL;
1483 }
1484
1485 /**
1486 * smack_shm_associate - Smack access check for shm
1487 * @shp: the object
1488 * @shmflg: access requested
1489 *
1490 * Returns 0 if current has the requested access, error code otherwise
1491 */
1492 static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
1493 {
1494 char *ssp = smack_of_shm(shp);
1495 int may;
1496
1497 may = smack_flags_to_may(shmflg);
1498 return smk_curacc(ssp, may);
1499 }
1500
1501 /**
1502 * smack_shm_shmctl - Smack access check for shm
1503 * @shp: the object
1504 * @cmd: what it wants to do
1505 *
1506 * Returns 0 if current has the requested access, error code otherwise
1507 */
1508 static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
1509 {
1510 char *ssp;
1511 int may;
1512
1513 switch (cmd) {
1514 case IPC_STAT:
1515 case SHM_STAT:
1516 may = MAY_READ;
1517 break;
1518 case IPC_SET:
1519 case SHM_LOCK:
1520 case SHM_UNLOCK:
1521 case IPC_RMID:
1522 may = MAY_READWRITE;
1523 break;
1524 case IPC_INFO:
1525 case SHM_INFO:
1526 /*
1527 * System level information.
1528 */
1529 return 0;
1530 default:
1531 return -EINVAL;
1532 }
1533
1534 ssp = smack_of_shm(shp);
1535 return smk_curacc(ssp, may);
1536 }
1537
1538 /**
1539 * smack_shm_shmat - Smack access for shmat
1540 * @shp: the object
1541 * @shmaddr: unused
1542 * @shmflg: access requested
1543 *
1544 * Returns 0 if current has the requested access, error code otherwise
1545 */
1546 static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
1547 int shmflg)
1548 {
1549 char *ssp = smack_of_shm(shp);
1550 int may;
1551
1552 may = smack_flags_to_may(shmflg);
1553 return smk_curacc(ssp, may);
1554 }
1555
1556 /**
1557 * smack_of_sem - the smack pointer for the sem
1558 * @sma: the object
1559 *
1560 * Returns a pointer to the smack value
1561 */
1562 static char *smack_of_sem(struct sem_array *sma)
1563 {
1564 return (char *)sma->sem_perm.security;
1565 }
1566
1567 /**
1568 * smack_sem_alloc_security - Set the security blob for sem
1569 * @sma: the object
1570 *
1571 * Returns 0
1572 */
1573 static int smack_sem_alloc_security(struct sem_array *sma)
1574 {
1575 struct kern_ipc_perm *isp = &sma->sem_perm;
1576
1577 isp->security = current->security;
1578 return 0;
1579 }
1580
1581 /**
1582 * smack_sem_free_security - Clear the security blob for sem
1583 * @sma: the object
1584 *
1585 * Clears the blob pointer
1586 */
1587 static void smack_sem_free_security(struct sem_array *sma)
1588 {
1589 struct kern_ipc_perm *isp = &sma->sem_perm;
1590
1591 isp->security = NULL;
1592 }
1593
1594 /**
1595 * smack_sem_associate - Smack access check for sem
1596 * @sma: the object
1597 * @semflg: access requested
1598 *
1599 * Returns 0 if current has the requested access, error code otherwise
1600 */
1601 static int smack_sem_associate(struct sem_array *sma, int semflg)
1602 {
1603 char *ssp = smack_of_sem(sma);
1604 int may;
1605
1606 may = smack_flags_to_may(semflg);
1607 return smk_curacc(ssp, may);
1608 }
1609
1610 /**
1611 * smack_sem_shmctl - Smack access check for sem
1612 * @sma: the object
1613 * @cmd: what it wants to do
1614 *
1615 * Returns 0 if current has the requested access, error code otherwise
1616 */
1617 static int smack_sem_semctl(struct sem_array *sma, int cmd)
1618 {
1619 char *ssp;
1620 int may;
1621
1622 switch (cmd) {
1623 case GETPID:
1624 case GETNCNT:
1625 case GETZCNT:
1626 case GETVAL:
1627 case GETALL:
1628 case IPC_STAT:
1629 case SEM_STAT:
1630 may = MAY_READ;
1631 break;
1632 case SETVAL:
1633 case SETALL:
1634 case IPC_RMID:
1635 case IPC_SET:
1636 may = MAY_READWRITE;
1637 break;
1638 case IPC_INFO:
1639 case SEM_INFO:
1640 /*
1641 * System level information
1642 */
1643 return 0;
1644 default:
1645 return -EINVAL;
1646 }
1647
1648 ssp = smack_of_sem(sma);
1649 return smk_curacc(ssp, may);
1650 }
1651
1652 /**
1653 * smack_sem_semop - Smack checks of semaphore operations
1654 * @sma: the object
1655 * @sops: unused
1656 * @nsops: unused
1657 * @alter: unused
1658 *
1659 * Treated as read and write in all cases.
1660 *
1661 * Returns 0 if access is allowed, error code otherwise
1662 */
1663 static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
1664 unsigned nsops, int alter)
1665 {
1666 char *ssp = smack_of_sem(sma);
1667
1668 return smk_curacc(ssp, MAY_READWRITE);
1669 }
1670
1671 /**
1672 * smack_msg_alloc_security - Set the security blob for msg
1673 * @msq: the object
1674 *
1675 * Returns 0
1676 */
1677 static int smack_msg_queue_alloc_security(struct msg_queue *msq)
1678 {
1679 struct kern_ipc_perm *kisp = &msq->q_perm;
1680
1681 kisp->security = current->security;
1682 return 0;
1683 }
1684
1685 /**
1686 * smack_msg_free_security - Clear the security blob for msg
1687 * @msq: the object
1688 *
1689 * Clears the blob pointer
1690 */
1691 static void smack_msg_queue_free_security(struct msg_queue *msq)
1692 {
1693 struct kern_ipc_perm *kisp = &msq->q_perm;
1694
1695 kisp->security = NULL;
1696 }
1697
1698 /**
1699 * smack_of_msq - the smack pointer for the msq
1700 * @msq: the object
1701 *
1702 * Returns a pointer to the smack value
1703 */
1704 static char *smack_of_msq(struct msg_queue *msq)
1705 {
1706 return (char *)msq->q_perm.security;
1707 }
1708
1709 /**
1710 * smack_msg_queue_associate - Smack access check for msg_queue
1711 * @msq: the object
1712 * @msqflg: access requested
1713 *
1714 * Returns 0 if current has the requested access, error code otherwise
1715 */
1716 static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
1717 {
1718 char *msp = smack_of_msq(msq);
1719 int may;
1720
1721 may = smack_flags_to_may(msqflg);
1722 return smk_curacc(msp, may);
1723 }
1724
1725 /**
1726 * smack_msg_queue_msgctl - Smack access check for msg_queue
1727 * @msq: the object
1728 * @cmd: what it wants to do
1729 *
1730 * Returns 0 if current has the requested access, error code otherwise
1731 */
1732 static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
1733 {
1734 char *msp;
1735 int may;
1736
1737 switch (cmd) {
1738 case IPC_STAT:
1739 case MSG_STAT:
1740 may = MAY_READ;
1741 break;
1742 case IPC_SET:
1743 case IPC_RMID:
1744 may = MAY_READWRITE;
1745 break;
1746 case IPC_INFO:
1747 case MSG_INFO:
1748 /*
1749 * System level information
1750 */
1751 return 0;
1752 default:
1753 return -EINVAL;
1754 }
1755
1756 msp = smack_of_msq(msq);
1757 return smk_curacc(msp, may);
1758 }
1759
1760 /**
1761 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1762 * @msq: the object
1763 * @msg: unused
1764 * @msqflg: access requested
1765 *
1766 * Returns 0 if current has the requested access, error code otherwise
1767 */
1768 static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
1769 int msqflg)
1770 {
1771 char *msp = smack_of_msq(msq);
1772 int rc;
1773
1774 rc = smack_flags_to_may(msqflg);
1775 return smk_curacc(msp, rc);
1776 }
1777
1778 /**
1779 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1780 * @msq: the object
1781 * @msg: unused
1782 * @target: unused
1783 * @type: unused
1784 * @mode: unused
1785 *
1786 * Returns 0 if current has read and write access, error code otherwise
1787 */
1788 static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
1789 struct task_struct *target, long type, int mode)
1790 {
1791 char *msp = smack_of_msq(msq);
1792
1793 return smk_curacc(msp, MAY_READWRITE);
1794 }
1795
1796 /**
1797 * smack_ipc_permission - Smack access for ipc_permission()
1798 * @ipp: the object permissions
1799 * @flag: access requested
1800 *
1801 * Returns 0 if current has read and write access, error code otherwise
1802 */
1803 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
1804 {
1805 char *isp = ipp->security;
1806 int may;
1807
1808 may = smack_flags_to_may(flag);
1809 return smk_curacc(isp, may);
1810 }
1811
1812 /**
1813 * smack_ipc_getsecid - Extract smack security id
1814 * @ipcp: the object permissions
1815 * @secid: where result will be saved
1816 */
1817 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
1818 {
1819 char *smack = ipp->security;
1820
1821 *secid = smack_to_secid(smack);
1822 }
1823
1824 /* module stacking operations */
1825
1826 /**
1827 * smack_register_security - stack capability module
1828 * @name: module name
1829 * @ops: module operations - ignored
1830 *
1831 * Allow the capability module to register.
1832 */
1833 static int smack_register_security(const char *name,
1834 struct security_operations *ops)
1835 {
1836 if (strcmp(name, "capability") != 0)
1837 return -EINVAL;
1838
1839 printk(KERN_INFO "%s: Registering secondary module %s\n",
1840 __func__, name);
1841
1842 return 0;
1843 }
1844
1845 /**
1846 * smack_d_instantiate - Make sure the blob is correct on an inode
1847 * @opt_dentry: unused
1848 * @inode: the object
1849 *
1850 * Set the inode's security blob if it hasn't been done already.
1851 */
1852 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
1853 {
1854 struct super_block *sbp;
1855 struct superblock_smack *sbsp;
1856 struct inode_smack *isp;
1857 char *csp = current->security;
1858 char *fetched;
1859 char *final;
1860 struct dentry *dp;
1861
1862 if (inode == NULL)
1863 return;
1864
1865 isp = inode->i_security;
1866
1867 mutex_lock(&isp->smk_lock);
1868 /*
1869 * If the inode is already instantiated
1870 * take the quick way out
1871 */
1872 if (isp->smk_flags & SMK_INODE_INSTANT)
1873 goto unlockandout;
1874
1875 sbp = inode->i_sb;
1876 sbsp = sbp->s_security;
1877 /*
1878 * We're going to use the superblock default label
1879 * if there's no label on the file.
1880 */
1881 final = sbsp->smk_default;
1882
1883 /*
1884 * This is pretty hackish.
1885 * Casey says that we shouldn't have to do
1886 * file system specific code, but it does help
1887 * with keeping it simple.
1888 */
1889 switch (sbp->s_magic) {
1890 case SMACK_MAGIC:
1891 /*
1892 * Casey says that it's a little embarassing
1893 * that the smack file system doesn't do
1894 * extended attributes.
1895 */
1896 final = smack_known_star.smk_known;
1897 break;
1898 case PIPEFS_MAGIC:
1899 /*
1900 * Casey says pipes are easy (?)
1901 */
1902 final = smack_known_star.smk_known;
1903 break;
1904 case DEVPTS_SUPER_MAGIC:
1905 /*
1906 * devpts seems content with the label of the task.
1907 * Programs that change smack have to treat the
1908 * pty with respect.
1909 */
1910 final = csp;
1911 break;
1912 case SOCKFS_MAGIC:
1913 /*
1914 * Casey says sockets get the smack of the task.
1915 */
1916 final = csp;
1917 break;
1918 case PROC_SUPER_MAGIC:
1919 /*
1920 * Casey says procfs appears not to care.
1921 * The superblock default suffices.
1922 */
1923 break;
1924 case TMPFS_MAGIC:
1925 /*
1926 * Device labels should come from the filesystem,
1927 * but watch out, because they're volitile,
1928 * getting recreated on every reboot.
1929 */
1930 final = smack_known_star.smk_known;
1931 /*
1932 * No break.
1933 *
1934 * If a smack value has been set we want to use it,
1935 * but since tmpfs isn't giving us the opportunity
1936 * to set mount options simulate setting the
1937 * superblock default.
1938 */
1939 default:
1940 /*
1941 * This isn't an understood special case.
1942 * Get the value from the xattr.
1943 *
1944 * No xattr support means, alas, no SMACK label.
1945 * Use the aforeapplied default.
1946 * It would be curious if the label of the task
1947 * does not match that assigned.
1948 */
1949 if (inode->i_op->getxattr == NULL)
1950 break;
1951 /*
1952 * Get the dentry for xattr.
1953 */
1954 if (opt_dentry == NULL) {
1955 dp = d_find_alias(inode);
1956 if (dp == NULL)
1957 break;
1958 } else {
1959 dp = dget(opt_dentry);
1960 if (dp == NULL)
1961 break;
1962 }
1963
1964 fetched = smk_fetch(inode, dp);
1965 if (fetched != NULL)
1966 final = fetched;
1967
1968 dput(dp);
1969 break;
1970 }
1971
1972 if (final == NULL)
1973 isp->smk_inode = csp;
1974 else
1975 isp->smk_inode = final;
1976
1977 isp->smk_flags |= SMK_INODE_INSTANT;
1978
1979 unlockandout:
1980 mutex_unlock(&isp->smk_lock);
1981 return;
1982 }
1983
1984 /**
1985 * smack_getprocattr - Smack process attribute access
1986 * @p: the object task
1987 * @name: the name of the attribute in /proc/.../attr
1988 * @value: where to put the result
1989 *
1990 * Places a copy of the task Smack into value
1991 *
1992 * Returns the length of the smack label or an error code
1993 */
1994 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
1995 {
1996 char *cp;
1997 int slen;
1998
1999 if (strcmp(name, "current") != 0)
2000 return -EINVAL;
2001
2002 cp = kstrdup(p->security, GFP_KERNEL);
2003 if (cp == NULL)
2004 return -ENOMEM;
2005
2006 slen = strlen(cp);
2007 *value = cp;
2008 return slen;
2009 }
2010
2011 /**
2012 * smack_setprocattr - Smack process attribute setting
2013 * @p: the object task
2014 * @name: the name of the attribute in /proc/.../attr
2015 * @value: the value to set
2016 * @size: the size of the value
2017 *
2018 * Sets the Smack value of the task. Only setting self
2019 * is permitted and only with privilege
2020 *
2021 * Returns the length of the smack label or an error code
2022 */
2023 static int smack_setprocattr(struct task_struct *p, char *name,
2024 void *value, size_t size)
2025 {
2026 char *newsmack;
2027
2028 if (!__capable(p, CAP_MAC_ADMIN))
2029 return -EPERM;
2030
2031 /*
2032 * Changing another process' Smack value is too dangerous
2033 * and supports no sane use case.
2034 */
2035 if (p != current)
2036 return -EPERM;
2037
2038 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2039 return -EINVAL;
2040
2041 if (strcmp(name, "current") != 0)
2042 return -EINVAL;
2043
2044 newsmack = smk_import(value, size);
2045 if (newsmack == NULL)
2046 return -EINVAL;
2047
2048 p->security = newsmack;
2049 return size;
2050 }
2051
2052 /**
2053 * smack_unix_stream_connect - Smack access on UDS
2054 * @sock: one socket
2055 * @other: the other socket
2056 * @newsk: unused
2057 *
2058 * Return 0 if a subject with the smack of sock could access
2059 * an object with the smack of other, otherwise an error code
2060 */
2061 static int smack_unix_stream_connect(struct socket *sock,
2062 struct socket *other, struct sock *newsk)
2063 {
2064 struct inode *sp = SOCK_INODE(sock);
2065 struct inode *op = SOCK_INODE(other);
2066
2067 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE);
2068 }
2069
2070 /**
2071 * smack_unix_may_send - Smack access on UDS
2072 * @sock: one socket
2073 * @other: the other socket
2074 *
2075 * Return 0 if a subject with the smack of sock could access
2076 * an object with the smack of other, otherwise an error code
2077 */
2078 static int smack_unix_may_send(struct socket *sock, struct socket *other)
2079 {
2080 struct inode *sp = SOCK_INODE(sock);
2081 struct inode *op = SOCK_INODE(other);
2082
2083 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE);
2084 }
2085
2086 /**
2087 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat
2088 * pair to smack
2089 * @sap: netlabel secattr
2090 * @sip: where to put the result
2091 *
2092 * Copies a smack label into sip
2093 */
2094 static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2095 {
2096 char smack[SMK_LABELLEN];
2097 int pcat;
2098
2099 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) == 0) {
2100 /*
2101 * If there are flags but no level netlabel isn't
2102 * behaving the way we expect it to.
2103 *
2104 * Without guidance regarding the smack value
2105 * for the packet fall back on the network
2106 * ambient value.
2107 */
2108 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
2109 return;
2110 }
2111 /*
2112 * Get the categories, if any
2113 */
2114 memset(smack, '\0', SMK_LABELLEN);
2115 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2116 for (pcat = -1;;) {
2117 pcat = netlbl_secattr_catmap_walk(sap->attr.mls.cat,
2118 pcat + 1);
2119 if (pcat < 0)
2120 break;
2121 smack_catset_bit(pcat, smack);
2122 }
2123 /*
2124 * If it is CIPSO using smack direct mapping
2125 * we are already done. WeeHee.
2126 */
2127 if (sap->attr.mls.lvl == smack_cipso_direct) {
2128 memcpy(sip, smack, SMK_MAXLEN);
2129 return;
2130 }
2131 /*
2132 * Look it up in the supplied table if it is not a direct mapping.
2133 */
2134 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
2135 return;
2136 }
2137
2138 /**
2139 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2140 * @sk: socket
2141 * @skb: packet
2142 *
2143 * Returns 0 if the packet should be delivered, an error code otherwise
2144 */
2145 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2146 {
2147 struct netlbl_lsm_secattr secattr;
2148 struct socket_smack *ssp = sk->sk_security;
2149 char smack[SMK_LABELLEN];
2150 int rc;
2151
2152 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2153 return 0;
2154
2155 /*
2156 * Translate what netlabel gave us.
2157 */
2158 memset(smack, '\0', SMK_LABELLEN);
2159 netlbl_secattr_init(&secattr);
2160 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
2161 if (rc == 0)
2162 smack_from_secattr(&secattr, smack);
2163 else
2164 strncpy(smack, smack_net_ambient, SMK_MAXLEN);
2165 netlbl_secattr_destroy(&secattr);
2166 /*
2167 * Receiving a packet requires that the other end
2168 * be able to write here. Read access is not required.
2169 * This is the simplist possible security model
2170 * for networking.
2171 */
2172 return smk_access(smack, ssp->smk_in, MAY_WRITE);
2173 }
2174
2175 /**
2176 * smack_socket_getpeersec_stream - pull in packet label
2177 * @sock: the socket
2178 * @optval: user's destination
2179 * @optlen: size thereof
2180 * @len: max thereoe
2181 *
2182 * returns zero on success, an error code otherwise
2183 */
2184 static int smack_socket_getpeersec_stream(struct socket *sock,
2185 char __user *optval,
2186 int __user *optlen, unsigned len)
2187 {
2188 struct socket_smack *ssp;
2189 int slen;
2190 int rc = 0;
2191
2192 ssp = sock->sk->sk_security;
2193 slen = strlen(ssp->smk_packet) + 1;
2194
2195 if (slen > len)
2196 rc = -ERANGE;
2197 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2198 rc = -EFAULT;
2199
2200 if (put_user(slen, optlen) != 0)
2201 rc = -EFAULT;
2202
2203 return rc;
2204 }
2205
2206
2207 /**
2208 * smack_socket_getpeersec_dgram - pull in packet label
2209 * @sock: the socket
2210 * @skb: packet data
2211 * @secid: pointer to where to put the secid of the packet
2212 *
2213 * Sets the netlabel socket state on sk from parent
2214 */
2215 static int smack_socket_getpeersec_dgram(struct socket *sock,
2216 struct sk_buff *skb, u32 *secid)
2217
2218 {
2219 struct netlbl_lsm_secattr secattr;
2220 struct sock *sk;
2221 char smack[SMK_LABELLEN];
2222 int family = PF_INET;
2223 u32 s;
2224 int rc;
2225
2226 /*
2227 * Only works for families with packets.
2228 */
2229 if (sock != NULL) {
2230 sk = sock->sk;
2231 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2232 return 0;
2233 family = sk->sk_family;
2234 }
2235 /*
2236 * Translate what netlabel gave us.
2237 */
2238 memset(smack, '\0', SMK_LABELLEN);
2239 netlbl_secattr_init(&secattr);
2240 rc = netlbl_skbuff_getattr(skb, family, &secattr);
2241 if (rc == 0)
2242 smack_from_secattr(&secattr, smack);
2243 netlbl_secattr_destroy(&secattr);
2244
2245 /*
2246 * Give up if we couldn't get anything
2247 */
2248 if (rc != 0)
2249 return rc;
2250
2251 s = smack_to_secid(smack);
2252 if (s == 0)
2253 return -EINVAL;
2254
2255 *secid = s;
2256 return 0;
2257 }
2258
2259 /**
2260 * smack_sock_graft - graft access state between two sockets
2261 * @sk: fresh sock
2262 * @parent: donor socket
2263 *
2264 * Sets the netlabel socket state on sk from parent
2265 */
2266 static void smack_sock_graft(struct sock *sk, struct socket *parent)
2267 {
2268 struct socket_smack *ssp;
2269 int rc;
2270
2271 if (sk == NULL)
2272 return;
2273
2274 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2275 return;
2276
2277 ssp = sk->sk_security;
2278 ssp->smk_in = current->security;
2279 ssp->smk_out = current->security;
2280 ssp->smk_packet[0] = '\0';
2281
2282 rc = smack_netlabel(sk);
2283 if (rc != 0)
2284 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
2285 __func__, -rc);
2286 }
2287
2288 /**
2289 * smack_inet_conn_request - Smack access check on connect
2290 * @sk: socket involved
2291 * @skb: packet
2292 * @req: unused
2293 *
2294 * Returns 0 if a task with the packet label could write to
2295 * the socket, otherwise an error code
2296 */
2297 static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
2298 struct request_sock *req)
2299 {
2300 struct netlbl_lsm_secattr skb_secattr;
2301 struct socket_smack *ssp = sk->sk_security;
2302 char smack[SMK_LABELLEN];
2303 int rc;
2304
2305 if (skb == NULL)
2306 return -EACCES;
2307
2308 memset(smack, '\0', SMK_LABELLEN);
2309 netlbl_secattr_init(&skb_secattr);
2310 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr);
2311 if (rc == 0)
2312 smack_from_secattr(&skb_secattr, smack);
2313 else
2314 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
2315 netlbl_secattr_destroy(&skb_secattr);
2316 /*
2317 * Receiving a packet requires that the other end
2318 * be able to write here. Read access is not required.
2319 *
2320 * If the request is successful save the peer's label
2321 * so that SO_PEERCRED can report it.
2322 */
2323 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2324 if (rc == 0)
2325 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
2326
2327 return rc;
2328 }
2329
2330 /*
2331 * Key management security hooks
2332 *
2333 * Casey has not tested key support very heavily.
2334 * The permission check is most likely too restrictive.
2335 * If you care about keys please have a look.
2336 */
2337 #ifdef CONFIG_KEYS
2338
2339 /**
2340 * smack_key_alloc - Set the key security blob
2341 * @key: object
2342 * @tsk: the task associated with the key
2343 * @flags: unused
2344 *
2345 * No allocation required
2346 *
2347 * Returns 0
2348 */
2349 static int smack_key_alloc(struct key *key, struct task_struct *tsk,
2350 unsigned long flags)
2351 {
2352 key->security = tsk->security;
2353 return 0;
2354 }
2355
2356 /**
2357 * smack_key_free - Clear the key security blob
2358 * @key: the object
2359 *
2360 * Clear the blob pointer
2361 */
2362 static void smack_key_free(struct key *key)
2363 {
2364 key->security = NULL;
2365 }
2366
2367 /*
2368 * smack_key_permission - Smack access on a key
2369 * @key_ref: gets to the object
2370 * @context: task involved
2371 * @perm: unused
2372 *
2373 * Return 0 if the task has read and write to the object,
2374 * an error code otherwise
2375 */
2376 static int smack_key_permission(key_ref_t key_ref,
2377 struct task_struct *context, key_perm_t perm)
2378 {
2379 struct key *keyp;
2380
2381 keyp = key_ref_to_ptr(key_ref);
2382 if (keyp == NULL)
2383 return -EINVAL;
2384 /*
2385 * If the key hasn't been initialized give it access so that
2386 * it may do so.
2387 */
2388 if (keyp->security == NULL)
2389 return 0;
2390 /*
2391 * This should not occur
2392 */
2393 if (context->security == NULL)
2394 return -EACCES;
2395
2396 return smk_access(context->security, keyp->security, MAY_READWRITE);
2397 }
2398 #endif /* CONFIG_KEYS */
2399
2400 /*
2401 * Smack Audit hooks
2402 *
2403 * Audit requires a unique representation of each Smack specific
2404 * rule. This unique representation is used to distinguish the
2405 * object to be audited from remaining kernel objects and also
2406 * works as a glue between the audit hooks.
2407 *
2408 * Since repository entries are added but never deleted, we'll use
2409 * the smack_known label address related to the given audit rule as
2410 * the needed unique representation. This also better fits the smack
2411 * model where nearly everything is a label.
2412 */
2413 #ifdef CONFIG_AUDIT
2414
2415 /**
2416 * smack_audit_rule_init - Initialize a smack audit rule
2417 * @field: audit rule fields given from user-space (audit.h)
2418 * @op: required testing operator (=, !=, >, <, ...)
2419 * @rulestr: smack label to be audited
2420 * @vrule: pointer to save our own audit rule representation
2421 *
2422 * Prepare to audit cases where (@field @op @rulestr) is true.
2423 * The label to be audited is created if necessay.
2424 */
2425 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2426 {
2427 char **rule = (char **)vrule;
2428 *rule = NULL;
2429
2430 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2431 return -EINVAL;
2432
2433 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2434 return -EINVAL;
2435
2436 *rule = smk_import(rulestr, 0);
2437
2438 return 0;
2439 }
2440
2441 /**
2442 * smack_audit_rule_known - Distinguish Smack audit rules
2443 * @krule: rule of interest, in Audit kernel representation format
2444 *
2445 * This is used to filter Smack rules from remaining Audit ones.
2446 * If it's proved that this rule belongs to us, the
2447 * audit_rule_match hook will be called to do the final judgement.
2448 */
2449 static int smack_audit_rule_known(struct audit_krule *krule)
2450 {
2451 struct audit_field *f;
2452 int i;
2453
2454 for (i = 0; i < krule->field_count; i++) {
2455 f = &krule->fields[i];
2456
2457 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
2458 return 1;
2459 }
2460
2461 return 0;
2462 }
2463
2464 /**
2465 * smack_audit_rule_match - Audit given object ?
2466 * @secid: security id for identifying the object to test
2467 * @field: audit rule flags given from user-space
2468 * @op: required testing operator
2469 * @vrule: smack internal rule presentation
2470 * @actx: audit context associated with the check
2471 *
2472 * The core Audit hook. It's used to take the decision of
2473 * whether to audit or not to audit a given object.
2474 */
2475 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
2476 struct audit_context *actx)
2477 {
2478 char *smack;
2479 char *rule = vrule;
2480
2481 if (!rule) {
2482 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
2483 "Smack: missing rule\n");
2484 return -ENOENT;
2485 }
2486
2487 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2488 return 0;
2489
2490 smack = smack_from_secid(secid);
2491
2492 /*
2493 * No need to do string comparisons. If a match occurs,
2494 * both pointers will point to the same smack_known
2495 * label.
2496 */
2497 if (op == AUDIT_EQUAL)
2498 return (rule == smack);
2499 if (op == AUDIT_NOT_EQUAL)
2500 return (rule != smack);
2501
2502 return 0;
2503 }
2504
2505 /**
2506 * smack_audit_rule_free - free smack rule representation
2507 * @vrule: rule to be freed.
2508 *
2509 * No memory was allocated.
2510 */
2511 static void smack_audit_rule_free(void *vrule)
2512 {
2513 /* No-op */
2514 }
2515
2516 #endif /* CONFIG_AUDIT */
2517
2518 /*
2519 * smack_secid_to_secctx - return the smack label for a secid
2520 * @secid: incoming integer
2521 * @secdata: destination
2522 * @seclen: how long it is
2523 *
2524 * Exists for networking code.
2525 */
2526 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
2527 {
2528 char *sp = smack_from_secid(secid);
2529
2530 *secdata = sp;
2531 *seclen = strlen(sp);
2532 return 0;
2533 }
2534
2535 /*
2536 * smack_secctx_to_secid - return the secid for a smack label
2537 * @secdata: smack label
2538 * @seclen: how long result is
2539 * @secid: outgoing integer
2540 *
2541 * Exists for audit and networking code.
2542 */
2543 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
2544 {
2545 *secid = smack_to_secid(secdata);
2546 return 0;
2547 }
2548
2549 /*
2550 * smack_release_secctx - don't do anything.
2551 * @key_ref: unused
2552 * @context: unused
2553 * @perm: unused
2554 *
2555 * Exists to make sure nothing gets done, and properly
2556 */
2557 static void smack_release_secctx(char *secdata, u32 seclen)
2558 {
2559 }
2560
2561 struct security_operations smack_ops = {
2562 .name = "smack",
2563
2564 .ptrace = smack_ptrace,
2565 .capget = cap_capget,
2566 .capset_check = cap_capset_check,
2567 .capset_set = cap_capset_set,
2568 .capable = cap_capable,
2569 .syslog = smack_syslog,
2570 .settime = cap_settime,
2571 .vm_enough_memory = cap_vm_enough_memory,
2572
2573 .bprm_apply_creds = cap_bprm_apply_creds,
2574 .bprm_set_security = cap_bprm_set_security,
2575 .bprm_secureexec = cap_bprm_secureexec,
2576
2577 .sb_alloc_security = smack_sb_alloc_security,
2578 .sb_free_security = smack_sb_free_security,
2579 .sb_copy_data = smack_sb_copy_data,
2580 .sb_kern_mount = smack_sb_kern_mount,
2581 .sb_statfs = smack_sb_statfs,
2582 .sb_mount = smack_sb_mount,
2583 .sb_umount = smack_sb_umount,
2584
2585 .inode_alloc_security = smack_inode_alloc_security,
2586 .inode_free_security = smack_inode_free_security,
2587 .inode_init_security = smack_inode_init_security,
2588 .inode_link = smack_inode_link,
2589 .inode_unlink = smack_inode_unlink,
2590 .inode_rmdir = smack_inode_rmdir,
2591 .inode_rename = smack_inode_rename,
2592 .inode_permission = smack_inode_permission,
2593 .inode_setattr = smack_inode_setattr,
2594 .inode_getattr = smack_inode_getattr,
2595 .inode_setxattr = smack_inode_setxattr,
2596 .inode_post_setxattr = smack_inode_post_setxattr,
2597 .inode_getxattr = smack_inode_getxattr,
2598 .inode_removexattr = smack_inode_removexattr,
2599 .inode_need_killpriv = cap_inode_need_killpriv,
2600 .inode_killpriv = cap_inode_killpriv,
2601 .inode_getsecurity = smack_inode_getsecurity,
2602 .inode_setsecurity = smack_inode_setsecurity,
2603 .inode_listsecurity = smack_inode_listsecurity,
2604 .inode_getsecid = smack_inode_getsecid,
2605
2606 .file_permission = smack_file_permission,
2607 .file_alloc_security = smack_file_alloc_security,
2608 .file_free_security = smack_file_free_security,
2609 .file_ioctl = smack_file_ioctl,
2610 .file_lock = smack_file_lock,
2611 .file_fcntl = smack_file_fcntl,
2612 .file_set_fowner = smack_file_set_fowner,
2613 .file_send_sigiotask = smack_file_send_sigiotask,
2614 .file_receive = smack_file_receive,
2615
2616 .task_alloc_security = smack_task_alloc_security,
2617 .task_free_security = smack_task_free_security,
2618 .task_post_setuid = cap_task_post_setuid,
2619 .task_setpgid = smack_task_setpgid,
2620 .task_getpgid = smack_task_getpgid,
2621 .task_getsid = smack_task_getsid,
2622 .task_getsecid = smack_task_getsecid,
2623 .task_setnice = smack_task_setnice,
2624 .task_setioprio = smack_task_setioprio,
2625 .task_getioprio = smack_task_getioprio,
2626 .task_setscheduler = smack_task_setscheduler,
2627 .task_getscheduler = smack_task_getscheduler,
2628 .task_movememory = smack_task_movememory,
2629 .task_kill = smack_task_kill,
2630 .task_wait = smack_task_wait,
2631 .task_reparent_to_init = cap_task_reparent_to_init,
2632 .task_to_inode = smack_task_to_inode,
2633 .task_prctl = cap_task_prctl,
2634
2635 .ipc_permission = smack_ipc_permission,
2636 .ipc_getsecid = smack_ipc_getsecid,
2637
2638 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
2639 .msg_msg_free_security = smack_msg_msg_free_security,
2640
2641 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
2642 .msg_queue_free_security = smack_msg_queue_free_security,
2643 .msg_queue_associate = smack_msg_queue_associate,
2644 .msg_queue_msgctl = smack_msg_queue_msgctl,
2645 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
2646 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
2647
2648 .shm_alloc_security = smack_shm_alloc_security,
2649 .shm_free_security = smack_shm_free_security,
2650 .shm_associate = smack_shm_associate,
2651 .shm_shmctl = smack_shm_shmctl,
2652 .shm_shmat = smack_shm_shmat,
2653
2654 .sem_alloc_security = smack_sem_alloc_security,
2655 .sem_free_security = smack_sem_free_security,
2656 .sem_associate = smack_sem_associate,
2657 .sem_semctl = smack_sem_semctl,
2658 .sem_semop = smack_sem_semop,
2659
2660 .netlink_send = cap_netlink_send,
2661 .netlink_recv = cap_netlink_recv,
2662
2663 .register_security = smack_register_security,
2664
2665 .d_instantiate = smack_d_instantiate,
2666
2667 .getprocattr = smack_getprocattr,
2668 .setprocattr = smack_setprocattr,
2669
2670 .unix_stream_connect = smack_unix_stream_connect,
2671 .unix_may_send = smack_unix_may_send,
2672
2673 .socket_post_create = smack_socket_post_create,
2674 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
2675 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
2676 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
2677 .sk_alloc_security = smack_sk_alloc_security,
2678 .sk_free_security = smack_sk_free_security,
2679 .sock_graft = smack_sock_graft,
2680 .inet_conn_request = smack_inet_conn_request,
2681
2682 /* key management security hooks */
2683 #ifdef CONFIG_KEYS
2684 .key_alloc = smack_key_alloc,
2685 .key_free = smack_key_free,
2686 .key_permission = smack_key_permission,
2687 #endif /* CONFIG_KEYS */
2688
2689 /* Audit hooks */
2690 #ifdef CONFIG_AUDIT
2691 .audit_rule_init = smack_audit_rule_init,
2692 .audit_rule_known = smack_audit_rule_known,
2693 .audit_rule_match = smack_audit_rule_match,
2694 .audit_rule_free = smack_audit_rule_free,
2695 #endif /* CONFIG_AUDIT */
2696
2697 .secid_to_secctx = smack_secid_to_secctx,
2698 .secctx_to_secid = smack_secctx_to_secid,
2699 .release_secctx = smack_release_secctx,
2700 };
2701
2702 /**
2703 * smack_init - initialize the smack system
2704 *
2705 * Returns 0
2706 */
2707 static __init int smack_init(void)
2708 {
2709 if (!security_module_enable(&smack_ops))
2710 return 0;
2711
2712 printk(KERN_INFO "Smack: Initializing.\n");
2713
2714 /*
2715 * Set the security state for the initial task.
2716 */
2717 current->security = &smack_known_floor.smk_known;
2718
2719 /*
2720 * Initialize locks
2721 */
2722 spin_lock_init(&smack_known_unset.smk_cipsolock);
2723 spin_lock_init(&smack_known_huh.smk_cipsolock);
2724 spin_lock_init(&smack_known_hat.smk_cipsolock);
2725 spin_lock_init(&smack_known_star.smk_cipsolock);
2726 spin_lock_init(&smack_known_floor.smk_cipsolock);
2727 spin_lock_init(&smack_known_invalid.smk_cipsolock);
2728
2729 /*
2730 * Register with LSM
2731 */
2732 if (register_security(&smack_ops))
2733 panic("smack: Unable to register with kernel.\n");
2734
2735 return 0;
2736 }
2737
2738 /*
2739 * Smack requires early initialization in order to label
2740 * all processes and objects when they are created.
2741 */
2742 security_initcall(smack_init);
2743