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1/*
2 * Simplified MAC Kernel (smack) security module
3 *
4 * This file contains the smack hook function implementations.
5 *
6 * Authors:
7 * Casey Schaufler <casey@schaufler-ca.com>
8 * Jarkko Sakkinen <ext-jarkko.2.sakkinen@nokia.com>
9 *
10 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
11 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
12 * Paul Moore <paul@paul-moore.com>
13 * Copyright (C) 2010 Nokia Corporation
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License version 2,
17 * as published by the Free Software Foundation.
18 */
19
20#include <linux/xattr.h>
21#include <linux/pagemap.h>
22#include <linux/mount.h>
23#include <linux/stat.h>
24#include <linux/kd.h>
25#include <asm/ioctls.h>
26#include <linux/ip.h>
27#include <linux/tcp.h>
28#include <linux/udp.h>
29#include <linux/slab.h>
30#include <linux/mutex.h>
31#include <linux/pipe_fs_i.h>
32#include <net/netlabel.h>
33#include <net/cipso_ipv4.h>
34#include <linux/audit.h>
35#include <linux/magic.h>
36#include <linux/dcache.h>
37#include "smack.h"
38
39#define task_security(task) (task_cred_xxx((task), security))
40
41#define TRANS_TRUE "TRUE"
42#define TRANS_TRUE_SIZE 4
43
44/**
45 * smk_fetch - Fetch the smack label from a file.
46 * @ip: a pointer to the inode
47 * @dp: a pointer to the dentry
48 *
49 * Returns a pointer to the master list entry for the Smack label
50 * or NULL if there was no label to fetch.
51 */
52static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp)
53{
54 int rc;
55 char in[SMK_LABELLEN];
56
57 if (ip->i_op->getxattr == NULL)
58 return NULL;
59
60 rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN);
61 if (rc < 0)
62 return NULL;
63
64 return smk_import(in, rc);
65}
66
67/**
68 * new_inode_smack - allocate an inode security blob
69 * @smack: a pointer to the Smack label to use in the blob
70 *
71 * Returns the new blob or NULL if there's no memory available
72 */
73struct inode_smack *new_inode_smack(char *smack)
74{
75 struct inode_smack *isp;
76
77 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
78 if (isp == NULL)
79 return NULL;
80
81 isp->smk_inode = smack;
82 isp->smk_flags = 0;
83 mutex_init(&isp->smk_lock);
84
85 return isp;
86}
87
88/**
89 * new_task_smack - allocate a task security blob
90 * @smack: a pointer to the Smack label to use in the blob
91 *
92 * Returns the new blob or NULL if there's no memory available
93 */
94static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp)
95{
96 struct task_smack *tsp;
97
98 tsp = kzalloc(sizeof(struct task_smack), gfp);
99 if (tsp == NULL)
100 return NULL;
101
102 tsp->smk_task = task;
103 tsp->smk_forked = forked;
104 INIT_LIST_HEAD(&tsp->smk_rules);
105 mutex_init(&tsp->smk_rules_lock);
106
107 return tsp;
108}
109
110/**
111 * smk_copy_rules - copy a rule set
112 * @nhead - new rules header pointer
113 * @ohead - old rules header pointer
114 *
115 * Returns 0 on success, -ENOMEM on error
116 */
117static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
118 gfp_t gfp)
119{
120 struct smack_rule *nrp;
121 struct smack_rule *orp;
122 int rc = 0;
123
124 INIT_LIST_HEAD(nhead);
125
126 list_for_each_entry_rcu(orp, ohead, list) {
127 nrp = kzalloc(sizeof(struct smack_rule), gfp);
128 if (nrp == NULL) {
129 rc = -ENOMEM;
130 break;
131 }
132 *nrp = *orp;
133 list_add_rcu(&nrp->list, nhead);
134 }
135 return rc;
136}
137
138/*
139 * LSM hooks.
140 * We he, that is fun!
141 */
142
143/**
144 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
145 * @ctp: child task pointer
146 * @mode: ptrace attachment mode
147 *
148 * Returns 0 if access is OK, an error code otherwise
149 *
150 * Do the capability checks, and require read and write.
151 */
152static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
153{
154 int rc;
155 struct smk_audit_info ad;
156 char *tsp;
157
158 rc = cap_ptrace_access_check(ctp, mode);
159 if (rc != 0)
160 return rc;
161
162 tsp = smk_of_task(task_security(ctp));
163 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
164 smk_ad_setfield_u_tsk(&ad, ctp);
165
166 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
167 return rc;
168}
169
170/**
171 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
172 * @ptp: parent task pointer
173 *
174 * Returns 0 if access is OK, an error code otherwise
175 *
176 * Do the capability checks, and require read and write.
177 */
178static int smack_ptrace_traceme(struct task_struct *ptp)
179{
180 int rc;
181 struct smk_audit_info ad;
182 char *tsp;
183
184 rc = cap_ptrace_traceme(ptp);
185 if (rc != 0)
186 return rc;
187
188 tsp = smk_of_task(task_security(ptp));
189 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
190 smk_ad_setfield_u_tsk(&ad, ptp);
191
192 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
193 return rc;
194}
195
196/**
197 * smack_syslog - Smack approval on syslog
198 * @type: message type
199 *
200 * Require that the task has the floor label
201 *
202 * Returns 0 on success, error code otherwise.
203 */
204static int smack_syslog(int typefrom_file)
205{
206 int rc = 0;
207 char *sp = smk_of_current();
208
209 if (capable(CAP_MAC_OVERRIDE))
210 return 0;
211
212 if (sp != smack_known_floor.smk_known)
213 rc = -EACCES;
214
215 return rc;
216}
217
218
219/*
220 * Superblock Hooks.
221 */
222
223/**
224 * smack_sb_alloc_security - allocate a superblock blob
225 * @sb: the superblock getting the blob
226 *
227 * Returns 0 on success or -ENOMEM on error.
228 */
229static int smack_sb_alloc_security(struct super_block *sb)
230{
231 struct superblock_smack *sbsp;
232
233 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
234
235 if (sbsp == NULL)
236 return -ENOMEM;
237
238 sbsp->smk_root = smack_known_floor.smk_known;
239 sbsp->smk_default = smack_known_floor.smk_known;
240 sbsp->smk_floor = smack_known_floor.smk_known;
241 sbsp->smk_hat = smack_known_hat.smk_known;
242 sbsp->smk_initialized = 0;
243 spin_lock_init(&sbsp->smk_sblock);
244
245 sb->s_security = sbsp;
246
247 return 0;
248}
249
250/**
251 * smack_sb_free_security - free a superblock blob
252 * @sb: the superblock getting the blob
253 *
254 */
255static void smack_sb_free_security(struct super_block *sb)
256{
257 kfree(sb->s_security);
258 sb->s_security = NULL;
259}
260
261/**
262 * smack_sb_copy_data - copy mount options data for processing
263 * @orig: where to start
264 * @smackopts: mount options string
265 *
266 * Returns 0 on success or -ENOMEM on error.
267 *
268 * Copy the Smack specific mount options out of the mount
269 * options list.
270 */
271static int smack_sb_copy_data(char *orig, char *smackopts)
272{
273 char *cp, *commap, *otheropts, *dp;
274
275 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
276 if (otheropts == NULL)
277 return -ENOMEM;
278
279 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
280 if (strstr(cp, SMK_FSDEFAULT) == cp)
281 dp = smackopts;
282 else if (strstr(cp, SMK_FSFLOOR) == cp)
283 dp = smackopts;
284 else if (strstr(cp, SMK_FSHAT) == cp)
285 dp = smackopts;
286 else if (strstr(cp, SMK_FSROOT) == cp)
287 dp = smackopts;
288 else
289 dp = otheropts;
290
291 commap = strchr(cp, ',');
292 if (commap != NULL)
293 *commap = '\0';
294
295 if (*dp != '\0')
296 strcat(dp, ",");
297 strcat(dp, cp);
298 }
299
300 strcpy(orig, otheropts);
301 free_page((unsigned long)otheropts);
302
303 return 0;
304}
305
306/**
307 * smack_sb_kern_mount - Smack specific mount processing
308 * @sb: the file system superblock
309 * @flags: the mount flags
310 * @data: the smack mount options
311 *
312 * Returns 0 on success, an error code on failure
313 */
314static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
315{
316 struct dentry *root = sb->s_root;
317 struct inode *inode = root->d_inode;
318 struct superblock_smack *sp = sb->s_security;
319 struct inode_smack *isp;
320 char *op;
321 char *commap;
322 char *nsp;
323
324 spin_lock(&sp->smk_sblock);
325 if (sp->smk_initialized != 0) {
326 spin_unlock(&sp->smk_sblock);
327 return 0;
328 }
329 sp->smk_initialized = 1;
330 spin_unlock(&sp->smk_sblock);
331
332 for (op = data; op != NULL; op = commap) {
333 commap = strchr(op, ',');
334 if (commap != NULL)
335 *commap++ = '\0';
336
337 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
338 op += strlen(SMK_FSHAT);
339 nsp = smk_import(op, 0);
340 if (nsp != NULL)
341 sp->smk_hat = nsp;
342 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
343 op += strlen(SMK_FSFLOOR);
344 nsp = smk_import(op, 0);
345 if (nsp != NULL)
346 sp->smk_floor = nsp;
347 } else if (strncmp(op, SMK_FSDEFAULT,
348 strlen(SMK_FSDEFAULT)) == 0) {
349 op += strlen(SMK_FSDEFAULT);
350 nsp = smk_import(op, 0);
351 if (nsp != NULL)
352 sp->smk_default = nsp;
353 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
354 op += strlen(SMK_FSROOT);
355 nsp = smk_import(op, 0);
356 if (nsp != NULL)
357 sp->smk_root = nsp;
358 }
359 }
360
361 /*
362 * Initialize the root inode.
363 */
364 isp = inode->i_security;
365 if (isp == NULL)
366 inode->i_security = new_inode_smack(sp->smk_root);
367 else
368 isp->smk_inode = sp->smk_root;
369
370 return 0;
371}
372
373/**
374 * smack_sb_statfs - Smack check on statfs
375 * @dentry: identifies the file system in question
376 *
377 * Returns 0 if current can read the floor of the filesystem,
378 * and error code otherwise
379 */
380static int smack_sb_statfs(struct dentry *dentry)
381{
382 struct superblock_smack *sbp = dentry->d_sb->s_security;
383 int rc;
384 struct smk_audit_info ad;
385
386 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
387 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
388
389 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
390 return rc;
391}
392
393/**
394 * smack_sb_mount - Smack check for mounting
395 * @dev_name: unused
396 * @path: mount point
397 * @type: unused
398 * @flags: unused
399 * @data: unused
400 *
401 * Returns 0 if current can write the floor of the filesystem
402 * being mounted on, an error code otherwise.
403 */
404static int smack_sb_mount(char *dev_name, struct path *path,
405 char *type, unsigned long flags, void *data)
406{
407 struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
408 struct smk_audit_info ad;
409
410 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
411 smk_ad_setfield_u_fs_path(&ad, *path);
412
413 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
414}
415
416/**
417 * smack_sb_umount - Smack check for unmounting
418 * @mnt: file system to unmount
419 * @flags: unused
420 *
421 * Returns 0 if current can write the floor of the filesystem
422 * being unmounted, an error code otherwise.
423 */
424static int smack_sb_umount(struct vfsmount *mnt, int flags)
425{
426 struct superblock_smack *sbp;
427 struct smk_audit_info ad;
428 struct path path;
429
430 path.dentry = mnt->mnt_root;
431 path.mnt = mnt;
432
433 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
434 smk_ad_setfield_u_fs_path(&ad, path);
435
436 sbp = mnt->mnt_sb->s_security;
437 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
438}
439
440/*
441 * BPRM hooks
442 */
443
444static int smack_bprm_set_creds(struct linux_binprm *bprm)
445{
446 struct task_smack *tsp = bprm->cred->security;
447 struct inode_smack *isp;
448 struct dentry *dp;
449 int rc;
450
451 rc = cap_bprm_set_creds(bprm);
452 if (rc != 0)
453 return rc;
454
455 if (bprm->cred_prepared)
456 return 0;
457
458 if (bprm->file == NULL || bprm->file->f_dentry == NULL)
459 return 0;
460
461 dp = bprm->file->f_dentry;
462
463 if (dp->d_inode == NULL)
464 return 0;
465
466 isp = dp->d_inode->i_security;
467
468 if (isp->smk_task != NULL)
469 tsp->smk_task = isp->smk_task;
470
471 return 0;
472}
473
474/*
475 * Inode hooks
476 */
477
478/**
479 * smack_inode_alloc_security - allocate an inode blob
480 * @inode: the inode in need of a blob
481 *
482 * Returns 0 if it gets a blob, -ENOMEM otherwise
483 */
484static int smack_inode_alloc_security(struct inode *inode)
485{
486 inode->i_security = new_inode_smack(smk_of_current());
487 if (inode->i_security == NULL)
488 return -ENOMEM;
489 return 0;
490}
491
492/**
493 * smack_inode_free_security - free an inode blob
494 * @inode: the inode with a blob
495 *
496 * Clears the blob pointer in inode
497 */
498static void smack_inode_free_security(struct inode *inode)
499{
500 kfree(inode->i_security);
501 inode->i_security = NULL;
502}
503
504/**
505 * smack_inode_init_security - copy out the smack from an inode
506 * @inode: the inode
507 * @dir: unused
508 * @qstr: unused
509 * @name: where to put the attribute name
510 * @value: where to put the attribute value
511 * @len: where to put the length of the attribute
512 *
513 * Returns 0 if it all works out, -ENOMEM if there's no memory
514 */
515static int smack_inode_init_security(struct inode *inode, struct inode *dir,
516 const struct qstr *qstr, char **name,
517 void **value, size_t *len)
518{
519 char *isp = smk_of_inode(inode);
520 char *dsp = smk_of_inode(dir);
521 int may;
522
523 if (name) {
524 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
525 if (*name == NULL)
526 return -ENOMEM;
527 }
528
529 if (value) {
530 rcu_read_lock();
531 may = smk_access_entry(smk_of_current(), dsp, &smack_rule_list);
532 rcu_read_unlock();
533
534 /*
535 * If the access rule allows transmutation and
536 * the directory requests transmutation then
537 * by all means transmute.
538 */
539 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
540 smk_inode_transmutable(dir))
541 isp = dsp;
542
543 *value = kstrdup(isp, GFP_KERNEL);
544 if (*value == NULL)
545 return -ENOMEM;
546 }
547
548 if (len)
549 *len = strlen(isp) + 1;
550
551 return 0;
552}
553
554/**
555 * smack_inode_link - Smack check on link
556 * @old_dentry: the existing object
557 * @dir: unused
558 * @new_dentry: the new object
559 *
560 * Returns 0 if access is permitted, an error code otherwise
561 */
562static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
563 struct dentry *new_dentry)
564{
565 char *isp;
566 struct smk_audit_info ad;
567 int rc;
568
569 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
570 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
571
572 isp = smk_of_inode(old_dentry->d_inode);
573 rc = smk_curacc(isp, MAY_WRITE, &ad);
574
575 if (rc == 0 && new_dentry->d_inode != NULL) {
576 isp = smk_of_inode(new_dentry->d_inode);
577 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
578 rc = smk_curacc(isp, MAY_WRITE, &ad);
579 }
580
581 return rc;
582}
583
584/**
585 * smack_inode_unlink - Smack check on inode deletion
586 * @dir: containing directory object
587 * @dentry: file to unlink
588 *
589 * Returns 0 if current can write the containing directory
590 * and the object, error code otherwise
591 */
592static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
593{
594 struct inode *ip = dentry->d_inode;
595 struct smk_audit_info ad;
596 int rc;
597
598 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
599 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
600
601 /*
602 * You need write access to the thing you're unlinking
603 */
604 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
605 if (rc == 0) {
606 /*
607 * You also need write access to the containing directory
608 */
609 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
610 smk_ad_setfield_u_fs_inode(&ad, dir);
611 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
612 }
613 return rc;
614}
615
616/**
617 * smack_inode_rmdir - Smack check on directory deletion
618 * @dir: containing directory object
619 * @dentry: directory to unlink
620 *
621 * Returns 0 if current can write the containing directory
622 * and the directory, error code otherwise
623 */
624static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
625{
626 struct smk_audit_info ad;
627 int rc;
628
629 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
630 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
631
632 /*
633 * You need write access to the thing you're removing
634 */
635 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
636 if (rc == 0) {
637 /*
638 * You also need write access to the containing directory
639 */
640 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
641 smk_ad_setfield_u_fs_inode(&ad, dir);
642 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
643 }
644
645 return rc;
646}
647
648/**
649 * smack_inode_rename - Smack check on rename
650 * @old_inode: the old directory
651 * @old_dentry: unused
652 * @new_inode: the new directory
653 * @new_dentry: unused
654 *
655 * Read and write access is required on both the old and
656 * new directories.
657 *
658 * Returns 0 if access is permitted, an error code otherwise
659 */
660static int smack_inode_rename(struct inode *old_inode,
661 struct dentry *old_dentry,
662 struct inode *new_inode,
663 struct dentry *new_dentry)
664{
665 int rc;
666 char *isp;
667 struct smk_audit_info ad;
668
669 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
670 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
671
672 isp = smk_of_inode(old_dentry->d_inode);
673 rc = smk_curacc(isp, MAY_READWRITE, &ad);
674
675 if (rc == 0 && new_dentry->d_inode != NULL) {
676 isp = smk_of_inode(new_dentry->d_inode);
677 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
678 rc = smk_curacc(isp, MAY_READWRITE, &ad);
679 }
680 return rc;
681}
682
683/**
684 * smack_inode_permission - Smack version of permission()
685 * @inode: the inode in question
686 * @mask: the access requested
687 *
688 * This is the important Smack hook.
689 *
690 * Returns 0 if access is permitted, -EACCES otherwise
691 */
692static int smack_inode_permission(struct inode *inode, int mask)
693{
694 struct smk_audit_info ad;
695 int no_block = mask & MAY_NOT_BLOCK;
696
697 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
698 /*
699 * No permission to check. Existence test. Yup, it's there.
700 */
701 if (mask == 0)
702 return 0;
703
704 /* May be droppable after audit */
705 if (no_block)
706 return -ECHILD;
707 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
708 smk_ad_setfield_u_fs_inode(&ad, inode);
709 return smk_curacc(smk_of_inode(inode), mask, &ad);
710}
711
712/**
713 * smack_inode_setattr - Smack check for setting attributes
714 * @dentry: the object
715 * @iattr: for the force flag
716 *
717 * Returns 0 if access is permitted, an error code otherwise
718 */
719static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
720{
721 struct smk_audit_info ad;
722 /*
723 * Need to allow for clearing the setuid bit.
724 */
725 if (iattr->ia_valid & ATTR_FORCE)
726 return 0;
727 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
728 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
729
730 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
731}
732
733/**
734 * smack_inode_getattr - Smack check for getting attributes
735 * @mnt: unused
736 * @dentry: the object
737 *
738 * Returns 0 if access is permitted, an error code otherwise
739 */
740static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
741{
742 struct smk_audit_info ad;
743 struct path path;
744
745 path.dentry = dentry;
746 path.mnt = mnt;
747
748 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
749 smk_ad_setfield_u_fs_path(&ad, path);
750 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
751}
752
753/**
754 * smack_inode_setxattr - Smack check for setting xattrs
755 * @dentry: the object
756 * @name: name of the attribute
757 * @value: unused
758 * @size: unused
759 * @flags: unused
760 *
761 * This protects the Smack attribute explicitly.
762 *
763 * Returns 0 if access is permitted, an error code otherwise
764 */
765static int smack_inode_setxattr(struct dentry *dentry, const char *name,
766 const void *value, size_t size, int flags)
767{
768 struct smk_audit_info ad;
769 int rc = 0;
770
771 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
772 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
773 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
774 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
775 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
776 if (!capable(CAP_MAC_ADMIN))
777 rc = -EPERM;
778 /*
779 * check label validity here so import wont fail on
780 * post_setxattr
781 */
782 if (size == 0 || size >= SMK_LABELLEN ||
783 smk_import(value, size) == NULL)
784 rc = -EINVAL;
785 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
786 if (!capable(CAP_MAC_ADMIN))
787 rc = -EPERM;
788 if (size != TRANS_TRUE_SIZE ||
789 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
790 rc = -EINVAL;
791 } else
792 rc = cap_inode_setxattr(dentry, name, value, size, flags);
793
794 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
795 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
796
797 if (rc == 0)
798 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
799
800 return rc;
801}
802
803/**
804 * smack_inode_post_setxattr - Apply the Smack update approved above
805 * @dentry: object
806 * @name: attribute name
807 * @value: attribute value
808 * @size: attribute size
809 * @flags: unused
810 *
811 * Set the pointer in the inode blob to the entry found
812 * in the master label list.
813 */
814static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
815 const void *value, size_t size, int flags)
816{
817 char *nsp;
818 struct inode_smack *isp = dentry->d_inode->i_security;
819
820 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
821 nsp = smk_import(value, size);
822 if (nsp != NULL)
823 isp->smk_inode = nsp;
824 else
825 isp->smk_inode = smack_known_invalid.smk_known;
826 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
827 nsp = smk_import(value, size);
828 if (nsp != NULL)
829 isp->smk_task = nsp;
830 else
831 isp->smk_task = smack_known_invalid.smk_known;
832 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
833 nsp = smk_import(value, size);
834 if (nsp != NULL)
835 isp->smk_mmap = nsp;
836 else
837 isp->smk_mmap = smack_known_invalid.smk_known;
838 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
839 isp->smk_flags |= SMK_INODE_TRANSMUTE;
840
841 return;
842}
843
844/*
845 * smack_inode_getxattr - Smack check on getxattr
846 * @dentry: the object
847 * @name: unused
848 *
849 * Returns 0 if access is permitted, an error code otherwise
850 */
851static int smack_inode_getxattr(struct dentry *dentry, const char *name)
852{
853 struct smk_audit_info ad;
854
855 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
856 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
857
858 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
859}
860
861/*
862 * smack_inode_removexattr - Smack check on removexattr
863 * @dentry: the object
864 * @name: name of the attribute
865 *
866 * Removing the Smack attribute requires CAP_MAC_ADMIN
867 *
868 * Returns 0 if access is permitted, an error code otherwise
869 */
870static int smack_inode_removexattr(struct dentry *dentry, const char *name)
871{
872 struct inode_smack *isp;
873 struct smk_audit_info ad;
874 int rc = 0;
875
876 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
877 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
878 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
879 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
880 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
881 strcmp(name, XATTR_NAME_SMACKMMAP)) {
882 if (!capable(CAP_MAC_ADMIN))
883 rc = -EPERM;
884 } else
885 rc = cap_inode_removexattr(dentry, name);
886
887 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
888 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
889 if (rc == 0)
890 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
891
892 if (rc == 0) {
893 isp = dentry->d_inode->i_security;
894 isp->smk_task = NULL;
895 isp->smk_mmap = NULL;
896 }
897
898 return rc;
899}
900
901/**
902 * smack_inode_getsecurity - get smack xattrs
903 * @inode: the object
904 * @name: attribute name
905 * @buffer: where to put the result
906 * @alloc: unused
907 *
908 * Returns the size of the attribute or an error code
909 */
910static int smack_inode_getsecurity(const struct inode *inode,
911 const char *name, void **buffer,
912 bool alloc)
913{
914 struct socket_smack *ssp;
915 struct socket *sock;
916 struct super_block *sbp;
917 struct inode *ip = (struct inode *)inode;
918 char *isp;
919 int ilen;
920 int rc = 0;
921
922 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
923 isp = smk_of_inode(inode);
924 ilen = strlen(isp) + 1;
925 *buffer = isp;
926 return ilen;
927 }
928
929 /*
930 * The rest of the Smack xattrs are only on sockets.
931 */
932 sbp = ip->i_sb;
933 if (sbp->s_magic != SOCKFS_MAGIC)
934 return -EOPNOTSUPP;
935
936 sock = SOCKET_I(ip);
937 if (sock == NULL || sock->sk == NULL)
938 return -EOPNOTSUPP;
939
940 ssp = sock->sk->sk_security;
941
942 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
943 isp = ssp->smk_in;
944 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
945 isp = ssp->smk_out;
946 else
947 return -EOPNOTSUPP;
948
949 ilen = strlen(isp) + 1;
950 if (rc == 0) {
951 *buffer = isp;
952 rc = ilen;
953 }
954
955 return rc;
956}
957
958
959/**
960 * smack_inode_listsecurity - list the Smack attributes
961 * @inode: the object
962 * @buffer: where they go
963 * @buffer_size: size of buffer
964 *
965 * Returns 0 on success, -EINVAL otherwise
966 */
967static int smack_inode_listsecurity(struct inode *inode, char *buffer,
968 size_t buffer_size)
969{
970 int len = strlen(XATTR_NAME_SMACK);
971
972 if (buffer != NULL && len <= buffer_size) {
973 memcpy(buffer, XATTR_NAME_SMACK, len);
974 return len;
975 }
976 return -EINVAL;
977}
978
979/**
980 * smack_inode_getsecid - Extract inode's security id
981 * @inode: inode to extract the info from
982 * @secid: where result will be saved
983 */
984static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
985{
986 struct inode_smack *isp = inode->i_security;
987
988 *secid = smack_to_secid(isp->smk_inode);
989}
990
991/*
992 * File Hooks
993 */
994
995/**
996 * smack_file_permission - Smack check on file operations
997 * @file: unused
998 * @mask: unused
999 *
1000 * Returns 0
1001 *
1002 * Should access checks be done on each read or write?
1003 * UNICOS and SELinux say yes.
1004 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1005 *
1006 * I'll say no for now. Smack does not do the frequent
1007 * label changing that SELinux does.
1008 */
1009static int smack_file_permission(struct file *file, int mask)
1010{
1011 return 0;
1012}
1013
1014/**
1015 * smack_file_alloc_security - assign a file security blob
1016 * @file: the object
1017 *
1018 * The security blob for a file is a pointer to the master
1019 * label list, so no allocation is done.
1020 *
1021 * Returns 0
1022 */
1023static int smack_file_alloc_security(struct file *file)
1024{
1025 file->f_security = smk_of_current();
1026 return 0;
1027}
1028
1029/**
1030 * smack_file_free_security - clear a file security blob
1031 * @file: the object
1032 *
1033 * The security blob for a file is a pointer to the master
1034 * label list, so no memory is freed.
1035 */
1036static void smack_file_free_security(struct file *file)
1037{
1038 file->f_security = NULL;
1039}
1040
1041/**
1042 * smack_file_ioctl - Smack check on ioctls
1043 * @file: the object
1044 * @cmd: what to do
1045 * @arg: unused
1046 *
1047 * Relies heavily on the correct use of the ioctl command conventions.
1048 *
1049 * Returns 0 if allowed, error code otherwise
1050 */
1051static int smack_file_ioctl(struct file *file, unsigned int cmd,
1052 unsigned long arg)
1053{
1054 int rc = 0;
1055 struct smk_audit_info ad;
1056
1057 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1058 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1059
1060 if (_IOC_DIR(cmd) & _IOC_WRITE)
1061 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1062
1063 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
1064 rc = smk_curacc(file->f_security, MAY_READ, &ad);
1065
1066 return rc;
1067}
1068
1069/**
1070 * smack_file_lock - Smack check on file locking
1071 * @file: the object
1072 * @cmd: unused
1073 *
1074 * Returns 0 if current has write access, error code otherwise
1075 */
1076static int smack_file_lock(struct file *file, unsigned int cmd)
1077{
1078 struct smk_audit_info ad;
1079
1080 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1081 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1082 return smk_curacc(file->f_security, MAY_WRITE, &ad);
1083}
1084
1085/**
1086 * smack_file_fcntl - Smack check on fcntl
1087 * @file: the object
1088 * @cmd: what action to check
1089 * @arg: unused
1090 *
1091 * Returns 0 if current has access, error code otherwise
1092 */
1093static int smack_file_fcntl(struct file *file, unsigned int cmd,
1094 unsigned long arg)
1095{
1096 struct smk_audit_info ad;
1097 int rc;
1098
1099 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1100 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1101
1102 switch (cmd) {
1103 case F_DUPFD:
1104 case F_GETFD:
1105 case F_GETFL:
1106 case F_GETLK:
1107 case F_GETOWN:
1108 case F_GETSIG:
1109 rc = smk_curacc(file->f_security, MAY_READ, &ad);
1110 break;
1111 case F_SETFD:
1112 case F_SETFL:
1113 case F_SETLK:
1114 case F_SETLKW:
1115 case F_SETOWN:
1116 case F_SETSIG:
1117 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1118 break;
1119 default:
1120 rc = smk_curacc(file->f_security, MAY_READWRITE, &ad);
1121 }
1122
1123 return rc;
1124}
1125
1126/**
1127 * smack_file_mmap :
1128 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1129 * if mapping anonymous memory.
1130 * @file contains the file structure for file to map (may be NULL).
1131 * @reqprot contains the protection requested by the application.
1132 * @prot contains the protection that will be applied by the kernel.
1133 * @flags contains the operational flags.
1134 * Return 0 if permission is granted.
1135 */
1136static int smack_file_mmap(struct file *file,
1137 unsigned long reqprot, unsigned long prot,
1138 unsigned long flags, unsigned long addr,
1139 unsigned long addr_only)
1140{
1141 struct smack_rule *srp;
1142 struct task_smack *tsp;
1143 char *sp;
1144 char *msmack;
1145 char *osmack;
1146 struct inode_smack *isp;
1147 struct dentry *dp;
1148 int may;
1149 int mmay;
1150 int tmay;
1151 int rc;
1152
1153 /* do DAC check on address space usage */
1154 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
1155 if (rc || addr_only)
1156 return rc;
1157
1158 if (file == NULL || file->f_dentry == NULL)
1159 return 0;
1160
1161 dp = file->f_dentry;
1162
1163 if (dp->d_inode == NULL)
1164 return 0;
1165
1166 isp = dp->d_inode->i_security;
1167 if (isp->smk_mmap == NULL)
1168 return 0;
1169 msmack = isp->smk_mmap;
1170
1171 tsp = current_security();
1172 sp = smk_of_current();
1173 rc = 0;
1174
1175 rcu_read_lock();
1176 /*
1177 * For each Smack rule associated with the subject
1178 * label verify that the SMACK64MMAP also has access
1179 * to that rule's object label.
1180 *
1181 * Because neither of the labels comes
1182 * from the networking code it is sufficient
1183 * to compare pointers.
1184 */
1185 list_for_each_entry_rcu(srp, &smack_rule_list, list) {
1186 if (srp->smk_subject != sp)
1187 continue;
1188
1189 osmack = srp->smk_object;
1190 /*
1191 * Matching labels always allows access.
1192 */
1193 if (msmack == osmack)
1194 continue;
1195 /*
1196 * If there is a matching local rule take
1197 * that into account as well.
1198 */
1199 may = smk_access_entry(srp->smk_subject, osmack,
1200 &tsp->smk_rules);
1201 if (may == -ENOENT)
1202 may = srp->smk_access;
1203 else
1204 may &= srp->smk_access;
1205 /*
1206 * If may is zero the SMACK64MMAP subject can't
1207 * possibly have less access.
1208 */
1209 if (may == 0)
1210 continue;
1211
1212 /*
1213 * Fetch the global list entry.
1214 * If there isn't one a SMACK64MMAP subject
1215 * can't have as much access as current.
1216 */
1217 mmay = smk_access_entry(msmack, osmack, &smack_rule_list);
1218 if (mmay == -ENOENT) {
1219 rc = -EACCES;
1220 break;
1221 }
1222 /*
1223 * If there is a local entry it modifies the
1224 * potential access, too.
1225 */
1226 tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules);
1227 if (tmay != -ENOENT)
1228 mmay &= tmay;
1229
1230 /*
1231 * If there is any access available to current that is
1232 * not available to a SMACK64MMAP subject
1233 * deny access.
1234 */
1235 if ((may | mmay) != mmay) {
1236 rc = -EACCES;
1237 break;
1238 }
1239 }
1240
1241 rcu_read_unlock();
1242
1243 return rc;
1244}
1245
1246/**
1247 * smack_file_set_fowner - set the file security blob value
1248 * @file: object in question
1249 *
1250 * Returns 0
1251 * Further research may be required on this one.
1252 */
1253static int smack_file_set_fowner(struct file *file)
1254{
1255 file->f_security = smk_of_current();
1256 return 0;
1257}
1258
1259/**
1260 * smack_file_send_sigiotask - Smack on sigio
1261 * @tsk: The target task
1262 * @fown: the object the signal come from
1263 * @signum: unused
1264 *
1265 * Allow a privileged task to get signals even if it shouldn't
1266 *
1267 * Returns 0 if a subject with the object's smack could
1268 * write to the task, an error code otherwise.
1269 */
1270static int smack_file_send_sigiotask(struct task_struct *tsk,
1271 struct fown_struct *fown, int signum)
1272{
1273 struct file *file;
1274 int rc;
1275 char *tsp = smk_of_task(tsk->cred->security);
1276 struct smk_audit_info ad;
1277
1278 /*
1279 * struct fown_struct is never outside the context of a struct file
1280 */
1281 file = container_of(fown, struct file, f_owner);
1282
1283 /* we don't log here as rc can be overriden */
1284 rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
1285 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1286 rc = 0;
1287
1288 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1289 smk_ad_setfield_u_tsk(&ad, tsk);
1290 smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
1291 return rc;
1292}
1293
1294/**
1295 * smack_file_receive - Smack file receive check
1296 * @file: the object
1297 *
1298 * Returns 0 if current has access, error code otherwise
1299 */
1300static int smack_file_receive(struct file *file)
1301{
1302 int may = 0;
1303 struct smk_audit_info ad;
1304
1305 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1306 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1307 /*
1308 * This code relies on bitmasks.
1309 */
1310 if (file->f_mode & FMODE_READ)
1311 may = MAY_READ;
1312 if (file->f_mode & FMODE_WRITE)
1313 may |= MAY_WRITE;
1314
1315 return smk_curacc(file->f_security, may, &ad);
1316}
1317
1318/*
1319 * Task hooks
1320 */
1321
1322/**
1323 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1324 * @new: the new credentials
1325 * @gfp: the atomicity of any memory allocations
1326 *
1327 * Prepare a blank set of credentials for modification. This must allocate all
1328 * the memory the LSM module might require such that cred_transfer() can
1329 * complete without error.
1330 */
1331static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1332{
1333 struct task_smack *tsp;
1334
1335 tsp = new_task_smack(NULL, NULL, gfp);
1336 if (tsp == NULL)
1337 return -ENOMEM;
1338
1339 cred->security = tsp;
1340
1341 return 0;
1342}
1343
1344
1345/**
1346 * smack_cred_free - "free" task-level security credentials
1347 * @cred: the credentials in question
1348 *
1349 */
1350static void smack_cred_free(struct cred *cred)
1351{
1352 struct task_smack *tsp = cred->security;
1353 struct smack_rule *rp;
1354 struct list_head *l;
1355 struct list_head *n;
1356
1357 if (tsp == NULL)
1358 return;
1359 cred->security = NULL;
1360
1361 list_for_each_safe(l, n, &tsp->smk_rules) {
1362 rp = list_entry(l, struct smack_rule, list);
1363 list_del(&rp->list);
1364 kfree(rp);
1365 }
1366 kfree(tsp);
1367}
1368
1369/**
1370 * smack_cred_prepare - prepare new set of credentials for modification
1371 * @new: the new credentials
1372 * @old: the original credentials
1373 * @gfp: the atomicity of any memory allocations
1374 *
1375 * Prepare a new set of credentials for modification.
1376 */
1377static int smack_cred_prepare(struct cred *new, const struct cred *old,
1378 gfp_t gfp)
1379{
1380 struct task_smack *old_tsp = old->security;
1381 struct task_smack *new_tsp;
1382 int rc;
1383
1384 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1385 if (new_tsp == NULL)
1386 return -ENOMEM;
1387
1388 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
1389 if (rc != 0)
1390 return rc;
1391
1392 new->security = new_tsp;
1393 return 0;
1394}
1395
1396/**
1397 * smack_cred_transfer - Transfer the old credentials to the new credentials
1398 * @new: the new credentials
1399 * @old: the original credentials
1400 *
1401 * Fill in a set of blank credentials from another set of credentials.
1402 */
1403static void smack_cred_transfer(struct cred *new, const struct cred *old)
1404{
1405 struct task_smack *old_tsp = old->security;
1406 struct task_smack *new_tsp = new->security;
1407
1408 new_tsp->smk_task = old_tsp->smk_task;
1409 new_tsp->smk_forked = old_tsp->smk_task;
1410 mutex_init(&new_tsp->smk_rules_lock);
1411 INIT_LIST_HEAD(&new_tsp->smk_rules);
1412
1413
1414 /* cbs copy rule list */
1415}
1416
1417/**
1418 * smack_kernel_act_as - Set the subjective context in a set of credentials
1419 * @new: points to the set of credentials to be modified.
1420 * @secid: specifies the security ID to be set
1421 *
1422 * Set the security data for a kernel service.
1423 */
1424static int smack_kernel_act_as(struct cred *new, u32 secid)
1425{
1426 struct task_smack *new_tsp = new->security;
1427 char *smack = smack_from_secid(secid);
1428
1429 if (smack == NULL)
1430 return -EINVAL;
1431
1432 new_tsp->smk_task = smack;
1433 return 0;
1434}
1435
1436/**
1437 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1438 * @new: points to the set of credentials to be modified
1439 * @inode: points to the inode to use as a reference
1440 *
1441 * Set the file creation context in a set of credentials to the same
1442 * as the objective context of the specified inode
1443 */
1444static int smack_kernel_create_files_as(struct cred *new,
1445 struct inode *inode)
1446{
1447 struct inode_smack *isp = inode->i_security;
1448 struct task_smack *tsp = new->security;
1449
1450 tsp->smk_forked = isp->smk_inode;
1451 tsp->smk_task = isp->smk_inode;
1452 return 0;
1453}
1454
1455/**
1456 * smk_curacc_on_task - helper to log task related access
1457 * @p: the task object
1458 * @access : the access requested
1459 *
1460 * Return 0 if access is permitted
1461 */
1462static int smk_curacc_on_task(struct task_struct *p, int access)
1463{
1464 struct smk_audit_info ad;
1465
1466 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1467 smk_ad_setfield_u_tsk(&ad, p);
1468 return smk_curacc(smk_of_task(task_security(p)), access, &ad);
1469}
1470
1471/**
1472 * smack_task_setpgid - Smack check on setting pgid
1473 * @p: the task object
1474 * @pgid: unused
1475 *
1476 * Return 0 if write access is permitted
1477 */
1478static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1479{
1480 return smk_curacc_on_task(p, MAY_WRITE);
1481}
1482
1483/**
1484 * smack_task_getpgid - Smack access check for getpgid
1485 * @p: the object task
1486 *
1487 * Returns 0 if current can read the object task, error code otherwise
1488 */
1489static int smack_task_getpgid(struct task_struct *p)
1490{
1491 return smk_curacc_on_task(p, MAY_READ);
1492}
1493
1494/**
1495 * smack_task_getsid - Smack access check for getsid
1496 * @p: the object task
1497 *
1498 * Returns 0 if current can read the object task, error code otherwise
1499 */
1500static int smack_task_getsid(struct task_struct *p)
1501{
1502 return smk_curacc_on_task(p, MAY_READ);
1503}
1504
1505/**
1506 * smack_task_getsecid - get the secid of the task
1507 * @p: the object task
1508 * @secid: where to put the result
1509 *
1510 * Sets the secid to contain a u32 version of the smack label.
1511 */
1512static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1513{
1514 *secid = smack_to_secid(smk_of_task(task_security(p)));
1515}
1516
1517/**
1518 * smack_task_setnice - Smack check on setting nice
1519 * @p: the task object
1520 * @nice: unused
1521 *
1522 * Return 0 if write access is permitted
1523 */
1524static int smack_task_setnice(struct task_struct *p, int nice)
1525{
1526 int rc;
1527
1528 rc = cap_task_setnice(p, nice);
1529 if (rc == 0)
1530 rc = smk_curacc_on_task(p, MAY_WRITE);
1531 return rc;
1532}
1533
1534/**
1535 * smack_task_setioprio - Smack check on setting ioprio
1536 * @p: the task object
1537 * @ioprio: unused
1538 *
1539 * Return 0 if write access is permitted
1540 */
1541static int smack_task_setioprio(struct task_struct *p, int ioprio)
1542{
1543 int rc;
1544
1545 rc = cap_task_setioprio(p, ioprio);
1546 if (rc == 0)
1547 rc = smk_curacc_on_task(p, MAY_WRITE);
1548 return rc;
1549}
1550
1551/**
1552 * smack_task_getioprio - Smack check on reading ioprio
1553 * @p: the task object
1554 *
1555 * Return 0 if read access is permitted
1556 */
1557static int smack_task_getioprio(struct task_struct *p)
1558{
1559 return smk_curacc_on_task(p, MAY_READ);
1560}
1561
1562/**
1563 * smack_task_setscheduler - Smack check on setting scheduler
1564 * @p: the task object
1565 * @policy: unused
1566 * @lp: unused
1567 *
1568 * Return 0 if read access is permitted
1569 */
1570static int smack_task_setscheduler(struct task_struct *p)
1571{
1572 int rc;
1573
1574 rc = cap_task_setscheduler(p);
1575 if (rc == 0)
1576 rc = smk_curacc_on_task(p, MAY_WRITE);
1577 return rc;
1578}
1579
1580/**
1581 * smack_task_getscheduler - Smack check on reading scheduler
1582 * @p: the task object
1583 *
1584 * Return 0 if read access is permitted
1585 */
1586static int smack_task_getscheduler(struct task_struct *p)
1587{
1588 return smk_curacc_on_task(p, MAY_READ);
1589}
1590
1591/**
1592 * smack_task_movememory - Smack check on moving memory
1593 * @p: the task object
1594 *
1595 * Return 0 if write access is permitted
1596 */
1597static int smack_task_movememory(struct task_struct *p)
1598{
1599 return smk_curacc_on_task(p, MAY_WRITE);
1600}
1601
1602/**
1603 * smack_task_kill - Smack check on signal delivery
1604 * @p: the task object
1605 * @info: unused
1606 * @sig: unused
1607 * @secid: identifies the smack to use in lieu of current's
1608 *
1609 * Return 0 if write access is permitted
1610 *
1611 * The secid behavior is an artifact of an SELinux hack
1612 * in the USB code. Someday it may go away.
1613 */
1614static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1615 int sig, u32 secid)
1616{
1617 struct smk_audit_info ad;
1618
1619 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1620 smk_ad_setfield_u_tsk(&ad, p);
1621 /*
1622 * Sending a signal requires that the sender
1623 * can write the receiver.
1624 */
1625 if (secid == 0)
1626 return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE,
1627 &ad);
1628 /*
1629 * If the secid isn't 0 we're dealing with some USB IO
1630 * specific behavior. This is not clean. For one thing
1631 * we can't take privilege into account.
1632 */
1633 return smk_access(smack_from_secid(secid),
1634 smk_of_task(task_security(p)), MAY_WRITE, &ad);
1635}
1636
1637/**
1638 * smack_task_wait - Smack access check for waiting
1639 * @p: task to wait for
1640 *
1641 * Returns 0 if current can wait for p, error code otherwise
1642 */
1643static int smack_task_wait(struct task_struct *p)
1644{
1645 struct smk_audit_info ad;
1646 char *sp = smk_of_current();
1647 char *tsp = smk_of_forked(task_security(p));
1648 int rc;
1649
1650 /* we don't log here, we can be overriden */
1651 rc = smk_access(tsp, sp, MAY_WRITE, NULL);
1652 if (rc == 0)
1653 goto out_log;
1654
1655 /*
1656 * Allow the operation to succeed if either task
1657 * has privilege to perform operations that might
1658 * account for the smack labels having gotten to
1659 * be different in the first place.
1660 *
1661 * This breaks the strict subject/object access
1662 * control ideal, taking the object's privilege
1663 * state into account in the decision as well as
1664 * the smack value.
1665 */
1666 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
1667 rc = 0;
1668 /* we log only if we didn't get overriden */
1669 out_log:
1670 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1671 smk_ad_setfield_u_tsk(&ad, p);
1672 smack_log(tsp, sp, MAY_WRITE, rc, &ad);
1673 return rc;
1674}
1675
1676/**
1677 * smack_task_to_inode - copy task smack into the inode blob
1678 * @p: task to copy from
1679 * @inode: inode to copy to
1680 *
1681 * Sets the smack pointer in the inode security blob
1682 */
1683static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1684{
1685 struct inode_smack *isp = inode->i_security;
1686 isp->smk_inode = smk_of_task(task_security(p));
1687}
1688
1689/*
1690 * Socket hooks.
1691 */
1692
1693/**
1694 * smack_sk_alloc_security - Allocate a socket blob
1695 * @sk: the socket
1696 * @family: unused
1697 * @gfp_flags: memory allocation flags
1698 *
1699 * Assign Smack pointers to current
1700 *
1701 * Returns 0 on success, -ENOMEM is there's no memory
1702 */
1703static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1704{
1705 char *csp = smk_of_current();
1706 struct socket_smack *ssp;
1707
1708 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1709 if (ssp == NULL)
1710 return -ENOMEM;
1711
1712 ssp->smk_in = csp;
1713 ssp->smk_out = csp;
1714 ssp->smk_packet[0] = '\0';
1715
1716 sk->sk_security = ssp;
1717
1718 return 0;
1719}
1720
1721/**
1722 * smack_sk_free_security - Free a socket blob
1723 * @sk: the socket
1724 *
1725 * Clears the blob pointer
1726 */
1727static void smack_sk_free_security(struct sock *sk)
1728{
1729 kfree(sk->sk_security);
1730}
1731
1732/**
1733* smack_host_label - check host based restrictions
1734* @sip: the object end
1735*
1736* looks for host based access restrictions
1737*
1738* This version will only be appropriate for really small sets of single label
1739* hosts. The caller is responsible for ensuring that the RCU read lock is
1740* taken before calling this function.
1741*
1742* Returns the label of the far end or NULL if it's not special.
1743*/
1744static char *smack_host_label(struct sockaddr_in *sip)
1745{
1746 struct smk_netlbladdr *snp;
1747 struct in_addr *siap = &sip->sin_addr;
1748
1749 if (siap->s_addr == 0)
1750 return NULL;
1751
1752 list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list)
1753 /*
1754 * we break after finding the first match because
1755 * the list is sorted from longest to shortest mask
1756 * so we have found the most specific match
1757 */
1758 if ((&snp->smk_host.sin_addr)->s_addr ==
1759 (siap->s_addr & (&snp->smk_mask)->s_addr)) {
1760 /* we have found the special CIPSO option */
1761 if (snp->smk_label == smack_cipso_option)
1762 return NULL;
1763 return snp->smk_label;
1764 }
1765
1766 return NULL;
1767}
1768
1769/**
1770 * smack_set_catset - convert a capset to netlabel mls categories
1771 * @catset: the Smack categories
1772 * @sap: where to put the netlabel categories
1773 *
1774 * Allocates and fills attr.mls.cat
1775 */
1776static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1777{
1778 unsigned char *cp;
1779 unsigned char m;
1780 int cat;
1781 int rc;
1782 int byte;
1783
1784 if (!catset)
1785 return;
1786
1787 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1788 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1789 sap->attr.mls.cat->startbit = 0;
1790
1791 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1792 for (m = 0x80; m != 0; m >>= 1, cat++) {
1793 if ((m & *cp) == 0)
1794 continue;
1795 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1796 cat, GFP_ATOMIC);
1797 }
1798}
1799
1800/**
1801 * smack_to_secattr - fill a secattr from a smack value
1802 * @smack: the smack value
1803 * @nlsp: where the result goes
1804 *
1805 * Casey says that CIPSO is good enough for now.
1806 * It can be used to effect.
1807 * It can also be abused to effect when necessary.
1808 * Apologies to the TSIG group in general and GW in particular.
1809 */
1810static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1811{
1812 struct smack_cipso cipso;
1813 int rc;
1814
1815 nlsp->domain = smack;
1816 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1817
1818 rc = smack_to_cipso(smack, &cipso);
1819 if (rc == 0) {
1820 nlsp->attr.mls.lvl = cipso.smk_level;
1821 smack_set_catset(cipso.smk_catset, nlsp);
1822 } else {
1823 nlsp->attr.mls.lvl = smack_cipso_direct;
1824 smack_set_catset(smack, nlsp);
1825 }
1826}
1827
1828/**
1829 * smack_netlabel - Set the secattr on a socket
1830 * @sk: the socket
1831 * @labeled: socket label scheme
1832 *
1833 * Convert the outbound smack value (smk_out) to a
1834 * secattr and attach it to the socket.
1835 *
1836 * Returns 0 on success or an error code
1837 */
1838static int smack_netlabel(struct sock *sk, int labeled)
1839{
1840 struct socket_smack *ssp = sk->sk_security;
1841 struct netlbl_lsm_secattr secattr;
1842 int rc = 0;
1843
1844 /*
1845 * Usually the netlabel code will handle changing the
1846 * packet labeling based on the label.
1847 * The case of a single label host is different, because
1848 * a single label host should never get a labeled packet
1849 * even though the label is usually associated with a packet
1850 * label.
1851 */
1852 local_bh_disable();
1853 bh_lock_sock_nested(sk);
1854
1855 if (ssp->smk_out == smack_net_ambient ||
1856 labeled == SMACK_UNLABELED_SOCKET)
1857 netlbl_sock_delattr(sk);
1858 else {
1859 netlbl_secattr_init(&secattr);
1860 smack_to_secattr(ssp->smk_out, &secattr);
1861 rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
1862 netlbl_secattr_destroy(&secattr);
1863 }
1864
1865 bh_unlock_sock(sk);
1866 local_bh_enable();
1867
1868 return rc;
1869}
1870
1871/**
1872 * smack_netlbel_send - Set the secattr on a socket and perform access checks
1873 * @sk: the socket
1874 * @sap: the destination address
1875 *
1876 * Set the correct secattr for the given socket based on the destination
1877 * address and perform any outbound access checks needed.
1878 *
1879 * Returns 0 on success or an error code.
1880 *
1881 */
1882static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
1883{
1884 int rc;
1885 int sk_lbl;
1886 char *hostsp;
1887 struct socket_smack *ssp = sk->sk_security;
1888 struct smk_audit_info ad;
1889
1890 rcu_read_lock();
1891 hostsp = smack_host_label(sap);
1892 if (hostsp != NULL) {
1893 sk_lbl = SMACK_UNLABELED_SOCKET;
1894#ifdef CONFIG_AUDIT
1895 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
1896 ad.a.u.net.family = sap->sin_family;
1897 ad.a.u.net.dport = sap->sin_port;
1898 ad.a.u.net.v4info.daddr = sap->sin_addr.s_addr;
1899#endif
1900 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
1901 } else {
1902 sk_lbl = SMACK_CIPSO_SOCKET;
1903 rc = 0;
1904 }
1905 rcu_read_unlock();
1906 if (rc != 0)
1907 return rc;
1908
1909 return smack_netlabel(sk, sk_lbl);
1910}
1911
1912/**
1913 * smack_inode_setsecurity - set smack xattrs
1914 * @inode: the object
1915 * @name: attribute name
1916 * @value: attribute value
1917 * @size: size of the attribute
1918 * @flags: unused
1919 *
1920 * Sets the named attribute in the appropriate blob
1921 *
1922 * Returns 0 on success, or an error code
1923 */
1924static int smack_inode_setsecurity(struct inode *inode, const char *name,
1925 const void *value, size_t size, int flags)
1926{
1927 char *sp;
1928 struct inode_smack *nsp = inode->i_security;
1929 struct socket_smack *ssp;
1930 struct socket *sock;
1931 int rc = 0;
1932
1933 if (value == NULL || size > SMK_LABELLEN || size == 0)
1934 return -EACCES;
1935
1936 sp = smk_import(value, size);
1937 if (sp == NULL)
1938 return -EINVAL;
1939
1940 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1941 nsp->smk_inode = sp;
1942 nsp->smk_flags |= SMK_INODE_INSTANT;
1943 return 0;
1944 }
1945 /*
1946 * The rest of the Smack xattrs are only on sockets.
1947 */
1948 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1949 return -EOPNOTSUPP;
1950
1951 sock = SOCKET_I(inode);
1952 if (sock == NULL || sock->sk == NULL)
1953 return -EOPNOTSUPP;
1954
1955 ssp = sock->sk->sk_security;
1956
1957 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1958 ssp->smk_in = sp;
1959 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1960 ssp->smk_out = sp;
1961 if (sock->sk->sk_family != PF_UNIX) {
1962 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
1963 if (rc != 0)
1964 printk(KERN_WARNING
1965 "Smack: \"%s\" netlbl error %d.\n",
1966 __func__, -rc);
1967 }
1968 } else
1969 return -EOPNOTSUPP;
1970
1971 return 0;
1972}
1973
1974/**
1975 * smack_socket_post_create - finish socket setup
1976 * @sock: the socket
1977 * @family: protocol family
1978 * @type: unused
1979 * @protocol: unused
1980 * @kern: unused
1981 *
1982 * Sets the netlabel information on the socket
1983 *
1984 * Returns 0 on success, and error code otherwise
1985 */
1986static int smack_socket_post_create(struct socket *sock, int family,
1987 int type, int protocol, int kern)
1988{
1989 if (family != PF_INET || sock->sk == NULL)
1990 return 0;
1991 /*
1992 * Set the outbound netlbl.
1993 */
1994 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
1995}
1996
1997/**
1998 * smack_socket_connect - connect access check
1999 * @sock: the socket
2000 * @sap: the other end
2001 * @addrlen: size of sap
2002 *
2003 * Verifies that a connection may be possible
2004 *
2005 * Returns 0 on success, and error code otherwise
2006 */
2007static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2008 int addrlen)
2009{
2010 if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
2011 return 0;
2012 if (addrlen < sizeof(struct sockaddr_in))
2013 return -EINVAL;
2014
2015 return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2016}
2017
2018/**
2019 * smack_flags_to_may - convert S_ to MAY_ values
2020 * @flags: the S_ value
2021 *
2022 * Returns the equivalent MAY_ value
2023 */
2024static int smack_flags_to_may(int flags)
2025{
2026 int may = 0;
2027
2028 if (flags & S_IRUGO)
2029 may |= MAY_READ;
2030 if (flags & S_IWUGO)
2031 may |= MAY_WRITE;
2032 if (flags & S_IXUGO)
2033 may |= MAY_EXEC;
2034
2035 return may;
2036}
2037
2038/**
2039 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2040 * @msg: the object
2041 *
2042 * Returns 0
2043 */
2044static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2045{
2046 msg->security = smk_of_current();
2047 return 0;
2048}
2049
2050/**
2051 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2052 * @msg: the object
2053 *
2054 * Clears the blob pointer
2055 */
2056static void smack_msg_msg_free_security(struct msg_msg *msg)
2057{
2058 msg->security = NULL;
2059}
2060
2061/**
2062 * smack_of_shm - the smack pointer for the shm
2063 * @shp: the object
2064 *
2065 * Returns a pointer to the smack value
2066 */
2067static char *smack_of_shm(struct shmid_kernel *shp)
2068{
2069 return (char *)shp->shm_perm.security;
2070}
2071
2072/**
2073 * smack_shm_alloc_security - Set the security blob for shm
2074 * @shp: the object
2075 *
2076 * Returns 0
2077 */
2078static int smack_shm_alloc_security(struct shmid_kernel *shp)
2079{
2080 struct kern_ipc_perm *isp = &shp->shm_perm;
2081
2082 isp->security = smk_of_current();
2083 return 0;
2084}
2085
2086/**
2087 * smack_shm_free_security - Clear the security blob for shm
2088 * @shp: the object
2089 *
2090 * Clears the blob pointer
2091 */
2092static void smack_shm_free_security(struct shmid_kernel *shp)
2093{
2094 struct kern_ipc_perm *isp = &shp->shm_perm;
2095
2096 isp->security = NULL;
2097}
2098
2099/**
2100 * smk_curacc_shm : check if current has access on shm
2101 * @shp : the object
2102 * @access : access requested
2103 *
2104 * Returns 0 if current has the requested access, error code otherwise
2105 */
2106static int smk_curacc_shm(struct shmid_kernel *shp, int access)
2107{
2108 char *ssp = smack_of_shm(shp);
2109 struct smk_audit_info ad;
2110
2111#ifdef CONFIG_AUDIT
2112 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2113 ad.a.u.ipc_id = shp->shm_perm.id;
2114#endif
2115 return smk_curacc(ssp, access, &ad);
2116}
2117
2118/**
2119 * smack_shm_associate - Smack access check for shm
2120 * @shp: the object
2121 * @shmflg: access requested
2122 *
2123 * Returns 0 if current has the requested access, error code otherwise
2124 */
2125static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
2126{
2127 int may;
2128
2129 may = smack_flags_to_may(shmflg);
2130 return smk_curacc_shm(shp, may);
2131}
2132
2133/**
2134 * smack_shm_shmctl - Smack access check for shm
2135 * @shp: the object
2136 * @cmd: what it wants to do
2137 *
2138 * Returns 0 if current has the requested access, error code otherwise
2139 */
2140static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
2141{
2142 int may;
2143
2144 switch (cmd) {
2145 case IPC_STAT:
2146 case SHM_STAT:
2147 may = MAY_READ;
2148 break;
2149 case IPC_SET:
2150 case SHM_LOCK:
2151 case SHM_UNLOCK:
2152 case IPC_RMID:
2153 may = MAY_READWRITE;
2154 break;
2155 case IPC_INFO:
2156 case SHM_INFO:
2157 /*
2158 * System level information.
2159 */
2160 return 0;
2161 default:
2162 return -EINVAL;
2163 }
2164 return smk_curacc_shm(shp, may);
2165}
2166
2167/**
2168 * smack_shm_shmat - Smack access for shmat
2169 * @shp: the object
2170 * @shmaddr: unused
2171 * @shmflg: access requested
2172 *
2173 * Returns 0 if current has the requested access, error code otherwise
2174 */
2175static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
2176 int shmflg)
2177{
2178 int may;
2179
2180 may = smack_flags_to_may(shmflg);
2181 return smk_curacc_shm(shp, may);
2182}
2183
2184/**
2185 * smack_of_sem - the smack pointer for the sem
2186 * @sma: the object
2187 *
2188 * Returns a pointer to the smack value
2189 */
2190static char *smack_of_sem(struct sem_array *sma)
2191{
2192 return (char *)sma->sem_perm.security;
2193}
2194
2195/**
2196 * smack_sem_alloc_security - Set the security blob for sem
2197 * @sma: the object
2198 *
2199 * Returns 0
2200 */
2201static int smack_sem_alloc_security(struct sem_array *sma)
2202{
2203 struct kern_ipc_perm *isp = &sma->sem_perm;
2204
2205 isp->security = smk_of_current();
2206 return 0;
2207}
2208
2209/**
2210 * smack_sem_free_security - Clear the security blob for sem
2211 * @sma: the object
2212 *
2213 * Clears the blob pointer
2214 */
2215static void smack_sem_free_security(struct sem_array *sma)
2216{
2217 struct kern_ipc_perm *isp = &sma->sem_perm;
2218
2219 isp->security = NULL;
2220}
2221
2222/**
2223 * smk_curacc_sem : check if current has access on sem
2224 * @sma : the object
2225 * @access : access requested
2226 *
2227 * Returns 0 if current has the requested access, error code otherwise
2228 */
2229static int smk_curacc_sem(struct sem_array *sma, int access)
2230{
2231 char *ssp = smack_of_sem(sma);
2232 struct smk_audit_info ad;
2233
2234#ifdef CONFIG_AUDIT
2235 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2236 ad.a.u.ipc_id = sma->sem_perm.id;
2237#endif
2238 return smk_curacc(ssp, access, &ad);
2239}
2240
2241/**
2242 * smack_sem_associate - Smack access check for sem
2243 * @sma: the object
2244 * @semflg: access requested
2245 *
2246 * Returns 0 if current has the requested access, error code otherwise
2247 */
2248static int smack_sem_associate(struct sem_array *sma, int semflg)
2249{
2250 int may;
2251
2252 may = smack_flags_to_may(semflg);
2253 return smk_curacc_sem(sma, may);
2254}
2255
2256/**
2257 * smack_sem_shmctl - Smack access check for sem
2258 * @sma: the object
2259 * @cmd: what it wants to do
2260 *
2261 * Returns 0 if current has the requested access, error code otherwise
2262 */
2263static int smack_sem_semctl(struct sem_array *sma, int cmd)
2264{
2265 int may;
2266
2267 switch (cmd) {
2268 case GETPID:
2269 case GETNCNT:
2270 case GETZCNT:
2271 case GETVAL:
2272 case GETALL:
2273 case IPC_STAT:
2274 case SEM_STAT:
2275 may = MAY_READ;
2276 break;
2277 case SETVAL:
2278 case SETALL:
2279 case IPC_RMID:
2280 case IPC_SET:
2281 may = MAY_READWRITE;
2282 break;
2283 case IPC_INFO:
2284 case SEM_INFO:
2285 /*
2286 * System level information
2287 */
2288 return 0;
2289 default:
2290 return -EINVAL;
2291 }
2292
2293 return smk_curacc_sem(sma, may);
2294}
2295
2296/**
2297 * smack_sem_semop - Smack checks of semaphore operations
2298 * @sma: the object
2299 * @sops: unused
2300 * @nsops: unused
2301 * @alter: unused
2302 *
2303 * Treated as read and write in all cases.
2304 *
2305 * Returns 0 if access is allowed, error code otherwise
2306 */
2307static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
2308 unsigned nsops, int alter)
2309{
2310 return smk_curacc_sem(sma, MAY_READWRITE);
2311}
2312
2313/**
2314 * smack_msg_alloc_security - Set the security blob for msg
2315 * @msq: the object
2316 *
2317 * Returns 0
2318 */
2319static int smack_msg_queue_alloc_security(struct msg_queue *msq)
2320{
2321 struct kern_ipc_perm *kisp = &msq->q_perm;
2322
2323 kisp->security = smk_of_current();
2324 return 0;
2325}
2326
2327/**
2328 * smack_msg_free_security - Clear the security blob for msg
2329 * @msq: the object
2330 *
2331 * Clears the blob pointer
2332 */
2333static void smack_msg_queue_free_security(struct msg_queue *msq)
2334{
2335 struct kern_ipc_perm *kisp = &msq->q_perm;
2336
2337 kisp->security = NULL;
2338}
2339
2340/**
2341 * smack_of_msq - the smack pointer for the msq
2342 * @msq: the object
2343 *
2344 * Returns a pointer to the smack value
2345 */
2346static char *smack_of_msq(struct msg_queue *msq)
2347{
2348 return (char *)msq->q_perm.security;
2349}
2350
2351/**
2352 * smk_curacc_msq : helper to check if current has access on msq
2353 * @msq : the msq
2354 * @access : access requested
2355 *
2356 * return 0 if current has access, error otherwise
2357 */
2358static int smk_curacc_msq(struct msg_queue *msq, int access)
2359{
2360 char *msp = smack_of_msq(msq);
2361 struct smk_audit_info ad;
2362
2363#ifdef CONFIG_AUDIT
2364 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2365 ad.a.u.ipc_id = msq->q_perm.id;
2366#endif
2367 return smk_curacc(msp, access, &ad);
2368}
2369
2370/**
2371 * smack_msg_queue_associate - Smack access check for msg_queue
2372 * @msq: the object
2373 * @msqflg: access requested
2374 *
2375 * Returns 0 if current has the requested access, error code otherwise
2376 */
2377static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
2378{
2379 int may;
2380
2381 may = smack_flags_to_may(msqflg);
2382 return smk_curacc_msq(msq, may);
2383}
2384
2385/**
2386 * smack_msg_queue_msgctl - Smack access check for msg_queue
2387 * @msq: the object
2388 * @cmd: what it wants to do
2389 *
2390 * Returns 0 if current has the requested access, error code otherwise
2391 */
2392static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
2393{
2394 int may;
2395
2396 switch (cmd) {
2397 case IPC_STAT:
2398 case MSG_STAT:
2399 may = MAY_READ;
2400 break;
2401 case IPC_SET:
2402 case IPC_RMID:
2403 may = MAY_READWRITE;
2404 break;
2405 case IPC_INFO:
2406 case MSG_INFO:
2407 /*
2408 * System level information
2409 */
2410 return 0;
2411 default:
2412 return -EINVAL;
2413 }
2414
2415 return smk_curacc_msq(msq, may);
2416}
2417
2418/**
2419 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2420 * @msq: the object
2421 * @msg: unused
2422 * @msqflg: access requested
2423 *
2424 * Returns 0 if current has the requested access, error code otherwise
2425 */
2426static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
2427 int msqflg)
2428{
2429 int may;
2430
2431 may = smack_flags_to_may(msqflg);
2432 return smk_curacc_msq(msq, may);
2433}
2434
2435/**
2436 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2437 * @msq: the object
2438 * @msg: unused
2439 * @target: unused
2440 * @type: unused
2441 * @mode: unused
2442 *
2443 * Returns 0 if current has read and write access, error code otherwise
2444 */
2445static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
2446 struct task_struct *target, long type, int mode)
2447{
2448 return smk_curacc_msq(msq, MAY_READWRITE);
2449}
2450
2451/**
2452 * smack_ipc_permission - Smack access for ipc_permission()
2453 * @ipp: the object permissions
2454 * @flag: access requested
2455 *
2456 * Returns 0 if current has read and write access, error code otherwise
2457 */
2458static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
2459{
2460 char *isp = ipp->security;
2461 int may = smack_flags_to_may(flag);
2462 struct smk_audit_info ad;
2463
2464#ifdef CONFIG_AUDIT
2465 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2466 ad.a.u.ipc_id = ipp->id;
2467#endif
2468 return smk_curacc(isp, may, &ad);
2469}
2470
2471/**
2472 * smack_ipc_getsecid - Extract smack security id
2473 * @ipp: the object permissions
2474 * @secid: where result will be saved
2475 */
2476static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
2477{
2478 char *smack = ipp->security;
2479
2480 *secid = smack_to_secid(smack);
2481}
2482
2483/**
2484 * smack_d_instantiate - Make sure the blob is correct on an inode
2485 * @opt_dentry: dentry where inode will be attached
2486 * @inode: the object
2487 *
2488 * Set the inode's security blob if it hasn't been done already.
2489 */
2490static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
2491{
2492 struct super_block *sbp;
2493 struct superblock_smack *sbsp;
2494 struct inode_smack *isp;
2495 char *csp = smk_of_current();
2496 char *fetched;
2497 char *final;
2498 char trattr[TRANS_TRUE_SIZE];
2499 int transflag = 0;
2500 struct dentry *dp;
2501
2502 if (inode == NULL)
2503 return;
2504
2505 isp = inode->i_security;
2506
2507 mutex_lock(&isp->smk_lock);
2508 /*
2509 * If the inode is already instantiated
2510 * take the quick way out
2511 */
2512 if (isp->smk_flags & SMK_INODE_INSTANT)
2513 goto unlockandout;
2514
2515 sbp = inode->i_sb;
2516 sbsp = sbp->s_security;
2517 /*
2518 * We're going to use the superblock default label
2519 * if there's no label on the file.
2520 */
2521 final = sbsp->smk_default;
2522
2523 /*
2524 * If this is the root inode the superblock
2525 * may be in the process of initialization.
2526 * If that is the case use the root value out
2527 * of the superblock.
2528 */
2529 if (opt_dentry->d_parent == opt_dentry) {
2530 isp->smk_inode = sbsp->smk_root;
2531 isp->smk_flags |= SMK_INODE_INSTANT;
2532 goto unlockandout;
2533 }
2534
2535 /*
2536 * This is pretty hackish.
2537 * Casey says that we shouldn't have to do
2538 * file system specific code, but it does help
2539 * with keeping it simple.
2540 */
2541 switch (sbp->s_magic) {
2542 case SMACK_MAGIC:
2543 /*
2544 * Casey says that it's a little embarrassing
2545 * that the smack file system doesn't do
2546 * extended attributes.
2547 */
2548 final = smack_known_star.smk_known;
2549 break;
2550 case PIPEFS_MAGIC:
2551 /*
2552 * Casey says pipes are easy (?)
2553 */
2554 final = smack_known_star.smk_known;
2555 break;
2556 case DEVPTS_SUPER_MAGIC:
2557 /*
2558 * devpts seems content with the label of the task.
2559 * Programs that change smack have to treat the
2560 * pty with respect.
2561 */
2562 final = csp;
2563 break;
2564 case SOCKFS_MAGIC:
2565 /*
2566 * Socket access is controlled by the socket
2567 * structures associated with the task involved.
2568 */
2569 final = smack_known_star.smk_known;
2570 break;
2571 case PROC_SUPER_MAGIC:
2572 /*
2573 * Casey says procfs appears not to care.
2574 * The superblock default suffices.
2575 */
2576 break;
2577 case TMPFS_MAGIC:
2578 /*
2579 * Device labels should come from the filesystem,
2580 * but watch out, because they're volitile,
2581 * getting recreated on every reboot.
2582 */
2583 final = smack_known_star.smk_known;
2584 /*
2585 * No break.
2586 *
2587 * If a smack value has been set we want to use it,
2588 * but since tmpfs isn't giving us the opportunity
2589 * to set mount options simulate setting the
2590 * superblock default.
2591 */
2592 default:
2593 /*
2594 * This isn't an understood special case.
2595 * Get the value from the xattr.
2596 */
2597
2598 /*
2599 * UNIX domain sockets use lower level socket data.
2600 */
2601 if (S_ISSOCK(inode->i_mode)) {
2602 final = smack_known_star.smk_known;
2603 break;
2604 }
2605 /*
2606 * No xattr support means, alas, no SMACK label.
2607 * Use the aforeapplied default.
2608 * It would be curious if the label of the task
2609 * does not match that assigned.
2610 */
2611 if (inode->i_op->getxattr == NULL)
2612 break;
2613 /*
2614 * Get the dentry for xattr.
2615 */
2616 dp = dget(opt_dentry);
2617 fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
2618 if (fetched != NULL) {
2619 final = fetched;
2620 if (S_ISDIR(inode->i_mode)) {
2621 trattr[0] = '\0';
2622 inode->i_op->getxattr(dp,
2623 XATTR_NAME_SMACKTRANSMUTE,
2624 trattr, TRANS_TRUE_SIZE);
2625 if (strncmp(trattr, TRANS_TRUE,
2626 TRANS_TRUE_SIZE) == 0)
2627 transflag = SMK_INODE_TRANSMUTE;
2628 }
2629 }
2630 isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
2631 isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
2632
2633 dput(dp);
2634 break;
2635 }
2636
2637 if (final == NULL)
2638 isp->smk_inode = csp;
2639 else
2640 isp->smk_inode = final;
2641
2642 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
2643
2644unlockandout:
2645 mutex_unlock(&isp->smk_lock);
2646 return;
2647}
2648
2649/**
2650 * smack_getprocattr - Smack process attribute access
2651 * @p: the object task
2652 * @name: the name of the attribute in /proc/.../attr
2653 * @value: where to put the result
2654 *
2655 * Places a copy of the task Smack into value
2656 *
2657 * Returns the length of the smack label or an error code
2658 */
2659static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2660{
2661 char *cp;
2662 int slen;
2663
2664 if (strcmp(name, "current") != 0)
2665 return -EINVAL;
2666
2667 cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL);
2668 if (cp == NULL)
2669 return -ENOMEM;
2670
2671 slen = strlen(cp);
2672 *value = cp;
2673 return slen;
2674}
2675
2676/**
2677 * smack_setprocattr - Smack process attribute setting
2678 * @p: the object task
2679 * @name: the name of the attribute in /proc/.../attr
2680 * @value: the value to set
2681 * @size: the size of the value
2682 *
2683 * Sets the Smack value of the task. Only setting self
2684 * is permitted and only with privilege
2685 *
2686 * Returns the length of the smack label or an error code
2687 */
2688static int smack_setprocattr(struct task_struct *p, char *name,
2689 void *value, size_t size)
2690{
2691 int rc;
2692 struct task_smack *tsp;
2693 struct task_smack *oldtsp;
2694 struct cred *new;
2695 char *newsmack;
2696
2697 /*
2698 * Changing another process' Smack value is too dangerous
2699 * and supports no sane use case.
2700 */
2701 if (p != current)
2702 return -EPERM;
2703
2704 if (!capable(CAP_MAC_ADMIN))
2705 return -EPERM;
2706
2707 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2708 return -EINVAL;
2709
2710 if (strcmp(name, "current") != 0)
2711 return -EINVAL;
2712
2713 newsmack = smk_import(value, size);
2714 if (newsmack == NULL)
2715 return -EINVAL;
2716
2717 /*
2718 * No process is ever allowed the web ("@") label.
2719 */
2720 if (newsmack == smack_known_web.smk_known)
2721 return -EPERM;
2722
2723 oldtsp = p->cred->security;
2724 new = prepare_creds();
2725 if (new == NULL)
2726 return -ENOMEM;
2727
2728 tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
2729 if (tsp == NULL) {
2730 kfree(new);
2731 return -ENOMEM;
2732 }
2733 rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
2734 if (rc != 0)
2735 return rc;
2736
2737 new->security = tsp;
2738 commit_creds(new);
2739 return size;
2740}
2741
2742/**
2743 * smack_unix_stream_connect - Smack access on UDS
2744 * @sock: one sock
2745 * @other: the other sock
2746 * @newsk: unused
2747 *
2748 * Return 0 if a subject with the smack of sock could access
2749 * an object with the smack of other, otherwise an error code
2750 */
2751static int smack_unix_stream_connect(struct sock *sock,
2752 struct sock *other, struct sock *newsk)
2753{
2754 struct socket_smack *ssp = sock->sk_security;
2755 struct socket_smack *osp = other->sk_security;
2756 struct smk_audit_info ad;
2757 int rc = 0;
2758
2759 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2760 smk_ad_setfield_u_net_sk(&ad, other);
2761
2762 if (!capable(CAP_MAC_OVERRIDE))
2763 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2764
2765 return rc;
2766}
2767
2768/**
2769 * smack_unix_may_send - Smack access on UDS
2770 * @sock: one socket
2771 * @other: the other socket
2772 *
2773 * Return 0 if a subject with the smack of sock could access
2774 * an object with the smack of other, otherwise an error code
2775 */
2776static int smack_unix_may_send(struct socket *sock, struct socket *other)
2777{
2778 struct socket_smack *ssp = sock->sk->sk_security;
2779 struct socket_smack *osp = other->sk->sk_security;
2780 struct smk_audit_info ad;
2781 int rc = 0;
2782
2783 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2784 smk_ad_setfield_u_net_sk(&ad, other->sk);
2785
2786 if (!capable(CAP_MAC_OVERRIDE))
2787 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2788
2789 return rc;
2790}
2791
2792/**
2793 * smack_socket_sendmsg - Smack check based on destination host
2794 * @sock: the socket
2795 * @msg: the message
2796 * @size: the size of the message
2797 *
2798 * Return 0 if the current subject can write to the destination
2799 * host. This is only a question if the destination is a single
2800 * label host.
2801 */
2802static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
2803 int size)
2804{
2805 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
2806
2807 /*
2808 * Perfectly reasonable for this to be NULL
2809 */
2810 if (sip == NULL || sip->sin_family != AF_INET)
2811 return 0;
2812
2813 return smack_netlabel_send(sock->sk, sip);
2814}
2815
2816
2817/**
2818 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
2819 * @sap: netlabel secattr
2820 * @sip: where to put the result
2821 *
2822 * Copies a smack label into sip
2823 */
2824static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2825{
2826 char smack[SMK_LABELLEN];
2827 char *sp;
2828 int pcat;
2829
2830 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
2831 /*
2832 * Looks like a CIPSO packet.
2833 * If there are flags but no level netlabel isn't
2834 * behaving the way we expect it to.
2835 *
2836 * Get the categories, if any
2837 * Without guidance regarding the smack value
2838 * for the packet fall back on the network
2839 * ambient value.
2840 */
2841 memset(smack, '\0', SMK_LABELLEN);
2842 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2843 for (pcat = -1;;) {
2844 pcat = netlbl_secattr_catmap_walk(
2845 sap->attr.mls.cat, pcat + 1);
2846 if (pcat < 0)
2847 break;
2848 smack_catset_bit(pcat, smack);
2849 }
2850 /*
2851 * If it is CIPSO using smack direct mapping
2852 * we are already done. WeeHee.
2853 */
2854 if (sap->attr.mls.lvl == smack_cipso_direct) {
2855 memcpy(sip, smack, SMK_MAXLEN);
2856 return;
2857 }
2858 /*
2859 * Look it up in the supplied table if it is not
2860 * a direct mapping.
2861 */
2862 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
2863 return;
2864 }
2865 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
2866 /*
2867 * Looks like a fallback, which gives us a secid.
2868 */
2869 sp = smack_from_secid(sap->attr.secid);
2870 /*
2871 * This has got to be a bug because it is
2872 * impossible to specify a fallback without
2873 * specifying the label, which will ensure
2874 * it has a secid, and the only way to get a
2875 * secid is from a fallback.
2876 */
2877 BUG_ON(sp == NULL);
2878 strncpy(sip, sp, SMK_MAXLEN);
2879 return;
2880 }
2881 /*
2882 * Without guidance regarding the smack value
2883 * for the packet fall back on the network
2884 * ambient value.
2885 */
2886 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
2887 return;
2888}
2889
2890/**
2891 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2892 * @sk: socket
2893 * @skb: packet
2894 *
2895 * Returns 0 if the packet should be delivered, an error code otherwise
2896 */
2897static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2898{
2899 struct netlbl_lsm_secattr secattr;
2900 struct socket_smack *ssp = sk->sk_security;
2901 char smack[SMK_LABELLEN];
2902 char *csp;
2903 int rc;
2904 struct smk_audit_info ad;
2905 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2906 return 0;
2907
2908 /*
2909 * Translate what netlabel gave us.
2910 */
2911 netlbl_secattr_init(&secattr);
2912
2913 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
2914 if (rc == 0) {
2915 smack_from_secattr(&secattr, smack);
2916 csp = smack;
2917 } else
2918 csp = smack_net_ambient;
2919
2920 netlbl_secattr_destroy(&secattr);
2921
2922#ifdef CONFIG_AUDIT
2923 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2924 ad.a.u.net.family = sk->sk_family;
2925 ad.a.u.net.netif = skb->skb_iif;
2926 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
2927#endif
2928 /*
2929 * Receiving a packet requires that the other end
2930 * be able to write here. Read access is not required.
2931 * This is the simplist possible security model
2932 * for networking.
2933 */
2934 rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
2935 if (rc != 0)
2936 netlbl_skbuff_err(skb, rc, 0);
2937 return rc;
2938}
2939
2940/**
2941 * smack_socket_getpeersec_stream - pull in packet label
2942 * @sock: the socket
2943 * @optval: user's destination
2944 * @optlen: size thereof
2945 * @len: max thereof
2946 *
2947 * returns zero on success, an error code otherwise
2948 */
2949static int smack_socket_getpeersec_stream(struct socket *sock,
2950 char __user *optval,
2951 int __user *optlen, unsigned len)
2952{
2953 struct socket_smack *ssp;
2954 int slen;
2955 int rc = 0;
2956
2957 ssp = sock->sk->sk_security;
2958 slen = strlen(ssp->smk_packet) + 1;
2959
2960 if (slen > len)
2961 rc = -ERANGE;
2962 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2963 rc = -EFAULT;
2964
2965 if (put_user(slen, optlen) != 0)
2966 rc = -EFAULT;
2967
2968 return rc;
2969}
2970
2971
2972/**
2973 * smack_socket_getpeersec_dgram - pull in packet label
2974 * @sock: the peer socket
2975 * @skb: packet data
2976 * @secid: pointer to where to put the secid of the packet
2977 *
2978 * Sets the netlabel socket state on sk from parent
2979 */
2980static int smack_socket_getpeersec_dgram(struct socket *sock,
2981 struct sk_buff *skb, u32 *secid)
2982
2983{
2984 struct netlbl_lsm_secattr secattr;
2985 struct socket_smack *sp;
2986 char smack[SMK_LABELLEN];
2987 int family = PF_UNSPEC;
2988 u32 s = 0; /* 0 is the invalid secid */
2989 int rc;
2990
2991 if (skb != NULL) {
2992 if (skb->protocol == htons(ETH_P_IP))
2993 family = PF_INET;
2994 else if (skb->protocol == htons(ETH_P_IPV6))
2995 family = PF_INET6;
2996 }
2997 if (family == PF_UNSPEC && sock != NULL)
2998 family = sock->sk->sk_family;
2999
3000 if (family == PF_UNIX) {
3001 sp = sock->sk->sk_security;
3002 s = smack_to_secid(sp->smk_out);
3003 } else if (family == PF_INET || family == PF_INET6) {
3004 /*
3005 * Translate what netlabel gave us.
3006 */
3007 netlbl_secattr_init(&secattr);
3008 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3009 if (rc == 0) {
3010 smack_from_secattr(&secattr, smack);
3011 s = smack_to_secid(smack);
3012 }
3013 netlbl_secattr_destroy(&secattr);
3014 }
3015 *secid = s;
3016 if (s == 0)
3017 return -EINVAL;
3018 return 0;
3019}
3020
3021/**
3022 * smack_sock_graft - Initialize a newly created socket with an existing sock
3023 * @sk: child sock
3024 * @parent: parent socket
3025 *
3026 * Set the smk_{in,out} state of an existing sock based on the process that
3027 * is creating the new socket.
3028 */
3029static void smack_sock_graft(struct sock *sk, struct socket *parent)
3030{
3031 struct socket_smack *ssp;
3032
3033 if (sk == NULL ||
3034 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3035 return;
3036
3037 ssp = sk->sk_security;
3038 ssp->smk_in = ssp->smk_out = smk_of_current();
3039 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
3040}
3041
3042/**
3043 * smack_inet_conn_request - Smack access check on connect
3044 * @sk: socket involved
3045 * @skb: packet
3046 * @req: unused
3047 *
3048 * Returns 0 if a task with the packet label could write to
3049 * the socket, otherwise an error code
3050 */
3051static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
3052 struct request_sock *req)
3053{
3054 u16 family = sk->sk_family;
3055 struct socket_smack *ssp = sk->sk_security;
3056 struct netlbl_lsm_secattr secattr;
3057 struct sockaddr_in addr;
3058 struct iphdr *hdr;
3059 char smack[SMK_LABELLEN];
3060 int rc;
3061 struct smk_audit_info ad;
3062
3063 /* handle mapped IPv4 packets arriving via IPv6 sockets */
3064 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
3065 family = PF_INET;
3066
3067 netlbl_secattr_init(&secattr);
3068 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3069 if (rc == 0)
3070 smack_from_secattr(&secattr, smack);
3071 else
3072 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
3073 netlbl_secattr_destroy(&secattr);
3074
3075#ifdef CONFIG_AUDIT
3076 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
3077 ad.a.u.net.family = family;
3078 ad.a.u.net.netif = skb->skb_iif;
3079 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3080#endif
3081 /*
3082 * Receiving a packet requires that the other end be able to write
3083 * here. Read access is not required.
3084 */
3085 rc = smk_access(smack, ssp->smk_in, MAY_WRITE, &ad);
3086 if (rc != 0)
3087 return rc;
3088
3089 /*
3090 * Save the peer's label in the request_sock so we can later setup
3091 * smk_packet in the child socket so that SO_PEERCRED can report it.
3092 */
3093 req->peer_secid = smack_to_secid(smack);
3094
3095 /*
3096 * We need to decide if we want to label the incoming connection here
3097 * if we do we only need to label the request_sock and the stack will
3098 * propagate the wire-label to the sock when it is created.
3099 */
3100 hdr = ip_hdr(skb);
3101 addr.sin_addr.s_addr = hdr->saddr;
3102 rcu_read_lock();
3103 if (smack_host_label(&addr) == NULL) {
3104 rcu_read_unlock();
3105 netlbl_secattr_init(&secattr);
3106 smack_to_secattr(smack, &secattr);
3107 rc = netlbl_req_setattr(req, &secattr);
3108 netlbl_secattr_destroy(&secattr);
3109 } else {
3110 rcu_read_unlock();
3111 netlbl_req_delattr(req);
3112 }
3113
3114 return rc;
3115}
3116
3117/**
3118 * smack_inet_csk_clone - Copy the connection information to the new socket
3119 * @sk: the new socket
3120 * @req: the connection's request_sock
3121 *
3122 * Transfer the connection's peer label to the newly created socket.
3123 */
3124static void smack_inet_csk_clone(struct sock *sk,
3125 const struct request_sock *req)
3126{
3127 struct socket_smack *ssp = sk->sk_security;
3128 char *smack;
3129
3130 if (req->peer_secid != 0) {
3131 smack = smack_from_secid(req->peer_secid);
3132 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
3133 } else
3134 ssp->smk_packet[0] = '\0';
3135}
3136
3137/*
3138 * Key management security hooks
3139 *
3140 * Casey has not tested key support very heavily.
3141 * The permission check is most likely too restrictive.
3142 * If you care about keys please have a look.
3143 */
3144#ifdef CONFIG_KEYS
3145
3146/**
3147 * smack_key_alloc - Set the key security blob
3148 * @key: object
3149 * @cred: the credentials to use
3150 * @flags: unused
3151 *
3152 * No allocation required
3153 *
3154 * Returns 0
3155 */
3156static int smack_key_alloc(struct key *key, const struct cred *cred,
3157 unsigned long flags)
3158{
3159 key->security = smk_of_task(cred->security);
3160 return 0;
3161}
3162
3163/**
3164 * smack_key_free - Clear the key security blob
3165 * @key: the object
3166 *
3167 * Clear the blob pointer
3168 */
3169static void smack_key_free(struct key *key)
3170{
3171 key->security = NULL;
3172}
3173
3174/*
3175 * smack_key_permission - Smack access on a key
3176 * @key_ref: gets to the object
3177 * @cred: the credentials to use
3178 * @perm: unused
3179 *
3180 * Return 0 if the task has read and write to the object,
3181 * an error code otherwise
3182 */
3183static int smack_key_permission(key_ref_t key_ref,
3184 const struct cred *cred, key_perm_t perm)
3185{
3186 struct key *keyp;
3187 struct smk_audit_info ad;
3188 char *tsp = smk_of_task(cred->security);
3189
3190 keyp = key_ref_to_ptr(key_ref);
3191 if (keyp == NULL)
3192 return -EINVAL;
3193 /*
3194 * If the key hasn't been initialized give it access so that
3195 * it may do so.
3196 */
3197 if (keyp->security == NULL)
3198 return 0;
3199 /*
3200 * This should not occur
3201 */
3202 if (tsp == NULL)
3203 return -EACCES;
3204#ifdef CONFIG_AUDIT
3205 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
3206 ad.a.u.key_struct.key = keyp->serial;
3207 ad.a.u.key_struct.key_desc = keyp->description;
3208#endif
3209 return smk_access(tsp, keyp->security,
3210 MAY_READWRITE, &ad);
3211}
3212#endif /* CONFIG_KEYS */
3213
3214/*
3215 * Smack Audit hooks
3216 *
3217 * Audit requires a unique representation of each Smack specific
3218 * rule. This unique representation is used to distinguish the
3219 * object to be audited from remaining kernel objects and also
3220 * works as a glue between the audit hooks.
3221 *
3222 * Since repository entries are added but never deleted, we'll use
3223 * the smack_known label address related to the given audit rule as
3224 * the needed unique representation. This also better fits the smack
3225 * model where nearly everything is a label.
3226 */
3227#ifdef CONFIG_AUDIT
3228
3229/**
3230 * smack_audit_rule_init - Initialize a smack audit rule
3231 * @field: audit rule fields given from user-space (audit.h)
3232 * @op: required testing operator (=, !=, >, <, ...)
3233 * @rulestr: smack label to be audited
3234 * @vrule: pointer to save our own audit rule representation
3235 *
3236 * Prepare to audit cases where (@field @op @rulestr) is true.
3237 * The label to be audited is created if necessay.
3238 */
3239static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3240{
3241 char **rule = (char **)vrule;
3242 *rule = NULL;
3243
3244 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3245 return -EINVAL;
3246
3247 if (op != Audit_equal && op != Audit_not_equal)
3248 return -EINVAL;
3249
3250 *rule = smk_import(rulestr, 0);
3251
3252 return 0;
3253}
3254
3255/**
3256 * smack_audit_rule_known - Distinguish Smack audit rules
3257 * @krule: rule of interest, in Audit kernel representation format
3258 *
3259 * This is used to filter Smack rules from remaining Audit ones.
3260 * If it's proved that this rule belongs to us, the
3261 * audit_rule_match hook will be called to do the final judgement.
3262 */
3263static int smack_audit_rule_known(struct audit_krule *krule)
3264{
3265 struct audit_field *f;
3266 int i;
3267
3268 for (i = 0; i < krule->field_count; i++) {
3269 f = &krule->fields[i];
3270
3271 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
3272 return 1;
3273 }
3274
3275 return 0;
3276}
3277
3278/**
3279 * smack_audit_rule_match - Audit given object ?
3280 * @secid: security id for identifying the object to test
3281 * @field: audit rule flags given from user-space
3282 * @op: required testing operator
3283 * @vrule: smack internal rule presentation
3284 * @actx: audit context associated with the check
3285 *
3286 * The core Audit hook. It's used to take the decision of
3287 * whether to audit or not to audit a given object.
3288 */
3289static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
3290 struct audit_context *actx)
3291{
3292 char *smack;
3293 char *rule = vrule;
3294
3295 if (!rule) {
3296 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
3297 "Smack: missing rule\n");
3298 return -ENOENT;
3299 }
3300
3301 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3302 return 0;
3303
3304 smack = smack_from_secid(secid);
3305
3306 /*
3307 * No need to do string comparisons. If a match occurs,
3308 * both pointers will point to the same smack_known
3309 * label.
3310 */
3311 if (op == Audit_equal)
3312 return (rule == smack);
3313 if (op == Audit_not_equal)
3314 return (rule != smack);
3315
3316 return 0;
3317}
3318
3319/**
3320 * smack_audit_rule_free - free smack rule representation
3321 * @vrule: rule to be freed.
3322 *
3323 * No memory was allocated.
3324 */
3325static void smack_audit_rule_free(void *vrule)
3326{
3327 /* No-op */
3328}
3329
3330#endif /* CONFIG_AUDIT */
3331
3332/**
3333 * smack_secid_to_secctx - return the smack label for a secid
3334 * @secid: incoming integer
3335 * @secdata: destination
3336 * @seclen: how long it is
3337 *
3338 * Exists for networking code.
3339 */
3340static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
3341{
3342 char *sp = smack_from_secid(secid);
3343
3344 if (secdata)
3345 *secdata = sp;
3346 *seclen = strlen(sp);
3347 return 0;
3348}
3349
3350/**
3351 * smack_secctx_to_secid - return the secid for a smack label
3352 * @secdata: smack label
3353 * @seclen: how long result is
3354 * @secid: outgoing integer
3355 *
3356 * Exists for audit and networking code.
3357 */
3358static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3359{
3360 *secid = smack_to_secid(secdata);
3361 return 0;
3362}
3363
3364/**
3365 * smack_release_secctx - don't do anything.
3366 * @secdata: unused
3367 * @seclen: unused
3368 *
3369 * Exists to make sure nothing gets done, and properly
3370 */
3371static void smack_release_secctx(char *secdata, u32 seclen)
3372{
3373}
3374
3375static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
3376{
3377 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
3378}
3379
3380static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
3381{
3382 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
3383}
3384
3385static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
3386{
3387 int len = 0;
3388 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
3389
3390 if (len < 0)
3391 return len;
3392 *ctxlen = len;
3393 return 0;
3394}
3395
3396struct security_operations smack_ops = {
3397 .name = "smack",
3398
3399 .ptrace_access_check = smack_ptrace_access_check,
3400 .ptrace_traceme = smack_ptrace_traceme,
3401 .syslog = smack_syslog,
3402
3403 .sb_alloc_security = smack_sb_alloc_security,
3404 .sb_free_security = smack_sb_free_security,
3405 .sb_copy_data = smack_sb_copy_data,
3406 .sb_kern_mount = smack_sb_kern_mount,
3407 .sb_statfs = smack_sb_statfs,
3408 .sb_mount = smack_sb_mount,
3409 .sb_umount = smack_sb_umount,
3410
3411 .bprm_set_creds = smack_bprm_set_creds,
3412
3413 .inode_alloc_security = smack_inode_alloc_security,
3414 .inode_free_security = smack_inode_free_security,
3415 .inode_init_security = smack_inode_init_security,
3416 .inode_link = smack_inode_link,
3417 .inode_unlink = smack_inode_unlink,
3418 .inode_rmdir = smack_inode_rmdir,
3419 .inode_rename = smack_inode_rename,
3420 .inode_permission = smack_inode_permission,
3421 .inode_setattr = smack_inode_setattr,
3422 .inode_getattr = smack_inode_getattr,
3423 .inode_setxattr = smack_inode_setxattr,
3424 .inode_post_setxattr = smack_inode_post_setxattr,
3425 .inode_getxattr = smack_inode_getxattr,
3426 .inode_removexattr = smack_inode_removexattr,
3427 .inode_getsecurity = smack_inode_getsecurity,
3428 .inode_setsecurity = smack_inode_setsecurity,
3429 .inode_listsecurity = smack_inode_listsecurity,
3430 .inode_getsecid = smack_inode_getsecid,
3431
3432 .file_permission = smack_file_permission,
3433 .file_alloc_security = smack_file_alloc_security,
3434 .file_free_security = smack_file_free_security,
3435 .file_ioctl = smack_file_ioctl,
3436 .file_lock = smack_file_lock,
3437 .file_fcntl = smack_file_fcntl,
3438 .file_mmap = smack_file_mmap,
3439 .file_set_fowner = smack_file_set_fowner,
3440 .file_send_sigiotask = smack_file_send_sigiotask,
3441 .file_receive = smack_file_receive,
3442
3443 .cred_alloc_blank = smack_cred_alloc_blank,
3444 .cred_free = smack_cred_free,
3445 .cred_prepare = smack_cred_prepare,
3446 .cred_transfer = smack_cred_transfer,
3447 .kernel_act_as = smack_kernel_act_as,
3448 .kernel_create_files_as = smack_kernel_create_files_as,
3449 .task_setpgid = smack_task_setpgid,
3450 .task_getpgid = smack_task_getpgid,
3451 .task_getsid = smack_task_getsid,
3452 .task_getsecid = smack_task_getsecid,
3453 .task_setnice = smack_task_setnice,
3454 .task_setioprio = smack_task_setioprio,
3455 .task_getioprio = smack_task_getioprio,
3456 .task_setscheduler = smack_task_setscheduler,
3457 .task_getscheduler = smack_task_getscheduler,
3458 .task_movememory = smack_task_movememory,
3459 .task_kill = smack_task_kill,
3460 .task_wait = smack_task_wait,
3461 .task_to_inode = smack_task_to_inode,
3462
3463 .ipc_permission = smack_ipc_permission,
3464 .ipc_getsecid = smack_ipc_getsecid,
3465
3466 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
3467 .msg_msg_free_security = smack_msg_msg_free_security,
3468
3469 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
3470 .msg_queue_free_security = smack_msg_queue_free_security,
3471 .msg_queue_associate = smack_msg_queue_associate,
3472 .msg_queue_msgctl = smack_msg_queue_msgctl,
3473 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
3474 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
3475
3476 .shm_alloc_security = smack_shm_alloc_security,
3477 .shm_free_security = smack_shm_free_security,
3478 .shm_associate = smack_shm_associate,
3479 .shm_shmctl = smack_shm_shmctl,
3480 .shm_shmat = smack_shm_shmat,
3481
3482 .sem_alloc_security = smack_sem_alloc_security,
3483 .sem_free_security = smack_sem_free_security,
3484 .sem_associate = smack_sem_associate,
3485 .sem_semctl = smack_sem_semctl,
3486 .sem_semop = smack_sem_semop,
3487
3488 .d_instantiate = smack_d_instantiate,
3489
3490 .getprocattr = smack_getprocattr,
3491 .setprocattr = smack_setprocattr,
3492
3493 .unix_stream_connect = smack_unix_stream_connect,
3494 .unix_may_send = smack_unix_may_send,
3495
3496 .socket_post_create = smack_socket_post_create,
3497 .socket_connect = smack_socket_connect,
3498 .socket_sendmsg = smack_socket_sendmsg,
3499 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
3500 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
3501 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
3502 .sk_alloc_security = smack_sk_alloc_security,
3503 .sk_free_security = smack_sk_free_security,
3504 .sock_graft = smack_sock_graft,
3505 .inet_conn_request = smack_inet_conn_request,
3506 .inet_csk_clone = smack_inet_csk_clone,
3507
3508 /* key management security hooks */
3509#ifdef CONFIG_KEYS
3510 .key_alloc = smack_key_alloc,
3511 .key_free = smack_key_free,
3512 .key_permission = smack_key_permission,
3513#endif /* CONFIG_KEYS */
3514
3515 /* Audit hooks */
3516#ifdef CONFIG_AUDIT
3517 .audit_rule_init = smack_audit_rule_init,
3518 .audit_rule_known = smack_audit_rule_known,
3519 .audit_rule_match = smack_audit_rule_match,
3520 .audit_rule_free = smack_audit_rule_free,
3521#endif /* CONFIG_AUDIT */
3522
3523 .secid_to_secctx = smack_secid_to_secctx,
3524 .secctx_to_secid = smack_secctx_to_secid,
3525 .release_secctx = smack_release_secctx,
3526 .inode_notifysecctx = smack_inode_notifysecctx,
3527 .inode_setsecctx = smack_inode_setsecctx,
3528 .inode_getsecctx = smack_inode_getsecctx,
3529};
3530
3531
3532static __init void init_smack_know_list(void)
3533{
3534 list_add(&smack_known_huh.list, &smack_known_list);
3535 list_add(&smack_known_hat.list, &smack_known_list);
3536 list_add(&smack_known_star.list, &smack_known_list);
3537 list_add(&smack_known_floor.list, &smack_known_list);
3538 list_add(&smack_known_invalid.list, &smack_known_list);
3539 list_add(&smack_known_web.list, &smack_known_list);
3540}
3541
3542/**
3543 * smack_init - initialize the smack system
3544 *
3545 * Returns 0
3546 */
3547static __init int smack_init(void)
3548{
3549 struct cred *cred;
3550 struct task_smack *tsp;
3551
3552 if (!security_module_enable(&smack_ops))
3553 return 0;
3554
3555 tsp = new_task_smack(smack_known_floor.smk_known,
3556 smack_known_floor.smk_known, GFP_KERNEL);
3557 if (tsp == NULL)
3558 return -ENOMEM;
3559
3560 printk(KERN_INFO "Smack: Initializing.\n");
3561
3562 /*
3563 * Set the security state for the initial task.
3564 */
3565 cred = (struct cred *) current->cred;
3566 cred->security = tsp;
3567
3568 /* initialize the smack_know_list */
3569 init_smack_know_list();
3570 /*
3571 * Initialize locks
3572 */
3573 spin_lock_init(&smack_known_huh.smk_cipsolock);
3574 spin_lock_init(&smack_known_hat.smk_cipsolock);
3575 spin_lock_init(&smack_known_star.smk_cipsolock);
3576 spin_lock_init(&smack_known_floor.smk_cipsolock);
3577 spin_lock_init(&smack_known_invalid.smk_cipsolock);
3578
3579 /*
3580 * Register with LSM
3581 */
3582 if (register_security(&smack_ops))
3583 panic("smack: Unable to register with kernel.\n");
3584
3585 return 0;
3586}
3587
3588/*
3589 * Smack requires early initialization in order to label
3590 * all processes and objects when they are created.
3591 */
3592security_initcall(smack_init);
1/*
2 * Simplified MAC Kernel (smack) security module
3 *
4 * This file contains the smack hook function implementations.
5 *
6 * Authors:
7 * Casey Schaufler <casey@schaufler-ca.com>
8 * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
9 *
10 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
11 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
12 * Paul Moore <paul@paul-moore.com>
13 * Copyright (C) 2010 Nokia Corporation
14 * Copyright (C) 2011 Intel Corporation.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License version 2,
18 * as published by the Free Software Foundation.
19 */
20
21#include <linux/xattr.h>
22#include <linux/pagemap.h>
23#include <linux/mount.h>
24#include <linux/stat.h>
25#include <linux/kd.h>
26#include <asm/ioctls.h>
27#include <linux/ip.h>
28#include <linux/tcp.h>
29#include <linux/udp.h>
30#include <linux/dccp.h>
31#include <linux/slab.h>
32#include <linux/mutex.h>
33#include <linux/pipe_fs_i.h>
34#include <net/cipso_ipv4.h>
35#include <net/ip.h>
36#include <net/ipv6.h>
37#include <linux/audit.h>
38#include <linux/magic.h>
39#include <linux/dcache.h>
40#include <linux/personality.h>
41#include <linux/msg.h>
42#include <linux/shm.h>
43#include <linux/binfmts.h>
44#include <linux/parser.h>
45#include "smack.h"
46
47#define TRANS_TRUE "TRUE"
48#define TRANS_TRUE_SIZE 4
49
50#define SMK_CONNECTING 0
51#define SMK_RECEIVING 1
52#define SMK_SENDING 2
53
54#ifdef SMACK_IPV6_PORT_LABELING
55static LIST_HEAD(smk_ipv6_port_list);
56#endif
57static struct kmem_cache *smack_inode_cache;
58int smack_enabled;
59
60static const match_table_t smk_mount_tokens = {
61 {Opt_fsdefault, SMK_FSDEFAULT "%s"},
62 {Opt_fsfloor, SMK_FSFLOOR "%s"},
63 {Opt_fshat, SMK_FSHAT "%s"},
64 {Opt_fsroot, SMK_FSROOT "%s"},
65 {Opt_fstransmute, SMK_FSTRANS "%s"},
66 {Opt_error, NULL},
67};
68
69#ifdef CONFIG_SECURITY_SMACK_BRINGUP
70static char *smk_bu_mess[] = {
71 "Bringup Error", /* Unused */
72 "Bringup", /* SMACK_BRINGUP_ALLOW */
73 "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */
74 "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */
75};
76
77static void smk_bu_mode(int mode, char *s)
78{
79 int i = 0;
80
81 if (mode & MAY_READ)
82 s[i++] = 'r';
83 if (mode & MAY_WRITE)
84 s[i++] = 'w';
85 if (mode & MAY_EXEC)
86 s[i++] = 'x';
87 if (mode & MAY_APPEND)
88 s[i++] = 'a';
89 if (mode & MAY_TRANSMUTE)
90 s[i++] = 't';
91 if (mode & MAY_LOCK)
92 s[i++] = 'l';
93 if (i == 0)
94 s[i++] = '-';
95 s[i] = '\0';
96}
97#endif
98
99#ifdef CONFIG_SECURITY_SMACK_BRINGUP
100static int smk_bu_note(char *note, struct smack_known *sskp,
101 struct smack_known *oskp, int mode, int rc)
102{
103 char acc[SMK_NUM_ACCESS_TYPE + 1];
104
105 if (rc <= 0)
106 return rc;
107 if (rc > SMACK_UNCONFINED_OBJECT)
108 rc = 0;
109
110 smk_bu_mode(mode, acc);
111 pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
112 sskp->smk_known, oskp->smk_known, acc, note);
113 return 0;
114}
115#else
116#define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
117#endif
118
119#ifdef CONFIG_SECURITY_SMACK_BRINGUP
120static int smk_bu_current(char *note, struct smack_known *oskp,
121 int mode, int rc)
122{
123 struct task_smack *tsp = current_security();
124 char acc[SMK_NUM_ACCESS_TYPE + 1];
125
126 if (rc <= 0)
127 return rc;
128 if (rc > SMACK_UNCONFINED_OBJECT)
129 rc = 0;
130
131 smk_bu_mode(mode, acc);
132 pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
133 tsp->smk_task->smk_known, oskp->smk_known,
134 acc, current->comm, note);
135 return 0;
136}
137#else
138#define smk_bu_current(note, oskp, mode, RC) (RC)
139#endif
140
141#ifdef CONFIG_SECURITY_SMACK_BRINGUP
142static int smk_bu_task(struct task_struct *otp, int mode, int rc)
143{
144 struct task_smack *tsp = current_security();
145 struct smack_known *smk_task = smk_of_task_struct(otp);
146 char acc[SMK_NUM_ACCESS_TYPE + 1];
147
148 if (rc <= 0)
149 return rc;
150 if (rc > SMACK_UNCONFINED_OBJECT)
151 rc = 0;
152
153 smk_bu_mode(mode, acc);
154 pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
155 tsp->smk_task->smk_known, smk_task->smk_known, acc,
156 current->comm, otp->comm);
157 return 0;
158}
159#else
160#define smk_bu_task(otp, mode, RC) (RC)
161#endif
162
163#ifdef CONFIG_SECURITY_SMACK_BRINGUP
164static int smk_bu_inode(struct inode *inode, int mode, int rc)
165{
166 struct task_smack *tsp = current_security();
167 struct inode_smack *isp = inode->i_security;
168 char acc[SMK_NUM_ACCESS_TYPE + 1];
169
170 if (isp->smk_flags & SMK_INODE_IMPURE)
171 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
172 inode->i_sb->s_id, inode->i_ino, current->comm);
173
174 if (rc <= 0)
175 return rc;
176 if (rc > SMACK_UNCONFINED_OBJECT)
177 rc = 0;
178 if (rc == SMACK_UNCONFINED_SUBJECT &&
179 (mode & (MAY_WRITE | MAY_APPEND)))
180 isp->smk_flags |= SMK_INODE_IMPURE;
181
182 smk_bu_mode(mode, acc);
183
184 pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
185 tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
186 inode->i_sb->s_id, inode->i_ino, current->comm);
187 return 0;
188}
189#else
190#define smk_bu_inode(inode, mode, RC) (RC)
191#endif
192
193#ifdef CONFIG_SECURITY_SMACK_BRINGUP
194static int smk_bu_file(struct file *file, int mode, int rc)
195{
196 struct task_smack *tsp = current_security();
197 struct smack_known *sskp = tsp->smk_task;
198 struct inode *inode = file_inode(file);
199 struct inode_smack *isp = inode->i_security;
200 char acc[SMK_NUM_ACCESS_TYPE + 1];
201
202 if (isp->smk_flags & SMK_INODE_IMPURE)
203 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
204 inode->i_sb->s_id, inode->i_ino, current->comm);
205
206 if (rc <= 0)
207 return rc;
208 if (rc > SMACK_UNCONFINED_OBJECT)
209 rc = 0;
210
211 smk_bu_mode(mode, acc);
212 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
213 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
214 inode->i_sb->s_id, inode->i_ino, file,
215 current->comm);
216 return 0;
217}
218#else
219#define smk_bu_file(file, mode, RC) (RC)
220#endif
221
222#ifdef CONFIG_SECURITY_SMACK_BRINGUP
223static int smk_bu_credfile(const struct cred *cred, struct file *file,
224 int mode, int rc)
225{
226 struct task_smack *tsp = cred->security;
227 struct smack_known *sskp = tsp->smk_task;
228 struct inode *inode = file->f_inode;
229 struct inode_smack *isp = inode->i_security;
230 char acc[SMK_NUM_ACCESS_TYPE + 1];
231
232 if (isp->smk_flags & SMK_INODE_IMPURE)
233 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
234 inode->i_sb->s_id, inode->i_ino, current->comm);
235
236 if (rc <= 0)
237 return rc;
238 if (rc > SMACK_UNCONFINED_OBJECT)
239 rc = 0;
240
241 smk_bu_mode(mode, acc);
242 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
243 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
244 inode->i_sb->s_id, inode->i_ino, file,
245 current->comm);
246 return 0;
247}
248#else
249#define smk_bu_credfile(cred, file, mode, RC) (RC)
250#endif
251
252/**
253 * smk_fetch - Fetch the smack label from a file.
254 * @name: type of the label (attribute)
255 * @ip: a pointer to the inode
256 * @dp: a pointer to the dentry
257 *
258 * Returns a pointer to the master list entry for the Smack label,
259 * NULL if there was no label to fetch, or an error code.
260 */
261static struct smack_known *smk_fetch(const char *name, struct inode *ip,
262 struct dentry *dp)
263{
264 int rc;
265 char *buffer;
266 struct smack_known *skp = NULL;
267
268 if (ip->i_op->getxattr == NULL)
269 return ERR_PTR(-EOPNOTSUPP);
270
271 buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL);
272 if (buffer == NULL)
273 return ERR_PTR(-ENOMEM);
274
275 rc = ip->i_op->getxattr(dp, name, buffer, SMK_LONGLABEL);
276 if (rc < 0)
277 skp = ERR_PTR(rc);
278 else if (rc == 0)
279 skp = NULL;
280 else
281 skp = smk_import_entry(buffer, rc);
282
283 kfree(buffer);
284
285 return skp;
286}
287
288/**
289 * new_inode_smack - allocate an inode security blob
290 * @skp: a pointer to the Smack label entry to use in the blob
291 *
292 * Returns the new blob or NULL if there's no memory available
293 */
294static struct inode_smack *new_inode_smack(struct smack_known *skp)
295{
296 struct inode_smack *isp;
297
298 isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS);
299 if (isp == NULL)
300 return NULL;
301
302 isp->smk_inode = skp;
303 isp->smk_flags = 0;
304 mutex_init(&isp->smk_lock);
305
306 return isp;
307}
308
309/**
310 * new_task_smack - allocate a task security blob
311 * @task: a pointer to the Smack label for the running task
312 * @forked: a pointer to the Smack label for the forked task
313 * @gfp: type of the memory for the allocation
314 *
315 * Returns the new blob or NULL if there's no memory available
316 */
317static struct task_smack *new_task_smack(struct smack_known *task,
318 struct smack_known *forked, gfp_t gfp)
319{
320 struct task_smack *tsp;
321
322 tsp = kzalloc(sizeof(struct task_smack), gfp);
323 if (tsp == NULL)
324 return NULL;
325
326 tsp->smk_task = task;
327 tsp->smk_forked = forked;
328 INIT_LIST_HEAD(&tsp->smk_rules);
329 INIT_LIST_HEAD(&tsp->smk_relabel);
330 mutex_init(&tsp->smk_rules_lock);
331
332 return tsp;
333}
334
335/**
336 * smk_copy_rules - copy a rule set
337 * @nhead: new rules header pointer
338 * @ohead: old rules header pointer
339 * @gfp: type of the memory for the allocation
340 *
341 * Returns 0 on success, -ENOMEM on error
342 */
343static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
344 gfp_t gfp)
345{
346 struct smack_rule *nrp;
347 struct smack_rule *orp;
348 int rc = 0;
349
350 INIT_LIST_HEAD(nhead);
351
352 list_for_each_entry_rcu(orp, ohead, list) {
353 nrp = kzalloc(sizeof(struct smack_rule), gfp);
354 if (nrp == NULL) {
355 rc = -ENOMEM;
356 break;
357 }
358 *nrp = *orp;
359 list_add_rcu(&nrp->list, nhead);
360 }
361 return rc;
362}
363
364/**
365 * smk_copy_relabel - copy smk_relabel labels list
366 * @nhead: new rules header pointer
367 * @ohead: old rules header pointer
368 * @gfp: type of the memory for the allocation
369 *
370 * Returns 0 on success, -ENOMEM on error
371 */
372static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
373 gfp_t gfp)
374{
375 struct smack_known_list_elem *nklep;
376 struct smack_known_list_elem *oklep;
377
378 INIT_LIST_HEAD(nhead);
379
380 list_for_each_entry(oklep, ohead, list) {
381 nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
382 if (nklep == NULL) {
383 smk_destroy_label_list(nhead);
384 return -ENOMEM;
385 }
386 nklep->smk_label = oklep->smk_label;
387 list_add(&nklep->list, nhead);
388 }
389
390 return 0;
391}
392
393/**
394 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
395 * @mode - input mode in form of PTRACE_MODE_*
396 *
397 * Returns a converted MAY_* mode usable by smack rules
398 */
399static inline unsigned int smk_ptrace_mode(unsigned int mode)
400{
401 if (mode & PTRACE_MODE_ATTACH)
402 return MAY_READWRITE;
403 if (mode & PTRACE_MODE_READ)
404 return MAY_READ;
405
406 return 0;
407}
408
409/**
410 * smk_ptrace_rule_check - helper for ptrace access
411 * @tracer: tracer process
412 * @tracee_known: label entry of the process that's about to be traced
413 * @mode: ptrace attachment mode (PTRACE_MODE_*)
414 * @func: name of the function that called us, used for audit
415 *
416 * Returns 0 on access granted, -error on error
417 */
418static int smk_ptrace_rule_check(struct task_struct *tracer,
419 struct smack_known *tracee_known,
420 unsigned int mode, const char *func)
421{
422 int rc;
423 struct smk_audit_info ad, *saip = NULL;
424 struct task_smack *tsp;
425 struct smack_known *tracer_known;
426
427 if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
428 smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
429 smk_ad_setfield_u_tsk(&ad, tracer);
430 saip = &ad;
431 }
432
433 rcu_read_lock();
434 tsp = __task_cred(tracer)->security;
435 tracer_known = smk_of_task(tsp);
436
437 if ((mode & PTRACE_MODE_ATTACH) &&
438 (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
439 smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
440 if (tracer_known->smk_known == tracee_known->smk_known)
441 rc = 0;
442 else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
443 rc = -EACCES;
444 else if (capable(CAP_SYS_PTRACE))
445 rc = 0;
446 else
447 rc = -EACCES;
448
449 if (saip)
450 smack_log(tracer_known->smk_known,
451 tracee_known->smk_known,
452 0, rc, saip);
453
454 rcu_read_unlock();
455 return rc;
456 }
457
458 /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
459 rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
460
461 rcu_read_unlock();
462 return rc;
463}
464
465/*
466 * LSM hooks.
467 * We he, that is fun!
468 */
469
470/**
471 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
472 * @ctp: child task pointer
473 * @mode: ptrace attachment mode (PTRACE_MODE_*)
474 *
475 * Returns 0 if access is OK, an error code otherwise
476 *
477 * Do the capability checks.
478 */
479static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
480{
481 struct smack_known *skp;
482
483 skp = smk_of_task_struct(ctp);
484
485 return smk_ptrace_rule_check(current, skp, mode, __func__);
486}
487
488/**
489 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
490 * @ptp: parent task pointer
491 *
492 * Returns 0 if access is OK, an error code otherwise
493 *
494 * Do the capability checks, and require PTRACE_MODE_ATTACH.
495 */
496static int smack_ptrace_traceme(struct task_struct *ptp)
497{
498 int rc;
499 struct smack_known *skp;
500
501 skp = smk_of_task(current_security());
502
503 rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
504 return rc;
505}
506
507/**
508 * smack_syslog - Smack approval on syslog
509 * @type: message type
510 *
511 * Returns 0 on success, error code otherwise.
512 */
513static int smack_syslog(int typefrom_file)
514{
515 int rc = 0;
516 struct smack_known *skp = smk_of_current();
517
518 if (smack_privileged(CAP_MAC_OVERRIDE))
519 return 0;
520
521 if (smack_syslog_label != NULL && smack_syslog_label != skp)
522 rc = -EACCES;
523
524 return rc;
525}
526
527
528/*
529 * Superblock Hooks.
530 */
531
532/**
533 * smack_sb_alloc_security - allocate a superblock blob
534 * @sb: the superblock getting the blob
535 *
536 * Returns 0 on success or -ENOMEM on error.
537 */
538static int smack_sb_alloc_security(struct super_block *sb)
539{
540 struct superblock_smack *sbsp;
541
542 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
543
544 if (sbsp == NULL)
545 return -ENOMEM;
546
547 sbsp->smk_root = &smack_known_floor;
548 sbsp->smk_default = &smack_known_floor;
549 sbsp->smk_floor = &smack_known_floor;
550 sbsp->smk_hat = &smack_known_hat;
551 /*
552 * smk_initialized will be zero from kzalloc.
553 */
554 sb->s_security = sbsp;
555
556 return 0;
557}
558
559/**
560 * smack_sb_free_security - free a superblock blob
561 * @sb: the superblock getting the blob
562 *
563 */
564static void smack_sb_free_security(struct super_block *sb)
565{
566 kfree(sb->s_security);
567 sb->s_security = NULL;
568}
569
570/**
571 * smack_sb_copy_data - copy mount options data for processing
572 * @orig: where to start
573 * @smackopts: mount options string
574 *
575 * Returns 0 on success or -ENOMEM on error.
576 *
577 * Copy the Smack specific mount options out of the mount
578 * options list.
579 */
580static int smack_sb_copy_data(char *orig, char *smackopts)
581{
582 char *cp, *commap, *otheropts, *dp;
583
584 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
585 if (otheropts == NULL)
586 return -ENOMEM;
587
588 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
589 if (strstr(cp, SMK_FSDEFAULT) == cp)
590 dp = smackopts;
591 else if (strstr(cp, SMK_FSFLOOR) == cp)
592 dp = smackopts;
593 else if (strstr(cp, SMK_FSHAT) == cp)
594 dp = smackopts;
595 else if (strstr(cp, SMK_FSROOT) == cp)
596 dp = smackopts;
597 else if (strstr(cp, SMK_FSTRANS) == cp)
598 dp = smackopts;
599 else
600 dp = otheropts;
601
602 commap = strchr(cp, ',');
603 if (commap != NULL)
604 *commap = '\0';
605
606 if (*dp != '\0')
607 strcat(dp, ",");
608 strcat(dp, cp);
609 }
610
611 strcpy(orig, otheropts);
612 free_page((unsigned long)otheropts);
613
614 return 0;
615}
616
617/**
618 * smack_parse_opts_str - parse Smack specific mount options
619 * @options: mount options string
620 * @opts: where to store converted mount opts
621 *
622 * Returns 0 on success or -ENOMEM on error.
623 *
624 * converts Smack specific mount options to generic security option format
625 */
626static int smack_parse_opts_str(char *options,
627 struct security_mnt_opts *opts)
628{
629 char *p;
630 char *fsdefault = NULL;
631 char *fsfloor = NULL;
632 char *fshat = NULL;
633 char *fsroot = NULL;
634 char *fstransmute = NULL;
635 int rc = -ENOMEM;
636 int num_mnt_opts = 0;
637 int token;
638
639 opts->num_mnt_opts = 0;
640
641 if (!options)
642 return 0;
643
644 while ((p = strsep(&options, ",")) != NULL) {
645 substring_t args[MAX_OPT_ARGS];
646
647 if (!*p)
648 continue;
649
650 token = match_token(p, smk_mount_tokens, args);
651
652 switch (token) {
653 case Opt_fsdefault:
654 if (fsdefault)
655 goto out_opt_err;
656 fsdefault = match_strdup(&args[0]);
657 if (!fsdefault)
658 goto out_err;
659 break;
660 case Opt_fsfloor:
661 if (fsfloor)
662 goto out_opt_err;
663 fsfloor = match_strdup(&args[0]);
664 if (!fsfloor)
665 goto out_err;
666 break;
667 case Opt_fshat:
668 if (fshat)
669 goto out_opt_err;
670 fshat = match_strdup(&args[0]);
671 if (!fshat)
672 goto out_err;
673 break;
674 case Opt_fsroot:
675 if (fsroot)
676 goto out_opt_err;
677 fsroot = match_strdup(&args[0]);
678 if (!fsroot)
679 goto out_err;
680 break;
681 case Opt_fstransmute:
682 if (fstransmute)
683 goto out_opt_err;
684 fstransmute = match_strdup(&args[0]);
685 if (!fstransmute)
686 goto out_err;
687 break;
688 default:
689 rc = -EINVAL;
690 pr_warn("Smack: unknown mount option\n");
691 goto out_err;
692 }
693 }
694
695 opts->mnt_opts = kcalloc(NUM_SMK_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
696 if (!opts->mnt_opts)
697 goto out_err;
698
699 opts->mnt_opts_flags = kcalloc(NUM_SMK_MNT_OPTS, sizeof(int),
700 GFP_ATOMIC);
701 if (!opts->mnt_opts_flags) {
702 kfree(opts->mnt_opts);
703 goto out_err;
704 }
705
706 if (fsdefault) {
707 opts->mnt_opts[num_mnt_opts] = fsdefault;
708 opts->mnt_opts_flags[num_mnt_opts++] = FSDEFAULT_MNT;
709 }
710 if (fsfloor) {
711 opts->mnt_opts[num_mnt_opts] = fsfloor;
712 opts->mnt_opts_flags[num_mnt_opts++] = FSFLOOR_MNT;
713 }
714 if (fshat) {
715 opts->mnt_opts[num_mnt_opts] = fshat;
716 opts->mnt_opts_flags[num_mnt_opts++] = FSHAT_MNT;
717 }
718 if (fsroot) {
719 opts->mnt_opts[num_mnt_opts] = fsroot;
720 opts->mnt_opts_flags[num_mnt_opts++] = FSROOT_MNT;
721 }
722 if (fstransmute) {
723 opts->mnt_opts[num_mnt_opts] = fstransmute;
724 opts->mnt_opts_flags[num_mnt_opts++] = FSTRANS_MNT;
725 }
726
727 opts->num_mnt_opts = num_mnt_opts;
728 return 0;
729
730out_opt_err:
731 rc = -EINVAL;
732 pr_warn("Smack: duplicate mount options\n");
733
734out_err:
735 kfree(fsdefault);
736 kfree(fsfloor);
737 kfree(fshat);
738 kfree(fsroot);
739 kfree(fstransmute);
740 return rc;
741}
742
743/**
744 * smack_set_mnt_opts - set Smack specific mount options
745 * @sb: the file system superblock
746 * @opts: Smack mount options
747 * @kern_flags: mount option from kernel space or user space
748 * @set_kern_flags: where to store converted mount opts
749 *
750 * Returns 0 on success, an error code on failure
751 *
752 * Allow filesystems with binary mount data to explicitly set Smack mount
753 * labels.
754 */
755static int smack_set_mnt_opts(struct super_block *sb,
756 struct security_mnt_opts *opts,
757 unsigned long kern_flags,
758 unsigned long *set_kern_flags)
759{
760 struct dentry *root = sb->s_root;
761 struct inode *inode = d_backing_inode(root);
762 struct superblock_smack *sp = sb->s_security;
763 struct inode_smack *isp;
764 struct smack_known *skp;
765 int i;
766 int num_opts = opts->num_mnt_opts;
767 int transmute = 0;
768
769 if (sp->smk_initialized)
770 return 0;
771
772 sp->smk_initialized = 1;
773
774 for (i = 0; i < num_opts; i++) {
775 switch (opts->mnt_opts_flags[i]) {
776 case FSDEFAULT_MNT:
777 skp = smk_import_entry(opts->mnt_opts[i], 0);
778 if (IS_ERR(skp))
779 return PTR_ERR(skp);
780 sp->smk_default = skp;
781 break;
782 case FSFLOOR_MNT:
783 skp = smk_import_entry(opts->mnt_opts[i], 0);
784 if (IS_ERR(skp))
785 return PTR_ERR(skp);
786 sp->smk_floor = skp;
787 break;
788 case FSHAT_MNT:
789 skp = smk_import_entry(opts->mnt_opts[i], 0);
790 if (IS_ERR(skp))
791 return PTR_ERR(skp);
792 sp->smk_hat = skp;
793 break;
794 case FSROOT_MNT:
795 skp = smk_import_entry(opts->mnt_opts[i], 0);
796 if (IS_ERR(skp))
797 return PTR_ERR(skp);
798 sp->smk_root = skp;
799 break;
800 case FSTRANS_MNT:
801 skp = smk_import_entry(opts->mnt_opts[i], 0);
802 if (IS_ERR(skp))
803 return PTR_ERR(skp);
804 sp->smk_root = skp;
805 transmute = 1;
806 break;
807 default:
808 break;
809 }
810 }
811
812 if (!smack_privileged(CAP_MAC_ADMIN)) {
813 /*
814 * Unprivileged mounts don't get to specify Smack values.
815 */
816 if (num_opts)
817 return -EPERM;
818 /*
819 * Unprivileged mounts get root and default from the caller.
820 */
821 skp = smk_of_current();
822 sp->smk_root = skp;
823 sp->smk_default = skp;
824 }
825
826 /*
827 * Initialize the root inode.
828 */
829 isp = inode->i_security;
830 if (isp == NULL) {
831 isp = new_inode_smack(sp->smk_root);
832 if (isp == NULL)
833 return -ENOMEM;
834 inode->i_security = isp;
835 } else
836 isp->smk_inode = sp->smk_root;
837
838 if (transmute)
839 isp->smk_flags |= SMK_INODE_TRANSMUTE;
840
841 return 0;
842}
843
844/**
845 * smack_sb_kern_mount - Smack specific mount processing
846 * @sb: the file system superblock
847 * @flags: the mount flags
848 * @data: the smack mount options
849 *
850 * Returns 0 on success, an error code on failure
851 */
852static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
853{
854 int rc = 0;
855 char *options = data;
856 struct security_mnt_opts opts;
857
858 security_init_mnt_opts(&opts);
859
860 if (!options)
861 goto out;
862
863 rc = smack_parse_opts_str(options, &opts);
864 if (rc)
865 goto out_err;
866
867out:
868 rc = smack_set_mnt_opts(sb, &opts, 0, NULL);
869
870out_err:
871 security_free_mnt_opts(&opts);
872 return rc;
873}
874
875/**
876 * smack_sb_statfs - Smack check on statfs
877 * @dentry: identifies the file system in question
878 *
879 * Returns 0 if current can read the floor of the filesystem,
880 * and error code otherwise
881 */
882static int smack_sb_statfs(struct dentry *dentry)
883{
884 struct superblock_smack *sbp = dentry->d_sb->s_security;
885 int rc;
886 struct smk_audit_info ad;
887
888 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
889 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
890
891 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
892 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
893 return rc;
894}
895
896/*
897 * BPRM hooks
898 */
899
900/**
901 * smack_bprm_set_creds - set creds for exec
902 * @bprm: the exec information
903 *
904 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
905 */
906static int smack_bprm_set_creds(struct linux_binprm *bprm)
907{
908 struct inode *inode = file_inode(bprm->file);
909 struct task_smack *bsp = bprm->cred->security;
910 struct inode_smack *isp;
911 int rc;
912
913 if (bprm->cred_prepared)
914 return 0;
915
916 isp = inode->i_security;
917 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
918 return 0;
919
920 if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
921 struct task_struct *tracer;
922 rc = 0;
923
924 rcu_read_lock();
925 tracer = ptrace_parent(current);
926 if (likely(tracer != NULL))
927 rc = smk_ptrace_rule_check(tracer,
928 isp->smk_task,
929 PTRACE_MODE_ATTACH,
930 __func__);
931 rcu_read_unlock();
932
933 if (rc != 0)
934 return rc;
935 } else if (bprm->unsafe)
936 return -EPERM;
937
938 bsp->smk_task = isp->smk_task;
939 bprm->per_clear |= PER_CLEAR_ON_SETID;
940
941 return 0;
942}
943
944/**
945 * smack_bprm_committing_creds - Prepare to install the new credentials
946 * from bprm.
947 *
948 * @bprm: binprm for exec
949 */
950static void smack_bprm_committing_creds(struct linux_binprm *bprm)
951{
952 struct task_smack *bsp = bprm->cred->security;
953
954 if (bsp->smk_task != bsp->smk_forked)
955 current->pdeath_signal = 0;
956}
957
958/**
959 * smack_bprm_secureexec - Return the decision to use secureexec.
960 * @bprm: binprm for exec
961 *
962 * Returns 0 on success.
963 */
964static int smack_bprm_secureexec(struct linux_binprm *bprm)
965{
966 struct task_smack *tsp = current_security();
967
968 if (tsp->smk_task != tsp->smk_forked)
969 return 1;
970
971 return 0;
972}
973
974/*
975 * Inode hooks
976 */
977
978/**
979 * smack_inode_alloc_security - allocate an inode blob
980 * @inode: the inode in need of a blob
981 *
982 * Returns 0 if it gets a blob, -ENOMEM otherwise
983 */
984static int smack_inode_alloc_security(struct inode *inode)
985{
986 struct smack_known *skp = smk_of_current();
987
988 inode->i_security = new_inode_smack(skp);
989 if (inode->i_security == NULL)
990 return -ENOMEM;
991 return 0;
992}
993
994/**
995 * smack_inode_free_security - free an inode blob
996 * @inode: the inode with a blob
997 *
998 * Clears the blob pointer in inode
999 */
1000static void smack_inode_free_security(struct inode *inode)
1001{
1002 kmem_cache_free(smack_inode_cache, inode->i_security);
1003 inode->i_security = NULL;
1004}
1005
1006/**
1007 * smack_inode_init_security - copy out the smack from an inode
1008 * @inode: the newly created inode
1009 * @dir: containing directory object
1010 * @qstr: unused
1011 * @name: where to put the attribute name
1012 * @value: where to put the attribute value
1013 * @len: where to put the length of the attribute
1014 *
1015 * Returns 0 if it all works out, -ENOMEM if there's no memory
1016 */
1017static int smack_inode_init_security(struct inode *inode, struct inode *dir,
1018 const struct qstr *qstr, const char **name,
1019 void **value, size_t *len)
1020{
1021 struct inode_smack *issp = inode->i_security;
1022 struct smack_known *skp = smk_of_current();
1023 struct smack_known *isp = smk_of_inode(inode);
1024 struct smack_known *dsp = smk_of_inode(dir);
1025 int may;
1026
1027 if (name)
1028 *name = XATTR_SMACK_SUFFIX;
1029
1030 if (value && len) {
1031 rcu_read_lock();
1032 may = smk_access_entry(skp->smk_known, dsp->smk_known,
1033 &skp->smk_rules);
1034 rcu_read_unlock();
1035
1036 /*
1037 * If the access rule allows transmutation and
1038 * the directory requests transmutation then
1039 * by all means transmute.
1040 * Mark the inode as changed.
1041 */
1042 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
1043 smk_inode_transmutable(dir)) {
1044 isp = dsp;
1045 issp->smk_flags |= SMK_INODE_CHANGED;
1046 }
1047
1048 *value = kstrdup(isp->smk_known, GFP_NOFS);
1049 if (*value == NULL)
1050 return -ENOMEM;
1051
1052 *len = strlen(isp->smk_known);
1053 }
1054
1055 return 0;
1056}
1057
1058/**
1059 * smack_inode_link - Smack check on link
1060 * @old_dentry: the existing object
1061 * @dir: unused
1062 * @new_dentry: the new object
1063 *
1064 * Returns 0 if access is permitted, an error code otherwise
1065 */
1066static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1067 struct dentry *new_dentry)
1068{
1069 struct smack_known *isp;
1070 struct smk_audit_info ad;
1071 int rc;
1072
1073 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1074 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1075
1076 isp = smk_of_inode(d_backing_inode(old_dentry));
1077 rc = smk_curacc(isp, MAY_WRITE, &ad);
1078 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1079
1080 if (rc == 0 && d_is_positive(new_dentry)) {
1081 isp = smk_of_inode(d_backing_inode(new_dentry));
1082 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1083 rc = smk_curacc(isp, MAY_WRITE, &ad);
1084 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1085 }
1086
1087 return rc;
1088}
1089
1090/**
1091 * smack_inode_unlink - Smack check on inode deletion
1092 * @dir: containing directory object
1093 * @dentry: file to unlink
1094 *
1095 * Returns 0 if current can write the containing directory
1096 * and the object, error code otherwise
1097 */
1098static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1099{
1100 struct inode *ip = d_backing_inode(dentry);
1101 struct smk_audit_info ad;
1102 int rc;
1103
1104 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1105 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1106
1107 /*
1108 * You need write access to the thing you're unlinking
1109 */
1110 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1111 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1112 if (rc == 0) {
1113 /*
1114 * You also need write access to the containing directory
1115 */
1116 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1117 smk_ad_setfield_u_fs_inode(&ad, dir);
1118 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1119 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1120 }
1121 return rc;
1122}
1123
1124/**
1125 * smack_inode_rmdir - Smack check on directory deletion
1126 * @dir: containing directory object
1127 * @dentry: directory to unlink
1128 *
1129 * Returns 0 if current can write the containing directory
1130 * and the directory, error code otherwise
1131 */
1132static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1133{
1134 struct smk_audit_info ad;
1135 int rc;
1136
1137 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1138 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1139
1140 /*
1141 * You need write access to the thing you're removing
1142 */
1143 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1144 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1145 if (rc == 0) {
1146 /*
1147 * You also need write access to the containing directory
1148 */
1149 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1150 smk_ad_setfield_u_fs_inode(&ad, dir);
1151 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1152 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1153 }
1154
1155 return rc;
1156}
1157
1158/**
1159 * smack_inode_rename - Smack check on rename
1160 * @old_inode: unused
1161 * @old_dentry: the old object
1162 * @new_inode: unused
1163 * @new_dentry: the new object
1164 *
1165 * Read and write access is required on both the old and
1166 * new directories.
1167 *
1168 * Returns 0 if access is permitted, an error code otherwise
1169 */
1170static int smack_inode_rename(struct inode *old_inode,
1171 struct dentry *old_dentry,
1172 struct inode *new_inode,
1173 struct dentry *new_dentry)
1174{
1175 int rc;
1176 struct smack_known *isp;
1177 struct smk_audit_info ad;
1178
1179 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1180 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1181
1182 isp = smk_of_inode(d_backing_inode(old_dentry));
1183 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1184 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1185
1186 if (rc == 0 && d_is_positive(new_dentry)) {
1187 isp = smk_of_inode(d_backing_inode(new_dentry));
1188 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1189 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1190 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1191 }
1192 return rc;
1193}
1194
1195/**
1196 * smack_inode_permission - Smack version of permission()
1197 * @inode: the inode in question
1198 * @mask: the access requested
1199 *
1200 * This is the important Smack hook.
1201 *
1202 * Returns 0 if access is permitted, -EACCES otherwise
1203 */
1204static int smack_inode_permission(struct inode *inode, int mask)
1205{
1206 struct smk_audit_info ad;
1207 int no_block = mask & MAY_NOT_BLOCK;
1208 int rc;
1209
1210 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1211 /*
1212 * No permission to check. Existence test. Yup, it's there.
1213 */
1214 if (mask == 0)
1215 return 0;
1216
1217 /* May be droppable after audit */
1218 if (no_block)
1219 return -ECHILD;
1220 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1221 smk_ad_setfield_u_fs_inode(&ad, inode);
1222 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1223 rc = smk_bu_inode(inode, mask, rc);
1224 return rc;
1225}
1226
1227/**
1228 * smack_inode_setattr - Smack check for setting attributes
1229 * @dentry: the object
1230 * @iattr: for the force flag
1231 *
1232 * Returns 0 if access is permitted, an error code otherwise
1233 */
1234static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
1235{
1236 struct smk_audit_info ad;
1237 int rc;
1238
1239 /*
1240 * Need to allow for clearing the setuid bit.
1241 */
1242 if (iattr->ia_valid & ATTR_FORCE)
1243 return 0;
1244 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1245 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1246
1247 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1248 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1249 return rc;
1250}
1251
1252/**
1253 * smack_inode_getattr - Smack check for getting attributes
1254 * @mnt: vfsmount of the object
1255 * @dentry: the object
1256 *
1257 * Returns 0 if access is permitted, an error code otherwise
1258 */
1259static int smack_inode_getattr(const struct path *path)
1260{
1261 struct smk_audit_info ad;
1262 struct inode *inode = d_backing_inode(path->dentry);
1263 int rc;
1264
1265 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1266 smk_ad_setfield_u_fs_path(&ad, *path);
1267 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1268 rc = smk_bu_inode(inode, MAY_READ, rc);
1269 return rc;
1270}
1271
1272/**
1273 * smack_inode_setxattr - Smack check for setting xattrs
1274 * @dentry: the object
1275 * @name: name of the attribute
1276 * @value: value of the attribute
1277 * @size: size of the value
1278 * @flags: unused
1279 *
1280 * This protects the Smack attribute explicitly.
1281 *
1282 * Returns 0 if access is permitted, an error code otherwise
1283 */
1284static int smack_inode_setxattr(struct dentry *dentry, const char *name,
1285 const void *value, size_t size, int flags)
1286{
1287 struct smk_audit_info ad;
1288 struct smack_known *skp;
1289 int check_priv = 0;
1290 int check_import = 0;
1291 int check_star = 0;
1292 int rc = 0;
1293
1294 /*
1295 * Check label validity here so import won't fail in post_setxattr
1296 */
1297 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1298 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1299 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1300 check_priv = 1;
1301 check_import = 1;
1302 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1303 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1304 check_priv = 1;
1305 check_import = 1;
1306 check_star = 1;
1307 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1308 check_priv = 1;
1309 if (size != TRANS_TRUE_SIZE ||
1310 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1311 rc = -EINVAL;
1312 } else
1313 rc = cap_inode_setxattr(dentry, name, value, size, flags);
1314
1315 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1316 rc = -EPERM;
1317
1318 if (rc == 0 && check_import) {
1319 skp = size ? smk_import_entry(value, size) : NULL;
1320 if (IS_ERR(skp))
1321 rc = PTR_ERR(skp);
1322 else if (skp == NULL || (check_star &&
1323 (skp == &smack_known_star || skp == &smack_known_web)))
1324 rc = -EINVAL;
1325 }
1326
1327 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1328 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1329
1330 if (rc == 0) {
1331 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1332 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1333 }
1334
1335 return rc;
1336}
1337
1338/**
1339 * smack_inode_post_setxattr - Apply the Smack update approved above
1340 * @dentry: object
1341 * @name: attribute name
1342 * @value: attribute value
1343 * @size: attribute size
1344 * @flags: unused
1345 *
1346 * Set the pointer in the inode blob to the entry found
1347 * in the master label list.
1348 */
1349static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1350 const void *value, size_t size, int flags)
1351{
1352 struct smack_known *skp;
1353 struct inode_smack *isp = d_backing_inode(dentry)->i_security;
1354
1355 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1356 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1357 return;
1358 }
1359
1360 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1361 skp = smk_import_entry(value, size);
1362 if (!IS_ERR(skp))
1363 isp->smk_inode = skp;
1364 else
1365 isp->smk_inode = &smack_known_invalid;
1366 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1367 skp = smk_import_entry(value, size);
1368 if (!IS_ERR(skp))
1369 isp->smk_task = skp;
1370 else
1371 isp->smk_task = &smack_known_invalid;
1372 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1373 skp = smk_import_entry(value, size);
1374 if (!IS_ERR(skp))
1375 isp->smk_mmap = skp;
1376 else
1377 isp->smk_mmap = &smack_known_invalid;
1378 }
1379
1380 return;
1381}
1382
1383/**
1384 * smack_inode_getxattr - Smack check on getxattr
1385 * @dentry: the object
1386 * @name: unused
1387 *
1388 * Returns 0 if access is permitted, an error code otherwise
1389 */
1390static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1391{
1392 struct smk_audit_info ad;
1393 int rc;
1394
1395 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1396 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1397
1398 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1399 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1400 return rc;
1401}
1402
1403/**
1404 * smack_inode_removexattr - Smack check on removexattr
1405 * @dentry: the object
1406 * @name: name of the attribute
1407 *
1408 * Removing the Smack attribute requires CAP_MAC_ADMIN
1409 *
1410 * Returns 0 if access is permitted, an error code otherwise
1411 */
1412static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1413{
1414 struct inode_smack *isp;
1415 struct smk_audit_info ad;
1416 int rc = 0;
1417
1418 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1419 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1420 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1421 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1422 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1423 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1424 if (!smack_privileged(CAP_MAC_ADMIN))
1425 rc = -EPERM;
1426 } else
1427 rc = cap_inode_removexattr(dentry, name);
1428
1429 if (rc != 0)
1430 return rc;
1431
1432 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1433 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1434
1435 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1436 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1437 if (rc != 0)
1438 return rc;
1439
1440 isp = d_backing_inode(dentry)->i_security;
1441 /*
1442 * Don't do anything special for these.
1443 * XATTR_NAME_SMACKIPIN
1444 * XATTR_NAME_SMACKIPOUT
1445 */
1446 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1447 struct super_block *sbp = d_backing_inode(dentry)->i_sb;
1448 struct superblock_smack *sbsp = sbp->s_security;
1449
1450 isp->smk_inode = sbsp->smk_default;
1451 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1452 isp->smk_task = NULL;
1453 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1454 isp->smk_mmap = NULL;
1455 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1456 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1457
1458 return 0;
1459}
1460
1461/**
1462 * smack_inode_getsecurity - get smack xattrs
1463 * @inode: the object
1464 * @name: attribute name
1465 * @buffer: where to put the result
1466 * @alloc: unused
1467 *
1468 * Returns the size of the attribute or an error code
1469 */
1470static int smack_inode_getsecurity(struct inode *inode,
1471 const char *name, void **buffer,
1472 bool alloc)
1473{
1474 struct socket_smack *ssp;
1475 struct socket *sock;
1476 struct super_block *sbp;
1477 struct inode *ip = (struct inode *)inode;
1478 struct smack_known *isp;
1479 int ilen;
1480 int rc = 0;
1481
1482 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1483 isp = smk_of_inode(inode);
1484 ilen = strlen(isp->smk_known);
1485 *buffer = isp->smk_known;
1486 return ilen;
1487 }
1488
1489 /*
1490 * The rest of the Smack xattrs are only on sockets.
1491 */
1492 sbp = ip->i_sb;
1493 if (sbp->s_magic != SOCKFS_MAGIC)
1494 return -EOPNOTSUPP;
1495
1496 sock = SOCKET_I(ip);
1497 if (sock == NULL || sock->sk == NULL)
1498 return -EOPNOTSUPP;
1499
1500 ssp = sock->sk->sk_security;
1501
1502 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1503 isp = ssp->smk_in;
1504 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1505 isp = ssp->smk_out;
1506 else
1507 return -EOPNOTSUPP;
1508
1509 ilen = strlen(isp->smk_known);
1510 if (rc == 0) {
1511 *buffer = isp->smk_known;
1512 rc = ilen;
1513 }
1514
1515 return rc;
1516}
1517
1518
1519/**
1520 * smack_inode_listsecurity - list the Smack attributes
1521 * @inode: the object
1522 * @buffer: where they go
1523 * @buffer_size: size of buffer
1524 */
1525static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1526 size_t buffer_size)
1527{
1528 int len = sizeof(XATTR_NAME_SMACK);
1529
1530 if (buffer != NULL && len <= buffer_size)
1531 memcpy(buffer, XATTR_NAME_SMACK, len);
1532
1533 return len;
1534}
1535
1536/**
1537 * smack_inode_getsecid - Extract inode's security id
1538 * @inode: inode to extract the info from
1539 * @secid: where result will be saved
1540 */
1541static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1542{
1543 struct inode_smack *isp = inode->i_security;
1544
1545 *secid = isp->smk_inode->smk_secid;
1546}
1547
1548/*
1549 * File Hooks
1550 */
1551
1552/*
1553 * There is no smack_file_permission hook
1554 *
1555 * Should access checks be done on each read or write?
1556 * UNICOS and SELinux say yes.
1557 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1558 *
1559 * I'll say no for now. Smack does not do the frequent
1560 * label changing that SELinux does.
1561 */
1562
1563/**
1564 * smack_file_alloc_security - assign a file security blob
1565 * @file: the object
1566 *
1567 * The security blob for a file is a pointer to the master
1568 * label list, so no allocation is done.
1569 *
1570 * f_security is the owner security information. It
1571 * isn't used on file access checks, it's for send_sigio.
1572 *
1573 * Returns 0
1574 */
1575static int smack_file_alloc_security(struct file *file)
1576{
1577 struct smack_known *skp = smk_of_current();
1578
1579 file->f_security = skp;
1580 return 0;
1581}
1582
1583/**
1584 * smack_file_free_security - clear a file security blob
1585 * @file: the object
1586 *
1587 * The security blob for a file is a pointer to the master
1588 * label list, so no memory is freed.
1589 */
1590static void smack_file_free_security(struct file *file)
1591{
1592 file->f_security = NULL;
1593}
1594
1595/**
1596 * smack_file_ioctl - Smack check on ioctls
1597 * @file: the object
1598 * @cmd: what to do
1599 * @arg: unused
1600 *
1601 * Relies heavily on the correct use of the ioctl command conventions.
1602 *
1603 * Returns 0 if allowed, error code otherwise
1604 */
1605static int smack_file_ioctl(struct file *file, unsigned int cmd,
1606 unsigned long arg)
1607{
1608 int rc = 0;
1609 struct smk_audit_info ad;
1610 struct inode *inode = file_inode(file);
1611
1612 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1613 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1614
1615 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1616 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1617 rc = smk_bu_file(file, MAY_WRITE, rc);
1618 }
1619
1620 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1621 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1622 rc = smk_bu_file(file, MAY_READ, rc);
1623 }
1624
1625 return rc;
1626}
1627
1628/**
1629 * smack_file_lock - Smack check on file locking
1630 * @file: the object
1631 * @cmd: unused
1632 *
1633 * Returns 0 if current has lock access, error code otherwise
1634 */
1635static int smack_file_lock(struct file *file, unsigned int cmd)
1636{
1637 struct smk_audit_info ad;
1638 int rc;
1639 struct inode *inode = file_inode(file);
1640
1641 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1642 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1643 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1644 rc = smk_bu_file(file, MAY_LOCK, rc);
1645 return rc;
1646}
1647
1648/**
1649 * smack_file_fcntl - Smack check on fcntl
1650 * @file: the object
1651 * @cmd: what action to check
1652 * @arg: unused
1653 *
1654 * Generally these operations are harmless.
1655 * File locking operations present an obvious mechanism
1656 * for passing information, so they require write access.
1657 *
1658 * Returns 0 if current has access, error code otherwise
1659 */
1660static int smack_file_fcntl(struct file *file, unsigned int cmd,
1661 unsigned long arg)
1662{
1663 struct smk_audit_info ad;
1664 int rc = 0;
1665 struct inode *inode = file_inode(file);
1666
1667 switch (cmd) {
1668 case F_GETLK:
1669 break;
1670 case F_SETLK:
1671 case F_SETLKW:
1672 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1673 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1674 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1675 rc = smk_bu_file(file, MAY_LOCK, rc);
1676 break;
1677 case F_SETOWN:
1678 case F_SETSIG:
1679 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1680 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1681 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1682 rc = smk_bu_file(file, MAY_WRITE, rc);
1683 break;
1684 default:
1685 break;
1686 }
1687
1688 return rc;
1689}
1690
1691/**
1692 * smack_mmap_file :
1693 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1694 * if mapping anonymous memory.
1695 * @file contains the file structure for file to map (may be NULL).
1696 * @reqprot contains the protection requested by the application.
1697 * @prot contains the protection that will be applied by the kernel.
1698 * @flags contains the operational flags.
1699 * Return 0 if permission is granted.
1700 */
1701static int smack_mmap_file(struct file *file,
1702 unsigned long reqprot, unsigned long prot,
1703 unsigned long flags)
1704{
1705 struct smack_known *skp;
1706 struct smack_known *mkp;
1707 struct smack_rule *srp;
1708 struct task_smack *tsp;
1709 struct smack_known *okp;
1710 struct inode_smack *isp;
1711 int may;
1712 int mmay;
1713 int tmay;
1714 int rc;
1715
1716 if (file == NULL)
1717 return 0;
1718
1719 isp = file_inode(file)->i_security;
1720 if (isp->smk_mmap == NULL)
1721 return 0;
1722 mkp = isp->smk_mmap;
1723
1724 tsp = current_security();
1725 skp = smk_of_current();
1726 rc = 0;
1727
1728 rcu_read_lock();
1729 /*
1730 * For each Smack rule associated with the subject
1731 * label verify that the SMACK64MMAP also has access
1732 * to that rule's object label.
1733 */
1734 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1735 okp = srp->smk_object;
1736 /*
1737 * Matching labels always allows access.
1738 */
1739 if (mkp->smk_known == okp->smk_known)
1740 continue;
1741 /*
1742 * If there is a matching local rule take
1743 * that into account as well.
1744 */
1745 may = smk_access_entry(srp->smk_subject->smk_known,
1746 okp->smk_known,
1747 &tsp->smk_rules);
1748 if (may == -ENOENT)
1749 may = srp->smk_access;
1750 else
1751 may &= srp->smk_access;
1752 /*
1753 * If may is zero the SMACK64MMAP subject can't
1754 * possibly have less access.
1755 */
1756 if (may == 0)
1757 continue;
1758
1759 /*
1760 * Fetch the global list entry.
1761 * If there isn't one a SMACK64MMAP subject
1762 * can't have as much access as current.
1763 */
1764 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1765 &mkp->smk_rules);
1766 if (mmay == -ENOENT) {
1767 rc = -EACCES;
1768 break;
1769 }
1770 /*
1771 * If there is a local entry it modifies the
1772 * potential access, too.
1773 */
1774 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1775 &tsp->smk_rules);
1776 if (tmay != -ENOENT)
1777 mmay &= tmay;
1778
1779 /*
1780 * If there is any access available to current that is
1781 * not available to a SMACK64MMAP subject
1782 * deny access.
1783 */
1784 if ((may | mmay) != mmay) {
1785 rc = -EACCES;
1786 break;
1787 }
1788 }
1789
1790 rcu_read_unlock();
1791
1792 return rc;
1793}
1794
1795/**
1796 * smack_file_set_fowner - set the file security blob value
1797 * @file: object in question
1798 *
1799 */
1800static void smack_file_set_fowner(struct file *file)
1801{
1802 file->f_security = smk_of_current();
1803}
1804
1805/**
1806 * smack_file_send_sigiotask - Smack on sigio
1807 * @tsk: The target task
1808 * @fown: the object the signal come from
1809 * @signum: unused
1810 *
1811 * Allow a privileged task to get signals even if it shouldn't
1812 *
1813 * Returns 0 if a subject with the object's smack could
1814 * write to the task, an error code otherwise.
1815 */
1816static int smack_file_send_sigiotask(struct task_struct *tsk,
1817 struct fown_struct *fown, int signum)
1818{
1819 struct smack_known *skp;
1820 struct smack_known *tkp = smk_of_task(tsk->cred->security);
1821 struct file *file;
1822 int rc;
1823 struct smk_audit_info ad;
1824
1825 /*
1826 * struct fown_struct is never outside the context of a struct file
1827 */
1828 file = container_of(fown, struct file, f_owner);
1829
1830 /* we don't log here as rc can be overriden */
1831 skp = file->f_security;
1832 rc = smk_access(skp, tkp, MAY_WRITE, NULL);
1833 rc = smk_bu_note("sigiotask", skp, tkp, MAY_WRITE, rc);
1834 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1835 rc = 0;
1836
1837 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1838 smk_ad_setfield_u_tsk(&ad, tsk);
1839 smack_log(skp->smk_known, tkp->smk_known, MAY_WRITE, rc, &ad);
1840 return rc;
1841}
1842
1843/**
1844 * smack_file_receive - Smack file receive check
1845 * @file: the object
1846 *
1847 * Returns 0 if current has access, error code otherwise
1848 */
1849static int smack_file_receive(struct file *file)
1850{
1851 int rc;
1852 int may = 0;
1853 struct smk_audit_info ad;
1854 struct inode *inode = file_inode(file);
1855 struct socket *sock;
1856 struct task_smack *tsp;
1857 struct socket_smack *ssp;
1858
1859 if (unlikely(IS_PRIVATE(inode)))
1860 return 0;
1861
1862 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1863 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1864
1865 if (S_ISSOCK(inode->i_mode)) {
1866 sock = SOCKET_I(inode);
1867 ssp = sock->sk->sk_security;
1868 tsp = current_security();
1869 /*
1870 * If the receiving process can't write to the
1871 * passed socket or if the passed socket can't
1872 * write to the receiving process don't accept
1873 * the passed socket.
1874 */
1875 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
1876 rc = smk_bu_file(file, may, rc);
1877 if (rc < 0)
1878 return rc;
1879 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
1880 rc = smk_bu_file(file, may, rc);
1881 return rc;
1882 }
1883 /*
1884 * This code relies on bitmasks.
1885 */
1886 if (file->f_mode & FMODE_READ)
1887 may = MAY_READ;
1888 if (file->f_mode & FMODE_WRITE)
1889 may |= MAY_WRITE;
1890
1891 rc = smk_curacc(smk_of_inode(inode), may, &ad);
1892 rc = smk_bu_file(file, may, rc);
1893 return rc;
1894}
1895
1896/**
1897 * smack_file_open - Smack dentry open processing
1898 * @file: the object
1899 * @cred: task credential
1900 *
1901 * Set the security blob in the file structure.
1902 * Allow the open only if the task has read access. There are
1903 * many read operations (e.g. fstat) that you can do with an
1904 * fd even if you have the file open write-only.
1905 *
1906 * Returns 0
1907 */
1908static int smack_file_open(struct file *file, const struct cred *cred)
1909{
1910 struct task_smack *tsp = cred->security;
1911 struct inode *inode = file_inode(file);
1912 struct smk_audit_info ad;
1913 int rc;
1914
1915 if (smack_privileged(CAP_MAC_OVERRIDE))
1916 return 0;
1917
1918 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1919 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1920 rc = smk_access(tsp->smk_task, smk_of_inode(inode), MAY_READ, &ad);
1921 rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1922
1923 return rc;
1924}
1925
1926/*
1927 * Task hooks
1928 */
1929
1930/**
1931 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1932 * @new: the new credentials
1933 * @gfp: the atomicity of any memory allocations
1934 *
1935 * Prepare a blank set of credentials for modification. This must allocate all
1936 * the memory the LSM module might require such that cred_transfer() can
1937 * complete without error.
1938 */
1939static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1940{
1941 struct task_smack *tsp;
1942
1943 tsp = new_task_smack(NULL, NULL, gfp);
1944 if (tsp == NULL)
1945 return -ENOMEM;
1946
1947 cred->security = tsp;
1948
1949 return 0;
1950}
1951
1952
1953/**
1954 * smack_cred_free - "free" task-level security credentials
1955 * @cred: the credentials in question
1956 *
1957 */
1958static void smack_cred_free(struct cred *cred)
1959{
1960 struct task_smack *tsp = cred->security;
1961 struct smack_rule *rp;
1962 struct list_head *l;
1963 struct list_head *n;
1964
1965 if (tsp == NULL)
1966 return;
1967 cred->security = NULL;
1968
1969 smk_destroy_label_list(&tsp->smk_relabel);
1970
1971 list_for_each_safe(l, n, &tsp->smk_rules) {
1972 rp = list_entry(l, struct smack_rule, list);
1973 list_del(&rp->list);
1974 kfree(rp);
1975 }
1976 kfree(tsp);
1977}
1978
1979/**
1980 * smack_cred_prepare - prepare new set of credentials for modification
1981 * @new: the new credentials
1982 * @old: the original credentials
1983 * @gfp: the atomicity of any memory allocations
1984 *
1985 * Prepare a new set of credentials for modification.
1986 */
1987static int smack_cred_prepare(struct cred *new, const struct cred *old,
1988 gfp_t gfp)
1989{
1990 struct task_smack *old_tsp = old->security;
1991 struct task_smack *new_tsp;
1992 int rc;
1993
1994 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1995 if (new_tsp == NULL)
1996 return -ENOMEM;
1997
1998 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
1999 if (rc != 0)
2000 return rc;
2001
2002 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2003 gfp);
2004 if (rc != 0)
2005 return rc;
2006
2007 new->security = new_tsp;
2008 return 0;
2009}
2010
2011/**
2012 * smack_cred_transfer - Transfer the old credentials to the new credentials
2013 * @new: the new credentials
2014 * @old: the original credentials
2015 *
2016 * Fill in a set of blank credentials from another set of credentials.
2017 */
2018static void smack_cred_transfer(struct cred *new, const struct cred *old)
2019{
2020 struct task_smack *old_tsp = old->security;
2021 struct task_smack *new_tsp = new->security;
2022
2023 new_tsp->smk_task = old_tsp->smk_task;
2024 new_tsp->smk_forked = old_tsp->smk_task;
2025 mutex_init(&new_tsp->smk_rules_lock);
2026 INIT_LIST_HEAD(&new_tsp->smk_rules);
2027
2028
2029 /* cbs copy rule list */
2030}
2031
2032/**
2033 * smack_kernel_act_as - Set the subjective context in a set of credentials
2034 * @new: points to the set of credentials to be modified.
2035 * @secid: specifies the security ID to be set
2036 *
2037 * Set the security data for a kernel service.
2038 */
2039static int smack_kernel_act_as(struct cred *new, u32 secid)
2040{
2041 struct task_smack *new_tsp = new->security;
2042 struct smack_known *skp = smack_from_secid(secid);
2043
2044 if (skp == NULL)
2045 return -EINVAL;
2046
2047 new_tsp->smk_task = skp;
2048 return 0;
2049}
2050
2051/**
2052 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2053 * @new: points to the set of credentials to be modified
2054 * @inode: points to the inode to use as a reference
2055 *
2056 * Set the file creation context in a set of credentials to the same
2057 * as the objective context of the specified inode
2058 */
2059static int smack_kernel_create_files_as(struct cred *new,
2060 struct inode *inode)
2061{
2062 struct inode_smack *isp = inode->i_security;
2063 struct task_smack *tsp = new->security;
2064
2065 tsp->smk_forked = isp->smk_inode;
2066 tsp->smk_task = tsp->smk_forked;
2067 return 0;
2068}
2069
2070/**
2071 * smk_curacc_on_task - helper to log task related access
2072 * @p: the task object
2073 * @access: the access requested
2074 * @caller: name of the calling function for audit
2075 *
2076 * Return 0 if access is permitted
2077 */
2078static int smk_curacc_on_task(struct task_struct *p, int access,
2079 const char *caller)
2080{
2081 struct smk_audit_info ad;
2082 struct smack_known *skp = smk_of_task_struct(p);
2083 int rc;
2084
2085 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2086 smk_ad_setfield_u_tsk(&ad, p);
2087 rc = smk_curacc(skp, access, &ad);
2088 rc = smk_bu_task(p, access, rc);
2089 return rc;
2090}
2091
2092/**
2093 * smack_task_setpgid - Smack check on setting pgid
2094 * @p: the task object
2095 * @pgid: unused
2096 *
2097 * Return 0 if write access is permitted
2098 */
2099static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2100{
2101 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2102}
2103
2104/**
2105 * smack_task_getpgid - Smack access check for getpgid
2106 * @p: the object task
2107 *
2108 * Returns 0 if current can read the object task, error code otherwise
2109 */
2110static int smack_task_getpgid(struct task_struct *p)
2111{
2112 return smk_curacc_on_task(p, MAY_READ, __func__);
2113}
2114
2115/**
2116 * smack_task_getsid - Smack access check for getsid
2117 * @p: the object task
2118 *
2119 * Returns 0 if current can read the object task, error code otherwise
2120 */
2121static int smack_task_getsid(struct task_struct *p)
2122{
2123 return smk_curacc_on_task(p, MAY_READ, __func__);
2124}
2125
2126/**
2127 * smack_task_getsecid - get the secid of the task
2128 * @p: the object task
2129 * @secid: where to put the result
2130 *
2131 * Sets the secid to contain a u32 version of the smack label.
2132 */
2133static void smack_task_getsecid(struct task_struct *p, u32 *secid)
2134{
2135 struct smack_known *skp = smk_of_task_struct(p);
2136
2137 *secid = skp->smk_secid;
2138}
2139
2140/**
2141 * smack_task_setnice - Smack check on setting nice
2142 * @p: the task object
2143 * @nice: unused
2144 *
2145 * Return 0 if write access is permitted
2146 */
2147static int smack_task_setnice(struct task_struct *p, int nice)
2148{
2149 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2150}
2151
2152/**
2153 * smack_task_setioprio - Smack check on setting ioprio
2154 * @p: the task object
2155 * @ioprio: unused
2156 *
2157 * Return 0 if write access is permitted
2158 */
2159static int smack_task_setioprio(struct task_struct *p, int ioprio)
2160{
2161 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2162}
2163
2164/**
2165 * smack_task_getioprio - Smack check on reading ioprio
2166 * @p: the task object
2167 *
2168 * Return 0 if read access is permitted
2169 */
2170static int smack_task_getioprio(struct task_struct *p)
2171{
2172 return smk_curacc_on_task(p, MAY_READ, __func__);
2173}
2174
2175/**
2176 * smack_task_setscheduler - Smack check on setting scheduler
2177 * @p: the task object
2178 * @policy: unused
2179 * @lp: unused
2180 *
2181 * Return 0 if read access is permitted
2182 */
2183static int smack_task_setscheduler(struct task_struct *p)
2184{
2185 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2186}
2187
2188/**
2189 * smack_task_getscheduler - Smack check on reading scheduler
2190 * @p: the task object
2191 *
2192 * Return 0 if read access is permitted
2193 */
2194static int smack_task_getscheduler(struct task_struct *p)
2195{
2196 return smk_curacc_on_task(p, MAY_READ, __func__);
2197}
2198
2199/**
2200 * smack_task_movememory - Smack check on moving memory
2201 * @p: the task object
2202 *
2203 * Return 0 if write access is permitted
2204 */
2205static int smack_task_movememory(struct task_struct *p)
2206{
2207 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2208}
2209
2210/**
2211 * smack_task_kill - Smack check on signal delivery
2212 * @p: the task object
2213 * @info: unused
2214 * @sig: unused
2215 * @secid: identifies the smack to use in lieu of current's
2216 *
2217 * Return 0 if write access is permitted
2218 *
2219 * The secid behavior is an artifact of an SELinux hack
2220 * in the USB code. Someday it may go away.
2221 */
2222static int smack_task_kill(struct task_struct *p, struct siginfo *info,
2223 int sig, u32 secid)
2224{
2225 struct smk_audit_info ad;
2226 struct smack_known *skp;
2227 struct smack_known *tkp = smk_of_task_struct(p);
2228 int rc;
2229
2230 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2231 smk_ad_setfield_u_tsk(&ad, p);
2232 /*
2233 * Sending a signal requires that the sender
2234 * can write the receiver.
2235 */
2236 if (secid == 0) {
2237 rc = smk_curacc(tkp, MAY_WRITE, &ad);
2238 rc = smk_bu_task(p, MAY_WRITE, rc);
2239 return rc;
2240 }
2241 /*
2242 * If the secid isn't 0 we're dealing with some USB IO
2243 * specific behavior. This is not clean. For one thing
2244 * we can't take privilege into account.
2245 */
2246 skp = smack_from_secid(secid);
2247 rc = smk_access(skp, tkp, MAY_WRITE, &ad);
2248 rc = smk_bu_note("USB signal", skp, tkp, MAY_WRITE, rc);
2249 return rc;
2250}
2251
2252/**
2253 * smack_task_wait - Smack access check for waiting
2254 * @p: task to wait for
2255 *
2256 * Returns 0
2257 */
2258static int smack_task_wait(struct task_struct *p)
2259{
2260 /*
2261 * Allow the operation to succeed.
2262 * Zombies are bad.
2263 * In userless environments (e.g. phones) programs
2264 * get marked with SMACK64EXEC and even if the parent
2265 * and child shouldn't be talking the parent still
2266 * may expect to know when the child exits.
2267 */
2268 return 0;
2269}
2270
2271/**
2272 * smack_task_to_inode - copy task smack into the inode blob
2273 * @p: task to copy from
2274 * @inode: inode to copy to
2275 *
2276 * Sets the smack pointer in the inode security blob
2277 */
2278static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2279{
2280 struct inode_smack *isp = inode->i_security;
2281 struct smack_known *skp = smk_of_task_struct(p);
2282
2283 isp->smk_inode = skp;
2284}
2285
2286/*
2287 * Socket hooks.
2288 */
2289
2290/**
2291 * smack_sk_alloc_security - Allocate a socket blob
2292 * @sk: the socket
2293 * @family: unused
2294 * @gfp_flags: memory allocation flags
2295 *
2296 * Assign Smack pointers to current
2297 *
2298 * Returns 0 on success, -ENOMEM is there's no memory
2299 */
2300static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2301{
2302 struct smack_known *skp = smk_of_current();
2303 struct socket_smack *ssp;
2304
2305 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
2306 if (ssp == NULL)
2307 return -ENOMEM;
2308
2309 ssp->smk_in = skp;
2310 ssp->smk_out = skp;
2311 ssp->smk_packet = NULL;
2312
2313 sk->sk_security = ssp;
2314
2315 return 0;
2316}
2317
2318/**
2319 * smack_sk_free_security - Free a socket blob
2320 * @sk: the socket
2321 *
2322 * Clears the blob pointer
2323 */
2324static void smack_sk_free_security(struct sock *sk)
2325{
2326 kfree(sk->sk_security);
2327}
2328
2329/**
2330* smack_ipv4host_label - check host based restrictions
2331* @sip: the object end
2332*
2333* looks for host based access restrictions
2334*
2335* This version will only be appropriate for really small sets of single label
2336* hosts. The caller is responsible for ensuring that the RCU read lock is
2337* taken before calling this function.
2338*
2339* Returns the label of the far end or NULL if it's not special.
2340*/
2341static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2342{
2343 struct smk_net4addr *snp;
2344 struct in_addr *siap = &sip->sin_addr;
2345
2346 if (siap->s_addr == 0)
2347 return NULL;
2348
2349 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2350 /*
2351 * we break after finding the first match because
2352 * the list is sorted from longest to shortest mask
2353 * so we have found the most specific match
2354 */
2355 if (snp->smk_host.s_addr ==
2356 (siap->s_addr & snp->smk_mask.s_addr))
2357 return snp->smk_label;
2358
2359 return NULL;
2360}
2361
2362#if IS_ENABLED(CONFIG_IPV6)
2363/*
2364 * smk_ipv6_localhost - Check for local ipv6 host address
2365 * @sip: the address
2366 *
2367 * Returns boolean true if this is the localhost address
2368 */
2369static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2370{
2371 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2372 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2373
2374 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2375 ntohs(be16p[7]) == 1)
2376 return true;
2377 return false;
2378}
2379
2380/**
2381* smack_ipv6host_label - check host based restrictions
2382* @sip: the object end
2383*
2384* looks for host based access restrictions
2385*
2386* This version will only be appropriate for really small sets of single label
2387* hosts. The caller is responsible for ensuring that the RCU read lock is
2388* taken before calling this function.
2389*
2390* Returns the label of the far end or NULL if it's not special.
2391*/
2392static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2393{
2394 struct smk_net6addr *snp;
2395 struct in6_addr *sap = &sip->sin6_addr;
2396 int i;
2397 int found = 0;
2398
2399 /*
2400 * It's local. Don't look for a host label.
2401 */
2402 if (smk_ipv6_localhost(sip))
2403 return NULL;
2404
2405 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2406 /*
2407 * we break after finding the first match because
2408 * the list is sorted from longest to shortest mask
2409 * so we have found the most specific match
2410 */
2411 for (found = 1, i = 0; i < 8; i++) {
2412 /*
2413 * If the label is NULL the entry has
2414 * been renounced. Ignore it.
2415 */
2416 if (snp->smk_label == NULL)
2417 continue;
2418 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2419 snp->smk_host.s6_addr16[i]) {
2420 found = 0;
2421 break;
2422 }
2423 }
2424 if (found)
2425 return snp->smk_label;
2426 }
2427
2428 return NULL;
2429}
2430#endif /* CONFIG_IPV6 */
2431
2432/**
2433 * smack_netlabel - Set the secattr on a socket
2434 * @sk: the socket
2435 * @labeled: socket label scheme
2436 *
2437 * Convert the outbound smack value (smk_out) to a
2438 * secattr and attach it to the socket.
2439 *
2440 * Returns 0 on success or an error code
2441 */
2442static int smack_netlabel(struct sock *sk, int labeled)
2443{
2444 struct smack_known *skp;
2445 struct socket_smack *ssp = sk->sk_security;
2446 int rc = 0;
2447
2448 /*
2449 * Usually the netlabel code will handle changing the
2450 * packet labeling based on the label.
2451 * The case of a single label host is different, because
2452 * a single label host should never get a labeled packet
2453 * even though the label is usually associated with a packet
2454 * label.
2455 */
2456 local_bh_disable();
2457 bh_lock_sock_nested(sk);
2458
2459 if (ssp->smk_out == smack_net_ambient ||
2460 labeled == SMACK_UNLABELED_SOCKET)
2461 netlbl_sock_delattr(sk);
2462 else {
2463 skp = ssp->smk_out;
2464 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2465 }
2466
2467 bh_unlock_sock(sk);
2468 local_bh_enable();
2469
2470 return rc;
2471}
2472
2473/**
2474 * smack_netlbel_send - Set the secattr on a socket and perform access checks
2475 * @sk: the socket
2476 * @sap: the destination address
2477 *
2478 * Set the correct secattr for the given socket based on the destination
2479 * address and perform any outbound access checks needed.
2480 *
2481 * Returns 0 on success or an error code.
2482 *
2483 */
2484static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
2485{
2486 struct smack_known *skp;
2487 int rc;
2488 int sk_lbl;
2489 struct smack_known *hkp;
2490 struct socket_smack *ssp = sk->sk_security;
2491 struct smk_audit_info ad;
2492
2493 rcu_read_lock();
2494 hkp = smack_ipv4host_label(sap);
2495 if (hkp != NULL) {
2496#ifdef CONFIG_AUDIT
2497 struct lsm_network_audit net;
2498
2499 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2500 ad.a.u.net->family = sap->sin_family;
2501 ad.a.u.net->dport = sap->sin_port;
2502 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2503#endif
2504 sk_lbl = SMACK_UNLABELED_SOCKET;
2505 skp = ssp->smk_out;
2506 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2507 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2508 } else {
2509 sk_lbl = SMACK_CIPSO_SOCKET;
2510 rc = 0;
2511 }
2512 rcu_read_unlock();
2513 if (rc != 0)
2514 return rc;
2515
2516 return smack_netlabel(sk, sk_lbl);
2517}
2518
2519#if IS_ENABLED(CONFIG_IPV6)
2520/**
2521 * smk_ipv6_check - check Smack access
2522 * @subject: subject Smack label
2523 * @object: object Smack label
2524 * @address: address
2525 * @act: the action being taken
2526 *
2527 * Check an IPv6 access
2528 */
2529static int smk_ipv6_check(struct smack_known *subject,
2530 struct smack_known *object,
2531 struct sockaddr_in6 *address, int act)
2532{
2533#ifdef CONFIG_AUDIT
2534 struct lsm_network_audit net;
2535#endif
2536 struct smk_audit_info ad;
2537 int rc;
2538
2539#ifdef CONFIG_AUDIT
2540 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2541 ad.a.u.net->family = PF_INET6;
2542 ad.a.u.net->dport = ntohs(address->sin6_port);
2543 if (act == SMK_RECEIVING)
2544 ad.a.u.net->v6info.saddr = address->sin6_addr;
2545 else
2546 ad.a.u.net->v6info.daddr = address->sin6_addr;
2547#endif
2548 rc = smk_access(subject, object, MAY_WRITE, &ad);
2549 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2550 return rc;
2551}
2552#endif /* CONFIG_IPV6 */
2553
2554#ifdef SMACK_IPV6_PORT_LABELING
2555/**
2556 * smk_ipv6_port_label - Smack port access table management
2557 * @sock: socket
2558 * @address: address
2559 *
2560 * Create or update the port list entry
2561 */
2562static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2563{
2564 struct sock *sk = sock->sk;
2565 struct sockaddr_in6 *addr6;
2566 struct socket_smack *ssp = sock->sk->sk_security;
2567 struct smk_port_label *spp;
2568 unsigned short port = 0;
2569
2570 if (address == NULL) {
2571 /*
2572 * This operation is changing the Smack information
2573 * on the bound socket. Take the changes to the port
2574 * as well.
2575 */
2576 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2577 if (sk != spp->smk_sock)
2578 continue;
2579 spp->smk_in = ssp->smk_in;
2580 spp->smk_out = ssp->smk_out;
2581 return;
2582 }
2583 /*
2584 * A NULL address is only used for updating existing
2585 * bound entries. If there isn't one, it's OK.
2586 */
2587 return;
2588 }
2589
2590 addr6 = (struct sockaddr_in6 *)address;
2591 port = ntohs(addr6->sin6_port);
2592 /*
2593 * This is a special case that is safely ignored.
2594 */
2595 if (port == 0)
2596 return;
2597
2598 /*
2599 * Look for an existing port list entry.
2600 * This is an indication that a port is getting reused.
2601 */
2602 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2603 if (spp->smk_port != port)
2604 continue;
2605 spp->smk_port = port;
2606 spp->smk_sock = sk;
2607 spp->smk_in = ssp->smk_in;
2608 spp->smk_out = ssp->smk_out;
2609 return;
2610 }
2611
2612 /*
2613 * A new port entry is required.
2614 */
2615 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2616 if (spp == NULL)
2617 return;
2618
2619 spp->smk_port = port;
2620 spp->smk_sock = sk;
2621 spp->smk_in = ssp->smk_in;
2622 spp->smk_out = ssp->smk_out;
2623
2624 list_add(&spp->list, &smk_ipv6_port_list);
2625 return;
2626}
2627
2628/**
2629 * smk_ipv6_port_check - check Smack port access
2630 * @sock: socket
2631 * @address: address
2632 *
2633 * Create or update the port list entry
2634 */
2635static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2636 int act)
2637{
2638 struct smk_port_label *spp;
2639 struct socket_smack *ssp = sk->sk_security;
2640 struct smack_known *skp = NULL;
2641 unsigned short port;
2642 struct smack_known *object;
2643
2644 if (act == SMK_RECEIVING) {
2645 skp = smack_ipv6host_label(address);
2646 object = ssp->smk_in;
2647 } else {
2648 skp = ssp->smk_out;
2649 object = smack_ipv6host_label(address);
2650 }
2651
2652 /*
2653 * The other end is a single label host.
2654 */
2655 if (skp != NULL && object != NULL)
2656 return smk_ipv6_check(skp, object, address, act);
2657 if (skp == NULL)
2658 skp = smack_net_ambient;
2659 if (object == NULL)
2660 object = smack_net_ambient;
2661
2662 /*
2663 * It's remote, so port lookup does no good.
2664 */
2665 if (!smk_ipv6_localhost(address))
2666 return smk_ipv6_check(skp, object, address, act);
2667
2668 /*
2669 * It's local so the send check has to have passed.
2670 */
2671 if (act == SMK_RECEIVING)
2672 return 0;
2673
2674 port = ntohs(address->sin6_port);
2675 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2676 if (spp->smk_port != port)
2677 continue;
2678 object = spp->smk_in;
2679 if (act == SMK_CONNECTING)
2680 ssp->smk_packet = spp->smk_out;
2681 break;
2682 }
2683
2684 return smk_ipv6_check(skp, object, address, act);
2685}
2686#endif /* SMACK_IPV6_PORT_LABELING */
2687
2688/**
2689 * smack_inode_setsecurity - set smack xattrs
2690 * @inode: the object
2691 * @name: attribute name
2692 * @value: attribute value
2693 * @size: size of the attribute
2694 * @flags: unused
2695 *
2696 * Sets the named attribute in the appropriate blob
2697 *
2698 * Returns 0 on success, or an error code
2699 */
2700static int smack_inode_setsecurity(struct inode *inode, const char *name,
2701 const void *value, size_t size, int flags)
2702{
2703 struct smack_known *skp;
2704 struct inode_smack *nsp = inode->i_security;
2705 struct socket_smack *ssp;
2706 struct socket *sock;
2707 int rc = 0;
2708
2709 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2710 return -EINVAL;
2711
2712 skp = smk_import_entry(value, size);
2713 if (IS_ERR(skp))
2714 return PTR_ERR(skp);
2715
2716 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2717 nsp->smk_inode = skp;
2718 nsp->smk_flags |= SMK_INODE_INSTANT;
2719 return 0;
2720 }
2721 /*
2722 * The rest of the Smack xattrs are only on sockets.
2723 */
2724 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2725 return -EOPNOTSUPP;
2726
2727 sock = SOCKET_I(inode);
2728 if (sock == NULL || sock->sk == NULL)
2729 return -EOPNOTSUPP;
2730
2731 ssp = sock->sk->sk_security;
2732
2733 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2734 ssp->smk_in = skp;
2735 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2736 ssp->smk_out = skp;
2737 if (sock->sk->sk_family == PF_INET) {
2738 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2739 if (rc != 0)
2740 printk(KERN_WARNING
2741 "Smack: \"%s\" netlbl error %d.\n",
2742 __func__, -rc);
2743 }
2744 } else
2745 return -EOPNOTSUPP;
2746
2747#ifdef SMACK_IPV6_PORT_LABELING
2748 if (sock->sk->sk_family == PF_INET6)
2749 smk_ipv6_port_label(sock, NULL);
2750#endif
2751
2752 return 0;
2753}
2754
2755/**
2756 * smack_socket_post_create - finish socket setup
2757 * @sock: the socket
2758 * @family: protocol family
2759 * @type: unused
2760 * @protocol: unused
2761 * @kern: unused
2762 *
2763 * Sets the netlabel information on the socket
2764 *
2765 * Returns 0 on success, and error code otherwise
2766 */
2767static int smack_socket_post_create(struct socket *sock, int family,
2768 int type, int protocol, int kern)
2769{
2770 struct socket_smack *ssp;
2771
2772 if (sock->sk == NULL)
2773 return 0;
2774
2775 /*
2776 * Sockets created by kernel threads receive web label.
2777 */
2778 if (unlikely(current->flags & PF_KTHREAD)) {
2779 ssp = sock->sk->sk_security;
2780 ssp->smk_in = &smack_known_web;
2781 ssp->smk_out = &smack_known_web;
2782 }
2783
2784 if (family != PF_INET)
2785 return 0;
2786 /*
2787 * Set the outbound netlbl.
2788 */
2789 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2790}
2791
2792#ifdef SMACK_IPV6_PORT_LABELING
2793/**
2794 * smack_socket_bind - record port binding information.
2795 * @sock: the socket
2796 * @address: the port address
2797 * @addrlen: size of the address
2798 *
2799 * Records the label bound to a port.
2800 *
2801 * Returns 0
2802 */
2803static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
2804 int addrlen)
2805{
2806 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
2807 smk_ipv6_port_label(sock, address);
2808 return 0;
2809}
2810#endif /* SMACK_IPV6_PORT_LABELING */
2811
2812/**
2813 * smack_socket_connect - connect access check
2814 * @sock: the socket
2815 * @sap: the other end
2816 * @addrlen: size of sap
2817 *
2818 * Verifies that a connection may be possible
2819 *
2820 * Returns 0 on success, and error code otherwise
2821 */
2822static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2823 int addrlen)
2824{
2825 int rc = 0;
2826#if IS_ENABLED(CONFIG_IPV6)
2827 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
2828#endif
2829#ifdef SMACK_IPV6_SECMARK_LABELING
2830 struct smack_known *rsp;
2831 struct socket_smack *ssp = sock->sk->sk_security;
2832#endif
2833
2834 if (sock->sk == NULL)
2835 return 0;
2836
2837 switch (sock->sk->sk_family) {
2838 case PF_INET:
2839 if (addrlen < sizeof(struct sockaddr_in))
2840 return -EINVAL;
2841 rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2842 break;
2843 case PF_INET6:
2844 if (addrlen < sizeof(struct sockaddr_in6))
2845 return -EINVAL;
2846#ifdef SMACK_IPV6_SECMARK_LABELING
2847 rsp = smack_ipv6host_label(sip);
2848 if (rsp != NULL)
2849 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
2850 SMK_CONNECTING);
2851#endif
2852#ifdef SMACK_IPV6_PORT_LABELING
2853 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
2854#endif
2855 break;
2856 }
2857 return rc;
2858}
2859
2860/**
2861 * smack_flags_to_may - convert S_ to MAY_ values
2862 * @flags: the S_ value
2863 *
2864 * Returns the equivalent MAY_ value
2865 */
2866static int smack_flags_to_may(int flags)
2867{
2868 int may = 0;
2869
2870 if (flags & S_IRUGO)
2871 may |= MAY_READ;
2872 if (flags & S_IWUGO)
2873 may |= MAY_WRITE;
2874 if (flags & S_IXUGO)
2875 may |= MAY_EXEC;
2876
2877 return may;
2878}
2879
2880/**
2881 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2882 * @msg: the object
2883 *
2884 * Returns 0
2885 */
2886static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2887{
2888 struct smack_known *skp = smk_of_current();
2889
2890 msg->security = skp;
2891 return 0;
2892}
2893
2894/**
2895 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2896 * @msg: the object
2897 *
2898 * Clears the blob pointer
2899 */
2900static void smack_msg_msg_free_security(struct msg_msg *msg)
2901{
2902 msg->security = NULL;
2903}
2904
2905/**
2906 * smack_of_shm - the smack pointer for the shm
2907 * @shp: the object
2908 *
2909 * Returns a pointer to the smack value
2910 */
2911static struct smack_known *smack_of_shm(struct shmid_kernel *shp)
2912{
2913 return (struct smack_known *)shp->shm_perm.security;
2914}
2915
2916/**
2917 * smack_shm_alloc_security - Set the security blob for shm
2918 * @shp: the object
2919 *
2920 * Returns 0
2921 */
2922static int smack_shm_alloc_security(struct shmid_kernel *shp)
2923{
2924 struct kern_ipc_perm *isp = &shp->shm_perm;
2925 struct smack_known *skp = smk_of_current();
2926
2927 isp->security = skp;
2928 return 0;
2929}
2930
2931/**
2932 * smack_shm_free_security - Clear the security blob for shm
2933 * @shp: the object
2934 *
2935 * Clears the blob pointer
2936 */
2937static void smack_shm_free_security(struct shmid_kernel *shp)
2938{
2939 struct kern_ipc_perm *isp = &shp->shm_perm;
2940
2941 isp->security = NULL;
2942}
2943
2944/**
2945 * smk_curacc_shm : check if current has access on shm
2946 * @shp : the object
2947 * @access : access requested
2948 *
2949 * Returns 0 if current has the requested access, error code otherwise
2950 */
2951static int smk_curacc_shm(struct shmid_kernel *shp, int access)
2952{
2953 struct smack_known *ssp = smack_of_shm(shp);
2954 struct smk_audit_info ad;
2955 int rc;
2956
2957#ifdef CONFIG_AUDIT
2958 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2959 ad.a.u.ipc_id = shp->shm_perm.id;
2960#endif
2961 rc = smk_curacc(ssp, access, &ad);
2962 rc = smk_bu_current("shm", ssp, access, rc);
2963 return rc;
2964}
2965
2966/**
2967 * smack_shm_associate - Smack access check for shm
2968 * @shp: the object
2969 * @shmflg: access requested
2970 *
2971 * Returns 0 if current has the requested access, error code otherwise
2972 */
2973static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
2974{
2975 int may;
2976
2977 may = smack_flags_to_may(shmflg);
2978 return smk_curacc_shm(shp, may);
2979}
2980
2981/**
2982 * smack_shm_shmctl - Smack access check for shm
2983 * @shp: the object
2984 * @cmd: what it wants to do
2985 *
2986 * Returns 0 if current has the requested access, error code otherwise
2987 */
2988static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
2989{
2990 int may;
2991
2992 switch (cmd) {
2993 case IPC_STAT:
2994 case SHM_STAT:
2995 may = MAY_READ;
2996 break;
2997 case IPC_SET:
2998 case SHM_LOCK:
2999 case SHM_UNLOCK:
3000 case IPC_RMID:
3001 may = MAY_READWRITE;
3002 break;
3003 case IPC_INFO:
3004 case SHM_INFO:
3005 /*
3006 * System level information.
3007 */
3008 return 0;
3009 default:
3010 return -EINVAL;
3011 }
3012 return smk_curacc_shm(shp, may);
3013}
3014
3015/**
3016 * smack_shm_shmat - Smack access for shmat
3017 * @shp: the object
3018 * @shmaddr: unused
3019 * @shmflg: access requested
3020 *
3021 * Returns 0 if current has the requested access, error code otherwise
3022 */
3023static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
3024 int shmflg)
3025{
3026 int may;
3027
3028 may = smack_flags_to_may(shmflg);
3029 return smk_curacc_shm(shp, may);
3030}
3031
3032/**
3033 * smack_of_sem - the smack pointer for the sem
3034 * @sma: the object
3035 *
3036 * Returns a pointer to the smack value
3037 */
3038static struct smack_known *smack_of_sem(struct sem_array *sma)
3039{
3040 return (struct smack_known *)sma->sem_perm.security;
3041}
3042
3043/**
3044 * smack_sem_alloc_security - Set the security blob for sem
3045 * @sma: the object
3046 *
3047 * Returns 0
3048 */
3049static int smack_sem_alloc_security(struct sem_array *sma)
3050{
3051 struct kern_ipc_perm *isp = &sma->sem_perm;
3052 struct smack_known *skp = smk_of_current();
3053
3054 isp->security = skp;
3055 return 0;
3056}
3057
3058/**
3059 * smack_sem_free_security - Clear the security blob for sem
3060 * @sma: the object
3061 *
3062 * Clears the blob pointer
3063 */
3064static void smack_sem_free_security(struct sem_array *sma)
3065{
3066 struct kern_ipc_perm *isp = &sma->sem_perm;
3067
3068 isp->security = NULL;
3069}
3070
3071/**
3072 * smk_curacc_sem : check if current has access on sem
3073 * @sma : the object
3074 * @access : access requested
3075 *
3076 * Returns 0 if current has the requested access, error code otherwise
3077 */
3078static int smk_curacc_sem(struct sem_array *sma, int access)
3079{
3080 struct smack_known *ssp = smack_of_sem(sma);
3081 struct smk_audit_info ad;
3082 int rc;
3083
3084#ifdef CONFIG_AUDIT
3085 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3086 ad.a.u.ipc_id = sma->sem_perm.id;
3087#endif
3088 rc = smk_curacc(ssp, access, &ad);
3089 rc = smk_bu_current("sem", ssp, access, rc);
3090 return rc;
3091}
3092
3093/**
3094 * smack_sem_associate - Smack access check for sem
3095 * @sma: the object
3096 * @semflg: access requested
3097 *
3098 * Returns 0 if current has the requested access, error code otherwise
3099 */
3100static int smack_sem_associate(struct sem_array *sma, int semflg)
3101{
3102 int may;
3103
3104 may = smack_flags_to_may(semflg);
3105 return smk_curacc_sem(sma, may);
3106}
3107
3108/**
3109 * smack_sem_shmctl - Smack access check for sem
3110 * @sma: the object
3111 * @cmd: what it wants to do
3112 *
3113 * Returns 0 if current has the requested access, error code otherwise
3114 */
3115static int smack_sem_semctl(struct sem_array *sma, int cmd)
3116{
3117 int may;
3118
3119 switch (cmd) {
3120 case GETPID:
3121 case GETNCNT:
3122 case GETZCNT:
3123 case GETVAL:
3124 case GETALL:
3125 case IPC_STAT:
3126 case SEM_STAT:
3127 may = MAY_READ;
3128 break;
3129 case SETVAL:
3130 case SETALL:
3131 case IPC_RMID:
3132 case IPC_SET:
3133 may = MAY_READWRITE;
3134 break;
3135 case IPC_INFO:
3136 case SEM_INFO:
3137 /*
3138 * System level information
3139 */
3140 return 0;
3141 default:
3142 return -EINVAL;
3143 }
3144
3145 return smk_curacc_sem(sma, may);
3146}
3147
3148/**
3149 * smack_sem_semop - Smack checks of semaphore operations
3150 * @sma: the object
3151 * @sops: unused
3152 * @nsops: unused
3153 * @alter: unused
3154 *
3155 * Treated as read and write in all cases.
3156 *
3157 * Returns 0 if access is allowed, error code otherwise
3158 */
3159static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
3160 unsigned nsops, int alter)
3161{
3162 return smk_curacc_sem(sma, MAY_READWRITE);
3163}
3164
3165/**
3166 * smack_msg_alloc_security - Set the security blob for msg
3167 * @msq: the object
3168 *
3169 * Returns 0
3170 */
3171static int smack_msg_queue_alloc_security(struct msg_queue *msq)
3172{
3173 struct kern_ipc_perm *kisp = &msq->q_perm;
3174 struct smack_known *skp = smk_of_current();
3175
3176 kisp->security = skp;
3177 return 0;
3178}
3179
3180/**
3181 * smack_msg_free_security - Clear the security blob for msg
3182 * @msq: the object
3183 *
3184 * Clears the blob pointer
3185 */
3186static void smack_msg_queue_free_security(struct msg_queue *msq)
3187{
3188 struct kern_ipc_perm *kisp = &msq->q_perm;
3189
3190 kisp->security = NULL;
3191}
3192
3193/**
3194 * smack_of_msq - the smack pointer for the msq
3195 * @msq: the object
3196 *
3197 * Returns a pointer to the smack label entry
3198 */
3199static struct smack_known *smack_of_msq(struct msg_queue *msq)
3200{
3201 return (struct smack_known *)msq->q_perm.security;
3202}
3203
3204/**
3205 * smk_curacc_msq : helper to check if current has access on msq
3206 * @msq : the msq
3207 * @access : access requested
3208 *
3209 * return 0 if current has access, error otherwise
3210 */
3211static int smk_curacc_msq(struct msg_queue *msq, int access)
3212{
3213 struct smack_known *msp = smack_of_msq(msq);
3214 struct smk_audit_info ad;
3215 int rc;
3216
3217#ifdef CONFIG_AUDIT
3218 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3219 ad.a.u.ipc_id = msq->q_perm.id;
3220#endif
3221 rc = smk_curacc(msp, access, &ad);
3222 rc = smk_bu_current("msq", msp, access, rc);
3223 return rc;
3224}
3225
3226/**
3227 * smack_msg_queue_associate - Smack access check for msg_queue
3228 * @msq: the object
3229 * @msqflg: access requested
3230 *
3231 * Returns 0 if current has the requested access, error code otherwise
3232 */
3233static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
3234{
3235 int may;
3236
3237 may = smack_flags_to_may(msqflg);
3238 return smk_curacc_msq(msq, may);
3239}
3240
3241/**
3242 * smack_msg_queue_msgctl - Smack access check for msg_queue
3243 * @msq: the object
3244 * @cmd: what it wants to do
3245 *
3246 * Returns 0 if current has the requested access, error code otherwise
3247 */
3248static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3249{
3250 int may;
3251
3252 switch (cmd) {
3253 case IPC_STAT:
3254 case MSG_STAT:
3255 may = MAY_READ;
3256 break;
3257 case IPC_SET:
3258 case IPC_RMID:
3259 may = MAY_READWRITE;
3260 break;
3261 case IPC_INFO:
3262 case MSG_INFO:
3263 /*
3264 * System level information
3265 */
3266 return 0;
3267 default:
3268 return -EINVAL;
3269 }
3270
3271 return smk_curacc_msq(msq, may);
3272}
3273
3274/**
3275 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3276 * @msq: the object
3277 * @msg: unused
3278 * @msqflg: access requested
3279 *
3280 * Returns 0 if current has the requested access, error code otherwise
3281 */
3282static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
3283 int msqflg)
3284{
3285 int may;
3286
3287 may = smack_flags_to_may(msqflg);
3288 return smk_curacc_msq(msq, may);
3289}
3290
3291/**
3292 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3293 * @msq: the object
3294 * @msg: unused
3295 * @target: unused
3296 * @type: unused
3297 * @mode: unused
3298 *
3299 * Returns 0 if current has read and write access, error code otherwise
3300 */
3301static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3302 struct task_struct *target, long type, int mode)
3303{
3304 return smk_curacc_msq(msq, MAY_READWRITE);
3305}
3306
3307/**
3308 * smack_ipc_permission - Smack access for ipc_permission()
3309 * @ipp: the object permissions
3310 * @flag: access requested
3311 *
3312 * Returns 0 if current has read and write access, error code otherwise
3313 */
3314static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3315{
3316 struct smack_known *iskp = ipp->security;
3317 int may = smack_flags_to_may(flag);
3318 struct smk_audit_info ad;
3319 int rc;
3320
3321#ifdef CONFIG_AUDIT
3322 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3323 ad.a.u.ipc_id = ipp->id;
3324#endif
3325 rc = smk_curacc(iskp, may, &ad);
3326 rc = smk_bu_current("svipc", iskp, may, rc);
3327 return rc;
3328}
3329
3330/**
3331 * smack_ipc_getsecid - Extract smack security id
3332 * @ipp: the object permissions
3333 * @secid: where result will be saved
3334 */
3335static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
3336{
3337 struct smack_known *iskp = ipp->security;
3338
3339 *secid = iskp->smk_secid;
3340}
3341
3342/**
3343 * smack_d_instantiate - Make sure the blob is correct on an inode
3344 * @opt_dentry: dentry where inode will be attached
3345 * @inode: the object
3346 *
3347 * Set the inode's security blob if it hasn't been done already.
3348 */
3349static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3350{
3351 struct super_block *sbp;
3352 struct superblock_smack *sbsp;
3353 struct inode_smack *isp;
3354 struct smack_known *skp;
3355 struct smack_known *ckp = smk_of_current();
3356 struct smack_known *final;
3357 char trattr[TRANS_TRUE_SIZE];
3358 int transflag = 0;
3359 int rc;
3360 struct dentry *dp;
3361
3362 if (inode == NULL)
3363 return;
3364
3365 isp = inode->i_security;
3366
3367 mutex_lock(&isp->smk_lock);
3368 /*
3369 * If the inode is already instantiated
3370 * take the quick way out
3371 */
3372 if (isp->smk_flags & SMK_INODE_INSTANT)
3373 goto unlockandout;
3374
3375 sbp = inode->i_sb;
3376 sbsp = sbp->s_security;
3377 /*
3378 * We're going to use the superblock default label
3379 * if there's no label on the file.
3380 */
3381 final = sbsp->smk_default;
3382
3383 /*
3384 * If this is the root inode the superblock
3385 * may be in the process of initialization.
3386 * If that is the case use the root value out
3387 * of the superblock.
3388 */
3389 if (opt_dentry->d_parent == opt_dentry) {
3390 switch (sbp->s_magic) {
3391 case CGROUP_SUPER_MAGIC:
3392 /*
3393 * The cgroup filesystem is never mounted,
3394 * so there's no opportunity to set the mount
3395 * options.
3396 */
3397 sbsp->smk_root = &smack_known_star;
3398 sbsp->smk_default = &smack_known_star;
3399 isp->smk_inode = sbsp->smk_root;
3400 break;
3401 case TMPFS_MAGIC:
3402 /*
3403 * What about shmem/tmpfs anonymous files with dentry
3404 * obtained from d_alloc_pseudo()?
3405 */
3406 isp->smk_inode = smk_of_current();
3407 break;
3408 case PIPEFS_MAGIC:
3409 isp->smk_inode = smk_of_current();
3410 break;
3411 default:
3412 isp->smk_inode = sbsp->smk_root;
3413 break;
3414 }
3415 isp->smk_flags |= SMK_INODE_INSTANT;
3416 goto unlockandout;
3417 }
3418
3419 /*
3420 * This is pretty hackish.
3421 * Casey says that we shouldn't have to do
3422 * file system specific code, but it does help
3423 * with keeping it simple.
3424 */
3425 switch (sbp->s_magic) {
3426 case SMACK_MAGIC:
3427 case PIPEFS_MAGIC:
3428 case SOCKFS_MAGIC:
3429 case CGROUP_SUPER_MAGIC:
3430 /*
3431 * Casey says that it's a little embarrassing
3432 * that the smack file system doesn't do
3433 * extended attributes.
3434 *
3435 * Casey says pipes are easy (?)
3436 *
3437 * Socket access is controlled by the socket
3438 * structures associated with the task involved.
3439 *
3440 * Cgroupfs is special
3441 */
3442 final = &smack_known_star;
3443 break;
3444 case DEVPTS_SUPER_MAGIC:
3445 /*
3446 * devpts seems content with the label of the task.
3447 * Programs that change smack have to treat the
3448 * pty with respect.
3449 */
3450 final = ckp;
3451 break;
3452 case PROC_SUPER_MAGIC:
3453 /*
3454 * Casey says procfs appears not to care.
3455 * The superblock default suffices.
3456 */
3457 break;
3458 case TMPFS_MAGIC:
3459 /*
3460 * Device labels should come from the filesystem,
3461 * but watch out, because they're volitile,
3462 * getting recreated on every reboot.
3463 */
3464 final = &smack_known_star;
3465 /*
3466 * No break.
3467 *
3468 * If a smack value has been set we want to use it,
3469 * but since tmpfs isn't giving us the opportunity
3470 * to set mount options simulate setting the
3471 * superblock default.
3472 */
3473 default:
3474 /*
3475 * This isn't an understood special case.
3476 * Get the value from the xattr.
3477 */
3478
3479 /*
3480 * UNIX domain sockets use lower level socket data.
3481 */
3482 if (S_ISSOCK(inode->i_mode)) {
3483 final = &smack_known_star;
3484 break;
3485 }
3486 /*
3487 * No xattr support means, alas, no SMACK label.
3488 * Use the aforeapplied default.
3489 * It would be curious if the label of the task
3490 * does not match that assigned.
3491 */
3492 if (inode->i_op->getxattr == NULL)
3493 break;
3494 /*
3495 * Get the dentry for xattr.
3496 */
3497 dp = dget(opt_dentry);
3498 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3499 if (!IS_ERR_OR_NULL(skp))
3500 final = skp;
3501
3502 /*
3503 * Transmuting directory
3504 */
3505 if (S_ISDIR(inode->i_mode)) {
3506 /*
3507 * If this is a new directory and the label was
3508 * transmuted when the inode was initialized
3509 * set the transmute attribute on the directory
3510 * and mark the inode.
3511 *
3512 * If there is a transmute attribute on the
3513 * directory mark the inode.
3514 */
3515 if (isp->smk_flags & SMK_INODE_CHANGED) {
3516 isp->smk_flags &= ~SMK_INODE_CHANGED;
3517 rc = inode->i_op->setxattr(dp,
3518 XATTR_NAME_SMACKTRANSMUTE,
3519 TRANS_TRUE, TRANS_TRUE_SIZE,
3520 0);
3521 } else {
3522 rc = inode->i_op->getxattr(dp,
3523 XATTR_NAME_SMACKTRANSMUTE, trattr,
3524 TRANS_TRUE_SIZE);
3525 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3526 TRANS_TRUE_SIZE) != 0)
3527 rc = -EINVAL;
3528 }
3529 if (rc >= 0)
3530 transflag = SMK_INODE_TRANSMUTE;
3531 }
3532 /*
3533 * Don't let the exec or mmap label be "*" or "@".
3534 */
3535 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3536 if (IS_ERR(skp) || skp == &smack_known_star ||
3537 skp == &smack_known_web)
3538 skp = NULL;
3539 isp->smk_task = skp;
3540
3541 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3542 if (IS_ERR(skp) || skp == &smack_known_star ||
3543 skp == &smack_known_web)
3544 skp = NULL;
3545 isp->smk_mmap = skp;
3546
3547 dput(dp);
3548 break;
3549 }
3550
3551 if (final == NULL)
3552 isp->smk_inode = ckp;
3553 else
3554 isp->smk_inode = final;
3555
3556 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3557
3558unlockandout:
3559 mutex_unlock(&isp->smk_lock);
3560 return;
3561}
3562
3563/**
3564 * smack_getprocattr - Smack process attribute access
3565 * @p: the object task
3566 * @name: the name of the attribute in /proc/.../attr
3567 * @value: where to put the result
3568 *
3569 * Places a copy of the task Smack into value
3570 *
3571 * Returns the length of the smack label or an error code
3572 */
3573static int smack_getprocattr(struct task_struct *p, char *name, char **value)
3574{
3575 struct smack_known *skp = smk_of_task_struct(p);
3576 char *cp;
3577 int slen;
3578
3579 if (strcmp(name, "current") != 0)
3580 return -EINVAL;
3581
3582 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3583 if (cp == NULL)
3584 return -ENOMEM;
3585
3586 slen = strlen(cp);
3587 *value = cp;
3588 return slen;
3589}
3590
3591/**
3592 * smack_setprocattr - Smack process attribute setting
3593 * @p: the object task
3594 * @name: the name of the attribute in /proc/.../attr
3595 * @value: the value to set
3596 * @size: the size of the value
3597 *
3598 * Sets the Smack value of the task. Only setting self
3599 * is permitted and only with privilege
3600 *
3601 * Returns the length of the smack label or an error code
3602 */
3603static int smack_setprocattr(struct task_struct *p, char *name,
3604 void *value, size_t size)
3605{
3606 struct task_smack *tsp = current_security();
3607 struct cred *new;
3608 struct smack_known *skp;
3609 struct smack_known_list_elem *sklep;
3610 int rc;
3611
3612 /*
3613 * Changing another process' Smack value is too dangerous
3614 * and supports no sane use case.
3615 */
3616 if (p != current)
3617 return -EPERM;
3618
3619 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3620 return -EPERM;
3621
3622 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3623 return -EINVAL;
3624
3625 if (strcmp(name, "current") != 0)
3626 return -EINVAL;
3627
3628 skp = smk_import_entry(value, size);
3629 if (IS_ERR(skp))
3630 return PTR_ERR(skp);
3631
3632 /*
3633 * No process is ever allowed the web ("@") label.
3634 */
3635 if (skp == &smack_known_web)
3636 return -EPERM;
3637
3638 if (!smack_privileged(CAP_MAC_ADMIN)) {
3639 rc = -EPERM;
3640 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3641 if (sklep->smk_label == skp) {
3642 rc = 0;
3643 break;
3644 }
3645 if (rc)
3646 return rc;
3647 }
3648
3649 new = prepare_creds();
3650 if (new == NULL)
3651 return -ENOMEM;
3652
3653 tsp = new->security;
3654 tsp->smk_task = skp;
3655 /*
3656 * process can change its label only once
3657 */
3658 smk_destroy_label_list(&tsp->smk_relabel);
3659
3660 commit_creds(new);
3661 return size;
3662}
3663
3664/**
3665 * smack_unix_stream_connect - Smack access on UDS
3666 * @sock: one sock
3667 * @other: the other sock
3668 * @newsk: unused
3669 *
3670 * Return 0 if a subject with the smack of sock could access
3671 * an object with the smack of other, otherwise an error code
3672 */
3673static int smack_unix_stream_connect(struct sock *sock,
3674 struct sock *other, struct sock *newsk)
3675{
3676 struct smack_known *skp;
3677 struct smack_known *okp;
3678 struct socket_smack *ssp = sock->sk_security;
3679 struct socket_smack *osp = other->sk_security;
3680 struct socket_smack *nsp = newsk->sk_security;
3681 struct smk_audit_info ad;
3682 int rc = 0;
3683#ifdef CONFIG_AUDIT
3684 struct lsm_network_audit net;
3685#endif
3686
3687 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3688 skp = ssp->smk_out;
3689 okp = osp->smk_in;
3690#ifdef CONFIG_AUDIT
3691 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3692 smk_ad_setfield_u_net_sk(&ad, other);
3693#endif
3694 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3695 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3696 if (rc == 0) {
3697 okp = osp->smk_out;
3698 skp = ssp->smk_in;
3699 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3700 rc = smk_bu_note("UDS connect", okp, skp,
3701 MAY_WRITE, rc);
3702 }
3703 }
3704
3705 /*
3706 * Cross reference the peer labels for SO_PEERSEC.
3707 */
3708 if (rc == 0) {
3709 nsp->smk_packet = ssp->smk_out;
3710 ssp->smk_packet = osp->smk_out;
3711 }
3712
3713 return rc;
3714}
3715
3716/**
3717 * smack_unix_may_send - Smack access on UDS
3718 * @sock: one socket
3719 * @other: the other socket
3720 *
3721 * Return 0 if a subject with the smack of sock could access
3722 * an object with the smack of other, otherwise an error code
3723 */
3724static int smack_unix_may_send(struct socket *sock, struct socket *other)
3725{
3726 struct socket_smack *ssp = sock->sk->sk_security;
3727 struct socket_smack *osp = other->sk->sk_security;
3728 struct smk_audit_info ad;
3729 int rc;
3730
3731#ifdef CONFIG_AUDIT
3732 struct lsm_network_audit net;
3733
3734 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3735 smk_ad_setfield_u_net_sk(&ad, other->sk);
3736#endif
3737
3738 if (smack_privileged(CAP_MAC_OVERRIDE))
3739 return 0;
3740
3741 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3742 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3743 return rc;
3744}
3745
3746/**
3747 * smack_socket_sendmsg - Smack check based on destination host
3748 * @sock: the socket
3749 * @msg: the message
3750 * @size: the size of the message
3751 *
3752 * Return 0 if the current subject can write to the destination host.
3753 * For IPv4 this is only a question if the destination is a single label host.
3754 * For IPv6 this is a check against the label of the port.
3755 */
3756static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3757 int size)
3758{
3759 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3760#if IS_ENABLED(CONFIG_IPV6)
3761 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3762#endif
3763#ifdef SMACK_IPV6_SECMARK_LABELING
3764 struct socket_smack *ssp = sock->sk->sk_security;
3765 struct smack_known *rsp;
3766#endif
3767 int rc = 0;
3768
3769 /*
3770 * Perfectly reasonable for this to be NULL
3771 */
3772 if (sip == NULL)
3773 return 0;
3774
3775 switch (sock->sk->sk_family) {
3776 case AF_INET:
3777 rc = smack_netlabel_send(sock->sk, sip);
3778 break;
3779 case AF_INET6:
3780#ifdef SMACK_IPV6_SECMARK_LABELING
3781 rsp = smack_ipv6host_label(sap);
3782 if (rsp != NULL)
3783 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3784 SMK_CONNECTING);
3785#endif
3786#ifdef SMACK_IPV6_PORT_LABELING
3787 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3788#endif
3789 break;
3790 }
3791 return rc;
3792}
3793
3794/**
3795 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3796 * @sap: netlabel secattr
3797 * @ssp: socket security information
3798 *
3799 * Returns a pointer to a Smack label entry found on the label list.
3800 */
3801static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3802 struct socket_smack *ssp)
3803{
3804 struct smack_known *skp;
3805 int found = 0;
3806 int acat;
3807 int kcat;
3808
3809 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3810 /*
3811 * Looks like a CIPSO packet.
3812 * If there are flags but no level netlabel isn't
3813 * behaving the way we expect it to.
3814 *
3815 * Look it up in the label table
3816 * Without guidance regarding the smack value
3817 * for the packet fall back on the network
3818 * ambient value.
3819 */
3820 rcu_read_lock();
3821 list_for_each_entry(skp, &smack_known_list, list) {
3822 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3823 continue;
3824 /*
3825 * Compare the catsets. Use the netlbl APIs.
3826 */
3827 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
3828 if ((skp->smk_netlabel.flags &
3829 NETLBL_SECATTR_MLS_CAT) == 0)
3830 found = 1;
3831 break;
3832 }
3833 for (acat = -1, kcat = -1; acat == kcat; ) {
3834 acat = netlbl_catmap_walk(sap->attr.mls.cat,
3835 acat + 1);
3836 kcat = netlbl_catmap_walk(
3837 skp->smk_netlabel.attr.mls.cat,
3838 kcat + 1);
3839 if (acat < 0 || kcat < 0)
3840 break;
3841 }
3842 if (acat == kcat) {
3843 found = 1;
3844 break;
3845 }
3846 }
3847 rcu_read_unlock();
3848
3849 if (found)
3850 return skp;
3851
3852 if (ssp != NULL && ssp->smk_in == &smack_known_star)
3853 return &smack_known_web;
3854 return &smack_known_star;
3855 }
3856 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
3857 /*
3858 * Looks like a fallback, which gives us a secid.
3859 */
3860 skp = smack_from_secid(sap->attr.secid);
3861 /*
3862 * This has got to be a bug because it is
3863 * impossible to specify a fallback without
3864 * specifying the label, which will ensure
3865 * it has a secid, and the only way to get a
3866 * secid is from a fallback.
3867 */
3868 BUG_ON(skp == NULL);
3869 return skp;
3870 }
3871 /*
3872 * Without guidance regarding the smack value
3873 * for the packet fall back on the network
3874 * ambient value.
3875 */
3876 return smack_net_ambient;
3877}
3878
3879#if IS_ENABLED(CONFIG_IPV6)
3880static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
3881{
3882 u8 nexthdr;
3883 int offset;
3884 int proto = -EINVAL;
3885 struct ipv6hdr _ipv6h;
3886 struct ipv6hdr *ip6;
3887 __be16 frag_off;
3888 struct tcphdr _tcph, *th;
3889 struct udphdr _udph, *uh;
3890 struct dccp_hdr _dccph, *dh;
3891
3892 sip->sin6_port = 0;
3893
3894 offset = skb_network_offset(skb);
3895 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3896 if (ip6 == NULL)
3897 return -EINVAL;
3898 sip->sin6_addr = ip6->saddr;
3899
3900 nexthdr = ip6->nexthdr;
3901 offset += sizeof(_ipv6h);
3902 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3903 if (offset < 0)
3904 return -EINVAL;
3905
3906 proto = nexthdr;
3907 switch (proto) {
3908 case IPPROTO_TCP:
3909 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3910 if (th != NULL)
3911 sip->sin6_port = th->source;
3912 break;
3913 case IPPROTO_UDP:
3914 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3915 if (uh != NULL)
3916 sip->sin6_port = uh->source;
3917 break;
3918 case IPPROTO_DCCP:
3919 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3920 if (dh != NULL)
3921 sip->sin6_port = dh->dccph_sport;
3922 break;
3923 }
3924 return proto;
3925}
3926#endif /* CONFIG_IPV6 */
3927
3928/**
3929 * smack_socket_sock_rcv_skb - Smack packet delivery access check
3930 * @sk: socket
3931 * @skb: packet
3932 *
3933 * Returns 0 if the packet should be delivered, an error code otherwise
3934 */
3935static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3936{
3937 struct netlbl_lsm_secattr secattr;
3938 struct socket_smack *ssp = sk->sk_security;
3939 struct smack_known *skp = NULL;
3940 int rc = 0;
3941 struct smk_audit_info ad;
3942#ifdef CONFIG_AUDIT
3943 struct lsm_network_audit net;
3944#endif
3945#if IS_ENABLED(CONFIG_IPV6)
3946 struct sockaddr_in6 sadd;
3947 int proto;
3948#endif /* CONFIG_IPV6 */
3949
3950 switch (sk->sk_family) {
3951 case PF_INET:
3952#ifdef CONFIG_SECURITY_SMACK_NETFILTER
3953 /*
3954 * If there is a secmark use it rather than the CIPSO label.
3955 * If there is no secmark fall back to CIPSO.
3956 * The secmark is assumed to reflect policy better.
3957 */
3958 if (skb && skb->secmark != 0) {
3959 skp = smack_from_secid(skb->secmark);
3960 goto access_check;
3961 }
3962#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
3963 /*
3964 * Translate what netlabel gave us.
3965 */
3966 netlbl_secattr_init(&secattr);
3967
3968 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3969 if (rc == 0)
3970 skp = smack_from_secattr(&secattr, ssp);
3971 else
3972 skp = smack_net_ambient;
3973
3974 netlbl_secattr_destroy(&secattr);
3975
3976#ifdef CONFIG_SECURITY_SMACK_NETFILTER
3977access_check:
3978#endif
3979#ifdef CONFIG_AUDIT
3980 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3981 ad.a.u.net->family = sk->sk_family;
3982 ad.a.u.net->netif = skb->skb_iif;
3983 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3984#endif
3985 /*
3986 * Receiving a packet requires that the other end
3987 * be able to write here. Read access is not required.
3988 * This is the simplist possible security model
3989 * for networking.
3990 */
3991 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
3992 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
3993 MAY_WRITE, rc);
3994 if (rc != 0)
3995 netlbl_skbuff_err(skb, rc, 0);
3996 break;
3997#if IS_ENABLED(CONFIG_IPV6)
3998 case PF_INET6:
3999 proto = smk_skb_to_addr_ipv6(skb, &sadd);
4000 if (proto != IPPROTO_UDP && proto != IPPROTO_TCP)
4001 break;
4002#ifdef SMACK_IPV6_SECMARK_LABELING
4003 if (skb && skb->secmark != 0)
4004 skp = smack_from_secid(skb->secmark);
4005 else
4006 skp = smack_ipv6host_label(&sadd);
4007 if (skp == NULL)
4008 skp = smack_net_ambient;
4009#ifdef CONFIG_AUDIT
4010 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4011 ad.a.u.net->family = sk->sk_family;
4012 ad.a.u.net->netif = skb->skb_iif;
4013 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
4014#endif /* CONFIG_AUDIT */
4015 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4016 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
4017 MAY_WRITE, rc);
4018#endif /* SMACK_IPV6_SECMARK_LABELING */
4019#ifdef SMACK_IPV6_PORT_LABELING
4020 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
4021#endif /* SMACK_IPV6_PORT_LABELING */
4022 break;
4023#endif /* CONFIG_IPV6 */
4024 }
4025
4026 return rc;
4027}
4028
4029/**
4030 * smack_socket_getpeersec_stream - pull in packet label
4031 * @sock: the socket
4032 * @optval: user's destination
4033 * @optlen: size thereof
4034 * @len: max thereof
4035 *
4036 * returns zero on success, an error code otherwise
4037 */
4038static int smack_socket_getpeersec_stream(struct socket *sock,
4039 char __user *optval,
4040 int __user *optlen, unsigned len)
4041{
4042 struct socket_smack *ssp;
4043 char *rcp = "";
4044 int slen = 1;
4045 int rc = 0;
4046
4047 ssp = sock->sk->sk_security;
4048 if (ssp->smk_packet != NULL) {
4049 rcp = ssp->smk_packet->smk_known;
4050 slen = strlen(rcp) + 1;
4051 }
4052
4053 if (slen > len)
4054 rc = -ERANGE;
4055 else if (copy_to_user(optval, rcp, slen) != 0)
4056 rc = -EFAULT;
4057
4058 if (put_user(slen, optlen) != 0)
4059 rc = -EFAULT;
4060
4061 return rc;
4062}
4063
4064
4065/**
4066 * smack_socket_getpeersec_dgram - pull in packet label
4067 * @sock: the peer socket
4068 * @skb: packet data
4069 * @secid: pointer to where to put the secid of the packet
4070 *
4071 * Sets the netlabel socket state on sk from parent
4072 */
4073static int smack_socket_getpeersec_dgram(struct socket *sock,
4074 struct sk_buff *skb, u32 *secid)
4075
4076{
4077 struct netlbl_lsm_secattr secattr;
4078 struct socket_smack *ssp = NULL;
4079 struct smack_known *skp;
4080 int family = PF_UNSPEC;
4081 u32 s = 0; /* 0 is the invalid secid */
4082 int rc;
4083
4084 if (skb != NULL) {
4085 if (skb->protocol == htons(ETH_P_IP))
4086 family = PF_INET;
4087#if IS_ENABLED(CONFIG_IPV6)
4088 else if (skb->protocol == htons(ETH_P_IPV6))
4089 family = PF_INET6;
4090#endif /* CONFIG_IPV6 */
4091 }
4092 if (family == PF_UNSPEC && sock != NULL)
4093 family = sock->sk->sk_family;
4094
4095 switch (family) {
4096 case PF_UNIX:
4097 ssp = sock->sk->sk_security;
4098 s = ssp->smk_out->smk_secid;
4099 break;
4100 case PF_INET:
4101#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4102 s = skb->secmark;
4103 if (s != 0)
4104 break;
4105#endif
4106 /*
4107 * Translate what netlabel gave us.
4108 */
4109 if (sock != NULL && sock->sk != NULL)
4110 ssp = sock->sk->sk_security;
4111 netlbl_secattr_init(&secattr);
4112 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4113 if (rc == 0) {
4114 skp = smack_from_secattr(&secattr, ssp);
4115 s = skp->smk_secid;
4116 }
4117 netlbl_secattr_destroy(&secattr);
4118 break;
4119 case PF_INET6:
4120#ifdef SMACK_IPV6_SECMARK_LABELING
4121 s = skb->secmark;
4122#endif
4123 break;
4124 }
4125 *secid = s;
4126 if (s == 0)
4127 return -EINVAL;
4128 return 0;
4129}
4130
4131/**
4132 * smack_sock_graft - Initialize a newly created socket with an existing sock
4133 * @sk: child sock
4134 * @parent: parent socket
4135 *
4136 * Set the smk_{in,out} state of an existing sock based on the process that
4137 * is creating the new socket.
4138 */
4139static void smack_sock_graft(struct sock *sk, struct socket *parent)
4140{
4141 struct socket_smack *ssp;
4142 struct smack_known *skp = smk_of_current();
4143
4144 if (sk == NULL ||
4145 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4146 return;
4147
4148 ssp = sk->sk_security;
4149 ssp->smk_in = skp;
4150 ssp->smk_out = skp;
4151 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4152}
4153
4154/**
4155 * smack_inet_conn_request - Smack access check on connect
4156 * @sk: socket involved
4157 * @skb: packet
4158 * @req: unused
4159 *
4160 * Returns 0 if a task with the packet label could write to
4161 * the socket, otherwise an error code
4162 */
4163static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4164 struct request_sock *req)
4165{
4166 u16 family = sk->sk_family;
4167 struct smack_known *skp;
4168 struct socket_smack *ssp = sk->sk_security;
4169 struct netlbl_lsm_secattr secattr;
4170 struct sockaddr_in addr;
4171 struct iphdr *hdr;
4172 struct smack_known *hskp;
4173 int rc;
4174 struct smk_audit_info ad;
4175#ifdef CONFIG_AUDIT
4176 struct lsm_network_audit net;
4177#endif
4178
4179#if IS_ENABLED(CONFIG_IPV6)
4180 if (family == PF_INET6) {
4181 /*
4182 * Handle mapped IPv4 packets arriving
4183 * via IPv6 sockets. Don't set up netlabel
4184 * processing on IPv6.
4185 */
4186 if (skb->protocol == htons(ETH_P_IP))
4187 family = PF_INET;
4188 else
4189 return 0;
4190 }
4191#endif /* CONFIG_IPV6 */
4192
4193#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4194 /*
4195 * If there is a secmark use it rather than the CIPSO label.
4196 * If there is no secmark fall back to CIPSO.
4197 * The secmark is assumed to reflect policy better.
4198 */
4199 if (skb && skb->secmark != 0) {
4200 skp = smack_from_secid(skb->secmark);
4201 goto access_check;
4202 }
4203#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
4204
4205 netlbl_secattr_init(&secattr);
4206 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4207 if (rc == 0)
4208 skp = smack_from_secattr(&secattr, ssp);
4209 else
4210 skp = &smack_known_huh;
4211 netlbl_secattr_destroy(&secattr);
4212
4213#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4214access_check:
4215#endif
4216
4217#ifdef CONFIG_AUDIT
4218 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4219 ad.a.u.net->family = family;
4220 ad.a.u.net->netif = skb->skb_iif;
4221 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4222#endif
4223 /*
4224 * Receiving a packet requires that the other end be able to write
4225 * here. Read access is not required.
4226 */
4227 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4228 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4229 if (rc != 0)
4230 return rc;
4231
4232 /*
4233 * Save the peer's label in the request_sock so we can later setup
4234 * smk_packet in the child socket so that SO_PEERCRED can report it.
4235 */
4236 req->peer_secid = skp->smk_secid;
4237
4238 /*
4239 * We need to decide if we want to label the incoming connection here
4240 * if we do we only need to label the request_sock and the stack will
4241 * propagate the wire-label to the sock when it is created.
4242 */
4243 hdr = ip_hdr(skb);
4244 addr.sin_addr.s_addr = hdr->saddr;
4245 rcu_read_lock();
4246 hskp = smack_ipv4host_label(&addr);
4247 rcu_read_unlock();
4248
4249 if (hskp == NULL)
4250 rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4251 else
4252 netlbl_req_delattr(req);
4253
4254 return rc;
4255}
4256
4257/**
4258 * smack_inet_csk_clone - Copy the connection information to the new socket
4259 * @sk: the new socket
4260 * @req: the connection's request_sock
4261 *
4262 * Transfer the connection's peer label to the newly created socket.
4263 */
4264static void smack_inet_csk_clone(struct sock *sk,
4265 const struct request_sock *req)
4266{
4267 struct socket_smack *ssp = sk->sk_security;
4268 struct smack_known *skp;
4269
4270 if (req->peer_secid != 0) {
4271 skp = smack_from_secid(req->peer_secid);
4272 ssp->smk_packet = skp;
4273 } else
4274 ssp->smk_packet = NULL;
4275}
4276
4277/*
4278 * Key management security hooks
4279 *
4280 * Casey has not tested key support very heavily.
4281 * The permission check is most likely too restrictive.
4282 * If you care about keys please have a look.
4283 */
4284#ifdef CONFIG_KEYS
4285
4286/**
4287 * smack_key_alloc - Set the key security blob
4288 * @key: object
4289 * @cred: the credentials to use
4290 * @flags: unused
4291 *
4292 * No allocation required
4293 *
4294 * Returns 0
4295 */
4296static int smack_key_alloc(struct key *key, const struct cred *cred,
4297 unsigned long flags)
4298{
4299 struct smack_known *skp = smk_of_task(cred->security);
4300
4301 key->security = skp;
4302 return 0;
4303}
4304
4305/**
4306 * smack_key_free - Clear the key security blob
4307 * @key: the object
4308 *
4309 * Clear the blob pointer
4310 */
4311static void smack_key_free(struct key *key)
4312{
4313 key->security = NULL;
4314}
4315
4316/**
4317 * smack_key_permission - Smack access on a key
4318 * @key_ref: gets to the object
4319 * @cred: the credentials to use
4320 * @perm: requested key permissions
4321 *
4322 * Return 0 if the task has read and write to the object,
4323 * an error code otherwise
4324 */
4325static int smack_key_permission(key_ref_t key_ref,
4326 const struct cred *cred, unsigned perm)
4327{
4328 struct key *keyp;
4329 struct smk_audit_info ad;
4330 struct smack_known *tkp = smk_of_task(cred->security);
4331 int request = 0;
4332 int rc;
4333
4334 keyp = key_ref_to_ptr(key_ref);
4335 if (keyp == NULL)
4336 return -EINVAL;
4337 /*
4338 * If the key hasn't been initialized give it access so that
4339 * it may do so.
4340 */
4341 if (keyp->security == NULL)
4342 return 0;
4343 /*
4344 * This should not occur
4345 */
4346 if (tkp == NULL)
4347 return -EACCES;
4348#ifdef CONFIG_AUDIT
4349 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4350 ad.a.u.key_struct.key = keyp->serial;
4351 ad.a.u.key_struct.key_desc = keyp->description;
4352#endif
4353 if (perm & KEY_NEED_READ)
4354 request = MAY_READ;
4355 if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
4356 request = MAY_WRITE;
4357 rc = smk_access(tkp, keyp->security, request, &ad);
4358 rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
4359 return rc;
4360}
4361
4362/*
4363 * smack_key_getsecurity - Smack label tagging the key
4364 * @key points to the key to be queried
4365 * @_buffer points to a pointer that should be set to point to the
4366 * resulting string (if no label or an error occurs).
4367 * Return the length of the string (including terminating NUL) or -ve if
4368 * an error.
4369 * May also return 0 (and a NULL buffer pointer) if there is no label.
4370 */
4371static int smack_key_getsecurity(struct key *key, char **_buffer)
4372{
4373 struct smack_known *skp = key->security;
4374 size_t length;
4375 char *copy;
4376
4377 if (key->security == NULL) {
4378 *_buffer = NULL;
4379 return 0;
4380 }
4381
4382 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4383 if (copy == NULL)
4384 return -ENOMEM;
4385 length = strlen(copy) + 1;
4386
4387 *_buffer = copy;
4388 return length;
4389}
4390
4391#endif /* CONFIG_KEYS */
4392
4393/*
4394 * Smack Audit hooks
4395 *
4396 * Audit requires a unique representation of each Smack specific
4397 * rule. This unique representation is used to distinguish the
4398 * object to be audited from remaining kernel objects and also
4399 * works as a glue between the audit hooks.
4400 *
4401 * Since repository entries are added but never deleted, we'll use
4402 * the smack_known label address related to the given audit rule as
4403 * the needed unique representation. This also better fits the smack
4404 * model where nearly everything is a label.
4405 */
4406#ifdef CONFIG_AUDIT
4407
4408/**
4409 * smack_audit_rule_init - Initialize a smack audit rule
4410 * @field: audit rule fields given from user-space (audit.h)
4411 * @op: required testing operator (=, !=, >, <, ...)
4412 * @rulestr: smack label to be audited
4413 * @vrule: pointer to save our own audit rule representation
4414 *
4415 * Prepare to audit cases where (@field @op @rulestr) is true.
4416 * The label to be audited is created if necessay.
4417 */
4418static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
4419{
4420 struct smack_known *skp;
4421 char **rule = (char **)vrule;
4422 *rule = NULL;
4423
4424 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4425 return -EINVAL;
4426
4427 if (op != Audit_equal && op != Audit_not_equal)
4428 return -EINVAL;
4429
4430 skp = smk_import_entry(rulestr, 0);
4431 if (IS_ERR(skp))
4432 return PTR_ERR(skp);
4433
4434 *rule = skp->smk_known;
4435
4436 return 0;
4437}
4438
4439/**
4440 * smack_audit_rule_known - Distinguish Smack audit rules
4441 * @krule: rule of interest, in Audit kernel representation format
4442 *
4443 * This is used to filter Smack rules from remaining Audit ones.
4444 * If it's proved that this rule belongs to us, the
4445 * audit_rule_match hook will be called to do the final judgement.
4446 */
4447static int smack_audit_rule_known(struct audit_krule *krule)
4448{
4449 struct audit_field *f;
4450 int i;
4451
4452 for (i = 0; i < krule->field_count; i++) {
4453 f = &krule->fields[i];
4454
4455 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4456 return 1;
4457 }
4458
4459 return 0;
4460}
4461
4462/**
4463 * smack_audit_rule_match - Audit given object ?
4464 * @secid: security id for identifying the object to test
4465 * @field: audit rule flags given from user-space
4466 * @op: required testing operator
4467 * @vrule: smack internal rule presentation
4468 * @actx: audit context associated with the check
4469 *
4470 * The core Audit hook. It's used to take the decision of
4471 * whether to audit or not to audit a given object.
4472 */
4473static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
4474 struct audit_context *actx)
4475{
4476 struct smack_known *skp;
4477 char *rule = vrule;
4478
4479 if (unlikely(!rule)) {
4480 WARN_ONCE(1, "Smack: missing rule\n");
4481 return -ENOENT;
4482 }
4483
4484 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4485 return 0;
4486
4487 skp = smack_from_secid(secid);
4488
4489 /*
4490 * No need to do string comparisons. If a match occurs,
4491 * both pointers will point to the same smack_known
4492 * label.
4493 */
4494 if (op == Audit_equal)
4495 return (rule == skp->smk_known);
4496 if (op == Audit_not_equal)
4497 return (rule != skp->smk_known);
4498
4499 return 0;
4500}
4501
4502/*
4503 * There is no need for a smack_audit_rule_free hook.
4504 * No memory was allocated.
4505 */
4506
4507#endif /* CONFIG_AUDIT */
4508
4509/**
4510 * smack_ismaclabel - check if xattr @name references a smack MAC label
4511 * @name: Full xattr name to check.
4512 */
4513static int smack_ismaclabel(const char *name)
4514{
4515 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4516}
4517
4518
4519/**
4520 * smack_secid_to_secctx - return the smack label for a secid
4521 * @secid: incoming integer
4522 * @secdata: destination
4523 * @seclen: how long it is
4524 *
4525 * Exists for networking code.
4526 */
4527static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4528{
4529 struct smack_known *skp = smack_from_secid(secid);
4530
4531 if (secdata)
4532 *secdata = skp->smk_known;
4533 *seclen = strlen(skp->smk_known);
4534 return 0;
4535}
4536
4537/**
4538 * smack_secctx_to_secid - return the secid for a smack label
4539 * @secdata: smack label
4540 * @seclen: how long result is
4541 * @secid: outgoing integer
4542 *
4543 * Exists for audit and networking code.
4544 */
4545static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4546{
4547 struct smack_known *skp = smk_find_entry(secdata);
4548
4549 if (skp)
4550 *secid = skp->smk_secid;
4551 else
4552 *secid = 0;
4553 return 0;
4554}
4555
4556/*
4557 * There used to be a smack_release_secctx hook
4558 * that did nothing back when hooks were in a vector.
4559 * Now that there's a list such a hook adds cost.
4560 */
4561
4562static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4563{
4564 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
4565}
4566
4567static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4568{
4569 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
4570}
4571
4572static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4573{
4574 int len = 0;
4575 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
4576
4577 if (len < 0)
4578 return len;
4579 *ctxlen = len;
4580 return 0;
4581}
4582
4583static struct security_hook_list smack_hooks[] = {
4584 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
4585 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
4586 LSM_HOOK_INIT(syslog, smack_syslog),
4587
4588 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
4589 LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
4590 LSM_HOOK_INIT(sb_copy_data, smack_sb_copy_data),
4591 LSM_HOOK_INIT(sb_kern_mount, smack_sb_kern_mount),
4592 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
4593 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
4594 LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str),
4595
4596 LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
4597 LSM_HOOK_INIT(bprm_committing_creds, smack_bprm_committing_creds),
4598 LSM_HOOK_INIT(bprm_secureexec, smack_bprm_secureexec),
4599
4600 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
4601 LSM_HOOK_INIT(inode_free_security, smack_inode_free_security),
4602 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
4603 LSM_HOOK_INIT(inode_link, smack_inode_link),
4604 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
4605 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
4606 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
4607 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
4608 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
4609 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
4610 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
4611 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
4612 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
4613 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
4614 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
4615 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
4616 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
4617 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
4618
4619 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
4620 LSM_HOOK_INIT(file_free_security, smack_file_free_security),
4621 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
4622 LSM_HOOK_INIT(file_lock, smack_file_lock),
4623 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
4624 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
4625 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
4626 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
4627 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
4628 LSM_HOOK_INIT(file_receive, smack_file_receive),
4629
4630 LSM_HOOK_INIT(file_open, smack_file_open),
4631
4632 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
4633 LSM_HOOK_INIT(cred_free, smack_cred_free),
4634 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
4635 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
4636 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
4637 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
4638 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
4639 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
4640 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
4641 LSM_HOOK_INIT(task_getsecid, smack_task_getsecid),
4642 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
4643 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
4644 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
4645 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
4646 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
4647 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
4648 LSM_HOOK_INIT(task_kill, smack_task_kill),
4649 LSM_HOOK_INIT(task_wait, smack_task_wait),
4650 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
4651
4652 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
4653 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
4654
4655 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
4656 LSM_HOOK_INIT(msg_msg_free_security, smack_msg_msg_free_security),
4657
4658 LSM_HOOK_INIT(msg_queue_alloc_security, smack_msg_queue_alloc_security),
4659 LSM_HOOK_INIT(msg_queue_free_security, smack_msg_queue_free_security),
4660 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
4661 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
4662 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
4663 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
4664
4665 LSM_HOOK_INIT(shm_alloc_security, smack_shm_alloc_security),
4666 LSM_HOOK_INIT(shm_free_security, smack_shm_free_security),
4667 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
4668 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
4669 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
4670
4671 LSM_HOOK_INIT(sem_alloc_security, smack_sem_alloc_security),
4672 LSM_HOOK_INIT(sem_free_security, smack_sem_free_security),
4673 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
4674 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
4675 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
4676
4677 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
4678
4679 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
4680 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
4681
4682 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
4683 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
4684
4685 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
4686#ifdef SMACK_IPV6_PORT_LABELING
4687 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
4688#endif
4689 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
4690 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
4691 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
4692 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
4693 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
4694 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
4695 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
4696 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
4697 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
4698 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
4699
4700 /* key management security hooks */
4701#ifdef CONFIG_KEYS
4702 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
4703 LSM_HOOK_INIT(key_free, smack_key_free),
4704 LSM_HOOK_INIT(key_permission, smack_key_permission),
4705 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
4706#endif /* CONFIG_KEYS */
4707
4708 /* Audit hooks */
4709#ifdef CONFIG_AUDIT
4710 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
4711 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
4712 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
4713#endif /* CONFIG_AUDIT */
4714
4715 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
4716 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
4717 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
4718 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
4719 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
4720 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
4721};
4722
4723
4724static __init void init_smack_known_list(void)
4725{
4726 /*
4727 * Initialize rule list locks
4728 */
4729 mutex_init(&smack_known_huh.smk_rules_lock);
4730 mutex_init(&smack_known_hat.smk_rules_lock);
4731 mutex_init(&smack_known_floor.smk_rules_lock);
4732 mutex_init(&smack_known_star.smk_rules_lock);
4733 mutex_init(&smack_known_invalid.smk_rules_lock);
4734 mutex_init(&smack_known_web.smk_rules_lock);
4735 /*
4736 * Initialize rule lists
4737 */
4738 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
4739 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
4740 INIT_LIST_HEAD(&smack_known_star.smk_rules);
4741 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
4742 INIT_LIST_HEAD(&smack_known_invalid.smk_rules);
4743 INIT_LIST_HEAD(&smack_known_web.smk_rules);
4744 /*
4745 * Create the known labels list
4746 */
4747 smk_insert_entry(&smack_known_huh);
4748 smk_insert_entry(&smack_known_hat);
4749 smk_insert_entry(&smack_known_star);
4750 smk_insert_entry(&smack_known_floor);
4751 smk_insert_entry(&smack_known_invalid);
4752 smk_insert_entry(&smack_known_web);
4753}
4754
4755/**
4756 * smack_init - initialize the smack system
4757 *
4758 * Returns 0
4759 */
4760static __init int smack_init(void)
4761{
4762 struct cred *cred;
4763 struct task_smack *tsp;
4764
4765 if (!security_module_enable("smack"))
4766 return 0;
4767
4768 smack_inode_cache = KMEM_CACHE(inode_smack, 0);
4769 if (!smack_inode_cache)
4770 return -ENOMEM;
4771
4772 tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
4773 GFP_KERNEL);
4774 if (tsp == NULL) {
4775 kmem_cache_destroy(smack_inode_cache);
4776 return -ENOMEM;
4777 }
4778
4779 smack_enabled = 1;
4780
4781 pr_info("Smack: Initializing.\n");
4782#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4783 pr_info("Smack: Netfilter enabled.\n");
4784#endif
4785#ifdef SMACK_IPV6_PORT_LABELING
4786 pr_info("Smack: IPv6 port labeling enabled.\n");
4787#endif
4788#ifdef SMACK_IPV6_SECMARK_LABELING
4789 pr_info("Smack: IPv6 Netfilter enabled.\n");
4790#endif
4791
4792 /*
4793 * Set the security state for the initial task.
4794 */
4795 cred = (struct cred *) current->cred;
4796 cred->security = tsp;
4797
4798 /* initialize the smack_known_list */
4799 init_smack_known_list();
4800
4801 /*
4802 * Register with LSM
4803 */
4804 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks));
4805
4806 return 0;
4807}
4808
4809/*
4810 * Smack requires early initialization in order to label
4811 * all processes and objects when they are created.
4812 */
4813security_initcall(smack_init);