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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// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Simplified MAC Kernel (smack) security module
4 *
5 * This file contains the smack hook function implementations.
6 *
7 * Authors:
8 * Casey Schaufler <casey@schaufler-ca.com>
9 * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
10 *
11 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
12 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
13 * Paul Moore <paul@paul-moore.com>
14 * Copyright (C) 2010 Nokia Corporation
15 * Copyright (C) 2011 Intel Corporation.
16 */
17
18#include <linux/xattr.h>
19#include <linux/pagemap.h>
20#include <linux/mount.h>
21#include <linux/stat.h>
22#include <linux/kd.h>
23#include <asm/ioctls.h>
24#include <linux/ip.h>
25#include <linux/tcp.h>
26#include <linux/udp.h>
27#include <linux/dccp.h>
28#include <linux/icmpv6.h>
29#include <linux/slab.h>
30#include <linux/mutex.h>
31#include <net/cipso_ipv4.h>
32#include <net/ip.h>
33#include <net/ipv6.h>
34#include <linux/audit.h>
35#include <linux/magic.h>
36#include <linux/dcache.h>
37#include <linux/personality.h>
38#include <linux/msg.h>
39#include <linux/shm.h>
40#include <uapi/linux/shm.h>
41#include <linux/binfmts.h>
42#include <linux/parser.h>
43#include <linux/fs_context.h>
44#include <linux/fs_parser.h>
45#include <linux/watch_queue.h>
46#include <linux/io_uring/cmd.h>
47#include <uapi/linux/lsm.h>
48#include "smack.h"
49
50#define TRANS_TRUE "TRUE"
51#define TRANS_TRUE_SIZE 4
52
53#define SMK_CONNECTING 0
54#define SMK_RECEIVING 1
55#define SMK_SENDING 2
56
57/*
58 * Smack uses multiple xattrs.
59 * SMACK64 - for access control,
60 * SMACK64TRANSMUTE - label initialization,
61 * Not saved on files - SMACK64IPIN and SMACK64IPOUT,
62 * Must be set explicitly - SMACK64EXEC and SMACK64MMAP
63 */
64#define SMACK_INODE_INIT_XATTRS 2
65
66#ifdef SMACK_IPV6_PORT_LABELING
67static DEFINE_MUTEX(smack_ipv6_lock);
68static LIST_HEAD(smk_ipv6_port_list);
69#endif
70struct kmem_cache *smack_rule_cache;
71int smack_enabled __initdata;
72
73#define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
74static struct {
75 const char *name;
76 int len;
77 int opt;
78} smk_mount_opts[] = {
79 {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault},
80 A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute)
81};
82#undef A
83
84static int match_opt_prefix(char *s, int l, char **arg)
85{
86 int i;
87
88 for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) {
89 size_t len = smk_mount_opts[i].len;
90 if (len > l || memcmp(s, smk_mount_opts[i].name, len))
91 continue;
92 if (len == l || s[len] != '=')
93 continue;
94 *arg = s + len + 1;
95 return smk_mount_opts[i].opt;
96 }
97 return Opt_error;
98}
99
100#ifdef CONFIG_SECURITY_SMACK_BRINGUP
101static char *smk_bu_mess[] = {
102 "Bringup Error", /* Unused */
103 "Bringup", /* SMACK_BRINGUP_ALLOW */
104 "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */
105 "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */
106};
107
108static void smk_bu_mode(int mode, char *s)
109{
110 int i = 0;
111
112 if (mode & MAY_READ)
113 s[i++] = 'r';
114 if (mode & MAY_WRITE)
115 s[i++] = 'w';
116 if (mode & MAY_EXEC)
117 s[i++] = 'x';
118 if (mode & MAY_APPEND)
119 s[i++] = 'a';
120 if (mode & MAY_TRANSMUTE)
121 s[i++] = 't';
122 if (mode & MAY_LOCK)
123 s[i++] = 'l';
124 if (i == 0)
125 s[i++] = '-';
126 s[i] = '\0';
127}
128#endif
129
130#ifdef CONFIG_SECURITY_SMACK_BRINGUP
131static int smk_bu_note(char *note, struct smack_known *sskp,
132 struct smack_known *oskp, int mode, int rc)
133{
134 char acc[SMK_NUM_ACCESS_TYPE + 1];
135
136 if (rc <= 0)
137 return rc;
138 if (rc > SMACK_UNCONFINED_OBJECT)
139 rc = 0;
140
141 smk_bu_mode(mode, acc);
142 pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
143 sskp->smk_known, oskp->smk_known, acc, note);
144 return 0;
145}
146#else
147#define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
148#endif
149
150#ifdef CONFIG_SECURITY_SMACK_BRINGUP
151static int smk_bu_current(char *note, struct smack_known *oskp,
152 int mode, int rc)
153{
154 struct task_smack *tsp = smack_cred(current_cred());
155 char acc[SMK_NUM_ACCESS_TYPE + 1];
156
157 if (rc <= 0)
158 return rc;
159 if (rc > SMACK_UNCONFINED_OBJECT)
160 rc = 0;
161
162 smk_bu_mode(mode, acc);
163 pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
164 tsp->smk_task->smk_known, oskp->smk_known,
165 acc, current->comm, note);
166 return 0;
167}
168#else
169#define smk_bu_current(note, oskp, mode, RC) (RC)
170#endif
171
172#ifdef CONFIG_SECURITY_SMACK_BRINGUP
173static int smk_bu_task(struct task_struct *otp, int mode, int rc)
174{
175 struct task_smack *tsp = smack_cred(current_cred());
176 struct smack_known *smk_task = smk_of_task_struct_obj(otp);
177 char acc[SMK_NUM_ACCESS_TYPE + 1];
178
179 if (rc <= 0)
180 return rc;
181 if (rc > SMACK_UNCONFINED_OBJECT)
182 rc = 0;
183
184 smk_bu_mode(mode, acc);
185 pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
186 tsp->smk_task->smk_known, smk_task->smk_known, acc,
187 current->comm, otp->comm);
188 return 0;
189}
190#else
191#define smk_bu_task(otp, mode, RC) (RC)
192#endif
193
194#ifdef CONFIG_SECURITY_SMACK_BRINGUP
195static int smk_bu_inode(struct inode *inode, int mode, int rc)
196{
197 struct task_smack *tsp = smack_cred(current_cred());
198 struct inode_smack *isp = smack_inode(inode);
199 char acc[SMK_NUM_ACCESS_TYPE + 1];
200
201 if (isp->smk_flags & SMK_INODE_IMPURE)
202 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
203 inode->i_sb->s_id, inode->i_ino, current->comm);
204
205 if (rc <= 0)
206 return rc;
207 if (rc > SMACK_UNCONFINED_OBJECT)
208 rc = 0;
209 if (rc == SMACK_UNCONFINED_SUBJECT &&
210 (mode & (MAY_WRITE | MAY_APPEND)))
211 isp->smk_flags |= SMK_INODE_IMPURE;
212
213 smk_bu_mode(mode, acc);
214
215 pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
216 tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
217 inode->i_sb->s_id, inode->i_ino, current->comm);
218 return 0;
219}
220#else
221#define smk_bu_inode(inode, mode, RC) (RC)
222#endif
223
224#ifdef CONFIG_SECURITY_SMACK_BRINGUP
225static int smk_bu_file(struct file *file, int mode, int rc)
226{
227 struct task_smack *tsp = smack_cred(current_cred());
228 struct smack_known *sskp = tsp->smk_task;
229 struct inode *inode = file_inode(file);
230 struct inode_smack *isp = smack_inode(inode);
231 char acc[SMK_NUM_ACCESS_TYPE + 1];
232
233 if (isp->smk_flags & SMK_INODE_IMPURE)
234 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
235 inode->i_sb->s_id, inode->i_ino, current->comm);
236
237 if (rc <= 0)
238 return rc;
239 if (rc > SMACK_UNCONFINED_OBJECT)
240 rc = 0;
241
242 smk_bu_mode(mode, acc);
243 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
244 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
245 inode->i_sb->s_id, inode->i_ino, file,
246 current->comm);
247 return 0;
248}
249#else
250#define smk_bu_file(file, mode, RC) (RC)
251#endif
252
253#ifdef CONFIG_SECURITY_SMACK_BRINGUP
254static int smk_bu_credfile(const struct cred *cred, struct file *file,
255 int mode, int rc)
256{
257 struct task_smack *tsp = smack_cred(cred);
258 struct smack_known *sskp = tsp->smk_task;
259 struct inode *inode = file_inode(file);
260 struct inode_smack *isp = smack_inode(inode);
261 char acc[SMK_NUM_ACCESS_TYPE + 1];
262
263 if (isp->smk_flags & SMK_INODE_IMPURE)
264 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
265 inode->i_sb->s_id, inode->i_ino, current->comm);
266
267 if (rc <= 0)
268 return rc;
269 if (rc > SMACK_UNCONFINED_OBJECT)
270 rc = 0;
271
272 smk_bu_mode(mode, acc);
273 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
274 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
275 inode->i_sb->s_id, inode->i_ino, file,
276 current->comm);
277 return 0;
278}
279#else
280#define smk_bu_credfile(cred, file, mode, RC) (RC)
281#endif
282
283/**
284 * smk_fetch - Fetch the smack label from a file.
285 * @name: type of the label (attribute)
286 * @ip: a pointer to the inode
287 * @dp: a pointer to the dentry
288 *
289 * Returns a pointer to the master list entry for the Smack label,
290 * NULL if there was no label to fetch, or an error code.
291 */
292static struct smack_known *smk_fetch(const char *name, struct inode *ip,
293 struct dentry *dp)
294{
295 int rc;
296 char *buffer;
297 struct smack_known *skp = NULL;
298
299 if (!(ip->i_opflags & IOP_XATTR))
300 return ERR_PTR(-EOPNOTSUPP);
301
302 buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS);
303 if (buffer == NULL)
304 return ERR_PTR(-ENOMEM);
305
306 rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
307 if (rc < 0)
308 skp = ERR_PTR(rc);
309 else if (rc == 0)
310 skp = NULL;
311 else
312 skp = smk_import_entry(buffer, rc);
313
314 kfree(buffer);
315
316 return skp;
317}
318
319/**
320 * init_inode_smack - initialize an inode security blob
321 * @inode: inode to extract the info from
322 * @skp: a pointer to the Smack label entry to use in the blob
323 *
324 */
325static void init_inode_smack(struct inode *inode, struct smack_known *skp)
326{
327 struct inode_smack *isp = smack_inode(inode);
328
329 isp->smk_inode = skp;
330 isp->smk_flags = 0;
331}
332
333/**
334 * init_task_smack - initialize a task security blob
335 * @tsp: blob to initialize
336 * @task: a pointer to the Smack label for the running task
337 * @forked: a pointer to the Smack label for the forked task
338 *
339 */
340static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
341 struct smack_known *forked)
342{
343 tsp->smk_task = task;
344 tsp->smk_forked = forked;
345 INIT_LIST_HEAD(&tsp->smk_rules);
346 INIT_LIST_HEAD(&tsp->smk_relabel);
347 mutex_init(&tsp->smk_rules_lock);
348}
349
350/**
351 * smk_copy_rules - copy a rule set
352 * @nhead: new rules header pointer
353 * @ohead: old rules header pointer
354 * @gfp: type of the memory for the allocation
355 *
356 * Returns 0 on success, -ENOMEM on error
357 */
358static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
359 gfp_t gfp)
360{
361 struct smack_rule *nrp;
362 struct smack_rule *orp;
363 int rc = 0;
364
365 list_for_each_entry_rcu(orp, ohead, list) {
366 nrp = kmem_cache_zalloc(smack_rule_cache, gfp);
367 if (nrp == NULL) {
368 rc = -ENOMEM;
369 break;
370 }
371 *nrp = *orp;
372 list_add_rcu(&nrp->list, nhead);
373 }
374 return rc;
375}
376
377/**
378 * smk_copy_relabel - copy smk_relabel labels list
379 * @nhead: new rules header pointer
380 * @ohead: old rules header pointer
381 * @gfp: type of the memory for the allocation
382 *
383 * Returns 0 on success, -ENOMEM on error
384 */
385static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
386 gfp_t gfp)
387{
388 struct smack_known_list_elem *nklep;
389 struct smack_known_list_elem *oklep;
390
391 list_for_each_entry(oklep, ohead, list) {
392 nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
393 if (nklep == NULL) {
394 smk_destroy_label_list(nhead);
395 return -ENOMEM;
396 }
397 nklep->smk_label = oklep->smk_label;
398 list_add(&nklep->list, nhead);
399 }
400
401 return 0;
402}
403
404/**
405 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
406 * @mode: input mode in form of PTRACE_MODE_*
407 *
408 * Returns a converted MAY_* mode usable by smack rules
409 */
410static inline unsigned int smk_ptrace_mode(unsigned int mode)
411{
412 if (mode & PTRACE_MODE_ATTACH)
413 return MAY_READWRITE;
414 if (mode & PTRACE_MODE_READ)
415 return MAY_READ;
416
417 return 0;
418}
419
420/**
421 * smk_ptrace_rule_check - helper for ptrace access
422 * @tracer: tracer process
423 * @tracee_known: label entry of the process that's about to be traced
424 * @mode: ptrace attachment mode (PTRACE_MODE_*)
425 * @func: name of the function that called us, used for audit
426 *
427 * Returns 0 on access granted, -error on error
428 */
429static int smk_ptrace_rule_check(struct task_struct *tracer,
430 struct smack_known *tracee_known,
431 unsigned int mode, const char *func)
432{
433 int rc;
434 struct smk_audit_info ad, *saip = NULL;
435 struct task_smack *tsp;
436 struct smack_known *tracer_known;
437 const struct cred *tracercred;
438
439 if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
440 smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
441 smk_ad_setfield_u_tsk(&ad, tracer);
442 saip = &ad;
443 }
444
445 rcu_read_lock();
446 tracercred = __task_cred(tracer);
447 tsp = smack_cred(tracercred);
448 tracer_known = smk_of_task(tsp);
449
450 if ((mode & PTRACE_MODE_ATTACH) &&
451 (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
452 smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
453 if (tracer_known->smk_known == tracee_known->smk_known)
454 rc = 0;
455 else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
456 rc = -EACCES;
457 else if (smack_privileged_cred(CAP_SYS_PTRACE, tracercred))
458 rc = 0;
459 else
460 rc = -EACCES;
461
462 if (saip)
463 smack_log(tracer_known->smk_known,
464 tracee_known->smk_known,
465 0, rc, saip);
466
467 rcu_read_unlock();
468 return rc;
469 }
470
471 /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
472 rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
473
474 rcu_read_unlock();
475 return rc;
476}
477
478/*
479 * LSM hooks.
480 * We he, that is fun!
481 */
482
483/**
484 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
485 * @ctp: child task pointer
486 * @mode: ptrace attachment mode (PTRACE_MODE_*)
487 *
488 * Returns 0 if access is OK, an error code otherwise
489 *
490 * Do the capability checks.
491 */
492static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
493{
494 struct smack_known *skp;
495
496 skp = smk_of_task_struct_obj(ctp);
497
498 return smk_ptrace_rule_check(current, skp, mode, __func__);
499}
500
501/**
502 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
503 * @ptp: parent task pointer
504 *
505 * Returns 0 if access is OK, an error code otherwise
506 *
507 * Do the capability checks, and require PTRACE_MODE_ATTACH.
508 */
509static int smack_ptrace_traceme(struct task_struct *ptp)
510{
511 struct smack_known *skp;
512
513 skp = smk_of_task(smack_cred(current_cred()));
514
515 return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
516}
517
518/**
519 * smack_syslog - Smack approval on syslog
520 * @typefrom_file: unused
521 *
522 * Returns 0 on success, error code otherwise.
523 */
524static int smack_syslog(int typefrom_file)
525{
526 int rc = 0;
527 struct smack_known *skp = smk_of_current();
528
529 if (smack_privileged(CAP_MAC_OVERRIDE))
530 return 0;
531
532 if (smack_syslog_label != NULL && smack_syslog_label != skp)
533 rc = -EACCES;
534
535 return rc;
536}
537
538/*
539 * Superblock Hooks.
540 */
541
542/**
543 * smack_sb_alloc_security - allocate a superblock blob
544 * @sb: the superblock getting the blob
545 *
546 * Returns 0 on success or -ENOMEM on error.
547 */
548static int smack_sb_alloc_security(struct super_block *sb)
549{
550 struct superblock_smack *sbsp = smack_superblock(sb);
551
552 sbsp->smk_root = &smack_known_floor;
553 sbsp->smk_default = &smack_known_floor;
554 sbsp->smk_floor = &smack_known_floor;
555 sbsp->smk_hat = &smack_known_hat;
556 /*
557 * SMK_SB_INITIALIZED will be zero from kzalloc.
558 */
559
560 return 0;
561}
562
563struct smack_mnt_opts {
564 const char *fsdefault;
565 const char *fsfloor;
566 const char *fshat;
567 const char *fsroot;
568 const char *fstransmute;
569};
570
571static void smack_free_mnt_opts(void *mnt_opts)
572{
573 kfree(mnt_opts);
574}
575
576static int smack_add_opt(int token, const char *s, void **mnt_opts)
577{
578 struct smack_mnt_opts *opts = *mnt_opts;
579 struct smack_known *skp;
580
581 if (!opts) {
582 opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
583 if (!opts)
584 return -ENOMEM;
585 *mnt_opts = opts;
586 }
587 if (!s)
588 return -ENOMEM;
589
590 skp = smk_import_entry(s, 0);
591 if (IS_ERR(skp))
592 return PTR_ERR(skp);
593
594 switch (token) {
595 case Opt_fsdefault:
596 if (opts->fsdefault)
597 goto out_opt_err;
598 opts->fsdefault = skp->smk_known;
599 break;
600 case Opt_fsfloor:
601 if (opts->fsfloor)
602 goto out_opt_err;
603 opts->fsfloor = skp->smk_known;
604 break;
605 case Opt_fshat:
606 if (opts->fshat)
607 goto out_opt_err;
608 opts->fshat = skp->smk_known;
609 break;
610 case Opt_fsroot:
611 if (opts->fsroot)
612 goto out_opt_err;
613 opts->fsroot = skp->smk_known;
614 break;
615 case Opt_fstransmute:
616 if (opts->fstransmute)
617 goto out_opt_err;
618 opts->fstransmute = skp->smk_known;
619 break;
620 }
621 return 0;
622
623out_opt_err:
624 pr_warn("Smack: duplicate mount options\n");
625 return -EINVAL;
626}
627
628/**
629 * smack_fs_context_submount - Initialise security data for a filesystem context
630 * @fc: The filesystem context.
631 * @reference: reference superblock
632 *
633 * Returns 0 on success or -ENOMEM on error.
634 */
635static int smack_fs_context_submount(struct fs_context *fc,
636 struct super_block *reference)
637{
638 struct superblock_smack *sbsp;
639 struct smack_mnt_opts *ctx;
640 struct inode_smack *isp;
641
642 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
643 if (!ctx)
644 return -ENOMEM;
645 fc->security = ctx;
646
647 sbsp = smack_superblock(reference);
648 isp = smack_inode(reference->s_root->d_inode);
649
650 if (sbsp->smk_default) {
651 ctx->fsdefault = kstrdup(sbsp->smk_default->smk_known, GFP_KERNEL);
652 if (!ctx->fsdefault)
653 return -ENOMEM;
654 }
655
656 if (sbsp->smk_floor) {
657 ctx->fsfloor = kstrdup(sbsp->smk_floor->smk_known, GFP_KERNEL);
658 if (!ctx->fsfloor)
659 return -ENOMEM;
660 }
661
662 if (sbsp->smk_hat) {
663 ctx->fshat = kstrdup(sbsp->smk_hat->smk_known, GFP_KERNEL);
664 if (!ctx->fshat)
665 return -ENOMEM;
666 }
667
668 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
669 if (sbsp->smk_root) {
670 ctx->fstransmute = kstrdup(sbsp->smk_root->smk_known, GFP_KERNEL);
671 if (!ctx->fstransmute)
672 return -ENOMEM;
673 }
674 }
675 return 0;
676}
677
678/**
679 * smack_fs_context_dup - Duplicate the security data on fs_context duplication
680 * @fc: The new filesystem context.
681 * @src_fc: The source filesystem context being duplicated.
682 *
683 * Returns 0 on success or -ENOMEM on error.
684 */
685static int smack_fs_context_dup(struct fs_context *fc,
686 struct fs_context *src_fc)
687{
688 struct smack_mnt_opts *dst, *src = src_fc->security;
689
690 if (!src)
691 return 0;
692
693 fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
694 if (!fc->security)
695 return -ENOMEM;
696
697 dst = fc->security;
698 dst->fsdefault = src->fsdefault;
699 dst->fsfloor = src->fsfloor;
700 dst->fshat = src->fshat;
701 dst->fsroot = src->fsroot;
702 dst->fstransmute = src->fstransmute;
703
704 return 0;
705}
706
707static const struct fs_parameter_spec smack_fs_parameters[] = {
708 fsparam_string("smackfsdef", Opt_fsdefault),
709 fsparam_string("smackfsdefault", Opt_fsdefault),
710 fsparam_string("smackfsfloor", Opt_fsfloor),
711 fsparam_string("smackfshat", Opt_fshat),
712 fsparam_string("smackfsroot", Opt_fsroot),
713 fsparam_string("smackfstransmute", Opt_fstransmute),
714 {}
715};
716
717/**
718 * smack_fs_context_parse_param - Parse a single mount parameter
719 * @fc: The new filesystem context being constructed.
720 * @param: The parameter.
721 *
722 * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on
723 * error.
724 */
725static int smack_fs_context_parse_param(struct fs_context *fc,
726 struct fs_parameter *param)
727{
728 struct fs_parse_result result;
729 int opt, rc;
730
731 opt = fs_parse(fc, smack_fs_parameters, param, &result);
732 if (opt < 0)
733 return opt;
734
735 rc = smack_add_opt(opt, param->string, &fc->security);
736 if (!rc)
737 param->string = NULL;
738 return rc;
739}
740
741static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
742{
743 char *from = options, *to = options;
744 bool first = true;
745
746 while (1) {
747 char *next = strchr(from, ',');
748 int token, len, rc;
749 char *arg = NULL;
750
751 if (next)
752 len = next - from;
753 else
754 len = strlen(from);
755
756 token = match_opt_prefix(from, len, &arg);
757 if (token != Opt_error) {
758 arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
759 rc = smack_add_opt(token, arg, mnt_opts);
760 kfree(arg);
761 if (unlikely(rc)) {
762 if (*mnt_opts)
763 smack_free_mnt_opts(*mnt_opts);
764 *mnt_opts = NULL;
765 return rc;
766 }
767 } else {
768 if (!first) { // copy with preceding comma
769 from--;
770 len++;
771 }
772 if (to != from)
773 memmove(to, from, len);
774 to += len;
775 first = false;
776 }
777 if (!from[len])
778 break;
779 from += len + 1;
780 }
781 *to = '\0';
782 return 0;
783}
784
785/**
786 * smack_set_mnt_opts - set Smack specific mount options
787 * @sb: the file system superblock
788 * @mnt_opts: Smack mount options
789 * @kern_flags: mount option from kernel space or user space
790 * @set_kern_flags: where to store converted mount opts
791 *
792 * Returns 0 on success, an error code on failure
793 *
794 * Allow filesystems with binary mount data to explicitly set Smack mount
795 * labels.
796 */
797static int smack_set_mnt_opts(struct super_block *sb,
798 void *mnt_opts,
799 unsigned long kern_flags,
800 unsigned long *set_kern_flags)
801{
802 struct dentry *root = sb->s_root;
803 struct inode *inode = d_backing_inode(root);
804 struct superblock_smack *sp = smack_superblock(sb);
805 struct inode_smack *isp;
806 struct smack_known *skp;
807 struct smack_mnt_opts *opts = mnt_opts;
808 bool transmute = false;
809
810 if (sp->smk_flags & SMK_SB_INITIALIZED)
811 return 0;
812
813 if (!smack_privileged(CAP_MAC_ADMIN)) {
814 /*
815 * Unprivileged mounts don't get to specify Smack values.
816 */
817 if (opts)
818 return -EPERM;
819 /*
820 * Unprivileged mounts get root and default from the caller.
821 */
822 skp = smk_of_current();
823 sp->smk_root = skp;
824 sp->smk_default = skp;
825 /*
826 * For a handful of fs types with no user-controlled
827 * backing store it's okay to trust security labels
828 * in the filesystem. The rest are untrusted.
829 */
830 if (sb->s_user_ns != &init_user_ns &&
831 sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
832 sb->s_magic != RAMFS_MAGIC) {
833 transmute = true;
834 sp->smk_flags |= SMK_SB_UNTRUSTED;
835 }
836 }
837
838 sp->smk_flags |= SMK_SB_INITIALIZED;
839
840 if (opts) {
841 if (opts->fsdefault) {
842 skp = smk_import_entry(opts->fsdefault, 0);
843 if (IS_ERR(skp))
844 return PTR_ERR(skp);
845 sp->smk_default = skp;
846 }
847 if (opts->fsfloor) {
848 skp = smk_import_entry(opts->fsfloor, 0);
849 if (IS_ERR(skp))
850 return PTR_ERR(skp);
851 sp->smk_floor = skp;
852 }
853 if (opts->fshat) {
854 skp = smk_import_entry(opts->fshat, 0);
855 if (IS_ERR(skp))
856 return PTR_ERR(skp);
857 sp->smk_hat = skp;
858 }
859 if (opts->fsroot) {
860 skp = smk_import_entry(opts->fsroot, 0);
861 if (IS_ERR(skp))
862 return PTR_ERR(skp);
863 sp->smk_root = skp;
864 }
865 if (opts->fstransmute) {
866 skp = smk_import_entry(opts->fstransmute, 0);
867 if (IS_ERR(skp))
868 return PTR_ERR(skp);
869 sp->smk_root = skp;
870 transmute = true;
871 }
872 }
873
874 /*
875 * Initialize the root inode.
876 */
877 init_inode_smack(inode, sp->smk_root);
878
879 if (transmute) {
880 isp = smack_inode(inode);
881 isp->smk_flags |= SMK_INODE_TRANSMUTE;
882 }
883
884 return 0;
885}
886
887/**
888 * smack_sb_statfs - Smack check on statfs
889 * @dentry: identifies the file system in question
890 *
891 * Returns 0 if current can read the floor of the filesystem,
892 * and error code otherwise
893 */
894static int smack_sb_statfs(struct dentry *dentry)
895{
896 struct superblock_smack *sbp = smack_superblock(dentry->d_sb);
897 int rc;
898 struct smk_audit_info ad;
899
900 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
901 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
902
903 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
904 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
905 return rc;
906}
907
908/*
909 * BPRM hooks
910 */
911
912/**
913 * smack_bprm_creds_for_exec - Update bprm->cred if needed for exec
914 * @bprm: the exec information
915 *
916 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
917 */
918static int smack_bprm_creds_for_exec(struct linux_binprm *bprm)
919{
920 struct inode *inode = file_inode(bprm->file);
921 struct task_smack *bsp = smack_cred(bprm->cred);
922 struct inode_smack *isp;
923 struct superblock_smack *sbsp;
924 int rc;
925
926 isp = smack_inode(inode);
927 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
928 return 0;
929
930 sbsp = smack_superblock(inode->i_sb);
931 if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
932 isp->smk_task != sbsp->smk_root)
933 return 0;
934
935 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
936 struct task_struct *tracer;
937 rc = 0;
938
939 rcu_read_lock();
940 tracer = ptrace_parent(current);
941 if (likely(tracer != NULL))
942 rc = smk_ptrace_rule_check(tracer,
943 isp->smk_task,
944 PTRACE_MODE_ATTACH,
945 __func__);
946 rcu_read_unlock();
947
948 if (rc != 0)
949 return rc;
950 }
951 if (bprm->unsafe & ~LSM_UNSAFE_PTRACE)
952 return -EPERM;
953
954 bsp->smk_task = isp->smk_task;
955 bprm->per_clear |= PER_CLEAR_ON_SETID;
956
957 /* Decide if this is a secure exec. */
958 if (bsp->smk_task != bsp->smk_forked)
959 bprm->secureexec = 1;
960
961 return 0;
962}
963
964/*
965 * Inode hooks
966 */
967
968/**
969 * smack_inode_alloc_security - allocate an inode blob
970 * @inode: the inode in need of a blob
971 *
972 * Returns 0
973 */
974static int smack_inode_alloc_security(struct inode *inode)
975{
976 struct smack_known *skp = smk_of_current();
977
978 init_inode_smack(inode, skp);
979 return 0;
980}
981
982/**
983 * smack_inode_init_security - copy out the smack from an inode
984 * @inode: the newly created inode
985 * @dir: containing directory object
986 * @qstr: unused
987 * @xattrs: where to put the attributes
988 * @xattr_count: current number of LSM-provided xattrs (updated)
989 *
990 * Returns 0 if it all works out, -ENOMEM if there's no memory
991 */
992static int smack_inode_init_security(struct inode *inode, struct inode *dir,
993 const struct qstr *qstr,
994 struct xattr *xattrs, int *xattr_count)
995{
996 struct task_smack *tsp = smack_cred(current_cred());
997 struct inode_smack *issp = smack_inode(inode);
998 struct smack_known *skp = smk_of_task(tsp);
999 struct smack_known *isp = smk_of_inode(inode);
1000 struct smack_known *dsp = smk_of_inode(dir);
1001 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
1002 int may;
1003
1004 /*
1005 * If equal, transmuting already occurred in
1006 * smack_dentry_create_files_as(). No need to check again.
1007 */
1008 if (tsp->smk_task != tsp->smk_transmuted) {
1009 rcu_read_lock();
1010 may = smk_access_entry(skp->smk_known, dsp->smk_known,
1011 &skp->smk_rules);
1012 rcu_read_unlock();
1013 }
1014
1015 /*
1016 * In addition to having smk_task equal to smk_transmuted,
1017 * if the access rule allows transmutation and the directory
1018 * requests transmutation then by all means transmute.
1019 * Mark the inode as changed.
1020 */
1021 if ((tsp->smk_task == tsp->smk_transmuted) ||
1022 (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
1023 smk_inode_transmutable(dir))) {
1024 struct xattr *xattr_transmute;
1025
1026 /*
1027 * The caller of smack_dentry_create_files_as()
1028 * should have overridden the current cred, so the
1029 * inode label was already set correctly in
1030 * smack_inode_alloc_security().
1031 */
1032 if (tsp->smk_task != tsp->smk_transmuted)
1033 isp = issp->smk_inode = dsp;
1034
1035 issp->smk_flags |= SMK_INODE_TRANSMUTE;
1036 xattr_transmute = lsm_get_xattr_slot(xattrs,
1037 xattr_count);
1038 if (xattr_transmute) {
1039 xattr_transmute->value = kmemdup(TRANS_TRUE,
1040 TRANS_TRUE_SIZE,
1041 GFP_NOFS);
1042 if (!xattr_transmute->value)
1043 return -ENOMEM;
1044
1045 xattr_transmute->value_len = TRANS_TRUE_SIZE;
1046 xattr_transmute->name = XATTR_SMACK_TRANSMUTE;
1047 }
1048 }
1049
1050 issp->smk_flags |= SMK_INODE_INSTANT;
1051
1052 if (xattr) {
1053 xattr->value = kstrdup(isp->smk_known, GFP_NOFS);
1054 if (!xattr->value)
1055 return -ENOMEM;
1056
1057 xattr->value_len = strlen(isp->smk_known);
1058 xattr->name = XATTR_SMACK_SUFFIX;
1059 }
1060
1061 return 0;
1062}
1063
1064/**
1065 * smack_inode_link - Smack check on link
1066 * @old_dentry: the existing object
1067 * @dir: unused
1068 * @new_dentry: the new object
1069 *
1070 * Returns 0 if access is permitted, an error code otherwise
1071 */
1072static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1073 struct dentry *new_dentry)
1074{
1075 struct smack_known *isp;
1076 struct smk_audit_info ad;
1077 int rc;
1078
1079 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1080 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1081
1082 isp = smk_of_inode(d_backing_inode(old_dentry));
1083 rc = smk_curacc(isp, MAY_WRITE, &ad);
1084 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1085
1086 if (rc == 0 && d_is_positive(new_dentry)) {
1087 isp = smk_of_inode(d_backing_inode(new_dentry));
1088 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1089 rc = smk_curacc(isp, MAY_WRITE, &ad);
1090 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1091 }
1092
1093 return rc;
1094}
1095
1096/**
1097 * smack_inode_unlink - Smack check on inode deletion
1098 * @dir: containing directory object
1099 * @dentry: file to unlink
1100 *
1101 * Returns 0 if current can write the containing directory
1102 * and the object, error code otherwise
1103 */
1104static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1105{
1106 struct inode *ip = d_backing_inode(dentry);
1107 struct smk_audit_info ad;
1108 int rc;
1109
1110 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1111 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1112
1113 /*
1114 * You need write access to the thing you're unlinking
1115 */
1116 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1117 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1118 if (rc == 0) {
1119 /*
1120 * You also need write access to the containing directory
1121 */
1122 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1123 smk_ad_setfield_u_fs_inode(&ad, dir);
1124 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1125 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1126 }
1127 return rc;
1128}
1129
1130/**
1131 * smack_inode_rmdir - Smack check on directory deletion
1132 * @dir: containing directory object
1133 * @dentry: directory to unlink
1134 *
1135 * Returns 0 if current can write the containing directory
1136 * and the directory, error code otherwise
1137 */
1138static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1139{
1140 struct smk_audit_info ad;
1141 int rc;
1142
1143 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1144 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1145
1146 /*
1147 * You need write access to the thing you're removing
1148 */
1149 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1150 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1151 if (rc == 0) {
1152 /*
1153 * You also need write access to the containing directory
1154 */
1155 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1156 smk_ad_setfield_u_fs_inode(&ad, dir);
1157 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1158 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1159 }
1160
1161 return rc;
1162}
1163
1164/**
1165 * smack_inode_rename - Smack check on rename
1166 * @old_inode: unused
1167 * @old_dentry: the old object
1168 * @new_inode: unused
1169 * @new_dentry: the new object
1170 *
1171 * Read and write access is required on both the old and
1172 * new directories.
1173 *
1174 * Returns 0 if access is permitted, an error code otherwise
1175 */
1176static int smack_inode_rename(struct inode *old_inode,
1177 struct dentry *old_dentry,
1178 struct inode *new_inode,
1179 struct dentry *new_dentry)
1180{
1181 int rc;
1182 struct smack_known *isp;
1183 struct smk_audit_info ad;
1184
1185 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1186 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1187
1188 isp = smk_of_inode(d_backing_inode(old_dentry));
1189 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1190 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1191
1192 if (rc == 0 && d_is_positive(new_dentry)) {
1193 isp = smk_of_inode(d_backing_inode(new_dentry));
1194 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1195 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1196 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1197 }
1198 return rc;
1199}
1200
1201/**
1202 * smack_inode_permission - Smack version of permission()
1203 * @inode: the inode in question
1204 * @mask: the access requested
1205 *
1206 * This is the important Smack hook.
1207 *
1208 * Returns 0 if access is permitted, an error code otherwise
1209 */
1210static int smack_inode_permission(struct inode *inode, int mask)
1211{
1212 struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
1213 struct smk_audit_info ad;
1214 int no_block = mask & MAY_NOT_BLOCK;
1215 int rc;
1216
1217 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1218 /*
1219 * No permission to check. Existence test. Yup, it's there.
1220 */
1221 if (mask == 0)
1222 return 0;
1223
1224 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
1225 if (smk_of_inode(inode) != sbsp->smk_root)
1226 return -EACCES;
1227 }
1228
1229 /* May be droppable after audit */
1230 if (no_block)
1231 return -ECHILD;
1232 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1233 smk_ad_setfield_u_fs_inode(&ad, inode);
1234 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1235 rc = smk_bu_inode(inode, mask, rc);
1236 return rc;
1237}
1238
1239/**
1240 * smack_inode_setattr - Smack check for setting attributes
1241 * @idmap: idmap of the mount
1242 * @dentry: the object
1243 * @iattr: for the force flag
1244 *
1245 * Returns 0 if access is permitted, an error code otherwise
1246 */
1247static int smack_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
1248 struct iattr *iattr)
1249{
1250 struct smk_audit_info ad;
1251 int rc;
1252
1253 /*
1254 * Need to allow for clearing the setuid bit.
1255 */
1256 if (iattr->ia_valid & ATTR_FORCE)
1257 return 0;
1258 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1259 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1260
1261 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1262 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1263 return rc;
1264}
1265
1266/**
1267 * smack_inode_getattr - Smack check for getting attributes
1268 * @path: path to extract the info from
1269 *
1270 * Returns 0 if access is permitted, an error code otherwise
1271 */
1272static int smack_inode_getattr(const struct path *path)
1273{
1274 struct smk_audit_info ad;
1275 struct inode *inode = d_backing_inode(path->dentry);
1276 int rc;
1277
1278 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1279 smk_ad_setfield_u_fs_path(&ad, *path);
1280 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1281 rc = smk_bu_inode(inode, MAY_READ, rc);
1282 return rc;
1283}
1284
1285/**
1286 * smack_inode_setxattr - Smack check for setting xattrs
1287 * @idmap: idmap of the mount
1288 * @dentry: the object
1289 * @name: name of the attribute
1290 * @value: value of the attribute
1291 * @size: size of the value
1292 * @flags: unused
1293 *
1294 * This protects the Smack attribute explicitly.
1295 *
1296 * Returns 0 if access is permitted, an error code otherwise
1297 */
1298static int smack_inode_setxattr(struct mnt_idmap *idmap,
1299 struct dentry *dentry, const char *name,
1300 const void *value, size_t size, int flags)
1301{
1302 struct smk_audit_info ad;
1303 struct smack_known *skp;
1304 int check_priv = 0;
1305 int check_import = 0;
1306 int check_star = 0;
1307 int rc = 0;
1308
1309 /*
1310 * Check label validity here so import won't fail in post_setxattr
1311 */
1312 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1313 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1314 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1315 check_priv = 1;
1316 check_import = 1;
1317 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1318 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1319 check_priv = 1;
1320 check_import = 1;
1321 check_star = 1;
1322 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1323 check_priv = 1;
1324 if (!S_ISDIR(d_backing_inode(dentry)->i_mode) ||
1325 size != TRANS_TRUE_SIZE ||
1326 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1327 rc = -EINVAL;
1328 } else
1329 rc = cap_inode_setxattr(dentry, name, value, size, flags);
1330
1331 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1332 rc = -EPERM;
1333
1334 if (rc == 0 && check_import) {
1335 skp = size ? smk_import_entry(value, size) : NULL;
1336 if (IS_ERR(skp))
1337 rc = PTR_ERR(skp);
1338 else if (skp == NULL || (check_star &&
1339 (skp == &smack_known_star || skp == &smack_known_web)))
1340 rc = -EINVAL;
1341 }
1342
1343 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1344 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1345
1346 if (rc == 0) {
1347 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1348 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1349 }
1350
1351 return rc;
1352}
1353
1354/**
1355 * smack_inode_post_setxattr - Apply the Smack update approved above
1356 * @dentry: object
1357 * @name: attribute name
1358 * @value: attribute value
1359 * @size: attribute size
1360 * @flags: unused
1361 *
1362 * Set the pointer in the inode blob to the entry found
1363 * in the master label list.
1364 */
1365static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1366 const void *value, size_t size, int flags)
1367{
1368 struct smack_known *skp;
1369 struct inode_smack *isp = smack_inode(d_backing_inode(dentry));
1370
1371 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1372 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1373 return;
1374 }
1375
1376 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1377 skp = smk_import_entry(value, size);
1378 if (!IS_ERR(skp))
1379 isp->smk_inode = skp;
1380 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1381 skp = smk_import_entry(value, size);
1382 if (!IS_ERR(skp))
1383 isp->smk_task = skp;
1384 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1385 skp = smk_import_entry(value, size);
1386 if (!IS_ERR(skp))
1387 isp->smk_mmap = skp;
1388 }
1389
1390 return;
1391}
1392
1393/**
1394 * smack_inode_getxattr - Smack check on getxattr
1395 * @dentry: the object
1396 * @name: unused
1397 *
1398 * Returns 0 if access is permitted, an error code otherwise
1399 */
1400static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1401{
1402 struct smk_audit_info ad;
1403 int rc;
1404
1405 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1406 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1407
1408 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1409 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1410 return rc;
1411}
1412
1413/**
1414 * smack_inode_removexattr - Smack check on removexattr
1415 * @idmap: idmap of the mount
1416 * @dentry: the object
1417 * @name: name of the attribute
1418 *
1419 * Removing the Smack attribute requires CAP_MAC_ADMIN
1420 *
1421 * Returns 0 if access is permitted, an error code otherwise
1422 */
1423static int smack_inode_removexattr(struct mnt_idmap *idmap,
1424 struct dentry *dentry, const char *name)
1425{
1426 struct inode_smack *isp;
1427 struct smk_audit_info ad;
1428 int rc = 0;
1429
1430 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1431 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1432 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1433 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1434 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1435 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1436 if (!smack_privileged(CAP_MAC_ADMIN))
1437 rc = -EPERM;
1438 } else
1439 rc = cap_inode_removexattr(idmap, dentry, name);
1440
1441 if (rc != 0)
1442 return rc;
1443
1444 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1445 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1446
1447 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1448 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1449 if (rc != 0)
1450 return rc;
1451
1452 isp = smack_inode(d_backing_inode(dentry));
1453 /*
1454 * Don't do anything special for these.
1455 * XATTR_NAME_SMACKIPIN
1456 * XATTR_NAME_SMACKIPOUT
1457 */
1458 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1459 struct super_block *sbp = dentry->d_sb;
1460 struct superblock_smack *sbsp = smack_superblock(sbp);
1461
1462 isp->smk_inode = sbsp->smk_default;
1463 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1464 isp->smk_task = NULL;
1465 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1466 isp->smk_mmap = NULL;
1467 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1468 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1469
1470 return 0;
1471}
1472
1473/**
1474 * smack_inode_set_acl - Smack check for setting posix acls
1475 * @idmap: idmap of the mnt this request came from
1476 * @dentry: the object
1477 * @acl_name: name of the posix acl
1478 * @kacl: the posix acls
1479 *
1480 * Returns 0 if access is permitted, an error code otherwise
1481 */
1482static int smack_inode_set_acl(struct mnt_idmap *idmap,
1483 struct dentry *dentry, const char *acl_name,
1484 struct posix_acl *kacl)
1485{
1486 struct smk_audit_info ad;
1487 int rc;
1488
1489 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1490 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1491
1492 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1493 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1494 return rc;
1495}
1496
1497/**
1498 * smack_inode_get_acl - Smack check for getting posix acls
1499 * @idmap: idmap of the mnt this request came from
1500 * @dentry: the object
1501 * @acl_name: name of the posix acl
1502 *
1503 * Returns 0 if access is permitted, an error code otherwise
1504 */
1505static int smack_inode_get_acl(struct mnt_idmap *idmap,
1506 struct dentry *dentry, const char *acl_name)
1507{
1508 struct smk_audit_info ad;
1509 int rc;
1510
1511 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1512 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1513
1514 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1515 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1516 return rc;
1517}
1518
1519/**
1520 * smack_inode_remove_acl - Smack check for getting posix acls
1521 * @idmap: idmap of the mnt this request came from
1522 * @dentry: the object
1523 * @acl_name: name of the posix acl
1524 *
1525 * Returns 0 if access is permitted, an error code otherwise
1526 */
1527static int smack_inode_remove_acl(struct mnt_idmap *idmap,
1528 struct dentry *dentry, const char *acl_name)
1529{
1530 struct smk_audit_info ad;
1531 int rc;
1532
1533 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1534 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1535
1536 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1537 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1538 return rc;
1539}
1540
1541/**
1542 * smack_inode_getsecurity - get smack xattrs
1543 * @idmap: idmap of the mount
1544 * @inode: the object
1545 * @name: attribute name
1546 * @buffer: where to put the result
1547 * @alloc: duplicate memory
1548 *
1549 * Returns the size of the attribute or an error code
1550 */
1551static int smack_inode_getsecurity(struct mnt_idmap *idmap,
1552 struct inode *inode, const char *name,
1553 void **buffer, bool alloc)
1554{
1555 struct socket_smack *ssp;
1556 struct socket *sock;
1557 struct super_block *sbp;
1558 struct inode *ip = inode;
1559 struct smack_known *isp;
1560 struct inode_smack *ispp;
1561 size_t label_len;
1562 char *label = NULL;
1563
1564 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1565 isp = smk_of_inode(inode);
1566 } else if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
1567 ispp = smack_inode(inode);
1568 if (ispp->smk_flags & SMK_INODE_TRANSMUTE)
1569 label = TRANS_TRUE;
1570 else
1571 label = "";
1572 } else {
1573 /*
1574 * The rest of the Smack xattrs are only on sockets.
1575 */
1576 sbp = ip->i_sb;
1577 if (sbp->s_magic != SOCKFS_MAGIC)
1578 return -EOPNOTSUPP;
1579
1580 sock = SOCKET_I(ip);
1581 if (sock == NULL || sock->sk == NULL)
1582 return -EOPNOTSUPP;
1583
1584 ssp = sock->sk->sk_security;
1585
1586 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1587 isp = ssp->smk_in;
1588 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1589 isp = ssp->smk_out;
1590 else
1591 return -EOPNOTSUPP;
1592 }
1593
1594 if (!label)
1595 label = isp->smk_known;
1596
1597 label_len = strlen(label);
1598
1599 if (alloc) {
1600 *buffer = kstrdup(label, GFP_KERNEL);
1601 if (*buffer == NULL)
1602 return -ENOMEM;
1603 }
1604
1605 return label_len;
1606}
1607
1608
1609/**
1610 * smack_inode_listsecurity - list the Smack attributes
1611 * @inode: the object
1612 * @buffer: where they go
1613 * @buffer_size: size of buffer
1614 */
1615static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1616 size_t buffer_size)
1617{
1618 int len = sizeof(XATTR_NAME_SMACK);
1619
1620 if (buffer != NULL && len <= buffer_size)
1621 memcpy(buffer, XATTR_NAME_SMACK, len);
1622
1623 return len;
1624}
1625
1626/**
1627 * smack_inode_getsecid - Extract inode's security id
1628 * @inode: inode to extract the info from
1629 * @secid: where result will be saved
1630 */
1631static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1632{
1633 struct smack_known *skp = smk_of_inode(inode);
1634
1635 *secid = skp->smk_secid;
1636}
1637
1638/*
1639 * File Hooks
1640 */
1641
1642/*
1643 * There is no smack_file_permission hook
1644 *
1645 * Should access checks be done on each read or write?
1646 * UNICOS and SELinux say yes.
1647 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1648 *
1649 * I'll say no for now. Smack does not do the frequent
1650 * label changing that SELinux does.
1651 */
1652
1653/**
1654 * smack_file_alloc_security - assign a file security blob
1655 * @file: the object
1656 *
1657 * The security blob for a file is a pointer to the master
1658 * label list, so no allocation is done.
1659 *
1660 * f_security is the owner security information. It
1661 * isn't used on file access checks, it's for send_sigio.
1662 *
1663 * Returns 0
1664 */
1665static int smack_file_alloc_security(struct file *file)
1666{
1667 struct smack_known **blob = smack_file(file);
1668
1669 *blob = smk_of_current();
1670 return 0;
1671}
1672
1673/**
1674 * smack_file_ioctl - Smack check on ioctls
1675 * @file: the object
1676 * @cmd: what to do
1677 * @arg: unused
1678 *
1679 * Relies heavily on the correct use of the ioctl command conventions.
1680 *
1681 * Returns 0 if allowed, error code otherwise
1682 */
1683static int smack_file_ioctl(struct file *file, unsigned int cmd,
1684 unsigned long arg)
1685{
1686 int rc = 0;
1687 struct smk_audit_info ad;
1688 struct inode *inode = file_inode(file);
1689
1690 if (unlikely(IS_PRIVATE(inode)))
1691 return 0;
1692
1693 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1694 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1695
1696 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1697 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1698 rc = smk_bu_file(file, MAY_WRITE, rc);
1699 }
1700
1701 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1702 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1703 rc = smk_bu_file(file, MAY_READ, rc);
1704 }
1705
1706 return rc;
1707}
1708
1709/**
1710 * smack_file_lock - Smack check on file locking
1711 * @file: the object
1712 * @cmd: unused
1713 *
1714 * Returns 0 if current has lock access, error code otherwise
1715 */
1716static int smack_file_lock(struct file *file, unsigned int cmd)
1717{
1718 struct smk_audit_info ad;
1719 int rc;
1720 struct inode *inode = file_inode(file);
1721
1722 if (unlikely(IS_PRIVATE(inode)))
1723 return 0;
1724
1725 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1726 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1727 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1728 rc = smk_bu_file(file, MAY_LOCK, rc);
1729 return rc;
1730}
1731
1732/**
1733 * smack_file_fcntl - Smack check on fcntl
1734 * @file: the object
1735 * @cmd: what action to check
1736 * @arg: unused
1737 *
1738 * Generally these operations are harmless.
1739 * File locking operations present an obvious mechanism
1740 * for passing information, so they require write access.
1741 *
1742 * Returns 0 if current has access, error code otherwise
1743 */
1744static int smack_file_fcntl(struct file *file, unsigned int cmd,
1745 unsigned long arg)
1746{
1747 struct smk_audit_info ad;
1748 int rc = 0;
1749 struct inode *inode = file_inode(file);
1750
1751 if (unlikely(IS_PRIVATE(inode)))
1752 return 0;
1753
1754 switch (cmd) {
1755 case F_GETLK:
1756 break;
1757 case F_SETLK:
1758 case F_SETLKW:
1759 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1760 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1761 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1762 rc = smk_bu_file(file, MAY_LOCK, rc);
1763 break;
1764 case F_SETOWN:
1765 case F_SETSIG:
1766 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1767 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1768 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1769 rc = smk_bu_file(file, MAY_WRITE, rc);
1770 break;
1771 default:
1772 break;
1773 }
1774
1775 return rc;
1776}
1777
1778/**
1779 * smack_mmap_file - Check permissions for a mmap operation.
1780 * @file: contains the file structure for file to map (may be NULL).
1781 * @reqprot: contains the protection requested by the application.
1782 * @prot: contains the protection that will be applied by the kernel.
1783 * @flags: contains the operational flags.
1784 *
1785 * The @file may be NULL, e.g. if mapping anonymous memory.
1786 *
1787 * Return 0 if permission is granted.
1788 */
1789static int smack_mmap_file(struct file *file,
1790 unsigned long reqprot, unsigned long prot,
1791 unsigned long flags)
1792{
1793 struct smack_known *skp;
1794 struct smack_known *mkp;
1795 struct smack_rule *srp;
1796 struct task_smack *tsp;
1797 struct smack_known *okp;
1798 struct inode_smack *isp;
1799 struct superblock_smack *sbsp;
1800 int may;
1801 int mmay;
1802 int tmay;
1803 int rc;
1804
1805 if (file == NULL)
1806 return 0;
1807
1808 if (unlikely(IS_PRIVATE(file_inode(file))))
1809 return 0;
1810
1811 isp = smack_inode(file_inode(file));
1812 if (isp->smk_mmap == NULL)
1813 return 0;
1814 sbsp = smack_superblock(file_inode(file)->i_sb);
1815 if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
1816 isp->smk_mmap != sbsp->smk_root)
1817 return -EACCES;
1818 mkp = isp->smk_mmap;
1819
1820 tsp = smack_cred(current_cred());
1821 skp = smk_of_current();
1822 rc = 0;
1823
1824 rcu_read_lock();
1825 /*
1826 * For each Smack rule associated with the subject
1827 * label verify that the SMACK64MMAP also has access
1828 * to that rule's object label.
1829 */
1830 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1831 okp = srp->smk_object;
1832 /*
1833 * Matching labels always allows access.
1834 */
1835 if (mkp->smk_known == okp->smk_known)
1836 continue;
1837 /*
1838 * If there is a matching local rule take
1839 * that into account as well.
1840 */
1841 may = smk_access_entry(srp->smk_subject->smk_known,
1842 okp->smk_known,
1843 &tsp->smk_rules);
1844 if (may == -ENOENT)
1845 may = srp->smk_access;
1846 else
1847 may &= srp->smk_access;
1848 /*
1849 * If may is zero the SMACK64MMAP subject can't
1850 * possibly have less access.
1851 */
1852 if (may == 0)
1853 continue;
1854
1855 /*
1856 * Fetch the global list entry.
1857 * If there isn't one a SMACK64MMAP subject
1858 * can't have as much access as current.
1859 */
1860 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1861 &mkp->smk_rules);
1862 if (mmay == -ENOENT) {
1863 rc = -EACCES;
1864 break;
1865 }
1866 /*
1867 * If there is a local entry it modifies the
1868 * potential access, too.
1869 */
1870 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1871 &tsp->smk_rules);
1872 if (tmay != -ENOENT)
1873 mmay &= tmay;
1874
1875 /*
1876 * If there is any access available to current that is
1877 * not available to a SMACK64MMAP subject
1878 * deny access.
1879 */
1880 if ((may | mmay) != mmay) {
1881 rc = -EACCES;
1882 break;
1883 }
1884 }
1885
1886 rcu_read_unlock();
1887
1888 return rc;
1889}
1890
1891/**
1892 * smack_file_set_fowner - set the file security blob value
1893 * @file: object in question
1894 *
1895 */
1896static void smack_file_set_fowner(struct file *file)
1897{
1898 struct smack_known **blob = smack_file(file);
1899
1900 *blob = smk_of_current();
1901}
1902
1903/**
1904 * smack_file_send_sigiotask - Smack on sigio
1905 * @tsk: The target task
1906 * @fown: the object the signal come from
1907 * @signum: unused
1908 *
1909 * Allow a privileged task to get signals even if it shouldn't
1910 *
1911 * Returns 0 if a subject with the object's smack could
1912 * write to the task, an error code otherwise.
1913 */
1914static int smack_file_send_sigiotask(struct task_struct *tsk,
1915 struct fown_struct *fown, int signum)
1916{
1917 struct smack_known **blob;
1918 struct smack_known *skp;
1919 struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
1920 const struct cred *tcred;
1921 struct file *file;
1922 int rc;
1923 struct smk_audit_info ad;
1924
1925 /*
1926 * struct fown_struct is never outside the context of a struct file
1927 */
1928 file = container_of(fown, struct file, f_owner);
1929
1930 /* we don't log here as rc can be overriden */
1931 blob = smack_file(file);
1932 skp = *blob;
1933 rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
1934 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1935
1936 rcu_read_lock();
1937 tcred = __task_cred(tsk);
1938 if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred))
1939 rc = 0;
1940 rcu_read_unlock();
1941
1942 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1943 smk_ad_setfield_u_tsk(&ad, tsk);
1944 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1945 return rc;
1946}
1947
1948/**
1949 * smack_file_receive - Smack file receive check
1950 * @file: the object
1951 *
1952 * Returns 0 if current has access, error code otherwise
1953 */
1954static int smack_file_receive(struct file *file)
1955{
1956 int rc;
1957 int may = 0;
1958 struct smk_audit_info ad;
1959 struct inode *inode = file_inode(file);
1960 struct socket *sock;
1961 struct task_smack *tsp;
1962 struct socket_smack *ssp;
1963
1964 if (unlikely(IS_PRIVATE(inode)))
1965 return 0;
1966
1967 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1968 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1969
1970 if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
1971 sock = SOCKET_I(inode);
1972 ssp = sock->sk->sk_security;
1973 tsp = smack_cred(current_cred());
1974 /*
1975 * If the receiving process can't write to the
1976 * passed socket or if the passed socket can't
1977 * write to the receiving process don't accept
1978 * the passed socket.
1979 */
1980 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
1981 rc = smk_bu_file(file, may, rc);
1982 if (rc < 0)
1983 return rc;
1984 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
1985 rc = smk_bu_file(file, may, rc);
1986 return rc;
1987 }
1988 /*
1989 * This code relies on bitmasks.
1990 */
1991 if (file->f_mode & FMODE_READ)
1992 may = MAY_READ;
1993 if (file->f_mode & FMODE_WRITE)
1994 may |= MAY_WRITE;
1995
1996 rc = smk_curacc(smk_of_inode(inode), may, &ad);
1997 rc = smk_bu_file(file, may, rc);
1998 return rc;
1999}
2000
2001/**
2002 * smack_file_open - Smack dentry open processing
2003 * @file: the object
2004 *
2005 * Set the security blob in the file structure.
2006 * Allow the open only if the task has read access. There are
2007 * many read operations (e.g. fstat) that you can do with an
2008 * fd even if you have the file open write-only.
2009 *
2010 * Returns 0 if current has access, error code otherwise
2011 */
2012static int smack_file_open(struct file *file)
2013{
2014 struct task_smack *tsp = smack_cred(file->f_cred);
2015 struct inode *inode = file_inode(file);
2016 struct smk_audit_info ad;
2017 int rc;
2018
2019 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
2020 smk_ad_setfield_u_fs_path(&ad, file->f_path);
2021 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
2022 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
2023
2024 return rc;
2025}
2026
2027/*
2028 * Task hooks
2029 */
2030
2031/**
2032 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
2033 * @cred: the new credentials
2034 * @gfp: the atomicity of any memory allocations
2035 *
2036 * Prepare a blank set of credentials for modification. This must allocate all
2037 * the memory the LSM module might require such that cred_transfer() can
2038 * complete without error.
2039 */
2040static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
2041{
2042 init_task_smack(smack_cred(cred), NULL, NULL);
2043 return 0;
2044}
2045
2046
2047/**
2048 * smack_cred_free - "free" task-level security credentials
2049 * @cred: the credentials in question
2050 *
2051 */
2052static void smack_cred_free(struct cred *cred)
2053{
2054 struct task_smack *tsp = smack_cred(cred);
2055 struct smack_rule *rp;
2056 struct list_head *l;
2057 struct list_head *n;
2058
2059 smk_destroy_label_list(&tsp->smk_relabel);
2060
2061 list_for_each_safe(l, n, &tsp->smk_rules) {
2062 rp = list_entry(l, struct smack_rule, list);
2063 list_del(&rp->list);
2064 kmem_cache_free(smack_rule_cache, rp);
2065 }
2066}
2067
2068/**
2069 * smack_cred_prepare - prepare new set of credentials for modification
2070 * @new: the new credentials
2071 * @old: the original credentials
2072 * @gfp: the atomicity of any memory allocations
2073 *
2074 * Prepare a new set of credentials for modification.
2075 */
2076static int smack_cred_prepare(struct cred *new, const struct cred *old,
2077 gfp_t gfp)
2078{
2079 struct task_smack *old_tsp = smack_cred(old);
2080 struct task_smack *new_tsp = smack_cred(new);
2081 int rc;
2082
2083 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
2084
2085 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
2086 if (rc != 0)
2087 return rc;
2088
2089 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2090 gfp);
2091 return rc;
2092}
2093
2094/**
2095 * smack_cred_transfer - Transfer the old credentials to the new credentials
2096 * @new: the new credentials
2097 * @old: the original credentials
2098 *
2099 * Fill in a set of blank credentials from another set of credentials.
2100 */
2101static void smack_cred_transfer(struct cred *new, const struct cred *old)
2102{
2103 struct task_smack *old_tsp = smack_cred(old);
2104 struct task_smack *new_tsp = smack_cred(new);
2105
2106 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
2107}
2108
2109/**
2110 * smack_cred_getsecid - get the secid corresponding to a creds structure
2111 * @cred: the object creds
2112 * @secid: where to put the result
2113 *
2114 * Sets the secid to contain a u32 version of the smack label.
2115 */
2116static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
2117{
2118 struct smack_known *skp;
2119
2120 rcu_read_lock();
2121 skp = smk_of_task(smack_cred(cred));
2122 *secid = skp->smk_secid;
2123 rcu_read_unlock();
2124}
2125
2126/**
2127 * smack_kernel_act_as - Set the subjective context in a set of credentials
2128 * @new: points to the set of credentials to be modified.
2129 * @secid: specifies the security ID to be set
2130 *
2131 * Set the security data for a kernel service.
2132 */
2133static int smack_kernel_act_as(struct cred *new, u32 secid)
2134{
2135 struct task_smack *new_tsp = smack_cred(new);
2136
2137 new_tsp->smk_task = smack_from_secid(secid);
2138 return 0;
2139}
2140
2141/**
2142 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2143 * @new: points to the set of credentials to be modified
2144 * @inode: points to the inode to use as a reference
2145 *
2146 * Set the file creation context in a set of credentials to the same
2147 * as the objective context of the specified inode
2148 */
2149static int smack_kernel_create_files_as(struct cred *new,
2150 struct inode *inode)
2151{
2152 struct inode_smack *isp = smack_inode(inode);
2153 struct task_smack *tsp = smack_cred(new);
2154
2155 tsp->smk_forked = isp->smk_inode;
2156 tsp->smk_task = tsp->smk_forked;
2157 return 0;
2158}
2159
2160/**
2161 * smk_curacc_on_task - helper to log task related access
2162 * @p: the task object
2163 * @access: the access requested
2164 * @caller: name of the calling function for audit
2165 *
2166 * Return 0 if access is permitted
2167 */
2168static int smk_curacc_on_task(struct task_struct *p, int access,
2169 const char *caller)
2170{
2171 struct smk_audit_info ad;
2172 struct smack_known *skp = smk_of_task_struct_obj(p);
2173 int rc;
2174
2175 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2176 smk_ad_setfield_u_tsk(&ad, p);
2177 rc = smk_curacc(skp, access, &ad);
2178 rc = smk_bu_task(p, access, rc);
2179 return rc;
2180}
2181
2182/**
2183 * smack_task_setpgid - Smack check on setting pgid
2184 * @p: the task object
2185 * @pgid: unused
2186 *
2187 * Return 0 if write access is permitted
2188 */
2189static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2190{
2191 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2192}
2193
2194/**
2195 * smack_task_getpgid - Smack access check for getpgid
2196 * @p: the object task
2197 *
2198 * Returns 0 if current can read the object task, error code otherwise
2199 */
2200static int smack_task_getpgid(struct task_struct *p)
2201{
2202 return smk_curacc_on_task(p, MAY_READ, __func__);
2203}
2204
2205/**
2206 * smack_task_getsid - Smack access check for getsid
2207 * @p: the object task
2208 *
2209 * Returns 0 if current can read the object task, error code otherwise
2210 */
2211static int smack_task_getsid(struct task_struct *p)
2212{
2213 return smk_curacc_on_task(p, MAY_READ, __func__);
2214}
2215
2216/**
2217 * smack_current_getsecid_subj - get the subjective secid of the current task
2218 * @secid: where to put the result
2219 *
2220 * Sets the secid to contain a u32 version of the task's subjective smack label.
2221 */
2222static void smack_current_getsecid_subj(u32 *secid)
2223{
2224 struct smack_known *skp = smk_of_current();
2225
2226 *secid = skp->smk_secid;
2227}
2228
2229/**
2230 * smack_task_getsecid_obj - get the objective secid of the task
2231 * @p: the task
2232 * @secid: where to put the result
2233 *
2234 * Sets the secid to contain a u32 version of the task's objective smack label.
2235 */
2236static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid)
2237{
2238 struct smack_known *skp = smk_of_task_struct_obj(p);
2239
2240 *secid = skp->smk_secid;
2241}
2242
2243/**
2244 * smack_task_setnice - Smack check on setting nice
2245 * @p: the task object
2246 * @nice: unused
2247 *
2248 * Return 0 if write access is permitted
2249 */
2250static int smack_task_setnice(struct task_struct *p, int nice)
2251{
2252 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2253}
2254
2255/**
2256 * smack_task_setioprio - Smack check on setting ioprio
2257 * @p: the task object
2258 * @ioprio: unused
2259 *
2260 * Return 0 if write access is permitted
2261 */
2262static int smack_task_setioprio(struct task_struct *p, int ioprio)
2263{
2264 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2265}
2266
2267/**
2268 * smack_task_getioprio - Smack check on reading ioprio
2269 * @p: the task object
2270 *
2271 * Return 0 if read access is permitted
2272 */
2273static int smack_task_getioprio(struct task_struct *p)
2274{
2275 return smk_curacc_on_task(p, MAY_READ, __func__);
2276}
2277
2278/**
2279 * smack_task_setscheduler - Smack check on setting scheduler
2280 * @p: the task object
2281 *
2282 * Return 0 if read access is permitted
2283 */
2284static int smack_task_setscheduler(struct task_struct *p)
2285{
2286 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2287}
2288
2289/**
2290 * smack_task_getscheduler - Smack check on reading scheduler
2291 * @p: the task object
2292 *
2293 * Return 0 if read access is permitted
2294 */
2295static int smack_task_getscheduler(struct task_struct *p)
2296{
2297 return smk_curacc_on_task(p, MAY_READ, __func__);
2298}
2299
2300/**
2301 * smack_task_movememory - Smack check on moving memory
2302 * @p: the task object
2303 *
2304 * Return 0 if write access is permitted
2305 */
2306static int smack_task_movememory(struct task_struct *p)
2307{
2308 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2309}
2310
2311/**
2312 * smack_task_kill - Smack check on signal delivery
2313 * @p: the task object
2314 * @info: unused
2315 * @sig: unused
2316 * @cred: identifies the cred to use in lieu of current's
2317 *
2318 * Return 0 if write access is permitted
2319 *
2320 */
2321static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
2322 int sig, const struct cred *cred)
2323{
2324 struct smk_audit_info ad;
2325 struct smack_known *skp;
2326 struct smack_known *tkp = smk_of_task_struct_obj(p);
2327 int rc;
2328
2329 if (!sig)
2330 return 0; /* null signal; existence test */
2331
2332 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2333 smk_ad_setfield_u_tsk(&ad, p);
2334 /*
2335 * Sending a signal requires that the sender
2336 * can write the receiver.
2337 */
2338 if (cred == NULL) {
2339 rc = smk_curacc(tkp, MAY_DELIVER, &ad);
2340 rc = smk_bu_task(p, MAY_DELIVER, rc);
2341 return rc;
2342 }
2343 /*
2344 * If the cred isn't NULL we're dealing with some USB IO
2345 * specific behavior. This is not clean. For one thing
2346 * we can't take privilege into account.
2347 */
2348 skp = smk_of_task(smack_cred(cred));
2349 rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
2350 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
2351 return rc;
2352}
2353
2354/**
2355 * smack_task_to_inode - copy task smack into the inode blob
2356 * @p: task to copy from
2357 * @inode: inode to copy to
2358 *
2359 * Sets the smack pointer in the inode security blob
2360 */
2361static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2362{
2363 struct inode_smack *isp = smack_inode(inode);
2364 struct smack_known *skp = smk_of_task_struct_obj(p);
2365
2366 isp->smk_inode = skp;
2367 isp->smk_flags |= SMK_INODE_INSTANT;
2368}
2369
2370/*
2371 * Socket hooks.
2372 */
2373
2374/**
2375 * smack_sk_alloc_security - Allocate a socket blob
2376 * @sk: the socket
2377 * @family: unused
2378 * @gfp_flags: memory allocation flags
2379 *
2380 * Assign Smack pointers to current
2381 *
2382 * Returns 0 on success, -ENOMEM is there's no memory
2383 */
2384static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2385{
2386 struct smack_known *skp = smk_of_current();
2387 struct socket_smack *ssp;
2388
2389 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
2390 if (ssp == NULL)
2391 return -ENOMEM;
2392
2393 /*
2394 * Sockets created by kernel threads receive web label.
2395 */
2396 if (unlikely(current->flags & PF_KTHREAD)) {
2397 ssp->smk_in = &smack_known_web;
2398 ssp->smk_out = &smack_known_web;
2399 } else {
2400 ssp->smk_in = skp;
2401 ssp->smk_out = skp;
2402 }
2403 ssp->smk_packet = NULL;
2404
2405 sk->sk_security = ssp;
2406
2407 return 0;
2408}
2409
2410/**
2411 * smack_sk_free_security - Free a socket blob
2412 * @sk: the socket
2413 *
2414 * Clears the blob pointer
2415 */
2416static void smack_sk_free_security(struct sock *sk)
2417{
2418#ifdef SMACK_IPV6_PORT_LABELING
2419 struct smk_port_label *spp;
2420
2421 if (sk->sk_family == PF_INET6) {
2422 rcu_read_lock();
2423 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2424 if (spp->smk_sock != sk)
2425 continue;
2426 spp->smk_can_reuse = 1;
2427 break;
2428 }
2429 rcu_read_unlock();
2430 }
2431#endif
2432 kfree(sk->sk_security);
2433}
2434
2435/**
2436 * smack_sk_clone_security - Copy security context
2437 * @sk: the old socket
2438 * @newsk: the new socket
2439 *
2440 * Copy the security context of the old socket pointer to the cloned
2441 */
2442static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk)
2443{
2444 struct socket_smack *ssp_old = sk->sk_security;
2445 struct socket_smack *ssp_new = newsk->sk_security;
2446
2447 *ssp_new = *ssp_old;
2448}
2449
2450/**
2451* smack_ipv4host_label - check host based restrictions
2452* @sip: the object end
2453*
2454* looks for host based access restrictions
2455*
2456* This version will only be appropriate for really small sets of single label
2457* hosts. The caller is responsible for ensuring that the RCU read lock is
2458* taken before calling this function.
2459*
2460* Returns the label of the far end or NULL if it's not special.
2461*/
2462static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2463{
2464 struct smk_net4addr *snp;
2465 struct in_addr *siap = &sip->sin_addr;
2466
2467 if (siap->s_addr == 0)
2468 return NULL;
2469
2470 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2471 /*
2472 * we break after finding the first match because
2473 * the list is sorted from longest to shortest mask
2474 * so we have found the most specific match
2475 */
2476 if (snp->smk_host.s_addr ==
2477 (siap->s_addr & snp->smk_mask.s_addr))
2478 return snp->smk_label;
2479
2480 return NULL;
2481}
2482
2483/*
2484 * smk_ipv6_localhost - Check for local ipv6 host address
2485 * @sip: the address
2486 *
2487 * Returns boolean true if this is the localhost address
2488 */
2489static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2490{
2491 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2492 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2493
2494 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2495 ntohs(be16p[7]) == 1)
2496 return true;
2497 return false;
2498}
2499
2500/**
2501* smack_ipv6host_label - check host based restrictions
2502* @sip: the object end
2503*
2504* looks for host based access restrictions
2505*
2506* This version will only be appropriate for really small sets of single label
2507* hosts. The caller is responsible for ensuring that the RCU read lock is
2508* taken before calling this function.
2509*
2510* Returns the label of the far end or NULL if it's not special.
2511*/
2512static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2513{
2514 struct smk_net6addr *snp;
2515 struct in6_addr *sap = &sip->sin6_addr;
2516 int i;
2517 int found = 0;
2518
2519 /*
2520 * It's local. Don't look for a host label.
2521 */
2522 if (smk_ipv6_localhost(sip))
2523 return NULL;
2524
2525 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2526 /*
2527 * If the label is NULL the entry has
2528 * been renounced. Ignore it.
2529 */
2530 if (snp->smk_label == NULL)
2531 continue;
2532 /*
2533 * we break after finding the first match because
2534 * the list is sorted from longest to shortest mask
2535 * so we have found the most specific match
2536 */
2537 for (found = 1, i = 0; i < 8; i++) {
2538 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2539 snp->smk_host.s6_addr16[i]) {
2540 found = 0;
2541 break;
2542 }
2543 }
2544 if (found)
2545 return snp->smk_label;
2546 }
2547
2548 return NULL;
2549}
2550
2551/**
2552 * smack_netlbl_add - Set the secattr on a socket
2553 * @sk: the socket
2554 *
2555 * Attach the outbound smack value (smk_out) to the socket.
2556 *
2557 * Returns 0 on success or an error code
2558 */
2559static int smack_netlbl_add(struct sock *sk)
2560{
2561 struct socket_smack *ssp = sk->sk_security;
2562 struct smack_known *skp = ssp->smk_out;
2563 int rc;
2564
2565 local_bh_disable();
2566 bh_lock_sock_nested(sk);
2567
2568 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2569 switch (rc) {
2570 case 0:
2571 ssp->smk_state = SMK_NETLBL_LABELED;
2572 break;
2573 case -EDESTADDRREQ:
2574 ssp->smk_state = SMK_NETLBL_REQSKB;
2575 rc = 0;
2576 break;
2577 }
2578
2579 bh_unlock_sock(sk);
2580 local_bh_enable();
2581
2582 return rc;
2583}
2584
2585/**
2586 * smack_netlbl_delete - Remove the secattr from a socket
2587 * @sk: the socket
2588 *
2589 * Remove the outbound smack value from a socket
2590 */
2591static void smack_netlbl_delete(struct sock *sk)
2592{
2593 struct socket_smack *ssp = sk->sk_security;
2594
2595 /*
2596 * Take the label off the socket if one is set.
2597 */
2598 if (ssp->smk_state != SMK_NETLBL_LABELED)
2599 return;
2600
2601 local_bh_disable();
2602 bh_lock_sock_nested(sk);
2603 netlbl_sock_delattr(sk);
2604 bh_unlock_sock(sk);
2605 local_bh_enable();
2606 ssp->smk_state = SMK_NETLBL_UNLABELED;
2607}
2608
2609/**
2610 * smk_ipv4_check - Perform IPv4 host access checks
2611 * @sk: the socket
2612 * @sap: the destination address
2613 *
2614 * Set the correct secattr for the given socket based on the destination
2615 * address and perform any outbound access checks needed.
2616 *
2617 * Returns 0 on success or an error code.
2618 *
2619 */
2620static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
2621{
2622 struct smack_known *skp;
2623 int rc = 0;
2624 struct smack_known *hkp;
2625 struct socket_smack *ssp = sk->sk_security;
2626 struct smk_audit_info ad;
2627
2628 rcu_read_lock();
2629 hkp = smack_ipv4host_label(sap);
2630 if (hkp != NULL) {
2631#ifdef CONFIG_AUDIT
2632 struct lsm_network_audit net;
2633
2634 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2635 ad.a.u.net->family = sap->sin_family;
2636 ad.a.u.net->dport = sap->sin_port;
2637 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2638#endif
2639 skp = ssp->smk_out;
2640 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2641 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2642 /*
2643 * Clear the socket netlabel if it's set.
2644 */
2645 if (!rc)
2646 smack_netlbl_delete(sk);
2647 }
2648 rcu_read_unlock();
2649
2650 return rc;
2651}
2652
2653/**
2654 * smk_ipv6_check - check Smack access
2655 * @subject: subject Smack label
2656 * @object: object Smack label
2657 * @address: address
2658 * @act: the action being taken
2659 *
2660 * Check an IPv6 access
2661 */
2662static int smk_ipv6_check(struct smack_known *subject,
2663 struct smack_known *object,
2664 struct sockaddr_in6 *address, int act)
2665{
2666#ifdef CONFIG_AUDIT
2667 struct lsm_network_audit net;
2668#endif
2669 struct smk_audit_info ad;
2670 int rc;
2671
2672#ifdef CONFIG_AUDIT
2673 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2674 ad.a.u.net->family = PF_INET6;
2675 ad.a.u.net->dport = address->sin6_port;
2676 if (act == SMK_RECEIVING)
2677 ad.a.u.net->v6info.saddr = address->sin6_addr;
2678 else
2679 ad.a.u.net->v6info.daddr = address->sin6_addr;
2680#endif
2681 rc = smk_access(subject, object, MAY_WRITE, &ad);
2682 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2683 return rc;
2684}
2685
2686#ifdef SMACK_IPV6_PORT_LABELING
2687/**
2688 * smk_ipv6_port_label - Smack port access table management
2689 * @sock: socket
2690 * @address: address
2691 *
2692 * Create or update the port list entry
2693 */
2694static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2695{
2696 struct sock *sk = sock->sk;
2697 struct sockaddr_in6 *addr6;
2698 struct socket_smack *ssp = sock->sk->sk_security;
2699 struct smk_port_label *spp;
2700 unsigned short port = 0;
2701
2702 if (address == NULL) {
2703 /*
2704 * This operation is changing the Smack information
2705 * on the bound socket. Take the changes to the port
2706 * as well.
2707 */
2708 rcu_read_lock();
2709 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2710 if (sk != spp->smk_sock)
2711 continue;
2712 spp->smk_in = ssp->smk_in;
2713 spp->smk_out = ssp->smk_out;
2714 rcu_read_unlock();
2715 return;
2716 }
2717 /*
2718 * A NULL address is only used for updating existing
2719 * bound entries. If there isn't one, it's OK.
2720 */
2721 rcu_read_unlock();
2722 return;
2723 }
2724
2725 addr6 = (struct sockaddr_in6 *)address;
2726 port = ntohs(addr6->sin6_port);
2727 /*
2728 * This is a special case that is safely ignored.
2729 */
2730 if (port == 0)
2731 return;
2732
2733 /*
2734 * Look for an existing port list entry.
2735 * This is an indication that a port is getting reused.
2736 */
2737 rcu_read_lock();
2738 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2739 if (spp->smk_port != port || spp->smk_sock_type != sock->type)
2740 continue;
2741 if (spp->smk_can_reuse != 1) {
2742 rcu_read_unlock();
2743 return;
2744 }
2745 spp->smk_port = port;
2746 spp->smk_sock = sk;
2747 spp->smk_in = ssp->smk_in;
2748 spp->smk_out = ssp->smk_out;
2749 spp->smk_can_reuse = 0;
2750 rcu_read_unlock();
2751 return;
2752 }
2753 rcu_read_unlock();
2754 /*
2755 * A new port entry is required.
2756 */
2757 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2758 if (spp == NULL)
2759 return;
2760
2761 spp->smk_port = port;
2762 spp->smk_sock = sk;
2763 spp->smk_in = ssp->smk_in;
2764 spp->smk_out = ssp->smk_out;
2765 spp->smk_sock_type = sock->type;
2766 spp->smk_can_reuse = 0;
2767
2768 mutex_lock(&smack_ipv6_lock);
2769 list_add_rcu(&spp->list, &smk_ipv6_port_list);
2770 mutex_unlock(&smack_ipv6_lock);
2771 return;
2772}
2773
2774/**
2775 * smk_ipv6_port_check - check Smack port access
2776 * @sk: socket
2777 * @address: address
2778 * @act: the action being taken
2779 *
2780 * Create or update the port list entry
2781 */
2782static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2783 int act)
2784{
2785 struct smk_port_label *spp;
2786 struct socket_smack *ssp = sk->sk_security;
2787 struct smack_known *skp = NULL;
2788 unsigned short port;
2789 struct smack_known *object;
2790
2791 if (act == SMK_RECEIVING) {
2792 skp = smack_ipv6host_label(address);
2793 object = ssp->smk_in;
2794 } else {
2795 skp = ssp->smk_out;
2796 object = smack_ipv6host_label(address);
2797 }
2798
2799 /*
2800 * The other end is a single label host.
2801 */
2802 if (skp != NULL && object != NULL)
2803 return smk_ipv6_check(skp, object, address, act);
2804 if (skp == NULL)
2805 skp = smack_net_ambient;
2806 if (object == NULL)
2807 object = smack_net_ambient;
2808
2809 /*
2810 * It's remote, so port lookup does no good.
2811 */
2812 if (!smk_ipv6_localhost(address))
2813 return smk_ipv6_check(skp, object, address, act);
2814
2815 /*
2816 * It's local so the send check has to have passed.
2817 */
2818 if (act == SMK_RECEIVING)
2819 return 0;
2820
2821 port = ntohs(address->sin6_port);
2822 rcu_read_lock();
2823 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2824 if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
2825 continue;
2826 object = spp->smk_in;
2827 if (act == SMK_CONNECTING)
2828 ssp->smk_packet = spp->smk_out;
2829 break;
2830 }
2831 rcu_read_unlock();
2832
2833 return smk_ipv6_check(skp, object, address, act);
2834}
2835#endif
2836
2837/**
2838 * smack_inode_setsecurity - set smack xattrs
2839 * @inode: the object
2840 * @name: attribute name
2841 * @value: attribute value
2842 * @size: size of the attribute
2843 * @flags: unused
2844 *
2845 * Sets the named attribute in the appropriate blob
2846 *
2847 * Returns 0 on success, or an error code
2848 */
2849static int smack_inode_setsecurity(struct inode *inode, const char *name,
2850 const void *value, size_t size, int flags)
2851{
2852 struct smack_known *skp;
2853 struct inode_smack *nsp = smack_inode(inode);
2854 struct socket_smack *ssp;
2855 struct socket *sock;
2856 int rc = 0;
2857
2858 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2859 return -EINVAL;
2860
2861 if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
2862 if (!S_ISDIR(inode->i_mode) || size != TRANS_TRUE_SIZE ||
2863 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
2864 return -EINVAL;
2865
2866 nsp->smk_flags |= SMK_INODE_TRANSMUTE;
2867 return 0;
2868 }
2869
2870 skp = smk_import_entry(value, size);
2871 if (IS_ERR(skp))
2872 return PTR_ERR(skp);
2873
2874 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2875 nsp->smk_inode = skp;
2876 nsp->smk_flags |= SMK_INODE_INSTANT;
2877 return 0;
2878 }
2879 /*
2880 * The rest of the Smack xattrs are only on sockets.
2881 */
2882 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2883 return -EOPNOTSUPP;
2884
2885 sock = SOCKET_I(inode);
2886 if (sock == NULL || sock->sk == NULL)
2887 return -EOPNOTSUPP;
2888
2889 ssp = sock->sk->sk_security;
2890
2891 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2892 ssp->smk_in = skp;
2893 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2894 ssp->smk_out = skp;
2895 if (sock->sk->sk_family == PF_INET) {
2896 rc = smack_netlbl_add(sock->sk);
2897 if (rc != 0)
2898 printk(KERN_WARNING
2899 "Smack: \"%s\" netlbl error %d.\n",
2900 __func__, -rc);
2901 }
2902 } else
2903 return -EOPNOTSUPP;
2904
2905#ifdef SMACK_IPV6_PORT_LABELING
2906 if (sock->sk->sk_family == PF_INET6)
2907 smk_ipv6_port_label(sock, NULL);
2908#endif
2909
2910 return 0;
2911}
2912
2913/**
2914 * smack_socket_post_create - finish socket setup
2915 * @sock: the socket
2916 * @family: protocol family
2917 * @type: unused
2918 * @protocol: unused
2919 * @kern: unused
2920 *
2921 * Sets the netlabel information on the socket
2922 *
2923 * Returns 0 on success, and error code otherwise
2924 */
2925static int smack_socket_post_create(struct socket *sock, int family,
2926 int type, int protocol, int kern)
2927{
2928 struct socket_smack *ssp;
2929
2930 if (sock->sk == NULL)
2931 return 0;
2932
2933 /*
2934 * Sockets created by kernel threads receive web label.
2935 */
2936 if (unlikely(current->flags & PF_KTHREAD)) {
2937 ssp = sock->sk->sk_security;
2938 ssp->smk_in = &smack_known_web;
2939 ssp->smk_out = &smack_known_web;
2940 }
2941
2942 if (family != PF_INET)
2943 return 0;
2944 /*
2945 * Set the outbound netlbl.
2946 */
2947 return smack_netlbl_add(sock->sk);
2948}
2949
2950/**
2951 * smack_socket_socketpair - create socket pair
2952 * @socka: one socket
2953 * @sockb: another socket
2954 *
2955 * Cross reference the peer labels for SO_PEERSEC
2956 *
2957 * Returns 0
2958 */
2959static int smack_socket_socketpair(struct socket *socka,
2960 struct socket *sockb)
2961{
2962 struct socket_smack *asp = socka->sk->sk_security;
2963 struct socket_smack *bsp = sockb->sk->sk_security;
2964
2965 asp->smk_packet = bsp->smk_out;
2966 bsp->smk_packet = asp->smk_out;
2967
2968 return 0;
2969}
2970
2971#ifdef SMACK_IPV6_PORT_LABELING
2972/**
2973 * smack_socket_bind - record port binding information.
2974 * @sock: the socket
2975 * @address: the port address
2976 * @addrlen: size of the address
2977 *
2978 * Records the label bound to a port.
2979 *
2980 * Returns 0 on success, and error code otherwise
2981 */
2982static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
2983 int addrlen)
2984{
2985 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
2986 if (addrlen < SIN6_LEN_RFC2133 ||
2987 address->sa_family != AF_INET6)
2988 return -EINVAL;
2989 smk_ipv6_port_label(sock, address);
2990 }
2991 return 0;
2992}
2993#endif /* SMACK_IPV6_PORT_LABELING */
2994
2995/**
2996 * smack_socket_connect - connect access check
2997 * @sock: the socket
2998 * @sap: the other end
2999 * @addrlen: size of sap
3000 *
3001 * Verifies that a connection may be possible
3002 *
3003 * Returns 0 on success, and error code otherwise
3004 */
3005static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
3006 int addrlen)
3007{
3008 int rc = 0;
3009
3010 if (sock->sk == NULL)
3011 return 0;
3012 if (sock->sk->sk_family != PF_INET &&
3013 (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6))
3014 return 0;
3015 if (addrlen < offsetofend(struct sockaddr, sa_family))
3016 return 0;
3017 if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
3018 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
3019 struct smack_known *rsp = NULL;
3020
3021 if (addrlen < SIN6_LEN_RFC2133)
3022 return 0;
3023 if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
3024 rsp = smack_ipv6host_label(sip);
3025 if (rsp != NULL) {
3026 struct socket_smack *ssp = sock->sk->sk_security;
3027
3028 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
3029 SMK_CONNECTING);
3030 }
3031#ifdef SMACK_IPV6_PORT_LABELING
3032 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
3033#endif
3034
3035 return rc;
3036 }
3037 if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
3038 return 0;
3039 rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
3040 return rc;
3041}
3042
3043/**
3044 * smack_flags_to_may - convert S_ to MAY_ values
3045 * @flags: the S_ value
3046 *
3047 * Returns the equivalent MAY_ value
3048 */
3049static int smack_flags_to_may(int flags)
3050{
3051 int may = 0;
3052
3053 if (flags & S_IRUGO)
3054 may |= MAY_READ;
3055 if (flags & S_IWUGO)
3056 may |= MAY_WRITE;
3057 if (flags & S_IXUGO)
3058 may |= MAY_EXEC;
3059
3060 return may;
3061}
3062
3063/**
3064 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
3065 * @msg: the object
3066 *
3067 * Returns 0
3068 */
3069static int smack_msg_msg_alloc_security(struct msg_msg *msg)
3070{
3071 struct smack_known **blob = smack_msg_msg(msg);
3072
3073 *blob = smk_of_current();
3074 return 0;
3075}
3076
3077/**
3078 * smack_of_ipc - the smack pointer for the ipc
3079 * @isp: the object
3080 *
3081 * Returns a pointer to the smack value
3082 */
3083static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
3084{
3085 struct smack_known **blob = smack_ipc(isp);
3086
3087 return *blob;
3088}
3089
3090/**
3091 * smack_ipc_alloc_security - Set the security blob for ipc
3092 * @isp: the object
3093 *
3094 * Returns 0
3095 */
3096static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
3097{
3098 struct smack_known **blob = smack_ipc(isp);
3099
3100 *blob = smk_of_current();
3101 return 0;
3102}
3103
3104/**
3105 * smk_curacc_shm : check if current has access on shm
3106 * @isp : the object
3107 * @access : access requested
3108 *
3109 * Returns 0 if current has the requested access, error code otherwise
3110 */
3111static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
3112{
3113 struct smack_known *ssp = smack_of_ipc(isp);
3114 struct smk_audit_info ad;
3115 int rc;
3116
3117#ifdef CONFIG_AUDIT
3118 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3119 ad.a.u.ipc_id = isp->id;
3120#endif
3121 rc = smk_curacc(ssp, access, &ad);
3122 rc = smk_bu_current("shm", ssp, access, rc);
3123 return rc;
3124}
3125
3126/**
3127 * smack_shm_associate - Smack access check for shm
3128 * @isp: the object
3129 * @shmflg: access requested
3130 *
3131 * Returns 0 if current has the requested access, error code otherwise
3132 */
3133static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
3134{
3135 int may;
3136
3137 may = smack_flags_to_may(shmflg);
3138 return smk_curacc_shm(isp, may);
3139}
3140
3141/**
3142 * smack_shm_shmctl - Smack access check for shm
3143 * @isp: the object
3144 * @cmd: what it wants to do
3145 *
3146 * Returns 0 if current has the requested access, error code otherwise
3147 */
3148static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd)
3149{
3150 int may;
3151
3152 switch (cmd) {
3153 case IPC_STAT:
3154 case SHM_STAT:
3155 case SHM_STAT_ANY:
3156 may = MAY_READ;
3157 break;
3158 case IPC_SET:
3159 case SHM_LOCK:
3160 case SHM_UNLOCK:
3161 case IPC_RMID:
3162 may = MAY_READWRITE;
3163 break;
3164 case IPC_INFO:
3165 case SHM_INFO:
3166 /*
3167 * System level information.
3168 */
3169 return 0;
3170 default:
3171 return -EINVAL;
3172 }
3173 return smk_curacc_shm(isp, may);
3174}
3175
3176/**
3177 * smack_shm_shmat - Smack access for shmat
3178 * @isp: the object
3179 * @shmaddr: unused
3180 * @shmflg: access requested
3181 *
3182 * Returns 0 if current has the requested access, error code otherwise
3183 */
3184static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr,
3185 int shmflg)
3186{
3187 int may;
3188
3189 may = smack_flags_to_may(shmflg);
3190 return smk_curacc_shm(isp, may);
3191}
3192
3193/**
3194 * smk_curacc_sem : check if current has access on sem
3195 * @isp : the object
3196 * @access : access requested
3197 *
3198 * Returns 0 if current has the requested access, error code otherwise
3199 */
3200static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
3201{
3202 struct smack_known *ssp = smack_of_ipc(isp);
3203 struct smk_audit_info ad;
3204 int rc;
3205
3206#ifdef CONFIG_AUDIT
3207 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3208 ad.a.u.ipc_id = isp->id;
3209#endif
3210 rc = smk_curacc(ssp, access, &ad);
3211 rc = smk_bu_current("sem", ssp, access, rc);
3212 return rc;
3213}
3214
3215/**
3216 * smack_sem_associate - Smack access check for sem
3217 * @isp: the object
3218 * @semflg: access requested
3219 *
3220 * Returns 0 if current has the requested access, error code otherwise
3221 */
3222static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
3223{
3224 int may;
3225
3226 may = smack_flags_to_may(semflg);
3227 return smk_curacc_sem(isp, may);
3228}
3229
3230/**
3231 * smack_sem_semctl - Smack access check for sem
3232 * @isp: the object
3233 * @cmd: what it wants to do
3234 *
3235 * Returns 0 if current has the requested access, error code otherwise
3236 */
3237static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd)
3238{
3239 int may;
3240
3241 switch (cmd) {
3242 case GETPID:
3243 case GETNCNT:
3244 case GETZCNT:
3245 case GETVAL:
3246 case GETALL:
3247 case IPC_STAT:
3248 case SEM_STAT:
3249 case SEM_STAT_ANY:
3250 may = MAY_READ;
3251 break;
3252 case SETVAL:
3253 case SETALL:
3254 case IPC_RMID:
3255 case IPC_SET:
3256 may = MAY_READWRITE;
3257 break;
3258 case IPC_INFO:
3259 case SEM_INFO:
3260 /*
3261 * System level information
3262 */
3263 return 0;
3264 default:
3265 return -EINVAL;
3266 }
3267
3268 return smk_curacc_sem(isp, may);
3269}
3270
3271/**
3272 * smack_sem_semop - Smack checks of semaphore operations
3273 * @isp: the object
3274 * @sops: unused
3275 * @nsops: unused
3276 * @alter: unused
3277 *
3278 * Treated as read and write in all cases.
3279 *
3280 * Returns 0 if access is allowed, error code otherwise
3281 */
3282static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops,
3283 unsigned nsops, int alter)
3284{
3285 return smk_curacc_sem(isp, MAY_READWRITE);
3286}
3287
3288/**
3289 * smk_curacc_msq : helper to check if current has access on msq
3290 * @isp : the msq
3291 * @access : access requested
3292 *
3293 * return 0 if current has access, error otherwise
3294 */
3295static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
3296{
3297 struct smack_known *msp = smack_of_ipc(isp);
3298 struct smk_audit_info ad;
3299 int rc;
3300
3301#ifdef CONFIG_AUDIT
3302 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3303 ad.a.u.ipc_id = isp->id;
3304#endif
3305 rc = smk_curacc(msp, access, &ad);
3306 rc = smk_bu_current("msq", msp, access, rc);
3307 return rc;
3308}
3309
3310/**
3311 * smack_msg_queue_associate - Smack access check for msg_queue
3312 * @isp: the object
3313 * @msqflg: access requested
3314 *
3315 * Returns 0 if current has the requested access, error code otherwise
3316 */
3317static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
3318{
3319 int may;
3320
3321 may = smack_flags_to_may(msqflg);
3322 return smk_curacc_msq(isp, may);
3323}
3324
3325/**
3326 * smack_msg_queue_msgctl - Smack access check for msg_queue
3327 * @isp: the object
3328 * @cmd: what it wants to do
3329 *
3330 * Returns 0 if current has the requested access, error code otherwise
3331 */
3332static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd)
3333{
3334 int may;
3335
3336 switch (cmd) {
3337 case IPC_STAT:
3338 case MSG_STAT:
3339 case MSG_STAT_ANY:
3340 may = MAY_READ;
3341 break;
3342 case IPC_SET:
3343 case IPC_RMID:
3344 may = MAY_READWRITE;
3345 break;
3346 case IPC_INFO:
3347 case MSG_INFO:
3348 /*
3349 * System level information
3350 */
3351 return 0;
3352 default:
3353 return -EINVAL;
3354 }
3355
3356 return smk_curacc_msq(isp, may);
3357}
3358
3359/**
3360 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3361 * @isp: the object
3362 * @msg: unused
3363 * @msqflg: access requested
3364 *
3365 * Returns 0 if current has the requested access, error code otherwise
3366 */
3367static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg,
3368 int msqflg)
3369{
3370 int may;
3371
3372 may = smack_flags_to_may(msqflg);
3373 return smk_curacc_msq(isp, may);
3374}
3375
3376/**
3377 * smack_msg_queue_msgrcv - Smack access check for msg_queue
3378 * @isp: the object
3379 * @msg: unused
3380 * @target: unused
3381 * @type: unused
3382 * @mode: unused
3383 *
3384 * Returns 0 if current has read and write access, error code otherwise
3385 */
3386static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp,
3387 struct msg_msg *msg,
3388 struct task_struct *target, long type,
3389 int mode)
3390{
3391 return smk_curacc_msq(isp, MAY_READWRITE);
3392}
3393
3394/**
3395 * smack_ipc_permission - Smack access for ipc_permission()
3396 * @ipp: the object permissions
3397 * @flag: access requested
3398 *
3399 * Returns 0 if current has read and write access, error code otherwise
3400 */
3401static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3402{
3403 struct smack_known **blob = smack_ipc(ipp);
3404 struct smack_known *iskp = *blob;
3405 int may = smack_flags_to_may(flag);
3406 struct smk_audit_info ad;
3407 int rc;
3408
3409#ifdef CONFIG_AUDIT
3410 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3411 ad.a.u.ipc_id = ipp->id;
3412#endif
3413 rc = smk_curacc(iskp, may, &ad);
3414 rc = smk_bu_current("svipc", iskp, may, rc);
3415 return rc;
3416}
3417
3418/**
3419 * smack_ipc_getsecid - Extract smack security id
3420 * @ipp: the object permissions
3421 * @secid: where result will be saved
3422 */
3423static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
3424{
3425 struct smack_known **blob = smack_ipc(ipp);
3426 struct smack_known *iskp = *blob;
3427
3428 *secid = iskp->smk_secid;
3429}
3430
3431/**
3432 * smack_d_instantiate - Make sure the blob is correct on an inode
3433 * @opt_dentry: dentry where inode will be attached
3434 * @inode: the object
3435 *
3436 * Set the inode's security blob if it hasn't been done already.
3437 */
3438static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3439{
3440 struct super_block *sbp;
3441 struct superblock_smack *sbsp;
3442 struct inode_smack *isp;
3443 struct smack_known *skp;
3444 struct smack_known *ckp = smk_of_current();
3445 struct smack_known *final;
3446 char trattr[TRANS_TRUE_SIZE];
3447 int transflag = 0;
3448 int rc;
3449 struct dentry *dp;
3450
3451 if (inode == NULL)
3452 return;
3453
3454 isp = smack_inode(inode);
3455
3456 /*
3457 * If the inode is already instantiated
3458 * take the quick way out
3459 */
3460 if (isp->smk_flags & SMK_INODE_INSTANT)
3461 return;
3462
3463 sbp = inode->i_sb;
3464 sbsp = smack_superblock(sbp);
3465 /*
3466 * We're going to use the superblock default label
3467 * if there's no label on the file.
3468 */
3469 final = sbsp->smk_default;
3470
3471 /*
3472 * If this is the root inode the superblock
3473 * may be in the process of initialization.
3474 * If that is the case use the root value out
3475 * of the superblock.
3476 */
3477 if (opt_dentry->d_parent == opt_dentry) {
3478 switch (sbp->s_magic) {
3479 case CGROUP_SUPER_MAGIC:
3480 case CGROUP2_SUPER_MAGIC:
3481 /*
3482 * The cgroup filesystem is never mounted,
3483 * so there's no opportunity to set the mount
3484 * options.
3485 */
3486 sbsp->smk_root = &smack_known_star;
3487 sbsp->smk_default = &smack_known_star;
3488 isp->smk_inode = sbsp->smk_root;
3489 break;
3490 case TMPFS_MAGIC:
3491 /*
3492 * What about shmem/tmpfs anonymous files with dentry
3493 * obtained from d_alloc_pseudo()?
3494 */
3495 isp->smk_inode = smk_of_current();
3496 break;
3497 case PIPEFS_MAGIC:
3498 isp->smk_inode = smk_of_current();
3499 break;
3500 case SOCKFS_MAGIC:
3501 /*
3502 * Socket access is controlled by the socket
3503 * structures associated with the task involved.
3504 */
3505 isp->smk_inode = &smack_known_star;
3506 break;
3507 default:
3508 isp->smk_inode = sbsp->smk_root;
3509 break;
3510 }
3511 isp->smk_flags |= SMK_INODE_INSTANT;
3512 return;
3513 }
3514
3515 /*
3516 * This is pretty hackish.
3517 * Casey says that we shouldn't have to do
3518 * file system specific code, but it does help
3519 * with keeping it simple.
3520 */
3521 switch (sbp->s_magic) {
3522 case SMACK_MAGIC:
3523 case CGROUP_SUPER_MAGIC:
3524 case CGROUP2_SUPER_MAGIC:
3525 /*
3526 * Casey says that it's a little embarrassing
3527 * that the smack file system doesn't do
3528 * extended attributes.
3529 *
3530 * Cgroupfs is special
3531 */
3532 final = &smack_known_star;
3533 break;
3534 case DEVPTS_SUPER_MAGIC:
3535 /*
3536 * devpts seems content with the label of the task.
3537 * Programs that change smack have to treat the
3538 * pty with respect.
3539 */
3540 final = ckp;
3541 break;
3542 case PROC_SUPER_MAGIC:
3543 /*
3544 * Casey says procfs appears not to care.
3545 * The superblock default suffices.
3546 */
3547 break;
3548 case TMPFS_MAGIC:
3549 /*
3550 * Device labels should come from the filesystem,
3551 * but watch out, because they're volitile,
3552 * getting recreated on every reboot.
3553 */
3554 final = &smack_known_star;
3555 /*
3556 * If a smack value has been set we want to use it,
3557 * but since tmpfs isn't giving us the opportunity
3558 * to set mount options simulate setting the
3559 * superblock default.
3560 */
3561 fallthrough;
3562 default:
3563 /*
3564 * This isn't an understood special case.
3565 * Get the value from the xattr.
3566 */
3567
3568 /*
3569 * UNIX domain sockets use lower level socket data.
3570 */
3571 if (S_ISSOCK(inode->i_mode)) {
3572 final = &smack_known_star;
3573 break;
3574 }
3575 /*
3576 * No xattr support means, alas, no SMACK label.
3577 * Use the aforeapplied default.
3578 * It would be curious if the label of the task
3579 * does not match that assigned.
3580 */
3581 if (!(inode->i_opflags & IOP_XATTR))
3582 break;
3583 /*
3584 * Get the dentry for xattr.
3585 */
3586 dp = dget(opt_dentry);
3587 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3588 if (!IS_ERR_OR_NULL(skp))
3589 final = skp;
3590
3591 /*
3592 * Transmuting directory
3593 */
3594 if (S_ISDIR(inode->i_mode)) {
3595 /*
3596 * If this is a new directory and the label was
3597 * transmuted when the inode was initialized
3598 * set the transmute attribute on the directory
3599 * and mark the inode.
3600 *
3601 * If there is a transmute attribute on the
3602 * directory mark the inode.
3603 */
3604 rc = __vfs_getxattr(dp, inode,
3605 XATTR_NAME_SMACKTRANSMUTE, trattr,
3606 TRANS_TRUE_SIZE);
3607 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3608 TRANS_TRUE_SIZE) != 0)
3609 rc = -EINVAL;
3610 if (rc >= 0)
3611 transflag = SMK_INODE_TRANSMUTE;
3612 }
3613 /*
3614 * Don't let the exec or mmap label be "*" or "@".
3615 */
3616 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3617 if (IS_ERR(skp) || skp == &smack_known_star ||
3618 skp == &smack_known_web)
3619 skp = NULL;
3620 isp->smk_task = skp;
3621
3622 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3623 if (IS_ERR(skp) || skp == &smack_known_star ||
3624 skp == &smack_known_web)
3625 skp = NULL;
3626 isp->smk_mmap = skp;
3627
3628 dput(dp);
3629 break;
3630 }
3631
3632 if (final == NULL)
3633 isp->smk_inode = ckp;
3634 else
3635 isp->smk_inode = final;
3636
3637 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3638
3639 return;
3640}
3641
3642/**
3643 * smack_getselfattr - Smack current process attribute
3644 * @attr: which attribute to fetch
3645 * @ctx: buffer to receive the result
3646 * @size: available size in, actual size out
3647 * @flags: unused
3648 *
3649 * Fill the passed user space @ctx with the details of the requested
3650 * attribute.
3651 *
3652 * Returns the number of attributes on success, an error code otherwise.
3653 * There will only ever be one attribute.
3654 */
3655static int smack_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
3656 u32 *size, u32 flags)
3657{
3658 int rc;
3659 struct smack_known *skp;
3660
3661 if (attr != LSM_ATTR_CURRENT)
3662 return -EOPNOTSUPP;
3663
3664 skp = smk_of_current();
3665 rc = lsm_fill_user_ctx(ctx, size,
3666 skp->smk_known, strlen(skp->smk_known) + 1,
3667 LSM_ID_SMACK, 0);
3668 return (!rc ? 1 : rc);
3669}
3670
3671/**
3672 * smack_getprocattr - Smack process attribute access
3673 * @p: the object task
3674 * @name: the name of the attribute in /proc/.../attr
3675 * @value: where to put the result
3676 *
3677 * Places a copy of the task Smack into value
3678 *
3679 * Returns the length of the smack label or an error code
3680 */
3681static int smack_getprocattr(struct task_struct *p, const char *name, char **value)
3682{
3683 struct smack_known *skp = smk_of_task_struct_obj(p);
3684 char *cp;
3685 int slen;
3686
3687 if (strcmp(name, "current") != 0)
3688 return -EINVAL;
3689
3690 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3691 if (cp == NULL)
3692 return -ENOMEM;
3693
3694 slen = strlen(cp);
3695 *value = cp;
3696 return slen;
3697}
3698
3699/**
3700 * do_setattr - Smack process attribute setting
3701 * @attr: the ID of the attribute
3702 * @value: the value to set
3703 * @size: the size of the value
3704 *
3705 * Sets the Smack value of the task. Only setting self
3706 * is permitted and only with privilege
3707 *
3708 * Returns the length of the smack label or an error code
3709 */
3710static int do_setattr(u64 attr, void *value, size_t size)
3711{
3712 struct task_smack *tsp = smack_cred(current_cred());
3713 struct cred *new;
3714 struct smack_known *skp;
3715 struct smack_known_list_elem *sklep;
3716 int rc;
3717
3718 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3719 return -EPERM;
3720
3721 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3722 return -EINVAL;
3723
3724 if (attr != LSM_ATTR_CURRENT)
3725 return -EOPNOTSUPP;
3726
3727 skp = smk_import_entry(value, size);
3728 if (IS_ERR(skp))
3729 return PTR_ERR(skp);
3730
3731 /*
3732 * No process is ever allowed the web ("@") label
3733 * and the star ("*") label.
3734 */
3735 if (skp == &smack_known_web || skp == &smack_known_star)
3736 return -EINVAL;
3737
3738 if (!smack_privileged(CAP_MAC_ADMIN)) {
3739 rc = -EPERM;
3740 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3741 if (sklep->smk_label == skp) {
3742 rc = 0;
3743 break;
3744 }
3745 if (rc)
3746 return rc;
3747 }
3748
3749 new = prepare_creds();
3750 if (new == NULL)
3751 return -ENOMEM;
3752
3753 tsp = smack_cred(new);
3754 tsp->smk_task = skp;
3755 /*
3756 * process can change its label only once
3757 */
3758 smk_destroy_label_list(&tsp->smk_relabel);
3759
3760 commit_creds(new);
3761 return size;
3762}
3763
3764/**
3765 * smack_setselfattr - Set a Smack process attribute
3766 * @attr: which attribute to set
3767 * @ctx: buffer containing the data
3768 * @size: size of @ctx
3769 * @flags: unused
3770 *
3771 * Fill the passed user space @ctx with the details of the requested
3772 * attribute.
3773 *
3774 * Returns 0 on success, an error code otherwise.
3775 */
3776static int smack_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
3777 u32 size, u32 flags)
3778{
3779 int rc;
3780
3781 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
3782 if (rc > 0)
3783 return 0;
3784 return rc;
3785}
3786
3787/**
3788 * smack_setprocattr - Smack process attribute setting
3789 * @name: the name of the attribute in /proc/.../attr
3790 * @value: the value to set
3791 * @size: the size of the value
3792 *
3793 * Sets the Smack value of the task. Only setting self
3794 * is permitted and only with privilege
3795 *
3796 * Returns the length of the smack label or an error code
3797 */
3798static int smack_setprocattr(const char *name, void *value, size_t size)
3799{
3800 int attr = lsm_name_to_attr(name);
3801
3802 if (attr != LSM_ATTR_UNDEF)
3803 return do_setattr(attr, value, size);
3804 return -EINVAL;
3805}
3806
3807/**
3808 * smack_unix_stream_connect - Smack access on UDS
3809 * @sock: one sock
3810 * @other: the other sock
3811 * @newsk: unused
3812 *
3813 * Return 0 if a subject with the smack of sock could access
3814 * an object with the smack of other, otherwise an error code
3815 */
3816static int smack_unix_stream_connect(struct sock *sock,
3817 struct sock *other, struct sock *newsk)
3818{
3819 struct smack_known *skp;
3820 struct smack_known *okp;
3821 struct socket_smack *ssp = sock->sk_security;
3822 struct socket_smack *osp = other->sk_security;
3823 struct socket_smack *nsp = newsk->sk_security;
3824 struct smk_audit_info ad;
3825 int rc = 0;
3826#ifdef CONFIG_AUDIT
3827 struct lsm_network_audit net;
3828#endif
3829
3830 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3831 skp = ssp->smk_out;
3832 okp = osp->smk_in;
3833#ifdef CONFIG_AUDIT
3834 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3835 smk_ad_setfield_u_net_sk(&ad, other);
3836#endif
3837 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3838 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3839 if (rc == 0) {
3840 okp = osp->smk_out;
3841 skp = ssp->smk_in;
3842 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3843 rc = smk_bu_note("UDS connect", okp, skp,
3844 MAY_WRITE, rc);
3845 }
3846 }
3847
3848 /*
3849 * Cross reference the peer labels for SO_PEERSEC.
3850 */
3851 if (rc == 0) {
3852 nsp->smk_packet = ssp->smk_out;
3853 ssp->smk_packet = osp->smk_out;
3854 }
3855
3856 return rc;
3857}
3858
3859/**
3860 * smack_unix_may_send - Smack access on UDS
3861 * @sock: one socket
3862 * @other: the other socket
3863 *
3864 * Return 0 if a subject with the smack of sock could access
3865 * an object with the smack of other, otherwise an error code
3866 */
3867static int smack_unix_may_send(struct socket *sock, struct socket *other)
3868{
3869 struct socket_smack *ssp = sock->sk->sk_security;
3870 struct socket_smack *osp = other->sk->sk_security;
3871 struct smk_audit_info ad;
3872 int rc;
3873
3874#ifdef CONFIG_AUDIT
3875 struct lsm_network_audit net;
3876
3877 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3878 smk_ad_setfield_u_net_sk(&ad, other->sk);
3879#endif
3880
3881 if (smack_privileged(CAP_MAC_OVERRIDE))
3882 return 0;
3883
3884 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3885 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3886 return rc;
3887}
3888
3889/**
3890 * smack_socket_sendmsg - Smack check based on destination host
3891 * @sock: the socket
3892 * @msg: the message
3893 * @size: the size of the message
3894 *
3895 * Return 0 if the current subject can write to the destination host.
3896 * For IPv4 this is only a question if the destination is a single label host.
3897 * For IPv6 this is a check against the label of the port.
3898 */
3899static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3900 int size)
3901{
3902 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3903#if IS_ENABLED(CONFIG_IPV6)
3904 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3905#endif
3906#ifdef SMACK_IPV6_SECMARK_LABELING
3907 struct socket_smack *ssp = sock->sk->sk_security;
3908 struct smack_known *rsp;
3909#endif
3910 int rc = 0;
3911
3912 /*
3913 * Perfectly reasonable for this to be NULL
3914 */
3915 if (sip == NULL)
3916 return 0;
3917
3918 switch (sock->sk->sk_family) {
3919 case AF_INET:
3920 if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
3921 sip->sin_family != AF_INET)
3922 return -EINVAL;
3923 rc = smk_ipv4_check(sock->sk, sip);
3924 break;
3925#if IS_ENABLED(CONFIG_IPV6)
3926 case AF_INET6:
3927 if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
3928 sap->sin6_family != AF_INET6)
3929 return -EINVAL;
3930#ifdef SMACK_IPV6_SECMARK_LABELING
3931 rsp = smack_ipv6host_label(sap);
3932 if (rsp != NULL)
3933 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3934 SMK_CONNECTING);
3935#endif
3936#ifdef SMACK_IPV6_PORT_LABELING
3937 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3938#endif
3939#endif /* IS_ENABLED(CONFIG_IPV6) */
3940 break;
3941 }
3942 return rc;
3943}
3944
3945/**
3946 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3947 * @sap: netlabel secattr
3948 * @ssp: socket security information
3949 *
3950 * Returns a pointer to a Smack label entry found on the label list.
3951 */
3952static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3953 struct socket_smack *ssp)
3954{
3955 struct smack_known *skp;
3956 int found = 0;
3957 int acat;
3958 int kcat;
3959
3960 /*
3961 * Netlabel found it in the cache.
3962 */
3963 if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
3964 return (struct smack_known *)sap->cache->data;
3965
3966 if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
3967 /*
3968 * Looks like a fallback, which gives us a secid.
3969 */
3970 return smack_from_secid(sap->attr.secid);
3971
3972 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3973 /*
3974 * Looks like a CIPSO packet.
3975 * If there are flags but no level netlabel isn't
3976 * behaving the way we expect it to.
3977 *
3978 * Look it up in the label table
3979 * Without guidance regarding the smack value
3980 * for the packet fall back on the network
3981 * ambient value.
3982 */
3983 rcu_read_lock();
3984 list_for_each_entry_rcu(skp, &smack_known_list, list) {
3985 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3986 continue;
3987 /*
3988 * Compare the catsets. Use the netlbl APIs.
3989 */
3990 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
3991 if ((skp->smk_netlabel.flags &
3992 NETLBL_SECATTR_MLS_CAT) == 0)
3993 found = 1;
3994 break;
3995 }
3996 for (acat = -1, kcat = -1; acat == kcat; ) {
3997 acat = netlbl_catmap_walk(sap->attr.mls.cat,
3998 acat + 1);
3999 kcat = netlbl_catmap_walk(
4000 skp->smk_netlabel.attr.mls.cat,
4001 kcat + 1);
4002 if (acat < 0 || kcat < 0)
4003 break;
4004 }
4005 if (acat == kcat) {
4006 found = 1;
4007 break;
4008 }
4009 }
4010 rcu_read_unlock();
4011
4012 if (found)
4013 return skp;
4014
4015 if (ssp != NULL && ssp->smk_in == &smack_known_star)
4016 return &smack_known_web;
4017 return &smack_known_star;
4018 }
4019 /*
4020 * Without guidance regarding the smack value
4021 * for the packet fall back on the network
4022 * ambient value.
4023 */
4024 return smack_net_ambient;
4025}
4026
4027#if IS_ENABLED(CONFIG_IPV6)
4028static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
4029{
4030 u8 nexthdr;
4031 int offset;
4032 int proto = -EINVAL;
4033 struct ipv6hdr _ipv6h;
4034 struct ipv6hdr *ip6;
4035 __be16 frag_off;
4036 struct tcphdr _tcph, *th;
4037 struct udphdr _udph, *uh;
4038 struct dccp_hdr _dccph, *dh;
4039
4040 sip->sin6_port = 0;
4041
4042 offset = skb_network_offset(skb);
4043 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4044 if (ip6 == NULL)
4045 return -EINVAL;
4046 sip->sin6_addr = ip6->saddr;
4047
4048 nexthdr = ip6->nexthdr;
4049 offset += sizeof(_ipv6h);
4050 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4051 if (offset < 0)
4052 return -EINVAL;
4053
4054 proto = nexthdr;
4055 switch (proto) {
4056 case IPPROTO_TCP:
4057 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4058 if (th != NULL)
4059 sip->sin6_port = th->source;
4060 break;
4061 case IPPROTO_UDP:
4062 case IPPROTO_UDPLITE:
4063 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4064 if (uh != NULL)
4065 sip->sin6_port = uh->source;
4066 break;
4067 case IPPROTO_DCCP:
4068 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4069 if (dh != NULL)
4070 sip->sin6_port = dh->dccph_sport;
4071 break;
4072 }
4073 return proto;
4074}
4075#endif /* CONFIG_IPV6 */
4076
4077/**
4078 * smack_from_skb - Smack data from the secmark in an skb
4079 * @skb: packet
4080 *
4081 * Returns smack_known of the secmark or NULL if that won't work.
4082 */
4083#ifdef CONFIG_NETWORK_SECMARK
4084static struct smack_known *smack_from_skb(struct sk_buff *skb)
4085{
4086 if (skb == NULL || skb->secmark == 0)
4087 return NULL;
4088
4089 return smack_from_secid(skb->secmark);
4090}
4091#else
4092static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
4093{
4094 return NULL;
4095}
4096#endif
4097
4098/**
4099 * smack_from_netlbl - Smack data from the IP options in an skb
4100 * @sk: socket data came in on
4101 * @family: address family
4102 * @skb: packet
4103 *
4104 * Find the Smack label in the IP options. If it hasn't been
4105 * added to the netlabel cache, add it here.
4106 *
4107 * Returns smack_known of the IP options or NULL if that won't work.
4108 */
4109static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
4110 struct sk_buff *skb)
4111{
4112 struct netlbl_lsm_secattr secattr;
4113 struct socket_smack *ssp = NULL;
4114 struct smack_known *skp = NULL;
4115
4116 netlbl_secattr_init(&secattr);
4117
4118 if (sk)
4119 ssp = sk->sk_security;
4120
4121 if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
4122 skp = smack_from_secattr(&secattr, ssp);
4123 if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
4124 netlbl_cache_add(skb, family, &skp->smk_netlabel);
4125 }
4126
4127 netlbl_secattr_destroy(&secattr);
4128
4129 return skp;
4130}
4131
4132/**
4133 * smack_socket_sock_rcv_skb - Smack packet delivery access check
4134 * @sk: socket
4135 * @skb: packet
4136 *
4137 * Returns 0 if the packet should be delivered, an error code otherwise
4138 */
4139static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4140{
4141 struct socket_smack *ssp = sk->sk_security;
4142 struct smack_known *skp = NULL;
4143 int rc = 0;
4144 struct smk_audit_info ad;
4145 u16 family = sk->sk_family;
4146#ifdef CONFIG_AUDIT
4147 struct lsm_network_audit net;
4148#endif
4149#if IS_ENABLED(CONFIG_IPV6)
4150 struct sockaddr_in6 sadd;
4151 int proto;
4152
4153 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4154 family = PF_INET;
4155#endif /* CONFIG_IPV6 */
4156
4157 switch (family) {
4158 case PF_INET:
4159 /*
4160 * If there is a secmark use it rather than the CIPSO label.
4161 * If there is no secmark fall back to CIPSO.
4162 * The secmark is assumed to reflect policy better.
4163 */
4164 skp = smack_from_skb(skb);
4165 if (skp == NULL) {
4166 skp = smack_from_netlbl(sk, family, skb);
4167 if (skp == NULL)
4168 skp = smack_net_ambient;
4169 }
4170
4171#ifdef CONFIG_AUDIT
4172 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4173 ad.a.u.net->family = family;
4174 ad.a.u.net->netif = skb->skb_iif;
4175 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4176#endif
4177 /*
4178 * Receiving a packet requires that the other end
4179 * be able to write here. Read access is not required.
4180 * This is the simplist possible security model
4181 * for networking.
4182 */
4183 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4184 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
4185 MAY_WRITE, rc);
4186 if (rc != 0)
4187 netlbl_skbuff_err(skb, family, rc, 0);
4188 break;
4189#if IS_ENABLED(CONFIG_IPV6)
4190 case PF_INET6:
4191 proto = smk_skb_to_addr_ipv6(skb, &sadd);
4192 if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE &&
4193 proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
4194 break;
4195#ifdef SMACK_IPV6_SECMARK_LABELING
4196 skp = smack_from_skb(skb);
4197 if (skp == NULL) {
4198 if (smk_ipv6_localhost(&sadd))
4199 break;
4200 skp = smack_ipv6host_label(&sadd);
4201 if (skp == NULL)
4202 skp = smack_net_ambient;
4203 }
4204#ifdef CONFIG_AUDIT
4205 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4206 ad.a.u.net->family = family;
4207 ad.a.u.net->netif = skb->skb_iif;
4208 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
4209#endif /* CONFIG_AUDIT */
4210 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4211 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
4212 MAY_WRITE, rc);
4213#endif /* SMACK_IPV6_SECMARK_LABELING */
4214#ifdef SMACK_IPV6_PORT_LABELING
4215 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
4216#endif /* SMACK_IPV6_PORT_LABELING */
4217 if (rc != 0)
4218 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
4219 ICMPV6_ADM_PROHIBITED, 0);
4220 break;
4221#endif /* CONFIG_IPV6 */
4222 }
4223
4224 return rc;
4225}
4226
4227/**
4228 * smack_socket_getpeersec_stream - pull in packet label
4229 * @sock: the socket
4230 * @optval: user's destination
4231 * @optlen: size thereof
4232 * @len: max thereof
4233 *
4234 * returns zero on success, an error code otherwise
4235 */
4236static int smack_socket_getpeersec_stream(struct socket *sock,
4237 sockptr_t optval, sockptr_t optlen,
4238 unsigned int len)
4239{
4240 struct socket_smack *ssp;
4241 char *rcp = "";
4242 u32 slen = 1;
4243 int rc = 0;
4244
4245 ssp = sock->sk->sk_security;
4246 if (ssp->smk_packet != NULL) {
4247 rcp = ssp->smk_packet->smk_known;
4248 slen = strlen(rcp) + 1;
4249 }
4250 if (slen > len) {
4251 rc = -ERANGE;
4252 goto out_len;
4253 }
4254
4255 if (copy_to_sockptr(optval, rcp, slen))
4256 rc = -EFAULT;
4257out_len:
4258 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
4259 rc = -EFAULT;
4260 return rc;
4261}
4262
4263
4264/**
4265 * smack_socket_getpeersec_dgram - pull in packet label
4266 * @sock: the peer socket
4267 * @skb: packet data
4268 * @secid: pointer to where to put the secid of the packet
4269 *
4270 * Sets the netlabel socket state on sk from parent
4271 */
4272static int smack_socket_getpeersec_dgram(struct socket *sock,
4273 struct sk_buff *skb, u32 *secid)
4274
4275{
4276 struct socket_smack *ssp = NULL;
4277 struct smack_known *skp;
4278 struct sock *sk = NULL;
4279 int family = PF_UNSPEC;
4280 u32 s = 0; /* 0 is the invalid secid */
4281
4282 if (skb != NULL) {
4283 if (skb->protocol == htons(ETH_P_IP))
4284 family = PF_INET;
4285#if IS_ENABLED(CONFIG_IPV6)
4286 else if (skb->protocol == htons(ETH_P_IPV6))
4287 family = PF_INET6;
4288#endif /* CONFIG_IPV6 */
4289 }
4290 if (family == PF_UNSPEC && sock != NULL)
4291 family = sock->sk->sk_family;
4292
4293 switch (family) {
4294 case PF_UNIX:
4295 ssp = sock->sk->sk_security;
4296 s = ssp->smk_out->smk_secid;
4297 break;
4298 case PF_INET:
4299 skp = smack_from_skb(skb);
4300 if (skp) {
4301 s = skp->smk_secid;
4302 break;
4303 }
4304 /*
4305 * Translate what netlabel gave us.
4306 */
4307 if (sock != NULL)
4308 sk = sock->sk;
4309 skp = smack_from_netlbl(sk, family, skb);
4310 if (skp != NULL)
4311 s = skp->smk_secid;
4312 break;
4313 case PF_INET6:
4314#ifdef SMACK_IPV6_SECMARK_LABELING
4315 skp = smack_from_skb(skb);
4316 if (skp)
4317 s = skp->smk_secid;
4318#endif
4319 break;
4320 }
4321 *secid = s;
4322 if (s == 0)
4323 return -EINVAL;
4324 return 0;
4325}
4326
4327/**
4328 * smack_sock_graft - Initialize a newly created socket with an existing sock
4329 * @sk: child sock
4330 * @parent: parent socket
4331 *
4332 * Set the smk_{in,out} state of an existing sock based on the process that
4333 * is creating the new socket.
4334 */
4335static void smack_sock_graft(struct sock *sk, struct socket *parent)
4336{
4337 struct socket_smack *ssp;
4338 struct smack_known *skp = smk_of_current();
4339
4340 if (sk == NULL ||
4341 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4342 return;
4343
4344 ssp = sk->sk_security;
4345 ssp->smk_in = skp;
4346 ssp->smk_out = skp;
4347 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4348}
4349
4350/**
4351 * smack_inet_conn_request - Smack access check on connect
4352 * @sk: socket involved
4353 * @skb: packet
4354 * @req: unused
4355 *
4356 * Returns 0 if a task with the packet label could write to
4357 * the socket, otherwise an error code
4358 */
4359static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
4360 struct request_sock *req)
4361{
4362 u16 family = sk->sk_family;
4363 struct smack_known *skp;
4364 struct socket_smack *ssp = sk->sk_security;
4365 struct sockaddr_in addr;
4366 struct iphdr *hdr;
4367 struct smack_known *hskp;
4368 int rc;
4369 struct smk_audit_info ad;
4370#ifdef CONFIG_AUDIT
4371 struct lsm_network_audit net;
4372#endif
4373
4374#if IS_ENABLED(CONFIG_IPV6)
4375 if (family == PF_INET6) {
4376 /*
4377 * Handle mapped IPv4 packets arriving
4378 * via IPv6 sockets. Don't set up netlabel
4379 * processing on IPv6.
4380 */
4381 if (skb->protocol == htons(ETH_P_IP))
4382 family = PF_INET;
4383 else
4384 return 0;
4385 }
4386#endif /* CONFIG_IPV6 */
4387
4388 /*
4389 * If there is a secmark use it rather than the CIPSO label.
4390 * If there is no secmark fall back to CIPSO.
4391 * The secmark is assumed to reflect policy better.
4392 */
4393 skp = smack_from_skb(skb);
4394 if (skp == NULL) {
4395 skp = smack_from_netlbl(sk, family, skb);
4396 if (skp == NULL)
4397 skp = &smack_known_huh;
4398 }
4399
4400#ifdef CONFIG_AUDIT
4401 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4402 ad.a.u.net->family = family;
4403 ad.a.u.net->netif = skb->skb_iif;
4404 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4405#endif
4406 /*
4407 * Receiving a packet requires that the other end be able to write
4408 * here. Read access is not required.
4409 */
4410 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4411 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4412 if (rc != 0)
4413 return rc;
4414
4415 /*
4416 * Save the peer's label in the request_sock so we can later setup
4417 * smk_packet in the child socket so that SO_PEERCRED can report it.
4418 */
4419 req->peer_secid = skp->smk_secid;
4420
4421 /*
4422 * We need to decide if we want to label the incoming connection here
4423 * if we do we only need to label the request_sock and the stack will
4424 * propagate the wire-label to the sock when it is created.
4425 */
4426 hdr = ip_hdr(skb);
4427 addr.sin_addr.s_addr = hdr->saddr;
4428 rcu_read_lock();
4429 hskp = smack_ipv4host_label(&addr);
4430 rcu_read_unlock();
4431
4432 if (hskp == NULL)
4433 rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4434 else
4435 netlbl_req_delattr(req);
4436
4437 return rc;
4438}
4439
4440/**
4441 * smack_inet_csk_clone - Copy the connection information to the new socket
4442 * @sk: the new socket
4443 * @req: the connection's request_sock
4444 *
4445 * Transfer the connection's peer label to the newly created socket.
4446 */
4447static void smack_inet_csk_clone(struct sock *sk,
4448 const struct request_sock *req)
4449{
4450 struct socket_smack *ssp = sk->sk_security;
4451 struct smack_known *skp;
4452
4453 if (req->peer_secid != 0) {
4454 skp = smack_from_secid(req->peer_secid);
4455 ssp->smk_packet = skp;
4456 } else
4457 ssp->smk_packet = NULL;
4458}
4459
4460/*
4461 * Key management security hooks
4462 *
4463 * Casey has not tested key support very heavily.
4464 * The permission check is most likely too restrictive.
4465 * If you care about keys please have a look.
4466 */
4467#ifdef CONFIG_KEYS
4468
4469/**
4470 * smack_key_alloc - Set the key security blob
4471 * @key: object
4472 * @cred: the credentials to use
4473 * @flags: unused
4474 *
4475 * No allocation required
4476 *
4477 * Returns 0
4478 */
4479static int smack_key_alloc(struct key *key, const struct cred *cred,
4480 unsigned long flags)
4481{
4482 struct smack_known *skp = smk_of_task(smack_cred(cred));
4483
4484 key->security = skp;
4485 return 0;
4486}
4487
4488/**
4489 * smack_key_free - Clear the key security blob
4490 * @key: the object
4491 *
4492 * Clear the blob pointer
4493 */
4494static void smack_key_free(struct key *key)
4495{
4496 key->security = NULL;
4497}
4498
4499/**
4500 * smack_key_permission - Smack access on a key
4501 * @key_ref: gets to the object
4502 * @cred: the credentials to use
4503 * @need_perm: requested key permission
4504 *
4505 * Return 0 if the task has read and write to the object,
4506 * an error code otherwise
4507 */
4508static int smack_key_permission(key_ref_t key_ref,
4509 const struct cred *cred,
4510 enum key_need_perm need_perm)
4511{
4512 struct key *keyp;
4513 struct smk_audit_info ad;
4514 struct smack_known *tkp = smk_of_task(smack_cred(cred));
4515 int request = 0;
4516 int rc;
4517
4518 /*
4519 * Validate requested permissions
4520 */
4521 switch (need_perm) {
4522 case KEY_NEED_READ:
4523 case KEY_NEED_SEARCH:
4524 case KEY_NEED_VIEW:
4525 request |= MAY_READ;
4526 break;
4527 case KEY_NEED_WRITE:
4528 case KEY_NEED_LINK:
4529 case KEY_NEED_SETATTR:
4530 request |= MAY_WRITE;
4531 break;
4532 case KEY_NEED_UNSPECIFIED:
4533 case KEY_NEED_UNLINK:
4534 case KEY_SYSADMIN_OVERRIDE:
4535 case KEY_AUTHTOKEN_OVERRIDE:
4536 case KEY_DEFER_PERM_CHECK:
4537 return 0;
4538 default:
4539 return -EINVAL;
4540 }
4541
4542 keyp = key_ref_to_ptr(key_ref);
4543 if (keyp == NULL)
4544 return -EINVAL;
4545 /*
4546 * If the key hasn't been initialized give it access so that
4547 * it may do so.
4548 */
4549 if (keyp->security == NULL)
4550 return 0;
4551 /*
4552 * This should not occur
4553 */
4554 if (tkp == NULL)
4555 return -EACCES;
4556
4557 if (smack_privileged(CAP_MAC_OVERRIDE))
4558 return 0;
4559
4560#ifdef CONFIG_AUDIT
4561 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4562 ad.a.u.key_struct.key = keyp->serial;
4563 ad.a.u.key_struct.key_desc = keyp->description;
4564#endif
4565 rc = smk_access(tkp, keyp->security, request, &ad);
4566 rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
4567 return rc;
4568}
4569
4570/*
4571 * smack_key_getsecurity - Smack label tagging the key
4572 * @key points to the key to be queried
4573 * @_buffer points to a pointer that should be set to point to the
4574 * resulting string (if no label or an error occurs).
4575 * Return the length of the string (including terminating NUL) or -ve if
4576 * an error.
4577 * May also return 0 (and a NULL buffer pointer) if there is no label.
4578 */
4579static int smack_key_getsecurity(struct key *key, char **_buffer)
4580{
4581 struct smack_known *skp = key->security;
4582 size_t length;
4583 char *copy;
4584
4585 if (key->security == NULL) {
4586 *_buffer = NULL;
4587 return 0;
4588 }
4589
4590 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4591 if (copy == NULL)
4592 return -ENOMEM;
4593 length = strlen(copy) + 1;
4594
4595 *_buffer = copy;
4596 return length;
4597}
4598
4599
4600#ifdef CONFIG_KEY_NOTIFICATIONS
4601/**
4602 * smack_watch_key - Smack access to watch a key for notifications.
4603 * @key: The key to be watched
4604 *
4605 * Return 0 if the @watch->cred has permission to read from the key object and
4606 * an error otherwise.
4607 */
4608static int smack_watch_key(struct key *key)
4609{
4610 struct smk_audit_info ad;
4611 struct smack_known *tkp = smk_of_current();
4612 int rc;
4613
4614 if (key == NULL)
4615 return -EINVAL;
4616 /*
4617 * If the key hasn't been initialized give it access so that
4618 * it may do so.
4619 */
4620 if (key->security == NULL)
4621 return 0;
4622 /*
4623 * This should not occur
4624 */
4625 if (tkp == NULL)
4626 return -EACCES;
4627
4628 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
4629 return 0;
4630
4631#ifdef CONFIG_AUDIT
4632 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4633 ad.a.u.key_struct.key = key->serial;
4634 ad.a.u.key_struct.key_desc = key->description;
4635#endif
4636 rc = smk_access(tkp, key->security, MAY_READ, &ad);
4637 rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
4638 return rc;
4639}
4640#endif /* CONFIG_KEY_NOTIFICATIONS */
4641#endif /* CONFIG_KEYS */
4642
4643#ifdef CONFIG_WATCH_QUEUE
4644/**
4645 * smack_post_notification - Smack access to post a notification to a queue
4646 * @w_cred: The credentials of the watcher.
4647 * @cred: The credentials of the event source (may be NULL).
4648 * @n: The notification message to be posted.
4649 */
4650static int smack_post_notification(const struct cred *w_cred,
4651 const struct cred *cred,
4652 struct watch_notification *n)
4653{
4654 struct smk_audit_info ad;
4655 struct smack_known *subj, *obj;
4656 int rc;
4657
4658 /* Always let maintenance notifications through. */
4659 if (n->type == WATCH_TYPE_META)
4660 return 0;
4661
4662 if (!cred)
4663 return 0;
4664 subj = smk_of_task(smack_cred(cred));
4665 obj = smk_of_task(smack_cred(w_cred));
4666
4667 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
4668 rc = smk_access(subj, obj, MAY_WRITE, &ad);
4669 rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
4670 return rc;
4671}
4672#endif /* CONFIG_WATCH_QUEUE */
4673
4674/*
4675 * Smack Audit hooks
4676 *
4677 * Audit requires a unique representation of each Smack specific
4678 * rule. This unique representation is used to distinguish the
4679 * object to be audited from remaining kernel objects and also
4680 * works as a glue between the audit hooks.
4681 *
4682 * Since repository entries are added but never deleted, we'll use
4683 * the smack_known label address related to the given audit rule as
4684 * the needed unique representation. This also better fits the smack
4685 * model where nearly everything is a label.
4686 */
4687#ifdef CONFIG_AUDIT
4688
4689/**
4690 * smack_audit_rule_init - Initialize a smack audit rule
4691 * @field: audit rule fields given from user-space (audit.h)
4692 * @op: required testing operator (=, !=, >, <, ...)
4693 * @rulestr: smack label to be audited
4694 * @vrule: pointer to save our own audit rule representation
4695 *
4696 * Prepare to audit cases where (@field @op @rulestr) is true.
4697 * The label to be audited is created if necessay.
4698 */
4699static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
4700{
4701 struct smack_known *skp;
4702 char **rule = (char **)vrule;
4703 *rule = NULL;
4704
4705 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4706 return -EINVAL;
4707
4708 if (op != Audit_equal && op != Audit_not_equal)
4709 return -EINVAL;
4710
4711 skp = smk_import_entry(rulestr, 0);
4712 if (IS_ERR(skp))
4713 return PTR_ERR(skp);
4714
4715 *rule = skp->smk_known;
4716
4717 return 0;
4718}
4719
4720/**
4721 * smack_audit_rule_known - Distinguish Smack audit rules
4722 * @krule: rule of interest, in Audit kernel representation format
4723 *
4724 * This is used to filter Smack rules from remaining Audit ones.
4725 * If it's proved that this rule belongs to us, the
4726 * audit_rule_match hook will be called to do the final judgement.
4727 */
4728static int smack_audit_rule_known(struct audit_krule *krule)
4729{
4730 struct audit_field *f;
4731 int i;
4732
4733 for (i = 0; i < krule->field_count; i++) {
4734 f = &krule->fields[i];
4735
4736 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4737 return 1;
4738 }
4739
4740 return 0;
4741}
4742
4743/**
4744 * smack_audit_rule_match - Audit given object ?
4745 * @secid: security id for identifying the object to test
4746 * @field: audit rule flags given from user-space
4747 * @op: required testing operator
4748 * @vrule: smack internal rule presentation
4749 *
4750 * The core Audit hook. It's used to take the decision of
4751 * whether to audit or not to audit a given object.
4752 */
4753static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule)
4754{
4755 struct smack_known *skp;
4756 char *rule = vrule;
4757
4758 if (unlikely(!rule)) {
4759 WARN_ONCE(1, "Smack: missing rule\n");
4760 return -ENOENT;
4761 }
4762
4763 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4764 return 0;
4765
4766 skp = smack_from_secid(secid);
4767
4768 /*
4769 * No need to do string comparisons. If a match occurs,
4770 * both pointers will point to the same smack_known
4771 * label.
4772 */
4773 if (op == Audit_equal)
4774 return (rule == skp->smk_known);
4775 if (op == Audit_not_equal)
4776 return (rule != skp->smk_known);
4777
4778 return 0;
4779}
4780
4781/*
4782 * There is no need for a smack_audit_rule_free hook.
4783 * No memory was allocated.
4784 */
4785
4786#endif /* CONFIG_AUDIT */
4787
4788/**
4789 * smack_ismaclabel - check if xattr @name references a smack MAC label
4790 * @name: Full xattr name to check.
4791 */
4792static int smack_ismaclabel(const char *name)
4793{
4794 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4795}
4796
4797
4798/**
4799 * smack_secid_to_secctx - return the smack label for a secid
4800 * @secid: incoming integer
4801 * @secdata: destination
4802 * @seclen: how long it is
4803 *
4804 * Exists for networking code.
4805 */
4806static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4807{
4808 struct smack_known *skp = smack_from_secid(secid);
4809
4810 if (secdata)
4811 *secdata = skp->smk_known;
4812 *seclen = strlen(skp->smk_known);
4813 return 0;
4814}
4815
4816/**
4817 * smack_secctx_to_secid - return the secid for a smack label
4818 * @secdata: smack label
4819 * @seclen: how long result is
4820 * @secid: outgoing integer
4821 *
4822 * Exists for audit and networking code.
4823 */
4824static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4825{
4826 struct smack_known *skp = smk_find_entry(secdata);
4827
4828 if (skp)
4829 *secid = skp->smk_secid;
4830 else
4831 *secid = 0;
4832 return 0;
4833}
4834
4835/*
4836 * There used to be a smack_release_secctx hook
4837 * that did nothing back when hooks were in a vector.
4838 * Now that there's a list such a hook adds cost.
4839 */
4840
4841static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4842{
4843 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
4844 ctxlen, 0);
4845}
4846
4847static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4848{
4849 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SMACK,
4850 ctx, ctxlen, 0);
4851}
4852
4853static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4854{
4855 struct smack_known *skp = smk_of_inode(inode);
4856
4857 *ctx = skp->smk_known;
4858 *ctxlen = strlen(skp->smk_known);
4859 return 0;
4860}
4861
4862static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
4863{
4864
4865 struct task_smack *tsp;
4866 struct smack_known *skp;
4867 struct inode_smack *isp;
4868 struct cred *new_creds = *new;
4869
4870 if (new_creds == NULL) {
4871 new_creds = prepare_creds();
4872 if (new_creds == NULL)
4873 return -ENOMEM;
4874 }
4875
4876 tsp = smack_cred(new_creds);
4877
4878 /*
4879 * Get label from overlay inode and set it in create_sid
4880 */
4881 isp = smack_inode(d_inode(dentry));
4882 skp = isp->smk_inode;
4883 tsp->smk_task = skp;
4884 *new = new_creds;
4885 return 0;
4886}
4887
4888static int smack_inode_copy_up_xattr(const char *name)
4889{
4890 /*
4891 * Return 1 if this is the smack access Smack attribute.
4892 */
4893 if (strcmp(name, XATTR_NAME_SMACK) == 0)
4894 return 1;
4895
4896 return -EOPNOTSUPP;
4897}
4898
4899static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
4900 struct qstr *name,
4901 const struct cred *old,
4902 struct cred *new)
4903{
4904 struct task_smack *otsp = smack_cred(old);
4905 struct task_smack *ntsp = smack_cred(new);
4906 struct inode_smack *isp;
4907 int may;
4908
4909 /*
4910 * Use the process credential unless all of
4911 * the transmuting criteria are met
4912 */
4913 ntsp->smk_task = otsp->smk_task;
4914
4915 /*
4916 * the attribute of the containing directory
4917 */
4918 isp = smack_inode(d_inode(dentry->d_parent));
4919
4920 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
4921 rcu_read_lock();
4922 may = smk_access_entry(otsp->smk_task->smk_known,
4923 isp->smk_inode->smk_known,
4924 &otsp->smk_task->smk_rules);
4925 rcu_read_unlock();
4926
4927 /*
4928 * If the directory is transmuting and the rule
4929 * providing access is transmuting use the containing
4930 * directory label instead of the process label.
4931 */
4932 if (may > 0 && (may & MAY_TRANSMUTE)) {
4933 ntsp->smk_task = isp->smk_inode;
4934 ntsp->smk_transmuted = ntsp->smk_task;
4935 }
4936 }
4937 return 0;
4938}
4939
4940#ifdef CONFIG_IO_URING
4941/**
4942 * smack_uring_override_creds - Is io_uring cred override allowed?
4943 * @new: the target creds
4944 *
4945 * Check to see if the current task is allowed to override it's credentials
4946 * to service an io_uring operation.
4947 */
4948static int smack_uring_override_creds(const struct cred *new)
4949{
4950 struct task_smack *tsp = smack_cred(current_cred());
4951 struct task_smack *nsp = smack_cred(new);
4952
4953 /*
4954 * Allow the degenerate case where the new Smack value is
4955 * the same as the current Smack value.
4956 */
4957 if (tsp->smk_task == nsp->smk_task)
4958 return 0;
4959
4960 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
4961 return 0;
4962
4963 return -EPERM;
4964}
4965
4966/**
4967 * smack_uring_sqpoll - check if a io_uring polling thread can be created
4968 *
4969 * Check to see if the current task is allowed to create a new io_uring
4970 * kernel polling thread.
4971 */
4972static int smack_uring_sqpoll(void)
4973{
4974 if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
4975 return 0;
4976
4977 return -EPERM;
4978}
4979
4980/**
4981 * smack_uring_cmd - check on file operations for io_uring
4982 * @ioucmd: the command in question
4983 *
4984 * Make a best guess about whether a io_uring "command" should
4985 * be allowed. Use the same logic used for determining if the
4986 * file could be opened for read in the absence of better criteria.
4987 */
4988static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
4989{
4990 struct file *file = ioucmd->file;
4991 struct smk_audit_info ad;
4992 struct task_smack *tsp;
4993 struct inode *inode;
4994 int rc;
4995
4996 if (!file)
4997 return -EINVAL;
4998
4999 tsp = smack_cred(file->f_cred);
5000 inode = file_inode(file);
5001
5002 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
5003 smk_ad_setfield_u_fs_path(&ad, file->f_path);
5004 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
5005 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
5006
5007 return rc;
5008}
5009
5010#endif /* CONFIG_IO_URING */
5011
5012struct lsm_blob_sizes smack_blob_sizes __ro_after_init = {
5013 .lbs_cred = sizeof(struct task_smack),
5014 .lbs_file = sizeof(struct smack_known *),
5015 .lbs_inode = sizeof(struct inode_smack),
5016 .lbs_ipc = sizeof(struct smack_known *),
5017 .lbs_msg_msg = sizeof(struct smack_known *),
5018 .lbs_superblock = sizeof(struct superblock_smack),
5019 .lbs_xattr_count = SMACK_INODE_INIT_XATTRS,
5020};
5021
5022static const struct lsm_id smack_lsmid = {
5023 .name = "smack",
5024 .id = LSM_ID_SMACK,
5025};
5026
5027static struct security_hook_list smack_hooks[] __ro_after_init = {
5028 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
5029 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
5030 LSM_HOOK_INIT(syslog, smack_syslog),
5031
5032 LSM_HOOK_INIT(fs_context_submount, smack_fs_context_submount),
5033 LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
5034 LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
5035
5036 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
5037 LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
5038 LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
5039 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
5040 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
5041
5042 LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
5043
5044 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
5045 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
5046 LSM_HOOK_INIT(inode_link, smack_inode_link),
5047 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
5048 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
5049 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
5050 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
5051 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
5052 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
5053 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
5054 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
5055 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
5056 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
5057 LSM_HOOK_INIT(inode_set_acl, smack_inode_set_acl),
5058 LSM_HOOK_INIT(inode_get_acl, smack_inode_get_acl),
5059 LSM_HOOK_INIT(inode_remove_acl, smack_inode_remove_acl),
5060 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
5061 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
5062 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
5063 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
5064
5065 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
5066 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
5067 LSM_HOOK_INIT(file_ioctl_compat, smack_file_ioctl),
5068 LSM_HOOK_INIT(file_lock, smack_file_lock),
5069 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
5070 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
5071 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
5072 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
5073 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
5074 LSM_HOOK_INIT(file_receive, smack_file_receive),
5075
5076 LSM_HOOK_INIT(file_open, smack_file_open),
5077
5078 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
5079 LSM_HOOK_INIT(cred_free, smack_cred_free),
5080 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
5081 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
5082 LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
5083 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
5084 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
5085 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
5086 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
5087 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
5088 LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj),
5089 LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj),
5090 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
5091 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
5092 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
5093 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
5094 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
5095 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
5096 LSM_HOOK_INIT(task_kill, smack_task_kill),
5097 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
5098
5099 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
5100 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
5101
5102 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
5103
5104 LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
5105 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
5106 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
5107 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
5108 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
5109
5110 LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
5111 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
5112 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
5113 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
5114
5115 LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
5116 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
5117 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
5118 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
5119
5120 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
5121
5122 LSM_HOOK_INIT(getselfattr, smack_getselfattr),
5123 LSM_HOOK_INIT(setselfattr, smack_setselfattr),
5124 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
5125 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
5126
5127 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
5128 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
5129
5130 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
5131 LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair),
5132#ifdef SMACK_IPV6_PORT_LABELING
5133 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
5134#endif
5135 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
5136 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
5137 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
5138 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
5139 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
5140 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
5141 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
5142 LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security),
5143 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
5144 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
5145 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
5146
5147 /* key management security hooks */
5148#ifdef CONFIG_KEYS
5149 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
5150 LSM_HOOK_INIT(key_free, smack_key_free),
5151 LSM_HOOK_INIT(key_permission, smack_key_permission),
5152 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
5153#ifdef CONFIG_KEY_NOTIFICATIONS
5154 LSM_HOOK_INIT(watch_key, smack_watch_key),
5155#endif
5156#endif /* CONFIG_KEYS */
5157
5158#ifdef CONFIG_WATCH_QUEUE
5159 LSM_HOOK_INIT(post_notification, smack_post_notification),
5160#endif
5161
5162 /* Audit hooks */
5163#ifdef CONFIG_AUDIT
5164 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
5165 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
5166 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
5167#endif /* CONFIG_AUDIT */
5168
5169 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
5170 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
5171 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
5172 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
5173 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
5174 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
5175 LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
5176 LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
5177 LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
5178#ifdef CONFIG_IO_URING
5179 LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
5180 LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
5181 LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
5182#endif
5183};
5184
5185
5186static __init void init_smack_known_list(void)
5187{
5188 /*
5189 * Initialize rule list locks
5190 */
5191 mutex_init(&smack_known_huh.smk_rules_lock);
5192 mutex_init(&smack_known_hat.smk_rules_lock);
5193 mutex_init(&smack_known_floor.smk_rules_lock);
5194 mutex_init(&smack_known_star.smk_rules_lock);
5195 mutex_init(&smack_known_web.smk_rules_lock);
5196 /*
5197 * Initialize rule lists
5198 */
5199 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
5200 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
5201 INIT_LIST_HEAD(&smack_known_star.smk_rules);
5202 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
5203 INIT_LIST_HEAD(&smack_known_web.smk_rules);
5204 /*
5205 * Create the known labels list
5206 */
5207 smk_insert_entry(&smack_known_huh);
5208 smk_insert_entry(&smack_known_hat);
5209 smk_insert_entry(&smack_known_star);
5210 smk_insert_entry(&smack_known_floor);
5211 smk_insert_entry(&smack_known_web);
5212}
5213
5214/**
5215 * smack_init - initialize the smack system
5216 *
5217 * Returns 0 on success, -ENOMEM is there's no memory
5218 */
5219static __init int smack_init(void)
5220{
5221 struct cred *cred = (struct cred *) current->cred;
5222 struct task_smack *tsp;
5223
5224 smack_rule_cache = KMEM_CACHE(smack_rule, 0);
5225 if (!smack_rule_cache)
5226 return -ENOMEM;
5227
5228 /*
5229 * Set the security state for the initial task.
5230 */
5231 tsp = smack_cred(cred);
5232 init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
5233
5234 /*
5235 * Register with LSM
5236 */
5237 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
5238 smack_enabled = 1;
5239
5240 pr_info("Smack: Initializing.\n");
5241#ifdef CONFIG_SECURITY_SMACK_NETFILTER
5242 pr_info("Smack: Netfilter enabled.\n");
5243#endif
5244#ifdef SMACK_IPV6_PORT_LABELING
5245 pr_info("Smack: IPv6 port labeling enabled.\n");
5246#endif
5247#ifdef SMACK_IPV6_SECMARK_LABELING
5248 pr_info("Smack: IPv6 Netfilter enabled.\n");
5249#endif
5250
5251 /* initialize the smack_known_list */
5252 init_smack_known_list();
5253
5254 return 0;
5255}
5256
5257/*
5258 * Smack requires early initialization in order to label
5259 * all processes and objects when they are created.
5260 */
5261DEFINE_LSM(smack) = {
5262 .name = "smack",
5263 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
5264 .blobs = &smack_blob_sizes,
5265 .init = smack_init,
5266};