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