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/slab.h>
31 #include <linux/mutex.h>
32 #include <linux/pipe_fs_i.h>
33 #include <net/netlabel.h>
34 #include <net/cipso_ipv4.h>
35 #include <linux/audit.h>
36 #include <linux/magic.h>
37 #include <linux/dcache.h>
38 #include <linux/personality.h>
39 #include <linux/msg.h>
40 #include <linux/shm.h>
41 #include <linux/binfmts.h>
42 #include "smack.h"
43
44 #define task_security(task) (task_cred_xxx((task), security))
45
46 #define TRANS_TRUE "TRUE"
47 #define TRANS_TRUE_SIZE 4
48
49 /**
50 * smk_fetch - Fetch the smack label from a file.
51 * @ip: a pointer to the inode
52 * @dp: a pointer to the dentry
53 *
54 * Returns a pointer to the master list entry for the Smack label
55 * or NULL if there was no label to fetch.
56 */
smk_fetch(const char * name,struct inode * ip,struct dentry * dp)57 static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp)
58 {
59 int rc;
60 char in[SMK_LABELLEN];
61
62 if (ip->i_op->getxattr == NULL)
63 return NULL;
64
65 rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN);
66 if (rc < 0)
67 return NULL;
68
69 return smk_import(in, rc);
70 }
71
72 /**
73 * new_inode_smack - allocate an inode security blob
74 * @smack: a pointer to the Smack label to use in the blob
75 *
76 * Returns the new blob or NULL if there's no memory available
77 */
new_inode_smack(char * smack)78 struct inode_smack *new_inode_smack(char *smack)
79 {
80 struct inode_smack *isp;
81
82 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
83 if (isp == NULL)
84 return NULL;
85
86 isp->smk_inode = smack;
87 isp->smk_flags = 0;
88 mutex_init(&isp->smk_lock);
89
90 return isp;
91 }
92
93 /**
94 * new_task_smack - allocate a task security blob
95 * @smack: a pointer to the Smack label to use in the blob
96 *
97 * Returns the new blob or NULL if there's no memory available
98 */
new_task_smack(char * task,char * forked,gfp_t gfp)99 static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp)
100 {
101 struct task_smack *tsp;
102
103 tsp = kzalloc(sizeof(struct task_smack), gfp);
104 if (tsp == NULL)
105 return NULL;
106
107 tsp->smk_task = task;
108 tsp->smk_forked = forked;
109 INIT_LIST_HEAD(&tsp->smk_rules);
110 mutex_init(&tsp->smk_rules_lock);
111
112 return tsp;
113 }
114
115 /**
116 * smk_copy_rules - copy a rule set
117 * @nhead - new rules header pointer
118 * @ohead - old rules header pointer
119 *
120 * Returns 0 on success, -ENOMEM on error
121 */
smk_copy_rules(struct list_head * nhead,struct list_head * ohead,gfp_t gfp)122 static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
123 gfp_t gfp)
124 {
125 struct smack_rule *nrp;
126 struct smack_rule *orp;
127 int rc = 0;
128
129 INIT_LIST_HEAD(nhead);
130
131 list_for_each_entry_rcu(orp, ohead, list) {
132 nrp = kzalloc(sizeof(struct smack_rule), gfp);
133 if (nrp == NULL) {
134 rc = -ENOMEM;
135 break;
136 }
137 *nrp = *orp;
138 list_add_rcu(&nrp->list, nhead);
139 }
140 return rc;
141 }
142
143 /*
144 * LSM hooks.
145 * We he, that is fun!
146 */
147
148 /**
149 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
150 * @ctp: child task pointer
151 * @mode: ptrace attachment mode
152 *
153 * Returns 0 if access is OK, an error code otherwise
154 *
155 * Do the capability checks, and require read and write.
156 */
smack_ptrace_access_check(struct task_struct * ctp,unsigned int mode)157 static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
158 {
159 int rc;
160 struct smk_audit_info ad;
161 char *tsp;
162
163 rc = cap_ptrace_access_check(ctp, mode);
164 if (rc != 0)
165 return rc;
166
167 tsp = smk_of_task(task_security(ctp));
168 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
169 smk_ad_setfield_u_tsk(&ad, ctp);
170
171 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
172 return rc;
173 }
174
175 /**
176 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
177 * @ptp: parent task pointer
178 *
179 * Returns 0 if access is OK, an error code otherwise
180 *
181 * Do the capability checks, and require read and write.
182 */
smack_ptrace_traceme(struct task_struct * ptp)183 static int smack_ptrace_traceme(struct task_struct *ptp)
184 {
185 int rc;
186 struct smk_audit_info ad;
187 char *tsp;
188
189 rc = cap_ptrace_traceme(ptp);
190 if (rc != 0)
191 return rc;
192
193 tsp = smk_of_task(task_security(ptp));
194 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
195 smk_ad_setfield_u_tsk(&ad, ptp);
196
197 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
198 return rc;
199 }
200
201 /**
202 * smack_syslog - Smack approval on syslog
203 * @type: message type
204 *
205 * Require that the task has the floor label
206 *
207 * Returns 0 on success, error code otherwise.
208 */
smack_syslog(int typefrom_file)209 static int smack_syslog(int typefrom_file)
210 {
211 int rc = 0;
212 char *sp = smk_of_current();
213
214 if (capable(CAP_MAC_OVERRIDE))
215 return 0;
216
217 if (sp != smack_known_floor.smk_known)
218 rc = -EACCES;
219
220 return rc;
221 }
222
223
224 /*
225 * Superblock Hooks.
226 */
227
228 /**
229 * smack_sb_alloc_security - allocate a superblock blob
230 * @sb: the superblock getting the blob
231 *
232 * Returns 0 on success or -ENOMEM on error.
233 */
smack_sb_alloc_security(struct super_block * sb)234 static int smack_sb_alloc_security(struct super_block *sb)
235 {
236 struct superblock_smack *sbsp;
237
238 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
239
240 if (sbsp == NULL)
241 return -ENOMEM;
242
243 sbsp->smk_root = smack_known_floor.smk_known;
244 sbsp->smk_default = smack_known_floor.smk_known;
245 sbsp->smk_floor = smack_known_floor.smk_known;
246 sbsp->smk_hat = smack_known_hat.smk_known;
247 sbsp->smk_initialized = 0;
248 spin_lock_init(&sbsp->smk_sblock);
249
250 sb->s_security = sbsp;
251
252 return 0;
253 }
254
255 /**
256 * smack_sb_free_security - free a superblock blob
257 * @sb: the superblock getting the blob
258 *
259 */
smack_sb_free_security(struct super_block * sb)260 static void smack_sb_free_security(struct super_block *sb)
261 {
262 kfree(sb->s_security);
263 sb->s_security = NULL;
264 }
265
266 /**
267 * smack_sb_copy_data - copy mount options data for processing
268 * @orig: where to start
269 * @smackopts: mount options string
270 *
271 * Returns 0 on success or -ENOMEM on error.
272 *
273 * Copy the Smack specific mount options out of the mount
274 * options list.
275 */
smack_sb_copy_data(char * orig,char * smackopts)276 static int smack_sb_copy_data(char *orig, char *smackopts)
277 {
278 char *cp, *commap, *otheropts, *dp;
279
280 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
281 if (otheropts == NULL)
282 return -ENOMEM;
283
284 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
285 if (strstr(cp, SMK_FSDEFAULT) == cp)
286 dp = smackopts;
287 else if (strstr(cp, SMK_FSFLOOR) == cp)
288 dp = smackopts;
289 else if (strstr(cp, SMK_FSHAT) == cp)
290 dp = smackopts;
291 else if (strstr(cp, SMK_FSROOT) == cp)
292 dp = smackopts;
293 else
294 dp = otheropts;
295
296 commap = strchr(cp, ',');
297 if (commap != NULL)
298 *commap = '\0';
299
300 if (*dp != '\0')
301 strcat(dp, ",");
302 strcat(dp, cp);
303 }
304
305 strcpy(orig, otheropts);
306 free_page((unsigned long)otheropts);
307
308 return 0;
309 }
310
311 /**
312 * smack_sb_kern_mount - Smack specific mount processing
313 * @sb: the file system superblock
314 * @flags: the mount flags
315 * @data: the smack mount options
316 *
317 * Returns 0 on success, an error code on failure
318 */
smack_sb_kern_mount(struct super_block * sb,int flags,void * data)319 static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
320 {
321 struct dentry *root = sb->s_root;
322 struct inode *inode = root->d_inode;
323 struct superblock_smack *sp = sb->s_security;
324 struct inode_smack *isp;
325 char *op;
326 char *commap;
327 char *nsp;
328
329 spin_lock(&sp->smk_sblock);
330 if (sp->smk_initialized != 0) {
331 spin_unlock(&sp->smk_sblock);
332 return 0;
333 }
334 sp->smk_initialized = 1;
335 spin_unlock(&sp->smk_sblock);
336
337 for (op = data; op != NULL; op = commap) {
338 commap = strchr(op, ',');
339 if (commap != NULL)
340 *commap++ = '\0';
341
342 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
343 op += strlen(SMK_FSHAT);
344 nsp = smk_import(op, 0);
345 if (nsp != NULL)
346 sp->smk_hat = nsp;
347 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
348 op += strlen(SMK_FSFLOOR);
349 nsp = smk_import(op, 0);
350 if (nsp != NULL)
351 sp->smk_floor = nsp;
352 } else if (strncmp(op, SMK_FSDEFAULT,
353 strlen(SMK_FSDEFAULT)) == 0) {
354 op += strlen(SMK_FSDEFAULT);
355 nsp = smk_import(op, 0);
356 if (nsp != NULL)
357 sp->smk_default = nsp;
358 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
359 op += strlen(SMK_FSROOT);
360 nsp = smk_import(op, 0);
361 if (nsp != NULL)
362 sp->smk_root = nsp;
363 }
364 }
365
366 /*
367 * Initialize the root inode.
368 */
369 isp = inode->i_security;
370 if (isp == NULL)
371 inode->i_security = new_inode_smack(sp->smk_root);
372 else
373 isp->smk_inode = sp->smk_root;
374
375 return 0;
376 }
377
378 /**
379 * smack_sb_statfs - Smack check on statfs
380 * @dentry: identifies the file system in question
381 *
382 * Returns 0 if current can read the floor of the filesystem,
383 * and error code otherwise
384 */
smack_sb_statfs(struct dentry * dentry)385 static int smack_sb_statfs(struct dentry *dentry)
386 {
387 struct superblock_smack *sbp = dentry->d_sb->s_security;
388 int rc;
389 struct smk_audit_info ad;
390
391 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
392 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
393
394 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
395 return rc;
396 }
397
398 /**
399 * smack_sb_mount - Smack check for mounting
400 * @dev_name: unused
401 * @path: mount point
402 * @type: unused
403 * @flags: unused
404 * @data: unused
405 *
406 * Returns 0 if current can write the floor of the filesystem
407 * being mounted on, an error code otherwise.
408 */
smack_sb_mount(const char * dev_name,struct path * path,const char * type,unsigned long flags,void * data)409 static int smack_sb_mount(const char *dev_name, struct path *path,
410 const char *type, unsigned long flags, void *data)
411 {
412 struct superblock_smack *sbp = path->dentry->d_sb->s_security;
413 struct smk_audit_info ad;
414
415 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
416 smk_ad_setfield_u_fs_path(&ad, *path);
417
418 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
419 }
420
421 /**
422 * smack_sb_umount - Smack check for unmounting
423 * @mnt: file system to unmount
424 * @flags: unused
425 *
426 * Returns 0 if current can write the floor of the filesystem
427 * being unmounted, an error code otherwise.
428 */
smack_sb_umount(struct vfsmount * mnt,int flags)429 static int smack_sb_umount(struct vfsmount *mnt, int flags)
430 {
431 struct superblock_smack *sbp;
432 struct smk_audit_info ad;
433 struct path path;
434
435 path.dentry = mnt->mnt_root;
436 path.mnt = mnt;
437
438 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
439 smk_ad_setfield_u_fs_path(&ad, path);
440
441 sbp = path.dentry->d_sb->s_security;
442 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
443 }
444
445 /*
446 * BPRM hooks
447 */
448
449 /**
450 * smack_bprm_set_creds - set creds for exec
451 * @bprm: the exec information
452 *
453 * Returns 0 if it gets a blob, -ENOMEM otherwise
454 */
smack_bprm_set_creds(struct linux_binprm * bprm)455 static int smack_bprm_set_creds(struct linux_binprm *bprm)
456 {
457 struct inode *inode = bprm->file->f_path.dentry->d_inode;
458 struct task_smack *bsp = bprm->cred->security;
459 struct inode_smack *isp;
460 int rc;
461
462 rc = cap_bprm_set_creds(bprm);
463 if (rc != 0)
464 return rc;
465
466 if (bprm->cred_prepared)
467 return 0;
468
469 isp = inode->i_security;
470 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
471 return 0;
472
473 if (bprm->unsafe)
474 return -EPERM;
475
476 bsp->smk_task = isp->smk_task;
477 bprm->per_clear |= PER_CLEAR_ON_SETID;
478
479 return 0;
480 }
481
482 /**
483 * smack_bprm_committing_creds - Prepare to install the new credentials
484 * from bprm.
485 *
486 * @bprm: binprm for exec
487 */
smack_bprm_committing_creds(struct linux_binprm * bprm)488 static void smack_bprm_committing_creds(struct linux_binprm *bprm)
489 {
490 struct task_smack *bsp = bprm->cred->security;
491
492 if (bsp->smk_task != bsp->smk_forked)
493 current->pdeath_signal = 0;
494 }
495
496 /**
497 * smack_bprm_secureexec - Return the decision to use secureexec.
498 * @bprm: binprm for exec
499 *
500 * Returns 0 on success.
501 */
smack_bprm_secureexec(struct linux_binprm * bprm)502 static int smack_bprm_secureexec(struct linux_binprm *bprm)
503 {
504 struct task_smack *tsp = current_security();
505 int ret = cap_bprm_secureexec(bprm);
506
507 if (!ret && (tsp->smk_task != tsp->smk_forked))
508 ret = 1;
509
510 return ret;
511 }
512
513 /*
514 * Inode hooks
515 */
516
517 /**
518 * smack_inode_alloc_security - allocate an inode blob
519 * @inode: the inode in need of a blob
520 *
521 * Returns 0 if it gets a blob, -ENOMEM otherwise
522 */
smack_inode_alloc_security(struct inode * inode)523 static int smack_inode_alloc_security(struct inode *inode)
524 {
525 inode->i_security = new_inode_smack(smk_of_current());
526 if (inode->i_security == NULL)
527 return -ENOMEM;
528 return 0;
529 }
530
531 /**
532 * smack_inode_free_security - free an inode blob
533 * @inode: the inode with a blob
534 *
535 * Clears the blob pointer in inode
536 */
smack_inode_free_security(struct inode * inode)537 static void smack_inode_free_security(struct inode *inode)
538 {
539 kfree(inode->i_security);
540 inode->i_security = NULL;
541 }
542
543 /**
544 * smack_inode_init_security - copy out the smack from an inode
545 * @inode: the inode
546 * @dir: unused
547 * @qstr: unused
548 * @name: where to put the attribute name
549 * @value: where to put the attribute value
550 * @len: where to put the length of the attribute
551 *
552 * Returns 0 if it all works out, -ENOMEM if there's no memory
553 */
smack_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,char ** name,void ** value,size_t * len)554 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
555 const struct qstr *qstr, char **name,
556 void **value, size_t *len)
557 {
558 struct smack_known *skp;
559 char *csp = smk_of_current();
560 char *isp = smk_of_inode(inode);
561 char *dsp = smk_of_inode(dir);
562 int may;
563
564 if (name) {
565 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
566 if (*name == NULL)
567 return -ENOMEM;
568 }
569
570 if (value) {
571 skp = smk_find_entry(csp);
572 rcu_read_lock();
573 may = smk_access_entry(csp, dsp, &skp->smk_rules);
574 rcu_read_unlock();
575
576 /*
577 * If the access rule allows transmutation and
578 * the directory requests transmutation then
579 * by all means transmute.
580 */
581 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
582 smk_inode_transmutable(dir))
583 isp = dsp;
584
585 *value = kstrdup(isp, GFP_KERNEL);
586 if (*value == NULL)
587 return -ENOMEM;
588 }
589
590 if (len)
591 *len = strlen(isp) + 1;
592
593 return 0;
594 }
595
596 /**
597 * smack_inode_link - Smack check on link
598 * @old_dentry: the existing object
599 * @dir: unused
600 * @new_dentry: the new object
601 *
602 * Returns 0 if access is permitted, an error code otherwise
603 */
smack_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)604 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
605 struct dentry *new_dentry)
606 {
607 char *isp;
608 struct smk_audit_info ad;
609 int rc;
610
611 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
612 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
613
614 isp = smk_of_inode(old_dentry->d_inode);
615 rc = smk_curacc(isp, MAY_WRITE, &ad);
616
617 if (rc == 0 && new_dentry->d_inode != NULL) {
618 isp = smk_of_inode(new_dentry->d_inode);
619 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
620 rc = smk_curacc(isp, MAY_WRITE, &ad);
621 }
622
623 return rc;
624 }
625
626 /**
627 * smack_inode_unlink - Smack check on inode deletion
628 * @dir: containing directory object
629 * @dentry: file to unlink
630 *
631 * Returns 0 if current can write the containing directory
632 * and the object, error code otherwise
633 */
smack_inode_unlink(struct inode * dir,struct dentry * dentry)634 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
635 {
636 struct inode *ip = dentry->d_inode;
637 struct smk_audit_info ad;
638 int rc;
639
640 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
641 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
642
643 /*
644 * You need write access to the thing you're unlinking
645 */
646 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
647 if (rc == 0) {
648 /*
649 * You also need write access to the containing directory
650 */
651 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
652 smk_ad_setfield_u_fs_inode(&ad, dir);
653 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
654 }
655 return rc;
656 }
657
658 /**
659 * smack_inode_rmdir - Smack check on directory deletion
660 * @dir: containing directory object
661 * @dentry: directory to unlink
662 *
663 * Returns 0 if current can write the containing directory
664 * and the directory, error code otherwise
665 */
smack_inode_rmdir(struct inode * dir,struct dentry * dentry)666 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
667 {
668 struct smk_audit_info ad;
669 int rc;
670
671 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
672 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
673
674 /*
675 * You need write access to the thing you're removing
676 */
677 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
678 if (rc == 0) {
679 /*
680 * You also need write access to the containing directory
681 */
682 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
683 smk_ad_setfield_u_fs_inode(&ad, dir);
684 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
685 }
686
687 return rc;
688 }
689
690 /**
691 * smack_inode_rename - Smack check on rename
692 * @old_inode: the old directory
693 * @old_dentry: unused
694 * @new_inode: the new directory
695 * @new_dentry: unused
696 *
697 * Read and write access is required on both the old and
698 * new directories.
699 *
700 * Returns 0 if access is permitted, an error code otherwise
701 */
smack_inode_rename(struct inode * old_inode,struct dentry * old_dentry,struct inode * new_inode,struct dentry * new_dentry)702 static int smack_inode_rename(struct inode *old_inode,
703 struct dentry *old_dentry,
704 struct inode *new_inode,
705 struct dentry *new_dentry)
706 {
707 int rc;
708 char *isp;
709 struct smk_audit_info ad;
710
711 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
712 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
713
714 isp = smk_of_inode(old_dentry->d_inode);
715 rc = smk_curacc(isp, MAY_READWRITE, &ad);
716
717 if (rc == 0 && new_dentry->d_inode != NULL) {
718 isp = smk_of_inode(new_dentry->d_inode);
719 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
720 rc = smk_curacc(isp, MAY_READWRITE, &ad);
721 }
722 return rc;
723 }
724
725 /**
726 * smack_inode_permission - Smack version of permission()
727 * @inode: the inode in question
728 * @mask: the access requested
729 *
730 * This is the important Smack hook.
731 *
732 * Returns 0 if access is permitted, -EACCES otherwise
733 */
smack_inode_permission(struct inode * inode,int mask)734 static int smack_inode_permission(struct inode *inode, int mask)
735 {
736 struct smk_audit_info ad;
737 int no_block = mask & MAY_NOT_BLOCK;
738
739 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
740 /*
741 * No permission to check. Existence test. Yup, it's there.
742 */
743 if (mask == 0)
744 return 0;
745
746 /* May be droppable after audit */
747 if (no_block)
748 return -ECHILD;
749 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
750 smk_ad_setfield_u_fs_inode(&ad, inode);
751 return smk_curacc(smk_of_inode(inode), mask, &ad);
752 }
753
754 /**
755 * smack_inode_setattr - Smack check for setting attributes
756 * @dentry: the object
757 * @iattr: for the force flag
758 *
759 * Returns 0 if access is permitted, an error code otherwise
760 */
smack_inode_setattr(struct dentry * dentry,struct iattr * iattr)761 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
762 {
763 struct smk_audit_info ad;
764 /*
765 * Need to allow for clearing the setuid bit.
766 */
767 if (iattr->ia_valid & ATTR_FORCE)
768 return 0;
769 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
770 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
771
772 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
773 }
774
775 /**
776 * smack_inode_getattr - Smack check for getting attributes
777 * @mnt: unused
778 * @dentry: the object
779 *
780 * Returns 0 if access is permitted, an error code otherwise
781 */
smack_inode_getattr(struct vfsmount * mnt,struct dentry * dentry)782 static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
783 {
784 struct smk_audit_info ad;
785 struct path path;
786
787 path.dentry = dentry;
788 path.mnt = mnt;
789
790 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
791 smk_ad_setfield_u_fs_path(&ad, path);
792 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
793 }
794
795 /**
796 * smack_inode_setxattr - Smack check for setting xattrs
797 * @dentry: the object
798 * @name: name of the attribute
799 * @value: unused
800 * @size: unused
801 * @flags: unused
802 *
803 * This protects the Smack attribute explicitly.
804 *
805 * Returns 0 if access is permitted, an error code otherwise
806 */
smack_inode_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)807 static int smack_inode_setxattr(struct dentry *dentry, const char *name,
808 const void *value, size_t size, int flags)
809 {
810 struct smk_audit_info ad;
811 int rc = 0;
812
813 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
814 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
815 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
816 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
817 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
818 if (!capable(CAP_MAC_ADMIN))
819 rc = -EPERM;
820 /*
821 * check label validity here so import wont fail on
822 * post_setxattr
823 */
824 if (size == 0 || size >= SMK_LABELLEN ||
825 smk_import(value, size) == NULL)
826 rc = -EINVAL;
827 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
828 if (!capable(CAP_MAC_ADMIN))
829 rc = -EPERM;
830 if (size != TRANS_TRUE_SIZE ||
831 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
832 rc = -EINVAL;
833 } else
834 rc = cap_inode_setxattr(dentry, name, value, size, flags);
835
836 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
837 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
838
839 if (rc == 0)
840 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
841
842 return rc;
843 }
844
845 /**
846 * smack_inode_post_setxattr - Apply the Smack update approved above
847 * @dentry: object
848 * @name: attribute name
849 * @value: attribute value
850 * @size: attribute size
851 * @flags: unused
852 *
853 * Set the pointer in the inode blob to the entry found
854 * in the master label list.
855 */
smack_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)856 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
857 const void *value, size_t size, int flags)
858 {
859 char *nsp;
860 struct inode_smack *isp = dentry->d_inode->i_security;
861
862 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
863 nsp = smk_import(value, size);
864 if (nsp != NULL)
865 isp->smk_inode = nsp;
866 else
867 isp->smk_inode = smack_known_invalid.smk_known;
868 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
869 nsp = smk_import(value, size);
870 if (nsp != NULL)
871 isp->smk_task = nsp;
872 else
873 isp->smk_task = smack_known_invalid.smk_known;
874 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
875 nsp = smk_import(value, size);
876 if (nsp != NULL)
877 isp->smk_mmap = nsp;
878 else
879 isp->smk_mmap = smack_known_invalid.smk_known;
880 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
881 isp->smk_flags |= SMK_INODE_TRANSMUTE;
882
883 return;
884 }
885
886 /**
887 * smack_inode_getxattr - Smack check on getxattr
888 * @dentry: the object
889 * @name: unused
890 *
891 * Returns 0 if access is permitted, an error code otherwise
892 */
smack_inode_getxattr(struct dentry * dentry,const char * name)893 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
894 {
895 struct smk_audit_info ad;
896
897 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
898 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
899
900 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
901 }
902
903 /**
904 * smack_inode_removexattr - Smack check on removexattr
905 * @dentry: the object
906 * @name: name of the attribute
907 *
908 * Removing the Smack attribute requires CAP_MAC_ADMIN
909 *
910 * Returns 0 if access is permitted, an error code otherwise
911 */
smack_inode_removexattr(struct dentry * dentry,const char * name)912 static int smack_inode_removexattr(struct dentry *dentry, const char *name)
913 {
914 struct inode_smack *isp;
915 struct smk_audit_info ad;
916 int rc = 0;
917
918 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
919 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
920 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
921 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
922 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
923 strcmp(name, XATTR_NAME_SMACKMMAP)) {
924 if (!capable(CAP_MAC_ADMIN))
925 rc = -EPERM;
926 } else
927 rc = cap_inode_removexattr(dentry, name);
928
929 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
930 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
931 if (rc == 0)
932 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
933
934 if (rc == 0) {
935 isp = dentry->d_inode->i_security;
936 isp->smk_task = NULL;
937 isp->smk_mmap = NULL;
938 }
939
940 return rc;
941 }
942
943 /**
944 * smack_inode_getsecurity - get smack xattrs
945 * @inode: the object
946 * @name: attribute name
947 * @buffer: where to put the result
948 * @alloc: unused
949 *
950 * Returns the size of the attribute or an error code
951 */
smack_inode_getsecurity(const struct inode * inode,const char * name,void ** buffer,bool alloc)952 static int smack_inode_getsecurity(const struct inode *inode,
953 const char *name, void **buffer,
954 bool alloc)
955 {
956 struct socket_smack *ssp;
957 struct socket *sock;
958 struct super_block *sbp;
959 struct inode *ip = (struct inode *)inode;
960 char *isp;
961 int ilen;
962 int rc = 0;
963
964 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
965 isp = smk_of_inode(inode);
966 ilen = strlen(isp) + 1;
967 *buffer = isp;
968 return ilen;
969 }
970
971 /*
972 * The rest of the Smack xattrs are only on sockets.
973 */
974 sbp = ip->i_sb;
975 if (sbp->s_magic != SOCKFS_MAGIC)
976 return -EOPNOTSUPP;
977
978 sock = SOCKET_I(ip);
979 if (sock == NULL || sock->sk == NULL)
980 return -EOPNOTSUPP;
981
982 ssp = sock->sk->sk_security;
983
984 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
985 isp = ssp->smk_in;
986 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
987 isp = ssp->smk_out;
988 else
989 return -EOPNOTSUPP;
990
991 ilen = strlen(isp) + 1;
992 if (rc == 0) {
993 *buffer = isp;
994 rc = ilen;
995 }
996
997 return rc;
998 }
999
1000
1001 /**
1002 * smack_inode_listsecurity - list the Smack attributes
1003 * @inode: the object
1004 * @buffer: where they go
1005 * @buffer_size: size of buffer
1006 *
1007 * Returns 0 on success, -EINVAL otherwise
1008 */
smack_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)1009 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1010 size_t buffer_size)
1011 {
1012 int len = strlen(XATTR_NAME_SMACK);
1013
1014 if (buffer != NULL && len <= buffer_size) {
1015 memcpy(buffer, XATTR_NAME_SMACK, len);
1016 return len;
1017 }
1018 return -EINVAL;
1019 }
1020
1021 /**
1022 * smack_inode_getsecid - Extract inode's security id
1023 * @inode: inode to extract the info from
1024 * @secid: where result will be saved
1025 */
smack_inode_getsecid(const struct inode * inode,u32 * secid)1026 static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
1027 {
1028 struct inode_smack *isp = inode->i_security;
1029
1030 *secid = smack_to_secid(isp->smk_inode);
1031 }
1032
1033 /*
1034 * File Hooks
1035 */
1036
1037 /**
1038 * smack_file_permission - Smack check on file operations
1039 * @file: unused
1040 * @mask: unused
1041 *
1042 * Returns 0
1043 *
1044 * Should access checks be done on each read or write?
1045 * UNICOS and SELinux say yes.
1046 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1047 *
1048 * I'll say no for now. Smack does not do the frequent
1049 * label changing that SELinux does.
1050 */
smack_file_permission(struct file * file,int mask)1051 static int smack_file_permission(struct file *file, int mask)
1052 {
1053 return 0;
1054 }
1055
1056 /**
1057 * smack_file_alloc_security - assign a file security blob
1058 * @file: the object
1059 *
1060 * The security blob for a file is a pointer to the master
1061 * label list, so no allocation is done.
1062 *
1063 * Returns 0
1064 */
smack_file_alloc_security(struct file * file)1065 static int smack_file_alloc_security(struct file *file)
1066 {
1067 file->f_security = smk_of_current();
1068 return 0;
1069 }
1070
1071 /**
1072 * smack_file_free_security - clear a file security blob
1073 * @file: the object
1074 *
1075 * The security blob for a file is a pointer to the master
1076 * label list, so no memory is freed.
1077 */
smack_file_free_security(struct file * file)1078 static void smack_file_free_security(struct file *file)
1079 {
1080 file->f_security = NULL;
1081 }
1082
1083 /**
1084 * smack_file_ioctl - Smack check on ioctls
1085 * @file: the object
1086 * @cmd: what to do
1087 * @arg: unused
1088 *
1089 * Relies heavily on the correct use of the ioctl command conventions.
1090 *
1091 * Returns 0 if allowed, error code otherwise
1092 */
smack_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)1093 static int smack_file_ioctl(struct file *file, unsigned int cmd,
1094 unsigned long arg)
1095 {
1096 int rc = 0;
1097 struct smk_audit_info ad;
1098
1099 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1100 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1101
1102 if (_IOC_DIR(cmd) & _IOC_WRITE)
1103 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1104
1105 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
1106 rc = smk_curacc(file->f_security, MAY_READ, &ad);
1107
1108 return rc;
1109 }
1110
1111 /**
1112 * smack_file_lock - Smack check on file locking
1113 * @file: the object
1114 * @cmd: unused
1115 *
1116 * Returns 0 if current has write access, error code otherwise
1117 */
smack_file_lock(struct file * file,unsigned int cmd)1118 static int smack_file_lock(struct file *file, unsigned int cmd)
1119 {
1120 struct smk_audit_info ad;
1121
1122 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1123 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1124 return smk_curacc(file->f_security, MAY_WRITE, &ad);
1125 }
1126
1127 /**
1128 * smack_file_fcntl - Smack check on fcntl
1129 * @file: the object
1130 * @cmd: what action to check
1131 * @arg: unused
1132 *
1133 * Generally these operations are harmless.
1134 * File locking operations present an obvious mechanism
1135 * for passing information, so they require write access.
1136 *
1137 * Returns 0 if current has access, error code otherwise
1138 */
smack_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)1139 static int smack_file_fcntl(struct file *file, unsigned int cmd,
1140 unsigned long arg)
1141 {
1142 struct smk_audit_info ad;
1143 int rc = 0;
1144
1145
1146 switch (cmd) {
1147 case F_GETLK:
1148 case F_SETLK:
1149 case F_SETLKW:
1150 case F_SETOWN:
1151 case F_SETSIG:
1152 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1153 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1154 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1155 break;
1156 default:
1157 break;
1158 }
1159
1160 return rc;
1161 }
1162
1163 /**
1164 * smack_file_mmap :
1165 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1166 * if mapping anonymous memory.
1167 * @file contains the file structure for file to map (may be NULL).
1168 * @reqprot contains the protection requested by the application.
1169 * @prot contains the protection that will be applied by the kernel.
1170 * @flags contains the operational flags.
1171 * Return 0 if permission is granted.
1172 */
smack_file_mmap(struct file * file,unsigned long reqprot,unsigned long prot,unsigned long flags,unsigned long addr,unsigned long addr_only)1173 static int smack_file_mmap(struct file *file,
1174 unsigned long reqprot, unsigned long prot,
1175 unsigned long flags, unsigned long addr,
1176 unsigned long addr_only)
1177 {
1178 struct smack_known *skp;
1179 struct smack_rule *srp;
1180 struct task_smack *tsp;
1181 char *sp;
1182 char *msmack;
1183 char *osmack;
1184 struct inode_smack *isp;
1185 struct dentry *dp;
1186 int may;
1187 int mmay;
1188 int tmay;
1189 int rc;
1190
1191 /* do DAC check on address space usage */
1192 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
1193 if (rc || addr_only)
1194 return rc;
1195
1196 if (file == NULL || file->f_dentry == NULL)
1197 return 0;
1198
1199 dp = file->f_dentry;
1200
1201 if (dp->d_inode == NULL)
1202 return 0;
1203
1204 isp = dp->d_inode->i_security;
1205 if (isp->smk_mmap == NULL)
1206 return 0;
1207 msmack = isp->smk_mmap;
1208
1209 tsp = current_security();
1210 sp = smk_of_current();
1211 skp = smk_find_entry(sp);
1212 rc = 0;
1213
1214 rcu_read_lock();
1215 /*
1216 * For each Smack rule associated with the subject
1217 * label verify that the SMACK64MMAP also has access
1218 * to that rule's object label.
1219 */
1220 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1221 osmack = srp->smk_object;
1222 /*
1223 * Matching labels always allows access.
1224 */
1225 if (msmack == osmack)
1226 continue;
1227 /*
1228 * If there is a matching local rule take
1229 * that into account as well.
1230 */
1231 may = smk_access_entry(srp->smk_subject, osmack,
1232 &tsp->smk_rules);
1233 if (may == -ENOENT)
1234 may = srp->smk_access;
1235 else
1236 may &= srp->smk_access;
1237 /*
1238 * If may is zero the SMACK64MMAP subject can't
1239 * possibly have less access.
1240 */
1241 if (may == 0)
1242 continue;
1243
1244 /*
1245 * Fetch the global list entry.
1246 * If there isn't one a SMACK64MMAP subject
1247 * can't have as much access as current.
1248 */
1249 skp = smk_find_entry(msmack);
1250 mmay = smk_access_entry(msmack, osmack, &skp->smk_rules);
1251 if (mmay == -ENOENT) {
1252 rc = -EACCES;
1253 break;
1254 }
1255 /*
1256 * If there is a local entry it modifies the
1257 * potential access, too.
1258 */
1259 tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules);
1260 if (tmay != -ENOENT)
1261 mmay &= tmay;
1262
1263 /*
1264 * If there is any access available to current that is
1265 * not available to a SMACK64MMAP subject
1266 * deny access.
1267 */
1268 if ((may | mmay) != mmay) {
1269 rc = -EACCES;
1270 break;
1271 }
1272 }
1273
1274 rcu_read_unlock();
1275
1276 return rc;
1277 }
1278
1279 /**
1280 * smack_file_set_fowner - set the file security blob value
1281 * @file: object in question
1282 *
1283 * Returns 0
1284 * Further research may be required on this one.
1285 */
smack_file_set_fowner(struct file * file)1286 static int smack_file_set_fowner(struct file *file)
1287 {
1288 file->f_security = smk_of_current();
1289 return 0;
1290 }
1291
1292 /**
1293 * smack_file_send_sigiotask - Smack on sigio
1294 * @tsk: The target task
1295 * @fown: the object the signal come from
1296 * @signum: unused
1297 *
1298 * Allow a privileged task to get signals even if it shouldn't
1299 *
1300 * Returns 0 if a subject with the object's smack could
1301 * write to the task, an error code otherwise.
1302 */
smack_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int signum)1303 static int smack_file_send_sigiotask(struct task_struct *tsk,
1304 struct fown_struct *fown, int signum)
1305 {
1306 struct file *file;
1307 int rc;
1308 char *tsp = smk_of_task(tsk->cred->security);
1309 struct smk_audit_info ad;
1310
1311 /*
1312 * struct fown_struct is never outside the context of a struct file
1313 */
1314 file = container_of(fown, struct file, f_owner);
1315
1316 /* we don't log here as rc can be overriden */
1317 rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
1318 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1319 rc = 0;
1320
1321 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1322 smk_ad_setfield_u_tsk(&ad, tsk);
1323 smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
1324 return rc;
1325 }
1326
1327 /**
1328 * smack_file_receive - Smack file receive check
1329 * @file: the object
1330 *
1331 * Returns 0 if current has access, error code otherwise
1332 */
smack_file_receive(struct file * file)1333 static int smack_file_receive(struct file *file)
1334 {
1335 int may = 0;
1336 struct smk_audit_info ad;
1337
1338 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1339 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1340 /*
1341 * This code relies on bitmasks.
1342 */
1343 if (file->f_mode & FMODE_READ)
1344 may = MAY_READ;
1345 if (file->f_mode & FMODE_WRITE)
1346 may |= MAY_WRITE;
1347
1348 return smk_curacc(file->f_security, may, &ad);
1349 }
1350
1351 /**
1352 * smack_dentry_open - Smack dentry open processing
1353 * @file: the object
1354 * @cred: unused
1355 *
1356 * Set the security blob in the file structure.
1357 *
1358 * Returns 0
1359 */
smack_dentry_open(struct file * file,const struct cred * cred)1360 static int smack_dentry_open(struct file *file, const struct cred *cred)
1361 {
1362 struct inode_smack *isp = file->f_path.dentry->d_inode->i_security;
1363
1364 file->f_security = isp->smk_inode;
1365
1366 return 0;
1367 }
1368
1369 /*
1370 * Task hooks
1371 */
1372
1373 /**
1374 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1375 * @new: the new credentials
1376 * @gfp: the atomicity of any memory allocations
1377 *
1378 * Prepare a blank set of credentials for modification. This must allocate all
1379 * the memory the LSM module might require such that cred_transfer() can
1380 * complete without error.
1381 */
smack_cred_alloc_blank(struct cred * cred,gfp_t gfp)1382 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1383 {
1384 struct task_smack *tsp;
1385
1386 tsp = new_task_smack(NULL, NULL, gfp);
1387 if (tsp == NULL)
1388 return -ENOMEM;
1389
1390 cred->security = tsp;
1391
1392 return 0;
1393 }
1394
1395
1396 /**
1397 * smack_cred_free - "free" task-level security credentials
1398 * @cred: the credentials in question
1399 *
1400 */
smack_cred_free(struct cred * cred)1401 static void smack_cred_free(struct cred *cred)
1402 {
1403 struct task_smack *tsp = cred->security;
1404 struct smack_rule *rp;
1405 struct list_head *l;
1406 struct list_head *n;
1407
1408 if (tsp == NULL)
1409 return;
1410 cred->security = NULL;
1411
1412 list_for_each_safe(l, n, &tsp->smk_rules) {
1413 rp = list_entry(l, struct smack_rule, list);
1414 list_del(&rp->list);
1415 kfree(rp);
1416 }
1417 kfree(tsp);
1418 }
1419
1420 /**
1421 * smack_cred_prepare - prepare new set of credentials for modification
1422 * @new: the new credentials
1423 * @old: the original credentials
1424 * @gfp: the atomicity of any memory allocations
1425 *
1426 * Prepare a new set of credentials for modification.
1427 */
smack_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)1428 static int smack_cred_prepare(struct cred *new, const struct cred *old,
1429 gfp_t gfp)
1430 {
1431 struct task_smack *old_tsp = old->security;
1432 struct task_smack *new_tsp;
1433 int rc;
1434
1435 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1436 if (new_tsp == NULL)
1437 return -ENOMEM;
1438
1439 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
1440 if (rc != 0)
1441 return rc;
1442
1443 new->security = new_tsp;
1444 return 0;
1445 }
1446
1447 /**
1448 * smack_cred_transfer - Transfer the old credentials to the new credentials
1449 * @new: the new credentials
1450 * @old: the original credentials
1451 *
1452 * Fill in a set of blank credentials from another set of credentials.
1453 */
smack_cred_transfer(struct cred * new,const struct cred * old)1454 static void smack_cred_transfer(struct cred *new, const struct cred *old)
1455 {
1456 struct task_smack *old_tsp = old->security;
1457 struct task_smack *new_tsp = new->security;
1458
1459 new_tsp->smk_task = old_tsp->smk_task;
1460 new_tsp->smk_forked = old_tsp->smk_task;
1461 mutex_init(&new_tsp->smk_rules_lock);
1462 INIT_LIST_HEAD(&new_tsp->smk_rules);
1463
1464
1465 /* cbs copy rule list */
1466 }
1467
1468 /**
1469 * smack_kernel_act_as - Set the subjective context in a set of credentials
1470 * @new: points to the set of credentials to be modified.
1471 * @secid: specifies the security ID to be set
1472 *
1473 * Set the security data for a kernel service.
1474 */
smack_kernel_act_as(struct cred * new,u32 secid)1475 static int smack_kernel_act_as(struct cred *new, u32 secid)
1476 {
1477 struct task_smack *new_tsp = new->security;
1478 char *smack = smack_from_secid(secid);
1479
1480 if (smack == NULL)
1481 return -EINVAL;
1482
1483 new_tsp->smk_task = smack;
1484 return 0;
1485 }
1486
1487 /**
1488 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1489 * @new: points to the set of credentials to be modified
1490 * @inode: points to the inode to use as a reference
1491 *
1492 * Set the file creation context in a set of credentials to the same
1493 * as the objective context of the specified inode
1494 */
smack_kernel_create_files_as(struct cred * new,struct inode * inode)1495 static int smack_kernel_create_files_as(struct cred *new,
1496 struct inode *inode)
1497 {
1498 struct inode_smack *isp = inode->i_security;
1499 struct task_smack *tsp = new->security;
1500
1501 tsp->smk_forked = isp->smk_inode;
1502 tsp->smk_task = isp->smk_inode;
1503 return 0;
1504 }
1505
1506 /**
1507 * smk_curacc_on_task - helper to log task related access
1508 * @p: the task object
1509 * @access: the access requested
1510 * @caller: name of the calling function for audit
1511 *
1512 * Return 0 if access is permitted
1513 */
smk_curacc_on_task(struct task_struct * p,int access,const char * caller)1514 static int smk_curacc_on_task(struct task_struct *p, int access,
1515 const char *caller)
1516 {
1517 struct smk_audit_info ad;
1518
1519 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
1520 smk_ad_setfield_u_tsk(&ad, p);
1521 return smk_curacc(smk_of_task(task_security(p)), access, &ad);
1522 }
1523
1524 /**
1525 * smack_task_setpgid - Smack check on setting pgid
1526 * @p: the task object
1527 * @pgid: unused
1528 *
1529 * Return 0 if write access is permitted
1530 */
smack_task_setpgid(struct task_struct * p,pid_t pgid)1531 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1532 {
1533 return smk_curacc_on_task(p, MAY_WRITE, __func__);
1534 }
1535
1536 /**
1537 * smack_task_getpgid - Smack access check for getpgid
1538 * @p: the object task
1539 *
1540 * Returns 0 if current can read the object task, error code otherwise
1541 */
smack_task_getpgid(struct task_struct * p)1542 static int smack_task_getpgid(struct task_struct *p)
1543 {
1544 return smk_curacc_on_task(p, MAY_READ, __func__);
1545 }
1546
1547 /**
1548 * smack_task_getsid - Smack access check for getsid
1549 * @p: the object task
1550 *
1551 * Returns 0 if current can read the object task, error code otherwise
1552 */
smack_task_getsid(struct task_struct * p)1553 static int smack_task_getsid(struct task_struct *p)
1554 {
1555 return smk_curacc_on_task(p, MAY_READ, __func__);
1556 }
1557
1558 /**
1559 * smack_task_getsecid - get the secid of the task
1560 * @p: the object task
1561 * @secid: where to put the result
1562 *
1563 * Sets the secid to contain a u32 version of the smack label.
1564 */
smack_task_getsecid(struct task_struct * p,u32 * secid)1565 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1566 {
1567 *secid = smack_to_secid(smk_of_task(task_security(p)));
1568 }
1569
1570 /**
1571 * smack_task_setnice - Smack check on setting nice
1572 * @p: the task object
1573 * @nice: unused
1574 *
1575 * Return 0 if write access is permitted
1576 */
smack_task_setnice(struct task_struct * p,int nice)1577 static int smack_task_setnice(struct task_struct *p, int nice)
1578 {
1579 int rc;
1580
1581 rc = cap_task_setnice(p, nice);
1582 if (rc == 0)
1583 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1584 return rc;
1585 }
1586
1587 /**
1588 * smack_task_setioprio - Smack check on setting ioprio
1589 * @p: the task object
1590 * @ioprio: unused
1591 *
1592 * Return 0 if write access is permitted
1593 */
smack_task_setioprio(struct task_struct * p,int ioprio)1594 static int smack_task_setioprio(struct task_struct *p, int ioprio)
1595 {
1596 int rc;
1597
1598 rc = cap_task_setioprio(p, ioprio);
1599 if (rc == 0)
1600 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1601 return rc;
1602 }
1603
1604 /**
1605 * smack_task_getioprio - Smack check on reading ioprio
1606 * @p: the task object
1607 *
1608 * Return 0 if read access is permitted
1609 */
smack_task_getioprio(struct task_struct * p)1610 static int smack_task_getioprio(struct task_struct *p)
1611 {
1612 return smk_curacc_on_task(p, MAY_READ, __func__);
1613 }
1614
1615 /**
1616 * smack_task_setscheduler - Smack check on setting scheduler
1617 * @p: the task object
1618 * @policy: unused
1619 * @lp: unused
1620 *
1621 * Return 0 if read access is permitted
1622 */
smack_task_setscheduler(struct task_struct * p)1623 static int smack_task_setscheduler(struct task_struct *p)
1624 {
1625 int rc;
1626
1627 rc = cap_task_setscheduler(p);
1628 if (rc == 0)
1629 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1630 return rc;
1631 }
1632
1633 /**
1634 * smack_task_getscheduler - Smack check on reading scheduler
1635 * @p: the task object
1636 *
1637 * Return 0 if read access is permitted
1638 */
smack_task_getscheduler(struct task_struct * p)1639 static int smack_task_getscheduler(struct task_struct *p)
1640 {
1641 return smk_curacc_on_task(p, MAY_READ, __func__);
1642 }
1643
1644 /**
1645 * smack_task_movememory - Smack check on moving memory
1646 * @p: the task object
1647 *
1648 * Return 0 if write access is permitted
1649 */
smack_task_movememory(struct task_struct * p)1650 static int smack_task_movememory(struct task_struct *p)
1651 {
1652 return smk_curacc_on_task(p, MAY_WRITE, __func__);
1653 }
1654
1655 /**
1656 * smack_task_kill - Smack check on signal delivery
1657 * @p: the task object
1658 * @info: unused
1659 * @sig: unused
1660 * @secid: identifies the smack to use in lieu of current's
1661 *
1662 * Return 0 if write access is permitted
1663 *
1664 * The secid behavior is an artifact of an SELinux hack
1665 * in the USB code. Someday it may go away.
1666 */
smack_task_kill(struct task_struct * p,struct siginfo * info,int sig,u32 secid)1667 static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1668 int sig, u32 secid)
1669 {
1670 struct smk_audit_info ad;
1671
1672 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1673 smk_ad_setfield_u_tsk(&ad, p);
1674 /*
1675 * Sending a signal requires that the sender
1676 * can write the receiver.
1677 */
1678 if (secid == 0)
1679 return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE,
1680 &ad);
1681 /*
1682 * If the secid isn't 0 we're dealing with some USB IO
1683 * specific behavior. This is not clean. For one thing
1684 * we can't take privilege into account.
1685 */
1686 return smk_access(smack_from_secid(secid),
1687 smk_of_task(task_security(p)), MAY_WRITE, &ad);
1688 }
1689
1690 /**
1691 * smack_task_wait - Smack access check for waiting
1692 * @p: task to wait for
1693 *
1694 * Returns 0 if current can wait for p, error code otherwise
1695 */
smack_task_wait(struct task_struct * p)1696 static int smack_task_wait(struct task_struct *p)
1697 {
1698 struct smk_audit_info ad;
1699 char *sp = smk_of_current();
1700 char *tsp = smk_of_forked(task_security(p));
1701 int rc;
1702
1703 /* we don't log here, we can be overriden */
1704 rc = smk_access(tsp, sp, MAY_WRITE, NULL);
1705 if (rc == 0)
1706 goto out_log;
1707
1708 /*
1709 * Allow the operation to succeed if either task
1710 * has privilege to perform operations that might
1711 * account for the smack labels having gotten to
1712 * be different in the first place.
1713 *
1714 * This breaks the strict subject/object access
1715 * control ideal, taking the object's privilege
1716 * state into account in the decision as well as
1717 * the smack value.
1718 */
1719 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
1720 rc = 0;
1721 /* we log only if we didn't get overriden */
1722 out_log:
1723 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1724 smk_ad_setfield_u_tsk(&ad, p);
1725 smack_log(tsp, sp, MAY_WRITE, rc, &ad);
1726 return rc;
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 */
smack_task_to_inode(struct task_struct * p,struct inode * inode)1736 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1737 {
1738 struct inode_smack *isp = inode->i_security;
1739 isp->smk_inode = smk_of_task(task_security(p));
1740 }
1741
1742 /*
1743 * Socket hooks.
1744 */
1745
1746 /**
1747 * smack_sk_alloc_security - Allocate a socket blob
1748 * @sk: the socket
1749 * @family: unused
1750 * @gfp_flags: memory allocation flags
1751 *
1752 * Assign Smack pointers to current
1753 *
1754 * Returns 0 on success, -ENOMEM is there's no memory
1755 */
smack_sk_alloc_security(struct sock * sk,int family,gfp_t gfp_flags)1756 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1757 {
1758 char *csp = smk_of_current();
1759 struct socket_smack *ssp;
1760
1761 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1762 if (ssp == NULL)
1763 return -ENOMEM;
1764
1765 ssp->smk_in = csp;
1766 ssp->smk_out = csp;
1767 ssp->smk_packet = NULL;
1768
1769 sk->sk_security = ssp;
1770
1771 return 0;
1772 }
1773
1774 /**
1775 * smack_sk_free_security - Free a socket blob
1776 * @sk: the socket
1777 *
1778 * Clears the blob pointer
1779 */
smack_sk_free_security(struct sock * sk)1780 static void smack_sk_free_security(struct sock *sk)
1781 {
1782 kfree(sk->sk_security);
1783 }
1784
1785 /**
1786 * smack_host_label - check host based restrictions
1787 * @sip: the object end
1788 *
1789 * looks for host based access restrictions
1790 *
1791 * This version will only be appropriate for really small sets of single label
1792 * hosts. The caller is responsible for ensuring that the RCU read lock is
1793 * taken before calling this function.
1794 *
1795 * Returns the label of the far end or NULL if it's not special.
1796 */
smack_host_label(struct sockaddr_in * sip)1797 static char *smack_host_label(struct sockaddr_in *sip)
1798 {
1799 struct smk_netlbladdr *snp;
1800 struct in_addr *siap = &sip->sin_addr;
1801
1802 if (siap->s_addr == 0)
1803 return NULL;
1804
1805 list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list)
1806 /*
1807 * we break after finding the first match because
1808 * the list is sorted from longest to shortest mask
1809 * so we have found the most specific match
1810 */
1811 if ((&snp->smk_host.sin_addr)->s_addr ==
1812 (siap->s_addr & (&snp->smk_mask)->s_addr)) {
1813 /* we have found the special CIPSO option */
1814 if (snp->smk_label == smack_cipso_option)
1815 return NULL;
1816 return snp->smk_label;
1817 }
1818
1819 return NULL;
1820 }
1821
1822 /**
1823 * smack_set_catset - convert a capset to netlabel mls categories
1824 * @catset: the Smack categories
1825 * @sap: where to put the netlabel categories
1826 *
1827 * Allocates and fills attr.mls.cat
1828 */
smack_set_catset(char * catset,struct netlbl_lsm_secattr * sap)1829 static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1830 {
1831 unsigned char *cp;
1832 unsigned char m;
1833 int cat;
1834 int rc;
1835 int byte;
1836
1837 if (!catset)
1838 return;
1839
1840 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1841 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1842 sap->attr.mls.cat->startbit = 0;
1843
1844 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1845 for (m = 0x80; m != 0; m >>= 1, cat++) {
1846 if ((m & *cp) == 0)
1847 continue;
1848 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1849 cat, GFP_ATOMIC);
1850 }
1851 }
1852
1853 /**
1854 * smack_to_secattr - fill a secattr from a smack value
1855 * @smack: the smack value
1856 * @nlsp: where the result goes
1857 *
1858 * Casey says that CIPSO is good enough for now.
1859 * It can be used to effect.
1860 * It can also be abused to effect when necessary.
1861 * Apologies to the TSIG group in general and GW in particular.
1862 */
smack_to_secattr(char * smack,struct netlbl_lsm_secattr * nlsp)1863 static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1864 {
1865 struct smack_cipso cipso;
1866 int rc;
1867
1868 nlsp->domain = smack;
1869 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1870
1871 rc = smack_to_cipso(smack, &cipso);
1872 if (rc == 0) {
1873 nlsp->attr.mls.lvl = cipso.smk_level;
1874 smack_set_catset(cipso.smk_catset, nlsp);
1875 } else {
1876 nlsp->attr.mls.lvl = smack_cipso_direct;
1877 smack_set_catset(smack, nlsp);
1878 }
1879 }
1880
1881 /**
1882 * smack_netlabel - Set the secattr on a socket
1883 * @sk: the socket
1884 * @labeled: socket label scheme
1885 *
1886 * Convert the outbound smack value (smk_out) to a
1887 * secattr and attach it to the socket.
1888 *
1889 * Returns 0 on success or an error code
1890 */
smack_netlabel(struct sock * sk,int labeled)1891 static int smack_netlabel(struct sock *sk, int labeled)
1892 {
1893 struct socket_smack *ssp = sk->sk_security;
1894 struct netlbl_lsm_secattr secattr;
1895 int rc = 0;
1896
1897 /*
1898 * Usually the netlabel code will handle changing the
1899 * packet labeling based on the label.
1900 * The case of a single label host is different, because
1901 * a single label host should never get a labeled packet
1902 * even though the label is usually associated with a packet
1903 * label.
1904 */
1905 local_bh_disable();
1906 bh_lock_sock_nested(sk);
1907
1908 if (ssp->smk_out == smack_net_ambient ||
1909 labeled == SMACK_UNLABELED_SOCKET)
1910 netlbl_sock_delattr(sk);
1911 else {
1912 netlbl_secattr_init(&secattr);
1913 smack_to_secattr(ssp->smk_out, &secattr);
1914 rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
1915 netlbl_secattr_destroy(&secattr);
1916 }
1917
1918 bh_unlock_sock(sk);
1919 local_bh_enable();
1920
1921 return rc;
1922 }
1923
1924 /**
1925 * smack_netlbel_send - Set the secattr on a socket and perform access checks
1926 * @sk: the socket
1927 * @sap: the destination address
1928 *
1929 * Set the correct secattr for the given socket based on the destination
1930 * address and perform any outbound access checks needed.
1931 *
1932 * Returns 0 on success or an error code.
1933 *
1934 */
smack_netlabel_send(struct sock * sk,struct sockaddr_in * sap)1935 static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
1936 {
1937 int rc;
1938 int sk_lbl;
1939 char *hostsp;
1940 struct socket_smack *ssp = sk->sk_security;
1941 struct smk_audit_info ad;
1942
1943 rcu_read_lock();
1944 hostsp = smack_host_label(sap);
1945 if (hostsp != NULL) {
1946 #ifdef CONFIG_AUDIT
1947 struct lsm_network_audit net;
1948
1949 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
1950 ad.a.u.net->family = sap->sin_family;
1951 ad.a.u.net->dport = sap->sin_port;
1952 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
1953 #endif
1954 sk_lbl = SMACK_UNLABELED_SOCKET;
1955 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
1956 } else {
1957 sk_lbl = SMACK_CIPSO_SOCKET;
1958 rc = 0;
1959 }
1960 rcu_read_unlock();
1961 if (rc != 0)
1962 return rc;
1963
1964 return smack_netlabel(sk, sk_lbl);
1965 }
1966
1967 /**
1968 * smack_inode_setsecurity - set smack xattrs
1969 * @inode: the object
1970 * @name: attribute name
1971 * @value: attribute value
1972 * @size: size of the attribute
1973 * @flags: unused
1974 *
1975 * Sets the named attribute in the appropriate blob
1976 *
1977 * Returns 0 on success, or an error code
1978 */
smack_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)1979 static int smack_inode_setsecurity(struct inode *inode, const char *name,
1980 const void *value, size_t size, int flags)
1981 {
1982 char *sp;
1983 struct inode_smack *nsp = inode->i_security;
1984 struct socket_smack *ssp;
1985 struct socket *sock;
1986 int rc = 0;
1987
1988 if (value == NULL || size > SMK_LABELLEN || size == 0)
1989 return -EACCES;
1990
1991 sp = smk_import(value, size);
1992 if (sp == NULL)
1993 return -EINVAL;
1994
1995 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1996 nsp->smk_inode = sp;
1997 nsp->smk_flags |= SMK_INODE_INSTANT;
1998 return 0;
1999 }
2000 /*
2001 * The rest of the Smack xattrs are only on sockets.
2002 */
2003 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2004 return -EOPNOTSUPP;
2005
2006 sock = SOCKET_I(inode);
2007 if (sock == NULL || sock->sk == NULL)
2008 return -EOPNOTSUPP;
2009
2010 ssp = sock->sk->sk_security;
2011
2012 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2013 ssp->smk_in = sp;
2014 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2015 ssp->smk_out = sp;
2016 if (sock->sk->sk_family != PF_UNIX) {
2017 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2018 if (rc != 0)
2019 printk(KERN_WARNING
2020 "Smack: \"%s\" netlbl error %d.\n",
2021 __func__, -rc);
2022 }
2023 } else
2024 return -EOPNOTSUPP;
2025
2026 return 0;
2027 }
2028
2029 /**
2030 * smack_socket_post_create - finish socket setup
2031 * @sock: the socket
2032 * @family: protocol family
2033 * @type: unused
2034 * @protocol: unused
2035 * @kern: unused
2036 *
2037 * Sets the netlabel information on the socket
2038 *
2039 * Returns 0 on success, and error code otherwise
2040 */
smack_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)2041 static int smack_socket_post_create(struct socket *sock, int family,
2042 int type, int protocol, int kern)
2043 {
2044 if (family != PF_INET || sock->sk == NULL)
2045 return 0;
2046 /*
2047 * Set the outbound netlbl.
2048 */
2049 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2050 }
2051
2052 /**
2053 * smack_socket_connect - connect access check
2054 * @sock: the socket
2055 * @sap: the other end
2056 * @addrlen: size of sap
2057 *
2058 * Verifies that a connection may be possible
2059 *
2060 * Returns 0 on success, and error code otherwise
2061 */
smack_socket_connect(struct socket * sock,struct sockaddr * sap,int addrlen)2062 static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2063 int addrlen)
2064 {
2065 if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
2066 return 0;
2067 if (addrlen < sizeof(struct sockaddr_in))
2068 return -EINVAL;
2069
2070 return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2071 }
2072
2073 /**
2074 * smack_flags_to_may - convert S_ to MAY_ values
2075 * @flags: the S_ value
2076 *
2077 * Returns the equivalent MAY_ value
2078 */
smack_flags_to_may(int flags)2079 static int smack_flags_to_may(int flags)
2080 {
2081 int may = 0;
2082
2083 if (flags & S_IRUGO)
2084 may |= MAY_READ;
2085 if (flags & S_IWUGO)
2086 may |= MAY_WRITE;
2087 if (flags & S_IXUGO)
2088 may |= MAY_EXEC;
2089
2090 return may;
2091 }
2092
2093 /**
2094 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2095 * @msg: the object
2096 *
2097 * Returns 0
2098 */
smack_msg_msg_alloc_security(struct msg_msg * msg)2099 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2100 {
2101 msg->security = smk_of_current();
2102 return 0;
2103 }
2104
2105 /**
2106 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2107 * @msg: the object
2108 *
2109 * Clears the blob pointer
2110 */
smack_msg_msg_free_security(struct msg_msg * msg)2111 static void smack_msg_msg_free_security(struct msg_msg *msg)
2112 {
2113 msg->security = NULL;
2114 }
2115
2116 /**
2117 * smack_of_shm - the smack pointer for the shm
2118 * @shp: the object
2119 *
2120 * Returns a pointer to the smack value
2121 */
smack_of_shm(struct shmid_kernel * shp)2122 static char *smack_of_shm(struct shmid_kernel *shp)
2123 {
2124 return (char *)shp->shm_perm.security;
2125 }
2126
2127 /**
2128 * smack_shm_alloc_security - Set the security blob for shm
2129 * @shp: the object
2130 *
2131 * Returns 0
2132 */
smack_shm_alloc_security(struct shmid_kernel * shp)2133 static int smack_shm_alloc_security(struct shmid_kernel *shp)
2134 {
2135 struct kern_ipc_perm *isp = &shp->shm_perm;
2136
2137 isp->security = smk_of_current();
2138 return 0;
2139 }
2140
2141 /**
2142 * smack_shm_free_security - Clear the security blob for shm
2143 * @shp: the object
2144 *
2145 * Clears the blob pointer
2146 */
smack_shm_free_security(struct shmid_kernel * shp)2147 static void smack_shm_free_security(struct shmid_kernel *shp)
2148 {
2149 struct kern_ipc_perm *isp = &shp->shm_perm;
2150
2151 isp->security = NULL;
2152 }
2153
2154 /**
2155 * smk_curacc_shm : check if current has access on shm
2156 * @shp : the object
2157 * @access : access requested
2158 *
2159 * Returns 0 if current has the requested access, error code otherwise
2160 */
smk_curacc_shm(struct shmid_kernel * shp,int access)2161 static int smk_curacc_shm(struct shmid_kernel *shp, int access)
2162 {
2163 char *ssp = smack_of_shm(shp);
2164 struct smk_audit_info ad;
2165
2166 #ifdef CONFIG_AUDIT
2167 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2168 ad.a.u.ipc_id = shp->shm_perm.id;
2169 #endif
2170 return smk_curacc(ssp, access, &ad);
2171 }
2172
2173 /**
2174 * smack_shm_associate - Smack access check for shm
2175 * @shp: the object
2176 * @shmflg: access requested
2177 *
2178 * Returns 0 if current has the requested access, error code otherwise
2179 */
smack_shm_associate(struct shmid_kernel * shp,int shmflg)2180 static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
2181 {
2182 int may;
2183
2184 may = smack_flags_to_may(shmflg);
2185 return smk_curacc_shm(shp, may);
2186 }
2187
2188 /**
2189 * smack_shm_shmctl - Smack access check for shm
2190 * @shp: the object
2191 * @cmd: what it wants to do
2192 *
2193 * Returns 0 if current has the requested access, error code otherwise
2194 */
smack_shm_shmctl(struct shmid_kernel * shp,int cmd)2195 static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
2196 {
2197 int may;
2198
2199 switch (cmd) {
2200 case IPC_STAT:
2201 case SHM_STAT:
2202 may = MAY_READ;
2203 break;
2204 case IPC_SET:
2205 case SHM_LOCK:
2206 case SHM_UNLOCK:
2207 case IPC_RMID:
2208 may = MAY_READWRITE;
2209 break;
2210 case IPC_INFO:
2211 case SHM_INFO:
2212 /*
2213 * System level information.
2214 */
2215 return 0;
2216 default:
2217 return -EINVAL;
2218 }
2219 return smk_curacc_shm(shp, may);
2220 }
2221
2222 /**
2223 * smack_shm_shmat - Smack access for shmat
2224 * @shp: the object
2225 * @shmaddr: unused
2226 * @shmflg: access requested
2227 *
2228 * Returns 0 if current has the requested access, error code otherwise
2229 */
smack_shm_shmat(struct shmid_kernel * shp,char __user * shmaddr,int shmflg)2230 static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
2231 int shmflg)
2232 {
2233 int may;
2234
2235 may = smack_flags_to_may(shmflg);
2236 return smk_curacc_shm(shp, may);
2237 }
2238
2239 /**
2240 * smack_of_sem - the smack pointer for the sem
2241 * @sma: the object
2242 *
2243 * Returns a pointer to the smack value
2244 */
smack_of_sem(struct sem_array * sma)2245 static char *smack_of_sem(struct sem_array *sma)
2246 {
2247 return (char *)sma->sem_perm.security;
2248 }
2249
2250 /**
2251 * smack_sem_alloc_security - Set the security blob for sem
2252 * @sma: the object
2253 *
2254 * Returns 0
2255 */
smack_sem_alloc_security(struct sem_array * sma)2256 static int smack_sem_alloc_security(struct sem_array *sma)
2257 {
2258 struct kern_ipc_perm *isp = &sma->sem_perm;
2259
2260 isp->security = smk_of_current();
2261 return 0;
2262 }
2263
2264 /**
2265 * smack_sem_free_security - Clear the security blob for sem
2266 * @sma: the object
2267 *
2268 * Clears the blob pointer
2269 */
smack_sem_free_security(struct sem_array * sma)2270 static void smack_sem_free_security(struct sem_array *sma)
2271 {
2272 struct kern_ipc_perm *isp = &sma->sem_perm;
2273
2274 isp->security = NULL;
2275 }
2276
2277 /**
2278 * smk_curacc_sem : check if current has access on sem
2279 * @sma : the object
2280 * @access : access requested
2281 *
2282 * Returns 0 if current has the requested access, error code otherwise
2283 */
smk_curacc_sem(struct sem_array * sma,int access)2284 static int smk_curacc_sem(struct sem_array *sma, int access)
2285 {
2286 char *ssp = smack_of_sem(sma);
2287 struct smk_audit_info ad;
2288
2289 #ifdef CONFIG_AUDIT
2290 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2291 ad.a.u.ipc_id = sma->sem_perm.id;
2292 #endif
2293 return smk_curacc(ssp, access, &ad);
2294 }
2295
2296 /**
2297 * smack_sem_associate - Smack access check for sem
2298 * @sma: the object
2299 * @semflg: access requested
2300 *
2301 * Returns 0 if current has the requested access, error code otherwise
2302 */
smack_sem_associate(struct sem_array * sma,int semflg)2303 static int smack_sem_associate(struct sem_array *sma, int semflg)
2304 {
2305 int may;
2306
2307 may = smack_flags_to_may(semflg);
2308 return smk_curacc_sem(sma, may);
2309 }
2310
2311 /**
2312 * smack_sem_shmctl - Smack access check for sem
2313 * @sma: the object
2314 * @cmd: what it wants to do
2315 *
2316 * Returns 0 if current has the requested access, error code otherwise
2317 */
smack_sem_semctl(struct sem_array * sma,int cmd)2318 static int smack_sem_semctl(struct sem_array *sma, int cmd)
2319 {
2320 int may;
2321
2322 switch (cmd) {
2323 case GETPID:
2324 case GETNCNT:
2325 case GETZCNT:
2326 case GETVAL:
2327 case GETALL:
2328 case IPC_STAT:
2329 case SEM_STAT:
2330 may = MAY_READ;
2331 break;
2332 case SETVAL:
2333 case SETALL:
2334 case IPC_RMID:
2335 case IPC_SET:
2336 may = MAY_READWRITE;
2337 break;
2338 case IPC_INFO:
2339 case SEM_INFO:
2340 /*
2341 * System level information
2342 */
2343 return 0;
2344 default:
2345 return -EINVAL;
2346 }
2347
2348 return smk_curacc_sem(sma, may);
2349 }
2350
2351 /**
2352 * smack_sem_semop - Smack checks of semaphore operations
2353 * @sma: the object
2354 * @sops: unused
2355 * @nsops: unused
2356 * @alter: unused
2357 *
2358 * Treated as read and write in all cases.
2359 *
2360 * Returns 0 if access is allowed, error code otherwise
2361 */
smack_sem_semop(struct sem_array * sma,struct sembuf * sops,unsigned nsops,int alter)2362 static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
2363 unsigned nsops, int alter)
2364 {
2365 return smk_curacc_sem(sma, MAY_READWRITE);
2366 }
2367
2368 /**
2369 * smack_msg_alloc_security - Set the security blob for msg
2370 * @msq: the object
2371 *
2372 * Returns 0
2373 */
smack_msg_queue_alloc_security(struct msg_queue * msq)2374 static int smack_msg_queue_alloc_security(struct msg_queue *msq)
2375 {
2376 struct kern_ipc_perm *kisp = &msq->q_perm;
2377
2378 kisp->security = smk_of_current();
2379 return 0;
2380 }
2381
2382 /**
2383 * smack_msg_free_security - Clear the security blob for msg
2384 * @msq: the object
2385 *
2386 * Clears the blob pointer
2387 */
smack_msg_queue_free_security(struct msg_queue * msq)2388 static void smack_msg_queue_free_security(struct msg_queue *msq)
2389 {
2390 struct kern_ipc_perm *kisp = &msq->q_perm;
2391
2392 kisp->security = NULL;
2393 }
2394
2395 /**
2396 * smack_of_msq - the smack pointer for the msq
2397 * @msq: the object
2398 *
2399 * Returns a pointer to the smack value
2400 */
smack_of_msq(struct msg_queue * msq)2401 static char *smack_of_msq(struct msg_queue *msq)
2402 {
2403 return (char *)msq->q_perm.security;
2404 }
2405
2406 /**
2407 * smk_curacc_msq : helper to check if current has access on msq
2408 * @msq : the msq
2409 * @access : access requested
2410 *
2411 * return 0 if current has access, error otherwise
2412 */
smk_curacc_msq(struct msg_queue * msq,int access)2413 static int smk_curacc_msq(struct msg_queue *msq, int access)
2414 {
2415 char *msp = smack_of_msq(msq);
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 = msq->q_perm.id;
2421 #endif
2422 return smk_curacc(msp, access, &ad);
2423 }
2424
2425 /**
2426 * smack_msg_queue_associate - Smack access check for msg_queue
2427 * @msq: the object
2428 * @msqflg: access requested
2429 *
2430 * Returns 0 if current has the requested access, error code otherwise
2431 */
smack_msg_queue_associate(struct msg_queue * msq,int msqflg)2432 static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
2433 {
2434 int may;
2435
2436 may = smack_flags_to_may(msqflg);
2437 return smk_curacc_msq(msq, may);
2438 }
2439
2440 /**
2441 * smack_msg_queue_msgctl - Smack access check for msg_queue
2442 * @msq: the object
2443 * @cmd: what it wants to do
2444 *
2445 * Returns 0 if current has the requested access, error code otherwise
2446 */
smack_msg_queue_msgctl(struct msg_queue * msq,int cmd)2447 static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
2448 {
2449 int may;
2450
2451 switch (cmd) {
2452 case IPC_STAT:
2453 case MSG_STAT:
2454 may = MAY_READ;
2455 break;
2456 case IPC_SET:
2457 case IPC_RMID:
2458 may = MAY_READWRITE;
2459 break;
2460 case IPC_INFO:
2461 case MSG_INFO:
2462 /*
2463 * System level information
2464 */
2465 return 0;
2466 default:
2467 return -EINVAL;
2468 }
2469
2470 return smk_curacc_msq(msq, may);
2471 }
2472
2473 /**
2474 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2475 * @msq: the object
2476 * @msg: unused
2477 * @msqflg: access requested
2478 *
2479 * Returns 0 if current has the requested access, error code otherwise
2480 */
smack_msg_queue_msgsnd(struct msg_queue * msq,struct msg_msg * msg,int msqflg)2481 static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
2482 int msqflg)
2483 {
2484 int may;
2485
2486 may = smack_flags_to_may(msqflg);
2487 return smk_curacc_msq(msq, may);
2488 }
2489
2490 /**
2491 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2492 * @msq: the object
2493 * @msg: unused
2494 * @target: unused
2495 * @type: unused
2496 * @mode: unused
2497 *
2498 * Returns 0 if current has read and write access, error code otherwise
2499 */
smack_msg_queue_msgrcv(struct msg_queue * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)2500 static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
2501 struct task_struct *target, long type, int mode)
2502 {
2503 return smk_curacc_msq(msq, MAY_READWRITE);
2504 }
2505
2506 /**
2507 * smack_ipc_permission - Smack access for ipc_permission()
2508 * @ipp: the object permissions
2509 * @flag: access requested
2510 *
2511 * Returns 0 if current has read and write access, error code otherwise
2512 */
smack_ipc_permission(struct kern_ipc_perm * ipp,short flag)2513 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
2514 {
2515 char *isp = ipp->security;
2516 int may = smack_flags_to_may(flag);
2517 struct smk_audit_info ad;
2518
2519 #ifdef CONFIG_AUDIT
2520 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2521 ad.a.u.ipc_id = ipp->id;
2522 #endif
2523 return smk_curacc(isp, may, &ad);
2524 }
2525
2526 /**
2527 * smack_ipc_getsecid - Extract smack security id
2528 * @ipp: the object permissions
2529 * @secid: where result will be saved
2530 */
smack_ipc_getsecid(struct kern_ipc_perm * ipp,u32 * secid)2531 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
2532 {
2533 char *smack = ipp->security;
2534
2535 *secid = smack_to_secid(smack);
2536 }
2537
2538 /**
2539 * smack_d_instantiate - Make sure the blob is correct on an inode
2540 * @opt_dentry: dentry where inode will be attached
2541 * @inode: the object
2542 *
2543 * Set the inode's security blob if it hasn't been done already.
2544 */
smack_d_instantiate(struct dentry * opt_dentry,struct inode * inode)2545 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
2546 {
2547 struct super_block *sbp;
2548 struct superblock_smack *sbsp;
2549 struct inode_smack *isp;
2550 char *csp = smk_of_current();
2551 char *fetched;
2552 char *final;
2553 char trattr[TRANS_TRUE_SIZE];
2554 int transflag = 0;
2555 struct dentry *dp;
2556
2557 if (inode == NULL)
2558 return;
2559
2560 isp = inode->i_security;
2561
2562 mutex_lock(&isp->smk_lock);
2563 /*
2564 * If the inode is already instantiated
2565 * take the quick way out
2566 */
2567 if (isp->smk_flags & SMK_INODE_INSTANT)
2568 goto unlockandout;
2569
2570 sbp = inode->i_sb;
2571 sbsp = sbp->s_security;
2572 /*
2573 * We're going to use the superblock default label
2574 * if there's no label on the file.
2575 */
2576 final = sbsp->smk_default;
2577
2578 /*
2579 * If this is the root inode the superblock
2580 * may be in the process of initialization.
2581 * If that is the case use the root value out
2582 * of the superblock.
2583 */
2584 if (opt_dentry->d_parent == opt_dentry) {
2585 isp->smk_inode = sbsp->smk_root;
2586 isp->smk_flags |= SMK_INODE_INSTANT;
2587 goto unlockandout;
2588 }
2589
2590 /*
2591 * This is pretty hackish.
2592 * Casey says that we shouldn't have to do
2593 * file system specific code, but it does help
2594 * with keeping it simple.
2595 */
2596 switch (sbp->s_magic) {
2597 case SMACK_MAGIC:
2598 /*
2599 * Casey says that it's a little embarrassing
2600 * that the smack file system doesn't do
2601 * extended attributes.
2602 */
2603 final = smack_known_star.smk_known;
2604 break;
2605 case PIPEFS_MAGIC:
2606 /*
2607 * Casey says pipes are easy (?)
2608 */
2609 final = smack_known_star.smk_known;
2610 break;
2611 case DEVPTS_SUPER_MAGIC:
2612 /*
2613 * devpts seems content with the label of the task.
2614 * Programs that change smack have to treat the
2615 * pty with respect.
2616 */
2617 final = csp;
2618 break;
2619 case SOCKFS_MAGIC:
2620 /*
2621 * Socket access is controlled by the socket
2622 * structures associated with the task involved.
2623 */
2624 final = smack_known_star.smk_known;
2625 break;
2626 case PROC_SUPER_MAGIC:
2627 /*
2628 * Casey says procfs appears not to care.
2629 * The superblock default suffices.
2630 */
2631 break;
2632 case TMPFS_MAGIC:
2633 /*
2634 * Device labels should come from the filesystem,
2635 * but watch out, because they're volitile,
2636 * getting recreated on every reboot.
2637 */
2638 final = smack_known_star.smk_known;
2639 /*
2640 * No break.
2641 *
2642 * If a smack value has been set we want to use it,
2643 * but since tmpfs isn't giving us the opportunity
2644 * to set mount options simulate setting the
2645 * superblock default.
2646 */
2647 default:
2648 /*
2649 * This isn't an understood special case.
2650 * Get the value from the xattr.
2651 */
2652
2653 /*
2654 * UNIX domain sockets use lower level socket data.
2655 */
2656 if (S_ISSOCK(inode->i_mode)) {
2657 final = smack_known_star.smk_known;
2658 break;
2659 }
2660 /*
2661 * No xattr support means, alas, no SMACK label.
2662 * Use the aforeapplied default.
2663 * It would be curious if the label of the task
2664 * does not match that assigned.
2665 */
2666 if (inode->i_op->getxattr == NULL)
2667 break;
2668 /*
2669 * Get the dentry for xattr.
2670 */
2671 dp = dget(opt_dentry);
2672 fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
2673 if (fetched != NULL) {
2674 final = fetched;
2675 if (S_ISDIR(inode->i_mode)) {
2676 trattr[0] = '\0';
2677 inode->i_op->getxattr(dp,
2678 XATTR_NAME_SMACKTRANSMUTE,
2679 trattr, TRANS_TRUE_SIZE);
2680 if (strncmp(trattr, TRANS_TRUE,
2681 TRANS_TRUE_SIZE) == 0)
2682 transflag = SMK_INODE_TRANSMUTE;
2683 }
2684 }
2685 isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
2686 isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
2687
2688 dput(dp);
2689 break;
2690 }
2691
2692 if (final == NULL)
2693 isp->smk_inode = csp;
2694 else
2695 isp->smk_inode = final;
2696
2697 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
2698
2699 unlockandout:
2700 mutex_unlock(&isp->smk_lock);
2701 return;
2702 }
2703
2704 /**
2705 * smack_getprocattr - Smack process attribute access
2706 * @p: the object task
2707 * @name: the name of the attribute in /proc/.../attr
2708 * @value: where to put the result
2709 *
2710 * Places a copy of the task Smack into value
2711 *
2712 * Returns the length of the smack label or an error code
2713 */
smack_getprocattr(struct task_struct * p,char * name,char ** value)2714 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2715 {
2716 char *cp;
2717 int slen;
2718
2719 if (strcmp(name, "current") != 0)
2720 return -EINVAL;
2721
2722 cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL);
2723 if (cp == NULL)
2724 return -ENOMEM;
2725
2726 slen = strlen(cp);
2727 *value = cp;
2728 return slen;
2729 }
2730
2731 /**
2732 * smack_setprocattr - Smack process attribute setting
2733 * @p: the object task
2734 * @name: the name of the attribute in /proc/.../attr
2735 * @value: the value to set
2736 * @size: the size of the value
2737 *
2738 * Sets the Smack value of the task. Only setting self
2739 * is permitted and only with privilege
2740 *
2741 * Returns the length of the smack label or an error code
2742 */
smack_setprocattr(struct task_struct * p,char * name,void * value,size_t size)2743 static int smack_setprocattr(struct task_struct *p, char *name,
2744 void *value, size_t size)
2745 {
2746 int rc;
2747 struct task_smack *tsp;
2748 struct task_smack *oldtsp;
2749 struct cred *new;
2750 char *newsmack;
2751
2752 /*
2753 * Changing another process' Smack value is too dangerous
2754 * and supports no sane use case.
2755 */
2756 if (p != current)
2757 return -EPERM;
2758
2759 if (!capable(CAP_MAC_ADMIN))
2760 return -EPERM;
2761
2762 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2763 return -EINVAL;
2764
2765 if (strcmp(name, "current") != 0)
2766 return -EINVAL;
2767
2768 newsmack = smk_import(value, size);
2769 if (newsmack == NULL)
2770 return -EINVAL;
2771
2772 /*
2773 * No process is ever allowed the web ("@") label.
2774 */
2775 if (newsmack == smack_known_web.smk_known)
2776 return -EPERM;
2777
2778 oldtsp = p->cred->security;
2779 new = prepare_creds();
2780 if (new == NULL)
2781 return -ENOMEM;
2782
2783 tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
2784 if (tsp == NULL) {
2785 kfree(new);
2786 return -ENOMEM;
2787 }
2788 rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
2789 if (rc != 0)
2790 return rc;
2791
2792 new->security = tsp;
2793 commit_creds(new);
2794 return size;
2795 }
2796
2797 /**
2798 * smack_unix_stream_connect - Smack access on UDS
2799 * @sock: one sock
2800 * @other: the other sock
2801 * @newsk: unused
2802 *
2803 * Return 0 if a subject with the smack of sock could access
2804 * an object with the smack of other, otherwise an error code
2805 */
smack_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)2806 static int smack_unix_stream_connect(struct sock *sock,
2807 struct sock *other, struct sock *newsk)
2808 {
2809 struct socket_smack *ssp = sock->sk_security;
2810 struct socket_smack *osp = other->sk_security;
2811 struct socket_smack *nsp = newsk->sk_security;
2812 struct smk_audit_info ad;
2813 int rc = 0;
2814
2815 #ifdef CONFIG_AUDIT
2816 struct lsm_network_audit net;
2817
2818 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2819 smk_ad_setfield_u_net_sk(&ad, other);
2820 #endif
2821
2822 if (!capable(CAP_MAC_OVERRIDE))
2823 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2824
2825 /*
2826 * Cross reference the peer labels for SO_PEERSEC.
2827 */
2828 if (rc == 0) {
2829 nsp->smk_packet = ssp->smk_out;
2830 ssp->smk_packet = osp->smk_out;
2831 }
2832
2833 return rc;
2834 }
2835
2836 /**
2837 * smack_unix_may_send - Smack access on UDS
2838 * @sock: one socket
2839 * @other: the other socket
2840 *
2841 * Return 0 if a subject with the smack of sock could access
2842 * an object with the smack of other, otherwise an error code
2843 */
smack_unix_may_send(struct socket * sock,struct socket * other)2844 static int smack_unix_may_send(struct socket *sock, struct socket *other)
2845 {
2846 struct socket_smack *ssp = sock->sk->sk_security;
2847 struct socket_smack *osp = other->sk->sk_security;
2848 struct smk_audit_info ad;
2849 int rc = 0;
2850
2851 #ifdef CONFIG_AUDIT
2852 struct lsm_network_audit net;
2853
2854 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2855 smk_ad_setfield_u_net_sk(&ad, other->sk);
2856 #endif
2857
2858 if (!capable(CAP_MAC_OVERRIDE))
2859 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2860
2861 return rc;
2862 }
2863
2864 /**
2865 * smack_socket_sendmsg - Smack check based on destination host
2866 * @sock: the socket
2867 * @msg: the message
2868 * @size: the size of the message
2869 *
2870 * Return 0 if the current subject can write to the destination
2871 * host. This is only a question if the destination is a single
2872 * label host.
2873 */
smack_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)2874 static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
2875 int size)
2876 {
2877 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
2878
2879 /*
2880 * Perfectly reasonable for this to be NULL
2881 */
2882 if (sip == NULL || sip->sin_family != AF_INET)
2883 return 0;
2884
2885 return smack_netlabel_send(sock->sk, sip);
2886 }
2887
2888 /**
2889 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
2890 * @sap: netlabel secattr
2891 * @ssp: socket security information
2892 *
2893 * Returns a pointer to a Smack label found on the label list.
2894 */
smack_from_secattr(struct netlbl_lsm_secattr * sap,struct socket_smack * ssp)2895 static char *smack_from_secattr(struct netlbl_lsm_secattr *sap,
2896 struct socket_smack *ssp)
2897 {
2898 struct smack_known *skp;
2899 char smack[SMK_LABELLEN];
2900 char *sp;
2901 int pcat;
2902
2903 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
2904 /*
2905 * Looks like a CIPSO packet.
2906 * If there are flags but no level netlabel isn't
2907 * behaving the way we expect it to.
2908 *
2909 * Get the categories, if any
2910 * Without guidance regarding the smack value
2911 * for the packet fall back on the network
2912 * ambient value.
2913 */
2914 memset(smack, '\0', SMK_LABELLEN);
2915 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2916 for (pcat = -1;;) {
2917 pcat = netlbl_secattr_catmap_walk(
2918 sap->attr.mls.cat, pcat + 1);
2919 if (pcat < 0)
2920 break;
2921 smack_catset_bit(pcat, smack);
2922 }
2923 /*
2924 * If it is CIPSO using smack direct mapping
2925 * we are already done. WeeHee.
2926 */
2927 if (sap->attr.mls.lvl == smack_cipso_direct) {
2928 /*
2929 * The label sent is usually on the label list.
2930 *
2931 * If it is not we may still want to allow the
2932 * delivery.
2933 *
2934 * If the recipient is accepting all packets
2935 * because it is using the star ("*") label
2936 * for SMACK64IPIN provide the web ("@") label
2937 * so that a directed response will succeed.
2938 * This is not very correct from a MAC point
2939 * of view, but gets around the problem that
2940 * locking prevents adding the newly discovered
2941 * label to the list.
2942 * The case where the recipient is not using
2943 * the star label should obviously fail.
2944 * The easy way to do this is to provide the
2945 * star label as the subject label.
2946 */
2947 skp = smk_find_entry(smack);
2948 if (skp != NULL)
2949 return skp->smk_known;
2950 if (ssp != NULL &&
2951 ssp->smk_in == smack_known_star.smk_known)
2952 return smack_known_web.smk_known;
2953 return smack_known_star.smk_known;
2954 }
2955 /*
2956 * Look it up in the supplied table if it is not
2957 * a direct mapping.
2958 */
2959 sp = smack_from_cipso(sap->attr.mls.lvl, smack);
2960 if (sp != NULL)
2961 return sp;
2962 if (ssp != NULL && ssp->smk_in == smack_known_star.smk_known)
2963 return smack_known_web.smk_known;
2964 return smack_known_star.smk_known;
2965 }
2966 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
2967 /*
2968 * Looks like a fallback, which gives us a secid.
2969 */
2970 sp = smack_from_secid(sap->attr.secid);
2971 /*
2972 * This has got to be a bug because it is
2973 * impossible to specify a fallback without
2974 * specifying the label, which will ensure
2975 * it has a secid, and the only way to get a
2976 * secid is from a fallback.
2977 */
2978 BUG_ON(sp == NULL);
2979 return sp;
2980 }
2981 /*
2982 * Without guidance regarding the smack value
2983 * for the packet fall back on the network
2984 * ambient value.
2985 */
2986 return smack_net_ambient;
2987 }
2988
2989 /**
2990 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2991 * @sk: socket
2992 * @skb: packet
2993 *
2994 * Returns 0 if the packet should be delivered, an error code otherwise
2995 */
smack_socket_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)2996 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2997 {
2998 struct netlbl_lsm_secattr secattr;
2999 struct socket_smack *ssp = sk->sk_security;
3000 char *csp;
3001 int rc;
3002 struct smk_audit_info ad;
3003 #ifdef CONFIG_AUDIT
3004 struct lsm_network_audit net;
3005 #endif
3006 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
3007 return 0;
3008
3009 /*
3010 * Translate what netlabel gave us.
3011 */
3012 netlbl_secattr_init(&secattr);
3013
3014 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3015 if (rc == 0)
3016 csp = smack_from_secattr(&secattr, ssp);
3017 else
3018 csp = smack_net_ambient;
3019
3020 netlbl_secattr_destroy(&secattr);
3021
3022 #ifdef CONFIG_AUDIT
3023 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3024 ad.a.u.net->family = sk->sk_family;
3025 ad.a.u.net->netif = skb->skb_iif;
3026 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3027 #endif
3028 /*
3029 * Receiving a packet requires that the other end
3030 * be able to write here. Read access is not required.
3031 * This is the simplist possible security model
3032 * for networking.
3033 */
3034 rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
3035 if (rc != 0)
3036 netlbl_skbuff_err(skb, rc, 0);
3037 return rc;
3038 }
3039
3040 /**
3041 * smack_socket_getpeersec_stream - pull in packet label
3042 * @sock: the socket
3043 * @optval: user's destination
3044 * @optlen: size thereof
3045 * @len: max thereof
3046 *
3047 * returns zero on success, an error code otherwise
3048 */
smack_socket_getpeersec_stream(struct socket * sock,char __user * optval,int __user * optlen,unsigned len)3049 static int smack_socket_getpeersec_stream(struct socket *sock,
3050 char __user *optval,
3051 int __user *optlen, unsigned len)
3052 {
3053 struct socket_smack *ssp;
3054 char *rcp = "";
3055 int slen = 1;
3056 int rc = 0;
3057
3058 ssp = sock->sk->sk_security;
3059 if (ssp->smk_packet != NULL) {
3060 rcp = ssp->smk_packet;
3061 slen = strlen(rcp) + 1;
3062 }
3063
3064 if (slen > len)
3065 rc = -ERANGE;
3066 else if (copy_to_user(optval, rcp, slen) != 0)
3067 rc = -EFAULT;
3068
3069 if (put_user(slen, optlen) != 0)
3070 rc = -EFAULT;
3071
3072 return rc;
3073 }
3074
3075
3076 /**
3077 * smack_socket_getpeersec_dgram - pull in packet label
3078 * @sock: the peer socket
3079 * @skb: packet data
3080 * @secid: pointer to where to put the secid of the packet
3081 *
3082 * Sets the netlabel socket state on sk from parent
3083 */
smack_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)3084 static int smack_socket_getpeersec_dgram(struct socket *sock,
3085 struct sk_buff *skb, u32 *secid)
3086
3087 {
3088 struct netlbl_lsm_secattr secattr;
3089 struct socket_smack *ssp = NULL;
3090 char *sp;
3091 int family = PF_UNSPEC;
3092 u32 s = 0; /* 0 is the invalid secid */
3093 int rc;
3094
3095 if (skb != NULL) {
3096 if (skb->protocol == htons(ETH_P_IP))
3097 family = PF_INET;
3098 else if (skb->protocol == htons(ETH_P_IPV6))
3099 family = PF_INET6;
3100 }
3101 if (family == PF_UNSPEC && sock != NULL)
3102 family = sock->sk->sk_family;
3103
3104 if (family == PF_UNIX) {
3105 ssp = sock->sk->sk_security;
3106 s = smack_to_secid(ssp->smk_out);
3107 } else if (family == PF_INET || family == PF_INET6) {
3108 /*
3109 * Translate what netlabel gave us.
3110 */
3111 if (sock != NULL && sock->sk != NULL)
3112 ssp = sock->sk->sk_security;
3113 netlbl_secattr_init(&secattr);
3114 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3115 if (rc == 0) {
3116 sp = smack_from_secattr(&secattr, ssp);
3117 s = smack_to_secid(sp);
3118 }
3119 netlbl_secattr_destroy(&secattr);
3120 }
3121 *secid = s;
3122 if (s == 0)
3123 return -EINVAL;
3124 return 0;
3125 }
3126
3127 /**
3128 * smack_sock_graft - Initialize a newly created socket with an existing sock
3129 * @sk: child sock
3130 * @parent: parent socket
3131 *
3132 * Set the smk_{in,out} state of an existing sock based on the process that
3133 * is creating the new socket.
3134 */
smack_sock_graft(struct sock * sk,struct socket * parent)3135 static void smack_sock_graft(struct sock *sk, struct socket *parent)
3136 {
3137 struct socket_smack *ssp;
3138
3139 if (sk == NULL ||
3140 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3141 return;
3142
3143 ssp = sk->sk_security;
3144 ssp->smk_in = ssp->smk_out = smk_of_current();
3145 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
3146 }
3147
3148 /**
3149 * smack_inet_conn_request - Smack access check on connect
3150 * @sk: socket involved
3151 * @skb: packet
3152 * @req: unused
3153 *
3154 * Returns 0 if a task with the packet label could write to
3155 * the socket, otherwise an error code
3156 */
smack_inet_conn_request(struct sock * sk,struct sk_buff * skb,struct request_sock * req)3157 static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
3158 struct request_sock *req)
3159 {
3160 u16 family = sk->sk_family;
3161 struct socket_smack *ssp = sk->sk_security;
3162 struct netlbl_lsm_secattr secattr;
3163 struct sockaddr_in addr;
3164 struct iphdr *hdr;
3165 char *sp;
3166 int rc;
3167 struct smk_audit_info ad;
3168 #ifdef CONFIG_AUDIT
3169 struct lsm_network_audit net;
3170 #endif
3171
3172 /* handle mapped IPv4 packets arriving via IPv6 sockets */
3173 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
3174 family = PF_INET;
3175
3176 netlbl_secattr_init(&secattr);
3177 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3178 if (rc == 0)
3179 sp = smack_from_secattr(&secattr, ssp);
3180 else
3181 sp = smack_known_huh.smk_known;
3182 netlbl_secattr_destroy(&secattr);
3183
3184 #ifdef CONFIG_AUDIT
3185 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3186 ad.a.u.net->family = family;
3187 ad.a.u.net->netif = skb->skb_iif;
3188 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3189 #endif
3190 /*
3191 * Receiving a packet requires that the other end be able to write
3192 * here. Read access is not required.
3193 */
3194 rc = smk_access(sp, ssp->smk_in, MAY_WRITE, &ad);
3195 if (rc != 0)
3196 return rc;
3197
3198 /*
3199 * Save the peer's label in the request_sock so we can later setup
3200 * smk_packet in the child socket so that SO_PEERCRED can report it.
3201 */
3202 req->peer_secid = smack_to_secid(sp);
3203
3204 /*
3205 * We need to decide if we want to label the incoming connection here
3206 * if we do we only need to label the request_sock and the stack will
3207 * propagate the wire-label to the sock when it is created.
3208 */
3209 hdr = ip_hdr(skb);
3210 addr.sin_addr.s_addr = hdr->saddr;
3211 rcu_read_lock();
3212 if (smack_host_label(&addr) == NULL) {
3213 rcu_read_unlock();
3214 netlbl_secattr_init(&secattr);
3215 smack_to_secattr(sp, &secattr);
3216 rc = netlbl_req_setattr(req, &secattr);
3217 netlbl_secattr_destroy(&secattr);
3218 } else {
3219 rcu_read_unlock();
3220 netlbl_req_delattr(req);
3221 }
3222
3223 return rc;
3224 }
3225
3226 /**
3227 * smack_inet_csk_clone - Copy the connection information to the new socket
3228 * @sk: the new socket
3229 * @req: the connection's request_sock
3230 *
3231 * Transfer the connection's peer label to the newly created socket.
3232 */
smack_inet_csk_clone(struct sock * sk,const struct request_sock * req)3233 static void smack_inet_csk_clone(struct sock *sk,
3234 const struct request_sock *req)
3235 {
3236 struct socket_smack *ssp = sk->sk_security;
3237
3238 if (req->peer_secid != 0)
3239 ssp->smk_packet = smack_from_secid(req->peer_secid);
3240 else
3241 ssp->smk_packet = NULL;
3242 }
3243
3244 /*
3245 * Key management security hooks
3246 *
3247 * Casey has not tested key support very heavily.
3248 * The permission check is most likely too restrictive.
3249 * If you care about keys please have a look.
3250 */
3251 #ifdef CONFIG_KEYS
3252
3253 /**
3254 * smack_key_alloc - Set the key security blob
3255 * @key: object
3256 * @cred: the credentials to use
3257 * @flags: unused
3258 *
3259 * No allocation required
3260 *
3261 * Returns 0
3262 */
smack_key_alloc(struct key * key,const struct cred * cred,unsigned long flags)3263 static int smack_key_alloc(struct key *key, const struct cred *cred,
3264 unsigned long flags)
3265 {
3266 key->security = smk_of_task(cred->security);
3267 return 0;
3268 }
3269
3270 /**
3271 * smack_key_free - Clear the key security blob
3272 * @key: the object
3273 *
3274 * Clear the blob pointer
3275 */
smack_key_free(struct key * key)3276 static void smack_key_free(struct key *key)
3277 {
3278 key->security = NULL;
3279 }
3280
3281 /*
3282 * smack_key_permission - Smack access on a key
3283 * @key_ref: gets to the object
3284 * @cred: the credentials to use
3285 * @perm: unused
3286 *
3287 * Return 0 if the task has read and write to the object,
3288 * an error code otherwise
3289 */
smack_key_permission(key_ref_t key_ref,const struct cred * cred,key_perm_t perm)3290 static int smack_key_permission(key_ref_t key_ref,
3291 const struct cred *cred, key_perm_t perm)
3292 {
3293 struct key *keyp;
3294 struct smk_audit_info ad;
3295 char *tsp = smk_of_task(cred->security);
3296
3297 keyp = key_ref_to_ptr(key_ref);
3298 if (keyp == NULL)
3299 return -EINVAL;
3300 /*
3301 * If the key hasn't been initialized give it access so that
3302 * it may do so.
3303 */
3304 if (keyp->security == NULL)
3305 return 0;
3306 /*
3307 * This should not occur
3308 */
3309 if (tsp == NULL)
3310 return -EACCES;
3311 #ifdef CONFIG_AUDIT
3312 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
3313 ad.a.u.key_struct.key = keyp->serial;
3314 ad.a.u.key_struct.key_desc = keyp->description;
3315 #endif
3316 return smk_access(tsp, keyp->security,
3317 MAY_READWRITE, &ad);
3318 }
3319 #endif /* CONFIG_KEYS */
3320
3321 /*
3322 * Smack Audit hooks
3323 *
3324 * Audit requires a unique representation of each Smack specific
3325 * rule. This unique representation is used to distinguish the
3326 * object to be audited from remaining kernel objects and also
3327 * works as a glue between the audit hooks.
3328 *
3329 * Since repository entries are added but never deleted, we'll use
3330 * the smack_known label address related to the given audit rule as
3331 * the needed unique representation. This also better fits the smack
3332 * model where nearly everything is a label.
3333 */
3334 #ifdef CONFIG_AUDIT
3335
3336 /**
3337 * smack_audit_rule_init - Initialize a smack audit rule
3338 * @field: audit rule fields given from user-space (audit.h)
3339 * @op: required testing operator (=, !=, >, <, ...)
3340 * @rulestr: smack label to be audited
3341 * @vrule: pointer to save our own audit rule representation
3342 *
3343 * Prepare to audit cases where (@field @op @rulestr) is true.
3344 * The label to be audited is created if necessay.
3345 */
smack_audit_rule_init(u32 field,u32 op,char * rulestr,void ** vrule)3346 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3347 {
3348 char **rule = (char **)vrule;
3349 *rule = NULL;
3350
3351 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3352 return -EINVAL;
3353
3354 if (op != Audit_equal && op != Audit_not_equal)
3355 return -EINVAL;
3356
3357 *rule = smk_import(rulestr, 0);
3358
3359 return 0;
3360 }
3361
3362 /**
3363 * smack_audit_rule_known - Distinguish Smack audit rules
3364 * @krule: rule of interest, in Audit kernel representation format
3365 *
3366 * This is used to filter Smack rules from remaining Audit ones.
3367 * If it's proved that this rule belongs to us, the
3368 * audit_rule_match hook will be called to do the final judgement.
3369 */
smack_audit_rule_known(struct audit_krule * krule)3370 static int smack_audit_rule_known(struct audit_krule *krule)
3371 {
3372 struct audit_field *f;
3373 int i;
3374
3375 for (i = 0; i < krule->field_count; i++) {
3376 f = &krule->fields[i];
3377
3378 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
3379 return 1;
3380 }
3381
3382 return 0;
3383 }
3384
3385 /**
3386 * smack_audit_rule_match - Audit given object ?
3387 * @secid: security id for identifying the object to test
3388 * @field: audit rule flags given from user-space
3389 * @op: required testing operator
3390 * @vrule: smack internal rule presentation
3391 * @actx: audit context associated with the check
3392 *
3393 * The core Audit hook. It's used to take the decision of
3394 * whether to audit or not to audit a given object.
3395 */
smack_audit_rule_match(u32 secid,u32 field,u32 op,void * vrule,struct audit_context * actx)3396 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
3397 struct audit_context *actx)
3398 {
3399 char *smack;
3400 char *rule = vrule;
3401
3402 if (!rule) {
3403 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
3404 "Smack: missing rule\n");
3405 return -ENOENT;
3406 }
3407
3408 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3409 return 0;
3410
3411 smack = smack_from_secid(secid);
3412
3413 /*
3414 * No need to do string comparisons. If a match occurs,
3415 * both pointers will point to the same smack_known
3416 * label.
3417 */
3418 if (op == Audit_equal)
3419 return (rule == smack);
3420 if (op == Audit_not_equal)
3421 return (rule != smack);
3422
3423 return 0;
3424 }
3425
3426 /**
3427 * smack_audit_rule_free - free smack rule representation
3428 * @vrule: rule to be freed.
3429 *
3430 * No memory was allocated.
3431 */
smack_audit_rule_free(void * vrule)3432 static void smack_audit_rule_free(void *vrule)
3433 {
3434 /* No-op */
3435 }
3436
3437 #endif /* CONFIG_AUDIT */
3438
3439 /**
3440 * smack_secid_to_secctx - return the smack label for a secid
3441 * @secid: incoming integer
3442 * @secdata: destination
3443 * @seclen: how long it is
3444 *
3445 * Exists for networking code.
3446 */
smack_secid_to_secctx(u32 secid,char ** secdata,u32 * seclen)3447 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
3448 {
3449 char *sp = smack_from_secid(secid);
3450
3451 if (secdata)
3452 *secdata = sp;
3453 *seclen = strlen(sp);
3454 return 0;
3455 }
3456
3457 /**
3458 * smack_secctx_to_secid - return the secid for a smack label
3459 * @secdata: smack label
3460 * @seclen: how long result is
3461 * @secid: outgoing integer
3462 *
3463 * Exists for audit and networking code.
3464 */
smack_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)3465 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3466 {
3467 *secid = smack_to_secid(secdata);
3468 return 0;
3469 }
3470
3471 /**
3472 * smack_release_secctx - don't do anything.
3473 * @secdata: unused
3474 * @seclen: unused
3475 *
3476 * Exists to make sure nothing gets done, and properly
3477 */
smack_release_secctx(char * secdata,u32 seclen)3478 static void smack_release_secctx(char *secdata, u32 seclen)
3479 {
3480 }
3481
smack_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)3482 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
3483 {
3484 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
3485 }
3486
smack_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)3487 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
3488 {
3489 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
3490 }
3491
smack_inode_getsecctx(struct inode * inode,void ** ctx,u32 * ctxlen)3492 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
3493 {
3494 int len = 0;
3495 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
3496
3497 if (len < 0)
3498 return len;
3499 *ctxlen = len;
3500 return 0;
3501 }
3502
3503 struct security_operations smack_ops = {
3504 .name = "smack",
3505
3506 .ptrace_access_check = smack_ptrace_access_check,
3507 .ptrace_traceme = smack_ptrace_traceme,
3508 .syslog = smack_syslog,
3509
3510 .sb_alloc_security = smack_sb_alloc_security,
3511 .sb_free_security = smack_sb_free_security,
3512 .sb_copy_data = smack_sb_copy_data,
3513 .sb_kern_mount = smack_sb_kern_mount,
3514 .sb_statfs = smack_sb_statfs,
3515 .sb_mount = smack_sb_mount,
3516 .sb_umount = smack_sb_umount,
3517
3518 .bprm_set_creds = smack_bprm_set_creds,
3519 .bprm_committing_creds = smack_bprm_committing_creds,
3520 .bprm_secureexec = smack_bprm_secureexec,
3521
3522 .inode_alloc_security = smack_inode_alloc_security,
3523 .inode_free_security = smack_inode_free_security,
3524 .inode_init_security = smack_inode_init_security,
3525 .inode_link = smack_inode_link,
3526 .inode_unlink = smack_inode_unlink,
3527 .inode_rmdir = smack_inode_rmdir,
3528 .inode_rename = smack_inode_rename,
3529 .inode_permission = smack_inode_permission,
3530 .inode_setattr = smack_inode_setattr,
3531 .inode_getattr = smack_inode_getattr,
3532 .inode_setxattr = smack_inode_setxattr,
3533 .inode_post_setxattr = smack_inode_post_setxattr,
3534 .inode_getxattr = smack_inode_getxattr,
3535 .inode_removexattr = smack_inode_removexattr,
3536 .inode_getsecurity = smack_inode_getsecurity,
3537 .inode_setsecurity = smack_inode_setsecurity,
3538 .inode_listsecurity = smack_inode_listsecurity,
3539 .inode_getsecid = smack_inode_getsecid,
3540
3541 .file_permission = smack_file_permission,
3542 .file_alloc_security = smack_file_alloc_security,
3543 .file_free_security = smack_file_free_security,
3544 .file_ioctl = smack_file_ioctl,
3545 .file_lock = smack_file_lock,
3546 .file_fcntl = smack_file_fcntl,
3547 .file_mmap = smack_file_mmap,
3548 .file_set_fowner = smack_file_set_fowner,
3549 .file_send_sigiotask = smack_file_send_sigiotask,
3550 .file_receive = smack_file_receive,
3551
3552 .dentry_open = smack_dentry_open,
3553
3554 .cred_alloc_blank = smack_cred_alloc_blank,
3555 .cred_free = smack_cred_free,
3556 .cred_prepare = smack_cred_prepare,
3557 .cred_transfer = smack_cred_transfer,
3558 .kernel_act_as = smack_kernel_act_as,
3559 .kernel_create_files_as = smack_kernel_create_files_as,
3560 .task_setpgid = smack_task_setpgid,
3561 .task_getpgid = smack_task_getpgid,
3562 .task_getsid = smack_task_getsid,
3563 .task_getsecid = smack_task_getsecid,
3564 .task_setnice = smack_task_setnice,
3565 .task_setioprio = smack_task_setioprio,
3566 .task_getioprio = smack_task_getioprio,
3567 .task_setscheduler = smack_task_setscheduler,
3568 .task_getscheduler = smack_task_getscheduler,
3569 .task_movememory = smack_task_movememory,
3570 .task_kill = smack_task_kill,
3571 .task_wait = smack_task_wait,
3572 .task_to_inode = smack_task_to_inode,
3573
3574 .ipc_permission = smack_ipc_permission,
3575 .ipc_getsecid = smack_ipc_getsecid,
3576
3577 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
3578 .msg_msg_free_security = smack_msg_msg_free_security,
3579
3580 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
3581 .msg_queue_free_security = smack_msg_queue_free_security,
3582 .msg_queue_associate = smack_msg_queue_associate,
3583 .msg_queue_msgctl = smack_msg_queue_msgctl,
3584 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
3585 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
3586
3587 .shm_alloc_security = smack_shm_alloc_security,
3588 .shm_free_security = smack_shm_free_security,
3589 .shm_associate = smack_shm_associate,
3590 .shm_shmctl = smack_shm_shmctl,
3591 .shm_shmat = smack_shm_shmat,
3592
3593 .sem_alloc_security = smack_sem_alloc_security,
3594 .sem_free_security = smack_sem_free_security,
3595 .sem_associate = smack_sem_associate,
3596 .sem_semctl = smack_sem_semctl,
3597 .sem_semop = smack_sem_semop,
3598
3599 .d_instantiate = smack_d_instantiate,
3600
3601 .getprocattr = smack_getprocattr,
3602 .setprocattr = smack_setprocattr,
3603
3604 .unix_stream_connect = smack_unix_stream_connect,
3605 .unix_may_send = smack_unix_may_send,
3606
3607 .socket_post_create = smack_socket_post_create,
3608 .socket_connect = smack_socket_connect,
3609 .socket_sendmsg = smack_socket_sendmsg,
3610 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
3611 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
3612 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
3613 .sk_alloc_security = smack_sk_alloc_security,
3614 .sk_free_security = smack_sk_free_security,
3615 .sock_graft = smack_sock_graft,
3616 .inet_conn_request = smack_inet_conn_request,
3617 .inet_csk_clone = smack_inet_csk_clone,
3618
3619 /* key management security hooks */
3620 #ifdef CONFIG_KEYS
3621 .key_alloc = smack_key_alloc,
3622 .key_free = smack_key_free,
3623 .key_permission = smack_key_permission,
3624 #endif /* CONFIG_KEYS */
3625
3626 /* Audit hooks */
3627 #ifdef CONFIG_AUDIT
3628 .audit_rule_init = smack_audit_rule_init,
3629 .audit_rule_known = smack_audit_rule_known,
3630 .audit_rule_match = smack_audit_rule_match,
3631 .audit_rule_free = smack_audit_rule_free,
3632 #endif /* CONFIG_AUDIT */
3633
3634 .secid_to_secctx = smack_secid_to_secctx,
3635 .secctx_to_secid = smack_secctx_to_secid,
3636 .release_secctx = smack_release_secctx,
3637 .inode_notifysecctx = smack_inode_notifysecctx,
3638 .inode_setsecctx = smack_inode_setsecctx,
3639 .inode_getsecctx = smack_inode_getsecctx,
3640 };
3641
3642
init_smack_known_list(void)3643 static __init void init_smack_known_list(void)
3644 {
3645 /*
3646 * Initialize CIPSO locks
3647 */
3648 spin_lock_init(&smack_known_huh.smk_cipsolock);
3649 spin_lock_init(&smack_known_hat.smk_cipsolock);
3650 spin_lock_init(&smack_known_star.smk_cipsolock);
3651 spin_lock_init(&smack_known_floor.smk_cipsolock);
3652 spin_lock_init(&smack_known_invalid.smk_cipsolock);
3653 spin_lock_init(&smack_known_web.smk_cipsolock);
3654 /*
3655 * Initialize rule list locks
3656 */
3657 mutex_init(&smack_known_huh.smk_rules_lock);
3658 mutex_init(&smack_known_hat.smk_rules_lock);
3659 mutex_init(&smack_known_floor.smk_rules_lock);
3660 mutex_init(&smack_known_star.smk_rules_lock);
3661 mutex_init(&smack_known_invalid.smk_rules_lock);
3662 mutex_init(&smack_known_web.smk_rules_lock);
3663 /*
3664 * Initialize rule lists
3665 */
3666 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
3667 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
3668 INIT_LIST_HEAD(&smack_known_star.smk_rules);
3669 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
3670 INIT_LIST_HEAD(&smack_known_invalid.smk_rules);
3671 INIT_LIST_HEAD(&smack_known_web.smk_rules);
3672 /*
3673 * Create the known labels list
3674 */
3675 list_add(&smack_known_huh.list, &smack_known_list);
3676 list_add(&smack_known_hat.list, &smack_known_list);
3677 list_add(&smack_known_star.list, &smack_known_list);
3678 list_add(&smack_known_floor.list, &smack_known_list);
3679 list_add(&smack_known_invalid.list, &smack_known_list);
3680 list_add(&smack_known_web.list, &smack_known_list);
3681 }
3682
3683 /**
3684 * smack_init - initialize the smack system
3685 *
3686 * Returns 0
3687 */
smack_init(void)3688 static __init int smack_init(void)
3689 {
3690 struct cred *cred;
3691 struct task_smack *tsp;
3692
3693 if (!security_module_enable(&smack_ops))
3694 return 0;
3695
3696 tsp = new_task_smack(smack_known_floor.smk_known,
3697 smack_known_floor.smk_known, GFP_KERNEL);
3698 if (tsp == NULL)
3699 return -ENOMEM;
3700
3701 printk(KERN_INFO "Smack: Initializing.\n");
3702
3703 /*
3704 * Set the security state for the initial task.
3705 */
3706 cred = (struct cred *) current->cred;
3707 cred->security = tsp;
3708
3709 /* initialize the smack_known_list */
3710 init_smack_known_list();
3711
3712 /*
3713 * Register with LSM
3714 */
3715 if (register_security(&smack_ops))
3716 panic("smack: Unable to register with kernel.\n");
3717
3718 return 0;
3719 }
3720
3721 /*
3722 * Smack requires early initialization in order to label
3723 * all processes and objects when they are created.
3724 */
3725 security_initcall(smack_init);
3726