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Casey Schauflere114e472008-02-04 22:29:50 -08001/*
2 * Simplified MAC Kernel (smack) security module
3 *
4 * This file contains the smack hook function implementations.
5 *
6 * Author:
7 * Casey Schaufler <casey@schaufler-ca.com>
8 *
9 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
Paul Moore07feee82009-03-27 17:10:54 -040010 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
11 * Paul Moore <paul.moore@hp.com>
Casey Schauflere114e472008-02-04 22:29:50 -080012 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2,
15 * as published by the Free Software Foundation.
16 */
17
18#include <linux/xattr.h>
19#include <linux/pagemap.h>
20#include <linux/mount.h>
21#include <linux/stat.h>
Casey Schauflere114e472008-02-04 22:29:50 -080022#include <linux/kd.h>
23#include <asm/ioctls.h>
Paul Moore07feee82009-03-27 17:10:54 -040024#include <linux/ip.h>
Casey Schauflere114e472008-02-04 22:29:50 -080025#include <linux/tcp.h>
26#include <linux/udp.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090027#include <linux/slab.h>
Casey Schauflere114e472008-02-04 22:29:50 -080028#include <linux/mutex.h>
29#include <linux/pipe_fs_i.h>
30#include <net/netlabel.h>
31#include <net/cipso_ipv4.h>
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +100032#include <linux/audit.h>
Nick Black1fd73172009-09-22 16:43:33 -070033#include <linux/magic.h>
Casey Schauflere114e472008-02-04 22:29:50 -080034#include "smack.h"
35
David Howellsc69e8d92008-11-14 10:39:19 +110036#define task_security(task) (task_cred_xxx((task), security))
37
Casey Schauflere114e472008-02-04 22:29:50 -080038/**
39 * smk_fetch - Fetch the smack label from a file.
40 * @ip: a pointer to the inode
41 * @dp: a pointer to the dentry
42 *
43 * Returns a pointer to the master list entry for the Smack label
44 * or NULL if there was no label to fetch.
45 */
46static char *smk_fetch(struct inode *ip, struct dentry *dp)
47{
48 int rc;
49 char in[SMK_LABELLEN];
50
51 if (ip->i_op->getxattr == NULL)
52 return NULL;
53
54 rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN);
55 if (rc < 0)
56 return NULL;
57
58 return smk_import(in, rc);
59}
60
61/**
62 * new_inode_smack - allocate an inode security blob
63 * @smack: a pointer to the Smack label to use in the blob
64 *
65 * Returns the new blob or NULL if there's no memory available
66 */
67struct inode_smack *new_inode_smack(char *smack)
68{
69 struct inode_smack *isp;
70
71 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
72 if (isp == NULL)
73 return NULL;
74
75 isp->smk_inode = smack;
76 isp->smk_flags = 0;
77 mutex_init(&isp->smk_lock);
78
79 return isp;
80}
81
82/*
83 * LSM hooks.
84 * We he, that is fun!
85 */
86
87/**
Ingo Molnar9e488582009-05-07 19:26:19 +100088 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
Casey Schauflere114e472008-02-04 22:29:50 -080089 * @ctp: child task pointer
Randy Dunlap251a2a92009-02-18 11:42:33 -080090 * @mode: ptrace attachment mode
Casey Schauflere114e472008-02-04 22:29:50 -080091 *
92 * Returns 0 if access is OK, an error code otherwise
93 *
94 * Do the capability checks, and require read and write.
95 */
Ingo Molnar9e488582009-05-07 19:26:19 +100096static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
Casey Schauflere114e472008-02-04 22:29:50 -080097{
98 int rc;
Etienne Bassetecfcc532009-04-08 20:40:06 +020099 struct smk_audit_info ad;
100 char *sp, *tsp;
Casey Schauflere114e472008-02-04 22:29:50 -0800101
Ingo Molnar9e488582009-05-07 19:26:19 +1000102 rc = cap_ptrace_access_check(ctp, mode);
Casey Schauflere114e472008-02-04 22:29:50 -0800103 if (rc != 0)
104 return rc;
105
Etienne Bassetecfcc532009-04-08 20:40:06 +0200106 sp = current_security();
107 tsp = task_security(ctp);
108 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
109 smk_ad_setfield_u_tsk(&ad, ctp);
110
111 /* we won't log here, because rc can be overriden */
112 rc = smk_access(sp, tsp, MAY_READWRITE, NULL);
David Howells5cd9c582008-08-14 11:37:28 +0100113 if (rc != 0 && capable(CAP_MAC_OVERRIDE))
Etienne Bassetecfcc532009-04-08 20:40:06 +0200114 rc = 0;
115
116 smack_log(sp, tsp, MAY_READWRITE, rc, &ad);
David Howells5cd9c582008-08-14 11:37:28 +0100117 return rc;
118}
Casey Schauflere114e472008-02-04 22:29:50 -0800119
David Howells5cd9c582008-08-14 11:37:28 +0100120/**
121 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
122 * @ptp: parent task pointer
123 *
124 * Returns 0 if access is OK, an error code otherwise
125 *
126 * Do the capability checks, and require read and write.
127 */
128static int smack_ptrace_traceme(struct task_struct *ptp)
129{
130 int rc;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200131 struct smk_audit_info ad;
132 char *sp, *tsp;
David Howells5cd9c582008-08-14 11:37:28 +0100133
134 rc = cap_ptrace_traceme(ptp);
135 if (rc != 0)
136 return rc;
137
Etienne Bassetecfcc532009-04-08 20:40:06 +0200138 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
139 smk_ad_setfield_u_tsk(&ad, ptp);
140
141 sp = current_security();
142 tsp = task_security(ptp);
143 /* we won't log here, because rc can be overriden */
144 rc = smk_access(tsp, sp, MAY_READWRITE, NULL);
David Howells5cd9c582008-08-14 11:37:28 +0100145 if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE))
Etienne Bassetecfcc532009-04-08 20:40:06 +0200146 rc = 0;
147
148 smack_log(tsp, sp, MAY_READWRITE, rc, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800149 return rc;
150}
151
152/**
153 * smack_syslog - Smack approval on syslog
154 * @type: message type
155 *
156 * Require that the task has the floor label
157 *
158 * Returns 0 on success, error code otherwise.
159 */
Kees Cook00234592010-02-03 15:36:43 -0800160static int smack_syslog(int type, bool from_file)
Casey Schauflere114e472008-02-04 22:29:50 -0800161{
162 int rc;
David Howells86a264a2008-11-14 10:39:18 +1100163 char *sp = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -0800164
Kees Cook00234592010-02-03 15:36:43 -0800165 rc = cap_syslog(type, from_file);
Casey Schauflere114e472008-02-04 22:29:50 -0800166 if (rc != 0)
167 return rc;
168
169 if (capable(CAP_MAC_OVERRIDE))
170 return 0;
171
172 if (sp != smack_known_floor.smk_known)
173 rc = -EACCES;
174
175 return rc;
176}
177
178
179/*
180 * Superblock Hooks.
181 */
182
183/**
184 * smack_sb_alloc_security - allocate a superblock blob
185 * @sb: the superblock getting the blob
186 *
187 * Returns 0 on success or -ENOMEM on error.
188 */
189static int smack_sb_alloc_security(struct super_block *sb)
190{
191 struct superblock_smack *sbsp;
192
193 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
194
195 if (sbsp == NULL)
196 return -ENOMEM;
197
198 sbsp->smk_root = smack_known_floor.smk_known;
199 sbsp->smk_default = smack_known_floor.smk_known;
200 sbsp->smk_floor = smack_known_floor.smk_known;
201 sbsp->smk_hat = smack_known_hat.smk_known;
202 sbsp->smk_initialized = 0;
203 spin_lock_init(&sbsp->smk_sblock);
204
205 sb->s_security = sbsp;
206
207 return 0;
208}
209
210/**
211 * smack_sb_free_security - free a superblock blob
212 * @sb: the superblock getting the blob
213 *
214 */
215static void smack_sb_free_security(struct super_block *sb)
216{
217 kfree(sb->s_security);
218 sb->s_security = NULL;
219}
220
221/**
222 * smack_sb_copy_data - copy mount options data for processing
Casey Schauflere114e472008-02-04 22:29:50 -0800223 * @orig: where to start
Randy Dunlap251a2a92009-02-18 11:42:33 -0800224 * @smackopts: mount options string
Casey Schauflere114e472008-02-04 22:29:50 -0800225 *
226 * Returns 0 on success or -ENOMEM on error.
227 *
228 * Copy the Smack specific mount options out of the mount
229 * options list.
230 */
Eric Parise0007522008-03-05 10:31:54 -0500231static int smack_sb_copy_data(char *orig, char *smackopts)
Casey Schauflere114e472008-02-04 22:29:50 -0800232{
233 char *cp, *commap, *otheropts, *dp;
234
Casey Schauflere114e472008-02-04 22:29:50 -0800235 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
236 if (otheropts == NULL)
237 return -ENOMEM;
238
239 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
240 if (strstr(cp, SMK_FSDEFAULT) == cp)
241 dp = smackopts;
242 else if (strstr(cp, SMK_FSFLOOR) == cp)
243 dp = smackopts;
244 else if (strstr(cp, SMK_FSHAT) == cp)
245 dp = smackopts;
246 else if (strstr(cp, SMK_FSROOT) == cp)
247 dp = smackopts;
248 else
249 dp = otheropts;
250
251 commap = strchr(cp, ',');
252 if (commap != NULL)
253 *commap = '\0';
254
255 if (*dp != '\0')
256 strcat(dp, ",");
257 strcat(dp, cp);
258 }
259
260 strcpy(orig, otheropts);
261 free_page((unsigned long)otheropts);
262
263 return 0;
264}
265
266/**
267 * smack_sb_kern_mount - Smack specific mount processing
268 * @sb: the file system superblock
James Morris12204e22008-12-19 10:44:42 +1100269 * @flags: the mount flags
Casey Schauflere114e472008-02-04 22:29:50 -0800270 * @data: the smack mount options
271 *
272 * Returns 0 on success, an error code on failure
273 */
James Morris12204e22008-12-19 10:44:42 +1100274static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
Casey Schauflere114e472008-02-04 22:29:50 -0800275{
276 struct dentry *root = sb->s_root;
277 struct inode *inode = root->d_inode;
278 struct superblock_smack *sp = sb->s_security;
279 struct inode_smack *isp;
280 char *op;
281 char *commap;
282 char *nsp;
283
284 spin_lock(&sp->smk_sblock);
285 if (sp->smk_initialized != 0) {
286 spin_unlock(&sp->smk_sblock);
287 return 0;
288 }
289 sp->smk_initialized = 1;
290 spin_unlock(&sp->smk_sblock);
291
292 for (op = data; op != NULL; op = commap) {
293 commap = strchr(op, ',');
294 if (commap != NULL)
295 *commap++ = '\0';
296
297 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
298 op += strlen(SMK_FSHAT);
299 nsp = smk_import(op, 0);
300 if (nsp != NULL)
301 sp->smk_hat = nsp;
302 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
303 op += strlen(SMK_FSFLOOR);
304 nsp = smk_import(op, 0);
305 if (nsp != NULL)
306 sp->smk_floor = nsp;
307 } else if (strncmp(op, SMK_FSDEFAULT,
308 strlen(SMK_FSDEFAULT)) == 0) {
309 op += strlen(SMK_FSDEFAULT);
310 nsp = smk_import(op, 0);
311 if (nsp != NULL)
312 sp->smk_default = nsp;
313 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
314 op += strlen(SMK_FSROOT);
315 nsp = smk_import(op, 0);
316 if (nsp != NULL)
317 sp->smk_root = nsp;
318 }
319 }
320
321 /*
322 * Initialize the root inode.
323 */
324 isp = inode->i_security;
325 if (isp == NULL)
326 inode->i_security = new_inode_smack(sp->smk_root);
327 else
328 isp->smk_inode = sp->smk_root;
329
330 return 0;
331}
332
333/**
334 * smack_sb_statfs - Smack check on statfs
335 * @dentry: identifies the file system in question
336 *
337 * Returns 0 if current can read the floor of the filesystem,
338 * and error code otherwise
339 */
340static int smack_sb_statfs(struct dentry *dentry)
341{
342 struct superblock_smack *sbp = dentry->d_sb->s_security;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200343 int rc;
344 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800345
Etienne Bassetecfcc532009-04-08 20:40:06 +0200346 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
347 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
348
349 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
350 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -0800351}
352
353/**
354 * smack_sb_mount - Smack check for mounting
355 * @dev_name: unused
Randy Dunlap251a2a92009-02-18 11:42:33 -0800356 * @path: mount point
Casey Schauflere114e472008-02-04 22:29:50 -0800357 * @type: unused
358 * @flags: unused
359 * @data: unused
360 *
361 * Returns 0 if current can write the floor of the filesystem
362 * being mounted on, an error code otherwise.
363 */
Al Virob5266eb2008-03-22 17:48:24 -0400364static int smack_sb_mount(char *dev_name, struct path *path,
Casey Schauflere114e472008-02-04 22:29:50 -0800365 char *type, unsigned long flags, void *data)
366{
Al Virob5266eb2008-03-22 17:48:24 -0400367 struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200368 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800369
Etienne Bassetecfcc532009-04-08 20:40:06 +0200370 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
371 smk_ad_setfield_u_fs_path(&ad, *path);
372
373 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800374}
375
376/**
377 * smack_sb_umount - Smack check for unmounting
378 * @mnt: file system to unmount
379 * @flags: unused
380 *
381 * Returns 0 if current can write the floor of the filesystem
382 * being unmounted, an error code otherwise.
383 */
384static int smack_sb_umount(struct vfsmount *mnt, int flags)
385{
386 struct superblock_smack *sbp;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200387 struct smk_audit_info ad;
388
389 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
Al Virode27a5b2010-01-30 15:27:27 -0500390 smk_ad_setfield_u_fs_path_dentry(&ad, mnt->mnt_root);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200391 smk_ad_setfield_u_fs_path_mnt(&ad, mnt);
Casey Schauflere114e472008-02-04 22:29:50 -0800392
393 sbp = mnt->mnt_sb->s_security;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200394 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800395}
396
397/*
398 * Inode hooks
399 */
400
401/**
402 * smack_inode_alloc_security - allocate an inode blob
Randy Dunlap251a2a92009-02-18 11:42:33 -0800403 * @inode: the inode in need of a blob
Casey Schauflere114e472008-02-04 22:29:50 -0800404 *
405 * Returns 0 if it gets a blob, -ENOMEM otherwise
406 */
407static int smack_inode_alloc_security(struct inode *inode)
408{
David Howells86a264a2008-11-14 10:39:18 +1100409 inode->i_security = new_inode_smack(current_security());
Casey Schauflere114e472008-02-04 22:29:50 -0800410 if (inode->i_security == NULL)
411 return -ENOMEM;
412 return 0;
413}
414
415/**
416 * smack_inode_free_security - free an inode blob
Randy Dunlap251a2a92009-02-18 11:42:33 -0800417 * @inode: the inode with a blob
Casey Schauflere114e472008-02-04 22:29:50 -0800418 *
419 * Clears the blob pointer in inode
420 */
421static void smack_inode_free_security(struct inode *inode)
422{
423 kfree(inode->i_security);
424 inode->i_security = NULL;
425}
426
427/**
428 * smack_inode_init_security - copy out the smack from an inode
429 * @inode: the inode
430 * @dir: unused
431 * @name: where to put the attribute name
432 * @value: where to put the attribute value
433 * @len: where to put the length of the attribute
434 *
435 * Returns 0 if it all works out, -ENOMEM if there's no memory
436 */
437static int smack_inode_init_security(struct inode *inode, struct inode *dir,
438 char **name, void **value, size_t *len)
439{
440 char *isp = smk_of_inode(inode);
441
442 if (name) {
443 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
444 if (*name == NULL)
445 return -ENOMEM;
446 }
447
448 if (value) {
449 *value = kstrdup(isp, GFP_KERNEL);
450 if (*value == NULL)
451 return -ENOMEM;
452 }
453
454 if (len)
455 *len = strlen(isp) + 1;
456
457 return 0;
458}
459
460/**
461 * smack_inode_link - Smack check on link
462 * @old_dentry: the existing object
463 * @dir: unused
464 * @new_dentry: the new object
465 *
466 * Returns 0 if access is permitted, an error code otherwise
467 */
468static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
469 struct dentry *new_dentry)
470{
Casey Schauflere114e472008-02-04 22:29:50 -0800471 char *isp;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200472 struct smk_audit_info ad;
473 int rc;
474
475 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
476 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
Casey Schauflere114e472008-02-04 22:29:50 -0800477
478 isp = smk_of_inode(old_dentry->d_inode);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200479 rc = smk_curacc(isp, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800480
481 if (rc == 0 && new_dentry->d_inode != NULL) {
482 isp = smk_of_inode(new_dentry->d_inode);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200483 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
484 rc = smk_curacc(isp, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800485 }
486
487 return rc;
488}
489
490/**
491 * smack_inode_unlink - Smack check on inode deletion
492 * @dir: containing directory object
493 * @dentry: file to unlink
494 *
495 * Returns 0 if current can write the containing directory
496 * and the object, error code otherwise
497 */
498static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
499{
500 struct inode *ip = dentry->d_inode;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200501 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800502 int rc;
503
Etienne Bassetecfcc532009-04-08 20:40:06 +0200504 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
505 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
506
Casey Schauflere114e472008-02-04 22:29:50 -0800507 /*
508 * You need write access to the thing you're unlinking
509 */
Etienne Bassetecfcc532009-04-08 20:40:06 +0200510 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
511 if (rc == 0) {
Casey Schauflere114e472008-02-04 22:29:50 -0800512 /*
513 * You also need write access to the containing directory
514 */
Etienne Bassetecfcc532009-04-08 20:40:06 +0200515 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
516 smk_ad_setfield_u_fs_inode(&ad, dir);
517 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
518 }
Casey Schauflere114e472008-02-04 22:29:50 -0800519 return rc;
520}
521
522/**
523 * smack_inode_rmdir - Smack check on directory deletion
524 * @dir: containing directory object
525 * @dentry: directory to unlink
526 *
527 * Returns 0 if current can write the containing directory
528 * and the directory, error code otherwise
529 */
530static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
531{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200532 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800533 int rc;
534
Etienne Bassetecfcc532009-04-08 20:40:06 +0200535 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
536 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
537
Casey Schauflere114e472008-02-04 22:29:50 -0800538 /*
539 * You need write access to the thing you're removing
540 */
Etienne Bassetecfcc532009-04-08 20:40:06 +0200541 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
542 if (rc == 0) {
Casey Schauflere114e472008-02-04 22:29:50 -0800543 /*
544 * You also need write access to the containing directory
545 */
Etienne Bassetecfcc532009-04-08 20:40:06 +0200546 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
547 smk_ad_setfield_u_fs_inode(&ad, dir);
548 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
549 }
Casey Schauflere114e472008-02-04 22:29:50 -0800550
551 return rc;
552}
553
554/**
555 * smack_inode_rename - Smack check on rename
556 * @old_inode: the old directory
557 * @old_dentry: unused
558 * @new_inode: the new directory
559 * @new_dentry: unused
560 *
561 * Read and write access is required on both the old and
562 * new directories.
563 *
564 * Returns 0 if access is permitted, an error code otherwise
565 */
566static int smack_inode_rename(struct inode *old_inode,
567 struct dentry *old_dentry,
568 struct inode *new_inode,
569 struct dentry *new_dentry)
570{
571 int rc;
572 char *isp;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200573 struct smk_audit_info ad;
574
575 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
576 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
Casey Schauflere114e472008-02-04 22:29:50 -0800577
578 isp = smk_of_inode(old_dentry->d_inode);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200579 rc = smk_curacc(isp, MAY_READWRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800580
581 if (rc == 0 && new_dentry->d_inode != NULL) {
582 isp = smk_of_inode(new_dentry->d_inode);
Etienne Bassetecfcc532009-04-08 20:40:06 +0200583 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
584 rc = smk_curacc(isp, MAY_READWRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800585 }
Casey Schauflere114e472008-02-04 22:29:50 -0800586 return rc;
587}
588
589/**
590 * smack_inode_permission - Smack version of permission()
591 * @inode: the inode in question
592 * @mask: the access requested
Casey Schauflere114e472008-02-04 22:29:50 -0800593 *
594 * This is the important Smack hook.
595 *
596 * Returns 0 if access is permitted, -EACCES otherwise
597 */
Al Virob77b0642008-07-17 09:37:02 -0400598static int smack_inode_permission(struct inode *inode, int mask)
Casey Schauflere114e472008-02-04 22:29:50 -0800599{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200600 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800601 /*
602 * No permission to check. Existence test. Yup, it's there.
603 */
604 if (mask == 0)
605 return 0;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200606 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
607 smk_ad_setfield_u_fs_inode(&ad, inode);
608 return smk_curacc(smk_of_inode(inode), mask, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800609}
610
611/**
612 * smack_inode_setattr - Smack check for setting attributes
613 * @dentry: the object
614 * @iattr: for the force flag
615 *
616 * Returns 0 if access is permitted, an error code otherwise
617 */
618static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
619{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200620 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800621 /*
622 * Need to allow for clearing the setuid bit.
623 */
624 if (iattr->ia_valid & ATTR_FORCE)
625 return 0;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200626 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
627 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
Casey Schauflere114e472008-02-04 22:29:50 -0800628
Etienne Bassetecfcc532009-04-08 20:40:06 +0200629 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800630}
631
632/**
633 * smack_inode_getattr - Smack check for getting attributes
634 * @mnt: unused
635 * @dentry: the object
636 *
637 * Returns 0 if access is permitted, an error code otherwise
638 */
639static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
640{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200641 struct smk_audit_info ad;
642
643 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
644 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
645 smk_ad_setfield_u_fs_path_mnt(&ad, mnt);
646 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800647}
648
649/**
650 * smack_inode_setxattr - Smack check for setting xattrs
651 * @dentry: the object
652 * @name: name of the attribute
653 * @value: unused
654 * @size: unused
655 * @flags: unused
656 *
657 * This protects the Smack attribute explicitly.
658 *
659 * Returns 0 if access is permitted, an error code otherwise
660 */
David Howells8f0cfa52008-04-29 00:59:41 -0700661static int smack_inode_setxattr(struct dentry *dentry, const char *name,
662 const void *value, size_t size, int flags)
Casey Schauflere114e472008-02-04 22:29:50 -0800663{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200664 struct smk_audit_info ad;
Casey Schauflerbcdca222008-02-23 15:24:04 -0800665 int rc = 0;
Casey Schauflere114e472008-02-04 22:29:50 -0800666
Casey Schauflerbcdca222008-02-23 15:24:04 -0800667 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
668 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
669 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
670 if (!capable(CAP_MAC_ADMIN))
671 rc = -EPERM;
Etienne Bassetdefc4332009-04-16 23:58:42 +0200672 /*
673 * check label validity here so import wont fail on
674 * post_setxattr
675 */
676 if (size == 0 || size >= SMK_LABELLEN ||
677 smk_import(value, size) == NULL)
Etienne Basset43031542009-03-27 17:11:01 -0400678 rc = -EINVAL;
Casey Schauflerbcdca222008-02-23 15:24:04 -0800679 } else
680 rc = cap_inode_setxattr(dentry, name, value, size, flags);
681
Etienne Bassetecfcc532009-04-08 20:40:06 +0200682 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
683 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
684
Casey Schauflerbcdca222008-02-23 15:24:04 -0800685 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +0200686 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
Casey Schauflerbcdca222008-02-23 15:24:04 -0800687
688 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -0800689}
690
691/**
692 * smack_inode_post_setxattr - Apply the Smack update approved above
693 * @dentry: object
694 * @name: attribute name
695 * @value: attribute value
696 * @size: attribute size
697 * @flags: unused
698 *
699 * Set the pointer in the inode blob to the entry found
700 * in the master label list.
701 */
David Howells8f0cfa52008-04-29 00:59:41 -0700702static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
703 const void *value, size_t size, int flags)
Casey Schauflere114e472008-02-04 22:29:50 -0800704{
705 struct inode_smack *isp;
706 char *nsp;
707
708 /*
709 * Not SMACK
710 */
711 if (strcmp(name, XATTR_NAME_SMACK))
712 return;
713
Casey Schauflere114e472008-02-04 22:29:50 -0800714 isp = dentry->d_inode->i_security;
715
716 /*
717 * No locking is done here. This is a pointer
718 * assignment.
719 */
720 nsp = smk_import(value, size);
721 if (nsp != NULL)
722 isp->smk_inode = nsp;
723 else
724 isp->smk_inode = smack_known_invalid.smk_known;
725
726 return;
727}
728
729/*
730 * smack_inode_getxattr - Smack check on getxattr
731 * @dentry: the object
732 * @name: unused
733 *
734 * Returns 0 if access is permitted, an error code otherwise
735 */
David Howells8f0cfa52008-04-29 00:59:41 -0700736static int smack_inode_getxattr(struct dentry *dentry, const char *name)
Casey Schauflere114e472008-02-04 22:29:50 -0800737{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200738 struct smk_audit_info ad;
739
740 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
741 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
742
743 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800744}
745
746/*
747 * smack_inode_removexattr - Smack check on removexattr
748 * @dentry: the object
749 * @name: name of the attribute
750 *
751 * Removing the Smack attribute requires CAP_MAC_ADMIN
752 *
753 * Returns 0 if access is permitted, an error code otherwise
754 */
David Howells8f0cfa52008-04-29 00:59:41 -0700755static int smack_inode_removexattr(struct dentry *dentry, const char *name)
Casey Schauflere114e472008-02-04 22:29:50 -0800756{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200757 struct smk_audit_info ad;
Casey Schauflerbcdca222008-02-23 15:24:04 -0800758 int rc = 0;
Casey Schauflere114e472008-02-04 22:29:50 -0800759
Casey Schauflerbcdca222008-02-23 15:24:04 -0800760 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
761 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
762 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
763 if (!capable(CAP_MAC_ADMIN))
764 rc = -EPERM;
765 } else
766 rc = cap_inode_removexattr(dentry, name);
767
Etienne Bassetecfcc532009-04-08 20:40:06 +0200768 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
769 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
Casey Schauflerbcdca222008-02-23 15:24:04 -0800770 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +0200771 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
Casey Schauflerbcdca222008-02-23 15:24:04 -0800772
773 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -0800774}
775
776/**
777 * smack_inode_getsecurity - get smack xattrs
778 * @inode: the object
779 * @name: attribute name
780 * @buffer: where to put the result
Randy Dunlap251a2a92009-02-18 11:42:33 -0800781 * @alloc: unused
Casey Schauflere114e472008-02-04 22:29:50 -0800782 *
783 * Returns the size of the attribute or an error code
784 */
785static int smack_inode_getsecurity(const struct inode *inode,
786 const char *name, void **buffer,
787 bool alloc)
788{
789 struct socket_smack *ssp;
790 struct socket *sock;
791 struct super_block *sbp;
792 struct inode *ip = (struct inode *)inode;
793 char *isp;
794 int ilen;
795 int rc = 0;
796
797 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
798 isp = smk_of_inode(inode);
799 ilen = strlen(isp) + 1;
800 *buffer = isp;
801 return ilen;
802 }
803
804 /*
805 * The rest of the Smack xattrs are only on sockets.
806 */
807 sbp = ip->i_sb;
808 if (sbp->s_magic != SOCKFS_MAGIC)
809 return -EOPNOTSUPP;
810
811 sock = SOCKET_I(ip);
Ahmed S. Darwish2e1d1462008-02-13 15:03:34 -0800812 if (sock == NULL || sock->sk == NULL)
Casey Schauflere114e472008-02-04 22:29:50 -0800813 return -EOPNOTSUPP;
814
815 ssp = sock->sk->sk_security;
816
817 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
818 isp = ssp->smk_in;
819 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
820 isp = ssp->smk_out;
821 else
822 return -EOPNOTSUPP;
823
824 ilen = strlen(isp) + 1;
825 if (rc == 0) {
826 *buffer = isp;
827 rc = ilen;
828 }
829
830 return rc;
831}
832
833
834/**
835 * smack_inode_listsecurity - list the Smack attributes
836 * @inode: the object
837 * @buffer: where they go
838 * @buffer_size: size of buffer
839 *
840 * Returns 0 on success, -EINVAL otherwise
841 */
842static int smack_inode_listsecurity(struct inode *inode, char *buffer,
843 size_t buffer_size)
844{
845 int len = strlen(XATTR_NAME_SMACK);
846
847 if (buffer != NULL && len <= buffer_size) {
848 memcpy(buffer, XATTR_NAME_SMACK, len);
849 return len;
850 }
851 return -EINVAL;
852}
853
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +1000854/**
855 * smack_inode_getsecid - Extract inode's security id
856 * @inode: inode to extract the info from
857 * @secid: where result will be saved
858 */
859static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
860{
861 struct inode_smack *isp = inode->i_security;
862
863 *secid = smack_to_secid(isp->smk_inode);
864}
865
Casey Schauflere114e472008-02-04 22:29:50 -0800866/*
867 * File Hooks
868 */
869
870/**
871 * smack_file_permission - Smack check on file operations
872 * @file: unused
873 * @mask: unused
874 *
875 * Returns 0
876 *
877 * Should access checks be done on each read or write?
878 * UNICOS and SELinux say yes.
879 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
880 *
881 * I'll say no for now. Smack does not do the frequent
882 * label changing that SELinux does.
883 */
884static int smack_file_permission(struct file *file, int mask)
885{
886 return 0;
887}
888
889/**
890 * smack_file_alloc_security - assign a file security blob
891 * @file: the object
892 *
893 * The security blob for a file is a pointer to the master
894 * label list, so no allocation is done.
895 *
896 * Returns 0
897 */
898static int smack_file_alloc_security(struct file *file)
899{
David Howells86a264a2008-11-14 10:39:18 +1100900 file->f_security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -0800901 return 0;
902}
903
904/**
905 * smack_file_free_security - clear a file security blob
906 * @file: the object
907 *
908 * The security blob for a file is a pointer to the master
909 * label list, so no memory is freed.
910 */
911static void smack_file_free_security(struct file *file)
912{
913 file->f_security = NULL;
914}
915
916/**
917 * smack_file_ioctl - Smack check on ioctls
918 * @file: the object
919 * @cmd: what to do
920 * @arg: unused
921 *
922 * Relies heavily on the correct use of the ioctl command conventions.
923 *
924 * Returns 0 if allowed, error code otherwise
925 */
926static int smack_file_ioctl(struct file *file, unsigned int cmd,
927 unsigned long arg)
928{
929 int rc = 0;
Etienne Bassetecfcc532009-04-08 20:40:06 +0200930 struct smk_audit_info ad;
931
932 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
933 smk_ad_setfield_u_fs_path(&ad, file->f_path);
Casey Schauflere114e472008-02-04 22:29:50 -0800934
935 if (_IOC_DIR(cmd) & _IOC_WRITE)
Etienne Bassetecfcc532009-04-08 20:40:06 +0200936 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800937
938 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
Etienne Bassetecfcc532009-04-08 20:40:06 +0200939 rc = smk_curacc(file->f_security, MAY_READ, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800940
941 return rc;
942}
943
944/**
945 * smack_file_lock - Smack check on file locking
946 * @file: the object
Randy Dunlap251a2a92009-02-18 11:42:33 -0800947 * @cmd: unused
Casey Schauflere114e472008-02-04 22:29:50 -0800948 *
949 * Returns 0 if current has write access, error code otherwise
950 */
951static int smack_file_lock(struct file *file, unsigned int cmd)
952{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200953 struct smk_audit_info ad;
954
955 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
956 smk_ad_setfield_u_fs_path_dentry(&ad, file->f_path.dentry);
957 return smk_curacc(file->f_security, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800958}
959
960/**
961 * smack_file_fcntl - Smack check on fcntl
962 * @file: the object
963 * @cmd: what action to check
964 * @arg: unused
965 *
966 * Returns 0 if current has access, error code otherwise
967 */
968static int smack_file_fcntl(struct file *file, unsigned int cmd,
969 unsigned long arg)
970{
Etienne Bassetecfcc532009-04-08 20:40:06 +0200971 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -0800972 int rc;
973
Etienne Bassetecfcc532009-04-08 20:40:06 +0200974 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_FS);
975 smk_ad_setfield_u_fs_path(&ad, file->f_path);
976
Casey Schauflere114e472008-02-04 22:29:50 -0800977 switch (cmd) {
978 case F_DUPFD:
979 case F_GETFD:
980 case F_GETFL:
981 case F_GETLK:
982 case F_GETOWN:
983 case F_GETSIG:
Etienne Bassetecfcc532009-04-08 20:40:06 +0200984 rc = smk_curacc(file->f_security, MAY_READ, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800985 break;
986 case F_SETFD:
987 case F_SETFL:
988 case F_SETLK:
989 case F_SETLKW:
990 case F_SETOWN:
991 case F_SETSIG:
Etienne Bassetecfcc532009-04-08 20:40:06 +0200992 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800993 break;
994 default:
Etienne Bassetecfcc532009-04-08 20:40:06 +0200995 rc = smk_curacc(file->f_security, MAY_READWRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -0800996 }
997
998 return rc;
999}
1000
1001/**
1002 * smack_file_set_fowner - set the file security blob value
1003 * @file: object in question
1004 *
1005 * Returns 0
1006 * Further research may be required on this one.
1007 */
1008static int smack_file_set_fowner(struct file *file)
1009{
David Howells86a264a2008-11-14 10:39:18 +11001010 file->f_security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08001011 return 0;
1012}
1013
1014/**
1015 * smack_file_send_sigiotask - Smack on sigio
1016 * @tsk: The target task
1017 * @fown: the object the signal come from
1018 * @signum: unused
1019 *
1020 * Allow a privileged task to get signals even if it shouldn't
1021 *
1022 * Returns 0 if a subject with the object's smack could
1023 * write to the task, an error code otherwise.
1024 */
1025static int smack_file_send_sigiotask(struct task_struct *tsk,
1026 struct fown_struct *fown, int signum)
1027{
1028 struct file *file;
1029 int rc;
Etienne Bassetecfcc532009-04-08 20:40:06 +02001030 char *tsp = tsk->cred->security;
1031 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08001032
1033 /*
1034 * struct fown_struct is never outside the context of a struct file
1035 */
1036 file = container_of(fown, struct file, f_owner);
Etienne Bassetecfcc532009-04-08 20:40:06 +02001037 /* we don't log here as rc can be overriden */
1038 rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
David Howells5cd9c582008-08-14 11:37:28 +01001039 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
Etienne Bassetecfcc532009-04-08 20:40:06 +02001040 rc = 0;
1041
1042 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1043 smk_ad_setfield_u_tsk(&ad, tsk);
1044 smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08001045 return rc;
1046}
1047
1048/**
1049 * smack_file_receive - Smack file receive check
1050 * @file: the object
1051 *
1052 * Returns 0 if current has access, error code otherwise
1053 */
1054static int smack_file_receive(struct file *file)
1055{
1056 int may = 0;
Etienne Bassetecfcc532009-04-08 20:40:06 +02001057 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08001058
Etienne Bassetecfcc532009-04-08 20:40:06 +02001059 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1060 smk_ad_setfield_u_fs_path(&ad, file->f_path);
Casey Schauflere114e472008-02-04 22:29:50 -08001061 /*
1062 * This code relies on bitmasks.
1063 */
1064 if (file->f_mode & FMODE_READ)
1065 may = MAY_READ;
1066 if (file->f_mode & FMODE_WRITE)
1067 may |= MAY_WRITE;
1068
Etienne Bassetecfcc532009-04-08 20:40:06 +02001069 return smk_curacc(file->f_security, may, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08001070}
1071
1072/*
1073 * Task hooks
1074 */
1075
1076/**
David Howellsee18d642009-09-02 09:14:21 +01001077 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1078 * @new: the new credentials
1079 * @gfp: the atomicity of any memory allocations
1080 *
1081 * Prepare a blank set of credentials for modification. This must allocate all
1082 * the memory the LSM module might require such that cred_transfer() can
1083 * complete without error.
1084 */
1085static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1086{
1087 cred->security = NULL;
1088 return 0;
1089}
1090
1091
1092/**
David Howellsf1752ee2008-11-14 10:39:17 +11001093 * smack_cred_free - "free" task-level security credentials
1094 * @cred: the credentials in question
Casey Schauflere114e472008-02-04 22:29:50 -08001095 *
1096 * Smack isn't using copies of blobs. Everyone
1097 * points to an immutable list. The blobs never go away.
1098 * There is no leak here.
1099 */
David Howellsf1752ee2008-11-14 10:39:17 +11001100static void smack_cred_free(struct cred *cred)
Casey Schauflere114e472008-02-04 22:29:50 -08001101{
David Howellsf1752ee2008-11-14 10:39:17 +11001102 cred->security = NULL;
Casey Schauflere114e472008-02-04 22:29:50 -08001103}
1104
1105/**
David Howellsd84f4f92008-11-14 10:39:23 +11001106 * smack_cred_prepare - prepare new set of credentials for modification
1107 * @new: the new credentials
1108 * @old: the original credentials
1109 * @gfp: the atomicity of any memory allocations
1110 *
1111 * Prepare a new set of credentials for modification.
1112 */
1113static int smack_cred_prepare(struct cred *new, const struct cred *old,
1114 gfp_t gfp)
1115{
1116 new->security = old->security;
1117 return 0;
1118}
1119
Randy Dunlap251a2a92009-02-18 11:42:33 -08001120/**
David Howellsee18d642009-09-02 09:14:21 +01001121 * smack_cred_transfer - Transfer the old credentials to the new credentials
1122 * @new: the new credentials
1123 * @old: the original credentials
1124 *
1125 * Fill in a set of blank credentials from another set of credentials.
1126 */
1127static void smack_cred_transfer(struct cred *new, const struct cred *old)
1128{
1129 new->security = old->security;
1130}
1131
1132/**
David Howells3a3b7ce2008-11-14 10:39:28 +11001133 * smack_kernel_act_as - Set the subjective context in a set of credentials
Randy Dunlap251a2a92009-02-18 11:42:33 -08001134 * @new: points to the set of credentials to be modified.
1135 * @secid: specifies the security ID to be set
David Howells3a3b7ce2008-11-14 10:39:28 +11001136 *
1137 * Set the security data for a kernel service.
1138 */
1139static int smack_kernel_act_as(struct cred *new, u32 secid)
1140{
1141 char *smack = smack_from_secid(secid);
1142
1143 if (smack == NULL)
1144 return -EINVAL;
1145
1146 new->security = smack;
1147 return 0;
1148}
1149
1150/**
1151 * smack_kernel_create_files_as - Set the file creation label in a set of creds
Randy Dunlap251a2a92009-02-18 11:42:33 -08001152 * @new: points to the set of credentials to be modified
1153 * @inode: points to the inode to use as a reference
David Howells3a3b7ce2008-11-14 10:39:28 +11001154 *
1155 * Set the file creation context in a set of credentials to the same
1156 * as the objective context of the specified inode
1157 */
1158static int smack_kernel_create_files_as(struct cred *new,
1159 struct inode *inode)
1160{
1161 struct inode_smack *isp = inode->i_security;
1162
1163 new->security = isp->smk_inode;
1164 return 0;
1165}
1166
1167/**
Etienne Bassetecfcc532009-04-08 20:40:06 +02001168 * smk_curacc_on_task - helper to log task related access
1169 * @p: the task object
1170 * @access : the access requested
1171 *
1172 * Return 0 if access is permitted
1173 */
1174static int smk_curacc_on_task(struct task_struct *p, int access)
1175{
1176 struct smk_audit_info ad;
1177
1178 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1179 smk_ad_setfield_u_tsk(&ad, p);
1180 return smk_curacc(task_security(p), access, &ad);
1181}
1182
1183/**
Casey Schauflere114e472008-02-04 22:29:50 -08001184 * smack_task_setpgid - Smack check on setting pgid
1185 * @p: the task object
1186 * @pgid: unused
1187 *
1188 * Return 0 if write access is permitted
1189 */
1190static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1191{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001192 return smk_curacc_on_task(p, MAY_WRITE);
Casey Schauflere114e472008-02-04 22:29:50 -08001193}
1194
1195/**
1196 * smack_task_getpgid - Smack access check for getpgid
1197 * @p: the object task
1198 *
1199 * Returns 0 if current can read the object task, error code otherwise
1200 */
1201static int smack_task_getpgid(struct task_struct *p)
1202{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001203 return smk_curacc_on_task(p, MAY_READ);
Casey Schauflere114e472008-02-04 22:29:50 -08001204}
1205
1206/**
1207 * smack_task_getsid - Smack access check for getsid
1208 * @p: the object task
1209 *
1210 * Returns 0 if current can read the object task, error code otherwise
1211 */
1212static int smack_task_getsid(struct task_struct *p)
1213{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001214 return smk_curacc_on_task(p, MAY_READ);
Casey Schauflere114e472008-02-04 22:29:50 -08001215}
1216
1217/**
1218 * smack_task_getsecid - get the secid of the task
1219 * @p: the object task
1220 * @secid: where to put the result
1221 *
1222 * Sets the secid to contain a u32 version of the smack label.
1223 */
1224static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1225{
David Howellsc69e8d92008-11-14 10:39:19 +11001226 *secid = smack_to_secid(task_security(p));
Casey Schauflere114e472008-02-04 22:29:50 -08001227}
1228
1229/**
1230 * smack_task_setnice - Smack check on setting nice
1231 * @p: the task object
1232 * @nice: unused
1233 *
1234 * Return 0 if write access is permitted
1235 */
1236static int smack_task_setnice(struct task_struct *p, int nice)
1237{
Casey Schauflerbcdca222008-02-23 15:24:04 -08001238 int rc;
1239
1240 rc = cap_task_setnice(p, nice);
1241 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +02001242 rc = smk_curacc_on_task(p, MAY_WRITE);
Casey Schauflerbcdca222008-02-23 15:24:04 -08001243 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -08001244}
1245
1246/**
1247 * smack_task_setioprio - Smack check on setting ioprio
1248 * @p: the task object
1249 * @ioprio: unused
1250 *
1251 * Return 0 if write access is permitted
1252 */
1253static int smack_task_setioprio(struct task_struct *p, int ioprio)
1254{
Casey Schauflerbcdca222008-02-23 15:24:04 -08001255 int rc;
1256
1257 rc = cap_task_setioprio(p, ioprio);
1258 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +02001259 rc = smk_curacc_on_task(p, MAY_WRITE);
Casey Schauflerbcdca222008-02-23 15:24:04 -08001260 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -08001261}
1262
1263/**
1264 * smack_task_getioprio - Smack check on reading ioprio
1265 * @p: the task object
1266 *
1267 * Return 0 if read access is permitted
1268 */
1269static int smack_task_getioprio(struct task_struct *p)
1270{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001271 return smk_curacc_on_task(p, MAY_READ);
Casey Schauflere114e472008-02-04 22:29:50 -08001272}
1273
1274/**
1275 * smack_task_setscheduler - Smack check on setting scheduler
1276 * @p: the task object
1277 * @policy: unused
1278 * @lp: unused
1279 *
1280 * Return 0 if read access is permitted
1281 */
1282static int smack_task_setscheduler(struct task_struct *p, int policy,
1283 struct sched_param *lp)
1284{
Casey Schauflerbcdca222008-02-23 15:24:04 -08001285 int rc;
1286
1287 rc = cap_task_setscheduler(p, policy, lp);
1288 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +02001289 rc = smk_curacc_on_task(p, MAY_WRITE);
Casey Schauflerbcdca222008-02-23 15:24:04 -08001290 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -08001291}
1292
1293/**
1294 * smack_task_getscheduler - Smack check on reading scheduler
1295 * @p: the task object
1296 *
1297 * Return 0 if read access is permitted
1298 */
1299static int smack_task_getscheduler(struct task_struct *p)
1300{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001301 return smk_curacc_on_task(p, MAY_READ);
Casey Schauflere114e472008-02-04 22:29:50 -08001302}
1303
1304/**
1305 * smack_task_movememory - Smack check on moving memory
1306 * @p: the task object
1307 *
1308 * Return 0 if write access is permitted
1309 */
1310static int smack_task_movememory(struct task_struct *p)
1311{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001312 return smk_curacc_on_task(p, MAY_WRITE);
Casey Schauflere114e472008-02-04 22:29:50 -08001313}
1314
1315/**
1316 * smack_task_kill - Smack check on signal delivery
1317 * @p: the task object
1318 * @info: unused
1319 * @sig: unused
1320 * @secid: identifies the smack to use in lieu of current's
1321 *
1322 * Return 0 if write access is permitted
1323 *
1324 * The secid behavior is an artifact of an SELinux hack
1325 * in the USB code. Someday it may go away.
1326 */
1327static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1328 int sig, u32 secid)
1329{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001330 struct smk_audit_info ad;
1331
1332 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1333 smk_ad_setfield_u_tsk(&ad, p);
Casey Schauflere114e472008-02-04 22:29:50 -08001334 /*
Casey Schauflere114e472008-02-04 22:29:50 -08001335 * Sending a signal requires that the sender
1336 * can write the receiver.
1337 */
1338 if (secid == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +02001339 return smk_curacc(task_security(p), MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08001340 /*
1341 * If the secid isn't 0 we're dealing with some USB IO
1342 * specific behavior. This is not clean. For one thing
1343 * we can't take privilege into account.
1344 */
Etienne Bassetecfcc532009-04-08 20:40:06 +02001345 return smk_access(smack_from_secid(secid), task_security(p),
1346 MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08001347}
1348
1349/**
1350 * smack_task_wait - Smack access check for waiting
1351 * @p: task to wait for
1352 *
1353 * Returns 0 if current can wait for p, error code otherwise
1354 */
1355static int smack_task_wait(struct task_struct *p)
1356{
Etienne Bassetecfcc532009-04-08 20:40:06 +02001357 struct smk_audit_info ad;
1358 char *sp = current_security();
1359 char *tsp = task_security(p);
Casey Schauflere114e472008-02-04 22:29:50 -08001360 int rc;
1361
Etienne Bassetecfcc532009-04-08 20:40:06 +02001362 /* we don't log here, we can be overriden */
1363 rc = smk_access(sp, tsp, MAY_WRITE, NULL);
Casey Schauflere114e472008-02-04 22:29:50 -08001364 if (rc == 0)
Etienne Bassetecfcc532009-04-08 20:40:06 +02001365 goto out_log;
Casey Schauflere114e472008-02-04 22:29:50 -08001366
1367 /*
1368 * Allow the operation to succeed if either task
1369 * has privilege to perform operations that might
1370 * account for the smack labels having gotten to
1371 * be different in the first place.
1372 *
David Howells5cd9c582008-08-14 11:37:28 +01001373 * This breaks the strict subject/object access
Casey Schauflere114e472008-02-04 22:29:50 -08001374 * control ideal, taking the object's privilege
1375 * state into account in the decision as well as
1376 * the smack value.
1377 */
David Howells5cd9c582008-08-14 11:37:28 +01001378 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
Etienne Bassetecfcc532009-04-08 20:40:06 +02001379 rc = 0;
1380 /* we log only if we didn't get overriden */
1381 out_log:
1382 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1383 smk_ad_setfield_u_tsk(&ad, p);
1384 smack_log(sp, tsp, MAY_WRITE, rc, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08001385 return rc;
1386}
1387
1388/**
1389 * smack_task_to_inode - copy task smack into the inode blob
1390 * @p: task to copy from
Randy Dunlap251a2a92009-02-18 11:42:33 -08001391 * @inode: inode to copy to
Casey Schauflere114e472008-02-04 22:29:50 -08001392 *
1393 * Sets the smack pointer in the inode security blob
1394 */
1395static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1396{
1397 struct inode_smack *isp = inode->i_security;
David Howellsc69e8d92008-11-14 10:39:19 +11001398 isp->smk_inode = task_security(p);
Casey Schauflere114e472008-02-04 22:29:50 -08001399}
1400
1401/*
1402 * Socket hooks.
1403 */
1404
1405/**
1406 * smack_sk_alloc_security - Allocate a socket blob
1407 * @sk: the socket
1408 * @family: unused
Randy Dunlap251a2a92009-02-18 11:42:33 -08001409 * @gfp_flags: memory allocation flags
Casey Schauflere114e472008-02-04 22:29:50 -08001410 *
1411 * Assign Smack pointers to current
1412 *
1413 * Returns 0 on success, -ENOMEM is there's no memory
1414 */
1415static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1416{
David Howells86a264a2008-11-14 10:39:18 +11001417 char *csp = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08001418 struct socket_smack *ssp;
1419
1420 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1421 if (ssp == NULL)
1422 return -ENOMEM;
1423
1424 ssp->smk_in = csp;
1425 ssp->smk_out = csp;
1426 ssp->smk_packet[0] = '\0';
1427
1428 sk->sk_security = ssp;
1429
1430 return 0;
1431}
1432
1433/**
1434 * smack_sk_free_security - Free a socket blob
1435 * @sk: the socket
1436 *
1437 * Clears the blob pointer
1438 */
1439static void smack_sk_free_security(struct sock *sk)
1440{
1441 kfree(sk->sk_security);
1442}
1443
1444/**
Paul Moore07feee82009-03-27 17:10:54 -04001445* smack_host_label - check host based restrictions
1446* @sip: the object end
1447*
1448* looks for host based access restrictions
1449*
1450* This version will only be appropriate for really small sets of single label
1451* hosts. The caller is responsible for ensuring that the RCU read lock is
1452* taken before calling this function.
1453*
1454* Returns the label of the far end or NULL if it's not special.
1455*/
1456static char *smack_host_label(struct sockaddr_in *sip)
1457{
1458 struct smk_netlbladdr *snp;
1459 struct in_addr *siap = &sip->sin_addr;
1460
1461 if (siap->s_addr == 0)
1462 return NULL;
1463
1464 list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list)
1465 /*
1466 * we break after finding the first match because
1467 * the list is sorted from longest to shortest mask
1468 * so we have found the most specific match
1469 */
1470 if ((&snp->smk_host.sin_addr)->s_addr ==
Etienne Basset43031542009-03-27 17:11:01 -04001471 (siap->s_addr & (&snp->smk_mask)->s_addr)) {
1472 /* we have found the special CIPSO option */
1473 if (snp->smk_label == smack_cipso_option)
1474 return NULL;
Paul Moore07feee82009-03-27 17:10:54 -04001475 return snp->smk_label;
Etienne Basset43031542009-03-27 17:11:01 -04001476 }
Paul Moore07feee82009-03-27 17:10:54 -04001477
1478 return NULL;
1479}
1480
1481/**
Casey Schauflere114e472008-02-04 22:29:50 -08001482 * smack_set_catset - convert a capset to netlabel mls categories
1483 * @catset: the Smack categories
1484 * @sap: where to put the netlabel categories
1485 *
1486 * Allocates and fills attr.mls.cat
1487 */
1488static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1489{
1490 unsigned char *cp;
1491 unsigned char m;
1492 int cat;
1493 int rc;
1494 int byte;
1495
Harvey Harrisonc60264c2008-04-28 02:13:41 -07001496 if (!catset)
Casey Schauflere114e472008-02-04 22:29:50 -08001497 return;
1498
1499 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1500 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1501 sap->attr.mls.cat->startbit = 0;
1502
1503 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1504 for (m = 0x80; m != 0; m >>= 1, cat++) {
1505 if ((m & *cp) == 0)
1506 continue;
1507 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1508 cat, GFP_ATOMIC);
1509 }
1510}
1511
1512/**
1513 * smack_to_secattr - fill a secattr from a smack value
1514 * @smack: the smack value
1515 * @nlsp: where the result goes
1516 *
1517 * Casey says that CIPSO is good enough for now.
1518 * It can be used to effect.
1519 * It can also be abused to effect when necessary.
1520 * Appologies to the TSIG group in general and GW in particular.
1521 */
1522static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1523{
1524 struct smack_cipso cipso;
1525 int rc;
1526
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001527 nlsp->domain = smack;
1528 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
Casey Schauflere114e472008-02-04 22:29:50 -08001529
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001530 rc = smack_to_cipso(smack, &cipso);
1531 if (rc == 0) {
1532 nlsp->attr.mls.lvl = cipso.smk_level;
1533 smack_set_catset(cipso.smk_catset, nlsp);
1534 } else {
1535 nlsp->attr.mls.lvl = smack_cipso_direct;
1536 smack_set_catset(smack, nlsp);
Casey Schauflere114e472008-02-04 22:29:50 -08001537 }
1538}
1539
1540/**
1541 * smack_netlabel - Set the secattr on a socket
1542 * @sk: the socket
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001543 * @labeled: socket label scheme
Casey Schauflere114e472008-02-04 22:29:50 -08001544 *
1545 * Convert the outbound smack value (smk_out) to a
1546 * secattr and attach it to the socket.
1547 *
1548 * Returns 0 on success or an error code
1549 */
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001550static int smack_netlabel(struct sock *sk, int labeled)
Casey Schauflere114e472008-02-04 22:29:50 -08001551{
Paul Moore07feee82009-03-27 17:10:54 -04001552 struct socket_smack *ssp = sk->sk_security;
Casey Schauflere114e472008-02-04 22:29:50 -08001553 struct netlbl_lsm_secattr secattr;
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001554 int rc = 0;
Casey Schauflere114e472008-02-04 22:29:50 -08001555
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001556 /*
1557 * Usually the netlabel code will handle changing the
1558 * packet labeling based on the label.
1559 * The case of a single label host is different, because
1560 * a single label host should never get a labeled packet
1561 * even though the label is usually associated with a packet
1562 * label.
1563 */
1564 local_bh_disable();
1565 bh_lock_sock_nested(sk);
1566
1567 if (ssp->smk_out == smack_net_ambient ||
1568 labeled == SMACK_UNLABELED_SOCKET)
1569 netlbl_sock_delattr(sk);
1570 else {
1571 netlbl_secattr_init(&secattr);
1572 smack_to_secattr(ssp->smk_out, &secattr);
Paul Moore389fb802009-03-27 17:10:34 -04001573 rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001574 netlbl_secattr_destroy(&secattr);
1575 }
1576
1577 bh_unlock_sock(sk);
1578 local_bh_enable();
Casey Schaufler4bc87e62008-02-15 15:24:25 -08001579
Casey Schauflere114e472008-02-04 22:29:50 -08001580 return rc;
1581}
1582
1583/**
Paul Moore07feee82009-03-27 17:10:54 -04001584 * smack_netlbel_send - Set the secattr on a socket and perform access checks
1585 * @sk: the socket
1586 * @sap: the destination address
1587 *
1588 * Set the correct secattr for the given socket based on the destination
1589 * address and perform any outbound access checks needed.
1590 *
1591 * Returns 0 on success or an error code.
1592 *
1593 */
1594static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
1595{
1596 int rc;
1597 int sk_lbl;
1598 char *hostsp;
1599 struct socket_smack *ssp = sk->sk_security;
Etienne Bassetecfcc532009-04-08 20:40:06 +02001600 struct smk_audit_info ad;
Paul Moore07feee82009-03-27 17:10:54 -04001601
1602 rcu_read_lock();
1603 hostsp = smack_host_label(sap);
1604 if (hostsp != NULL) {
1605 sk_lbl = SMACK_UNLABELED_SOCKET;
Etienne Bassetecfcc532009-04-08 20:40:06 +02001606#ifdef CONFIG_AUDIT
1607 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
1608 ad.a.u.net.family = sap->sin_family;
1609 ad.a.u.net.dport = sap->sin_port;
1610 ad.a.u.net.v4info.daddr = sap->sin_addr.s_addr;
1611#endif
1612 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
Paul Moore07feee82009-03-27 17:10:54 -04001613 } else {
1614 sk_lbl = SMACK_CIPSO_SOCKET;
1615 rc = 0;
1616 }
1617 rcu_read_unlock();
1618 if (rc != 0)
1619 return rc;
1620
1621 return smack_netlabel(sk, sk_lbl);
1622}
1623
1624/**
Casey Schauflere114e472008-02-04 22:29:50 -08001625 * smack_inode_setsecurity - set smack xattrs
1626 * @inode: the object
1627 * @name: attribute name
1628 * @value: attribute value
1629 * @size: size of the attribute
1630 * @flags: unused
1631 *
1632 * Sets the named attribute in the appropriate blob
1633 *
1634 * Returns 0 on success, or an error code
1635 */
1636static int smack_inode_setsecurity(struct inode *inode, const char *name,
1637 const void *value, size_t size, int flags)
1638{
1639 char *sp;
1640 struct inode_smack *nsp = inode->i_security;
1641 struct socket_smack *ssp;
1642 struct socket *sock;
Casey Schaufler4bc87e62008-02-15 15:24:25 -08001643 int rc = 0;
Casey Schauflere114e472008-02-04 22:29:50 -08001644
Etienne Basset43031542009-03-27 17:11:01 -04001645 if (value == NULL || size > SMK_LABELLEN || size == 0)
Casey Schauflere114e472008-02-04 22:29:50 -08001646 return -EACCES;
1647
1648 sp = smk_import(value, size);
1649 if (sp == NULL)
1650 return -EINVAL;
1651
1652 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1653 nsp->smk_inode = sp;
David P. Quigleyddd29ec2009-09-09 14:25:37 -04001654 nsp->smk_flags |= SMK_INODE_INSTANT;
Casey Schauflere114e472008-02-04 22:29:50 -08001655 return 0;
1656 }
1657 /*
1658 * The rest of the Smack xattrs are only on sockets.
1659 */
1660 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1661 return -EOPNOTSUPP;
1662
1663 sock = SOCKET_I(inode);
Ahmed S. Darwish2e1d1462008-02-13 15:03:34 -08001664 if (sock == NULL || sock->sk == NULL)
Casey Schauflere114e472008-02-04 22:29:50 -08001665 return -EOPNOTSUPP;
1666
1667 ssp = sock->sk->sk_security;
1668
1669 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1670 ssp->smk_in = sp;
1671 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1672 ssp->smk_out = sp;
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001673 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
Casey Schaufler4bc87e62008-02-15 15:24:25 -08001674 if (rc != 0)
1675 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
1676 __func__, -rc);
Casey Schauflere114e472008-02-04 22:29:50 -08001677 } else
1678 return -EOPNOTSUPP;
1679
1680 return 0;
1681}
1682
1683/**
1684 * smack_socket_post_create - finish socket setup
1685 * @sock: the socket
1686 * @family: protocol family
1687 * @type: unused
1688 * @protocol: unused
1689 * @kern: unused
1690 *
1691 * Sets the netlabel information on the socket
1692 *
1693 * Returns 0 on success, and error code otherwise
1694 */
1695static int smack_socket_post_create(struct socket *sock, int family,
1696 int type, int protocol, int kern)
1697{
Ahmed S. Darwish2e1d1462008-02-13 15:03:34 -08001698 if (family != PF_INET || sock->sk == NULL)
Casey Schauflere114e472008-02-04 22:29:50 -08001699 return 0;
1700 /*
1701 * Set the outbound netlbl.
1702 */
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001703 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
1704}
1705
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001706/**
1707 * smack_socket_connect - connect access check
1708 * @sock: the socket
1709 * @sap: the other end
1710 * @addrlen: size of sap
1711 *
1712 * Verifies that a connection may be possible
1713 *
1714 * Returns 0 on success, and error code otherwise
1715 */
1716static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
1717 int addrlen)
1718{
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001719 if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
1720 return 0;
Casey Schaufler6d3dc072008-12-31 12:54:12 -05001721 if (addrlen < sizeof(struct sockaddr_in))
1722 return -EINVAL;
1723
Paul Moore07feee82009-03-27 17:10:54 -04001724 return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
Casey Schauflere114e472008-02-04 22:29:50 -08001725}
1726
1727/**
1728 * smack_flags_to_may - convert S_ to MAY_ values
1729 * @flags: the S_ value
1730 *
1731 * Returns the equivalent MAY_ value
1732 */
1733static int smack_flags_to_may(int flags)
1734{
1735 int may = 0;
1736
1737 if (flags & S_IRUGO)
1738 may |= MAY_READ;
1739 if (flags & S_IWUGO)
1740 may |= MAY_WRITE;
1741 if (flags & S_IXUGO)
1742 may |= MAY_EXEC;
1743
1744 return may;
1745}
1746
1747/**
1748 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
1749 * @msg: the object
1750 *
1751 * Returns 0
1752 */
1753static int smack_msg_msg_alloc_security(struct msg_msg *msg)
1754{
David Howells86a264a2008-11-14 10:39:18 +11001755 msg->security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08001756 return 0;
1757}
1758
1759/**
1760 * smack_msg_msg_free_security - Clear the security blob for msg_msg
1761 * @msg: the object
1762 *
1763 * Clears the blob pointer
1764 */
1765static void smack_msg_msg_free_security(struct msg_msg *msg)
1766{
1767 msg->security = NULL;
1768}
1769
1770/**
1771 * smack_of_shm - the smack pointer for the shm
1772 * @shp: the object
1773 *
1774 * Returns a pointer to the smack value
1775 */
1776static char *smack_of_shm(struct shmid_kernel *shp)
1777{
1778 return (char *)shp->shm_perm.security;
1779}
1780
1781/**
1782 * smack_shm_alloc_security - Set the security blob for shm
1783 * @shp: the object
1784 *
1785 * Returns 0
1786 */
1787static int smack_shm_alloc_security(struct shmid_kernel *shp)
1788{
1789 struct kern_ipc_perm *isp = &shp->shm_perm;
1790
David Howells86a264a2008-11-14 10:39:18 +11001791 isp->security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08001792 return 0;
1793}
1794
1795/**
1796 * smack_shm_free_security - Clear the security blob for shm
1797 * @shp: the object
1798 *
1799 * Clears the blob pointer
1800 */
1801static void smack_shm_free_security(struct shmid_kernel *shp)
1802{
1803 struct kern_ipc_perm *isp = &shp->shm_perm;
1804
1805 isp->security = NULL;
1806}
1807
1808/**
Etienne Bassetecfcc532009-04-08 20:40:06 +02001809 * smk_curacc_shm : check if current has access on shm
1810 * @shp : the object
1811 * @access : access requested
1812 *
1813 * Returns 0 if current has the requested access, error code otherwise
1814 */
1815static int smk_curacc_shm(struct shmid_kernel *shp, int access)
1816{
1817 char *ssp = smack_of_shm(shp);
1818 struct smk_audit_info ad;
1819
1820#ifdef CONFIG_AUDIT
1821 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
1822 ad.a.u.ipc_id = shp->shm_perm.id;
1823#endif
1824 return smk_curacc(ssp, access, &ad);
1825}
1826
1827/**
Casey Schauflere114e472008-02-04 22:29:50 -08001828 * smack_shm_associate - Smack access check for shm
1829 * @shp: the object
1830 * @shmflg: access requested
1831 *
1832 * Returns 0 if current has the requested access, error code otherwise
1833 */
1834static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
1835{
Casey Schauflere114e472008-02-04 22:29:50 -08001836 int may;
1837
1838 may = smack_flags_to_may(shmflg);
Etienne Bassetecfcc532009-04-08 20:40:06 +02001839 return smk_curacc_shm(shp, may);
Casey Schauflere114e472008-02-04 22:29:50 -08001840}
1841
1842/**
1843 * smack_shm_shmctl - Smack access check for shm
1844 * @shp: the object
1845 * @cmd: what it wants to do
1846 *
1847 * Returns 0 if current has the requested access, error code otherwise
1848 */
1849static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
1850{
Casey Schauflere114e472008-02-04 22:29:50 -08001851 int may;
1852
1853 switch (cmd) {
1854 case IPC_STAT:
1855 case SHM_STAT:
1856 may = MAY_READ;
1857 break;
1858 case IPC_SET:
1859 case SHM_LOCK:
1860 case SHM_UNLOCK:
1861 case IPC_RMID:
1862 may = MAY_READWRITE;
1863 break;
1864 case IPC_INFO:
1865 case SHM_INFO:
1866 /*
1867 * System level information.
1868 */
1869 return 0;
1870 default:
1871 return -EINVAL;
1872 }
Etienne Bassetecfcc532009-04-08 20:40:06 +02001873 return smk_curacc_shm(shp, may);
Casey Schauflere114e472008-02-04 22:29:50 -08001874}
1875
1876/**
1877 * smack_shm_shmat - Smack access for shmat
1878 * @shp: the object
1879 * @shmaddr: unused
1880 * @shmflg: access requested
1881 *
1882 * Returns 0 if current has the requested access, error code otherwise
1883 */
1884static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
1885 int shmflg)
1886{
Casey Schauflere114e472008-02-04 22:29:50 -08001887 int may;
1888
1889 may = smack_flags_to_may(shmflg);
Etienne Bassetecfcc532009-04-08 20:40:06 +02001890 return smk_curacc_shm(shp, may);
Casey Schauflere114e472008-02-04 22:29:50 -08001891}
1892
1893/**
1894 * smack_of_sem - the smack pointer for the sem
1895 * @sma: the object
1896 *
1897 * Returns a pointer to the smack value
1898 */
1899static char *smack_of_sem(struct sem_array *sma)
1900{
1901 return (char *)sma->sem_perm.security;
1902}
1903
1904/**
1905 * smack_sem_alloc_security - Set the security blob for sem
1906 * @sma: the object
1907 *
1908 * Returns 0
1909 */
1910static int smack_sem_alloc_security(struct sem_array *sma)
1911{
1912 struct kern_ipc_perm *isp = &sma->sem_perm;
1913
David Howells86a264a2008-11-14 10:39:18 +11001914 isp->security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08001915 return 0;
1916}
1917
1918/**
1919 * smack_sem_free_security - Clear the security blob for sem
1920 * @sma: the object
1921 *
1922 * Clears the blob pointer
1923 */
1924static void smack_sem_free_security(struct sem_array *sma)
1925{
1926 struct kern_ipc_perm *isp = &sma->sem_perm;
1927
1928 isp->security = NULL;
1929}
1930
1931/**
Etienne Bassetecfcc532009-04-08 20:40:06 +02001932 * smk_curacc_sem : check if current has access on sem
1933 * @sma : the object
1934 * @access : access requested
1935 *
1936 * Returns 0 if current has the requested access, error code otherwise
1937 */
1938static int smk_curacc_sem(struct sem_array *sma, int access)
1939{
1940 char *ssp = smack_of_sem(sma);
1941 struct smk_audit_info ad;
1942
1943#ifdef CONFIG_AUDIT
1944 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
1945 ad.a.u.ipc_id = sma->sem_perm.id;
1946#endif
1947 return smk_curacc(ssp, access, &ad);
1948}
1949
1950/**
Casey Schauflere114e472008-02-04 22:29:50 -08001951 * smack_sem_associate - Smack access check for sem
1952 * @sma: the object
1953 * @semflg: access requested
1954 *
1955 * Returns 0 if current has the requested access, error code otherwise
1956 */
1957static int smack_sem_associate(struct sem_array *sma, int semflg)
1958{
Casey Schauflere114e472008-02-04 22:29:50 -08001959 int may;
1960
1961 may = smack_flags_to_may(semflg);
Etienne Bassetecfcc532009-04-08 20:40:06 +02001962 return smk_curacc_sem(sma, may);
Casey Schauflere114e472008-02-04 22:29:50 -08001963}
1964
1965/**
1966 * smack_sem_shmctl - Smack access check for sem
1967 * @sma: the object
1968 * @cmd: what it wants to do
1969 *
1970 * Returns 0 if current has the requested access, error code otherwise
1971 */
1972static int smack_sem_semctl(struct sem_array *sma, int cmd)
1973{
Casey Schauflere114e472008-02-04 22:29:50 -08001974 int may;
1975
1976 switch (cmd) {
1977 case GETPID:
1978 case GETNCNT:
1979 case GETZCNT:
1980 case GETVAL:
1981 case GETALL:
1982 case IPC_STAT:
1983 case SEM_STAT:
1984 may = MAY_READ;
1985 break;
1986 case SETVAL:
1987 case SETALL:
1988 case IPC_RMID:
1989 case IPC_SET:
1990 may = MAY_READWRITE;
1991 break;
1992 case IPC_INFO:
1993 case SEM_INFO:
1994 /*
1995 * System level information
1996 */
1997 return 0;
1998 default:
1999 return -EINVAL;
2000 }
2001
Etienne Bassetecfcc532009-04-08 20:40:06 +02002002 return smk_curacc_sem(sma, may);
Casey Schauflere114e472008-02-04 22:29:50 -08002003}
2004
2005/**
2006 * smack_sem_semop - Smack checks of semaphore operations
2007 * @sma: the object
2008 * @sops: unused
2009 * @nsops: unused
2010 * @alter: unused
2011 *
2012 * Treated as read and write in all cases.
2013 *
2014 * Returns 0 if access is allowed, error code otherwise
2015 */
2016static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
2017 unsigned nsops, int alter)
2018{
Etienne Bassetecfcc532009-04-08 20:40:06 +02002019 return smk_curacc_sem(sma, MAY_READWRITE);
Casey Schauflere114e472008-02-04 22:29:50 -08002020}
2021
2022/**
2023 * smack_msg_alloc_security - Set the security blob for msg
2024 * @msq: the object
2025 *
2026 * Returns 0
2027 */
2028static int smack_msg_queue_alloc_security(struct msg_queue *msq)
2029{
2030 struct kern_ipc_perm *kisp = &msq->q_perm;
2031
David Howells86a264a2008-11-14 10:39:18 +11002032 kisp->security = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08002033 return 0;
2034}
2035
2036/**
2037 * smack_msg_free_security - Clear the security blob for msg
2038 * @msq: the object
2039 *
2040 * Clears the blob pointer
2041 */
2042static void smack_msg_queue_free_security(struct msg_queue *msq)
2043{
2044 struct kern_ipc_perm *kisp = &msq->q_perm;
2045
2046 kisp->security = NULL;
2047}
2048
2049/**
2050 * smack_of_msq - the smack pointer for the msq
2051 * @msq: the object
2052 *
2053 * Returns a pointer to the smack value
2054 */
2055static char *smack_of_msq(struct msg_queue *msq)
2056{
2057 return (char *)msq->q_perm.security;
2058}
2059
2060/**
Etienne Bassetecfcc532009-04-08 20:40:06 +02002061 * smk_curacc_msq : helper to check if current has access on msq
2062 * @msq : the msq
2063 * @access : access requested
2064 *
2065 * return 0 if current has access, error otherwise
2066 */
2067static int smk_curacc_msq(struct msg_queue *msq, int access)
2068{
2069 char *msp = smack_of_msq(msq);
2070 struct smk_audit_info ad;
2071
2072#ifdef CONFIG_AUDIT
2073 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2074 ad.a.u.ipc_id = msq->q_perm.id;
2075#endif
2076 return smk_curacc(msp, access, &ad);
2077}
2078
2079/**
Casey Schauflere114e472008-02-04 22:29:50 -08002080 * smack_msg_queue_associate - Smack access check for msg_queue
2081 * @msq: the object
2082 * @msqflg: access requested
2083 *
2084 * Returns 0 if current has the requested access, error code otherwise
2085 */
2086static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
2087{
Casey Schauflere114e472008-02-04 22:29:50 -08002088 int may;
2089
2090 may = smack_flags_to_may(msqflg);
Etienne Bassetecfcc532009-04-08 20:40:06 +02002091 return smk_curacc_msq(msq, may);
Casey Schauflere114e472008-02-04 22:29:50 -08002092}
2093
2094/**
2095 * smack_msg_queue_msgctl - Smack access check for msg_queue
2096 * @msq: the object
2097 * @cmd: what it wants to do
2098 *
2099 * Returns 0 if current has the requested access, error code otherwise
2100 */
2101static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
2102{
Casey Schauflere114e472008-02-04 22:29:50 -08002103 int may;
2104
2105 switch (cmd) {
2106 case IPC_STAT:
2107 case MSG_STAT:
2108 may = MAY_READ;
2109 break;
2110 case IPC_SET:
2111 case IPC_RMID:
2112 may = MAY_READWRITE;
2113 break;
2114 case IPC_INFO:
2115 case MSG_INFO:
2116 /*
2117 * System level information
2118 */
2119 return 0;
2120 default:
2121 return -EINVAL;
2122 }
2123
Etienne Bassetecfcc532009-04-08 20:40:06 +02002124 return smk_curacc_msq(msq, may);
Casey Schauflere114e472008-02-04 22:29:50 -08002125}
2126
2127/**
2128 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2129 * @msq: the object
2130 * @msg: unused
2131 * @msqflg: access requested
2132 *
2133 * Returns 0 if current has the requested access, error code otherwise
2134 */
2135static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
2136 int msqflg)
2137{
Etienne Bassetecfcc532009-04-08 20:40:06 +02002138 int may;
Casey Schauflere114e472008-02-04 22:29:50 -08002139
Etienne Bassetecfcc532009-04-08 20:40:06 +02002140 may = smack_flags_to_may(msqflg);
2141 return smk_curacc_msq(msq, may);
Casey Schauflere114e472008-02-04 22:29:50 -08002142}
2143
2144/**
2145 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2146 * @msq: the object
2147 * @msg: unused
2148 * @target: unused
2149 * @type: unused
2150 * @mode: unused
2151 *
2152 * Returns 0 if current has read and write access, error code otherwise
2153 */
2154static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
2155 struct task_struct *target, long type, int mode)
2156{
Etienne Bassetecfcc532009-04-08 20:40:06 +02002157 return smk_curacc_msq(msq, MAY_READWRITE);
Casey Schauflere114e472008-02-04 22:29:50 -08002158}
2159
2160/**
2161 * smack_ipc_permission - Smack access for ipc_permission()
2162 * @ipp: the object permissions
2163 * @flag: access requested
2164 *
2165 * Returns 0 if current has read and write access, error code otherwise
2166 */
2167static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
2168{
2169 char *isp = ipp->security;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002170 int may = smack_flags_to_may(flag);
2171 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002172
Etienne Bassetecfcc532009-04-08 20:40:06 +02002173#ifdef CONFIG_AUDIT
2174 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2175 ad.a.u.ipc_id = ipp->id;
2176#endif
2177 return smk_curacc(isp, may, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08002178}
2179
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002180/**
2181 * smack_ipc_getsecid - Extract smack security id
Randy Dunlap251a2a92009-02-18 11:42:33 -08002182 * @ipp: the object permissions
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002183 * @secid: where result will be saved
2184 */
2185static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
2186{
2187 char *smack = ipp->security;
2188
2189 *secid = smack_to_secid(smack);
2190}
2191
Casey Schauflere114e472008-02-04 22:29:50 -08002192/**
2193 * smack_d_instantiate - Make sure the blob is correct on an inode
2194 * @opt_dentry: unused
2195 * @inode: the object
2196 *
2197 * Set the inode's security blob if it hasn't been done already.
2198 */
2199static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
2200{
2201 struct super_block *sbp;
2202 struct superblock_smack *sbsp;
2203 struct inode_smack *isp;
David Howells86a264a2008-11-14 10:39:18 +11002204 char *csp = current_security();
Casey Schauflere114e472008-02-04 22:29:50 -08002205 char *fetched;
2206 char *final;
2207 struct dentry *dp;
2208
2209 if (inode == NULL)
2210 return;
2211
2212 isp = inode->i_security;
2213
2214 mutex_lock(&isp->smk_lock);
2215 /*
2216 * If the inode is already instantiated
2217 * take the quick way out
2218 */
2219 if (isp->smk_flags & SMK_INODE_INSTANT)
2220 goto unlockandout;
2221
2222 sbp = inode->i_sb;
2223 sbsp = sbp->s_security;
2224 /*
2225 * We're going to use the superblock default label
2226 * if there's no label on the file.
2227 */
2228 final = sbsp->smk_default;
2229
2230 /*
Casey Schauflere97dcb02008-06-02 10:04:32 -07002231 * If this is the root inode the superblock
2232 * may be in the process of initialization.
2233 * If that is the case use the root value out
2234 * of the superblock.
2235 */
2236 if (opt_dentry->d_parent == opt_dentry) {
2237 isp->smk_inode = sbsp->smk_root;
2238 isp->smk_flags |= SMK_INODE_INSTANT;
2239 goto unlockandout;
2240 }
2241
2242 /*
Casey Schauflere114e472008-02-04 22:29:50 -08002243 * This is pretty hackish.
2244 * Casey says that we shouldn't have to do
2245 * file system specific code, but it does help
2246 * with keeping it simple.
2247 */
2248 switch (sbp->s_magic) {
2249 case SMACK_MAGIC:
2250 /*
2251 * Casey says that it's a little embarassing
2252 * that the smack file system doesn't do
2253 * extended attributes.
2254 */
2255 final = smack_known_star.smk_known;
2256 break;
2257 case PIPEFS_MAGIC:
2258 /*
2259 * Casey says pipes are easy (?)
2260 */
2261 final = smack_known_star.smk_known;
2262 break;
2263 case DEVPTS_SUPER_MAGIC:
2264 /*
2265 * devpts seems content with the label of the task.
2266 * Programs that change smack have to treat the
2267 * pty with respect.
2268 */
2269 final = csp;
2270 break;
2271 case SOCKFS_MAGIC:
2272 /*
2273 * Casey says sockets get the smack of the task.
2274 */
2275 final = csp;
2276 break;
2277 case PROC_SUPER_MAGIC:
2278 /*
2279 * Casey says procfs appears not to care.
2280 * The superblock default suffices.
2281 */
2282 break;
2283 case TMPFS_MAGIC:
2284 /*
2285 * Device labels should come from the filesystem,
2286 * but watch out, because they're volitile,
2287 * getting recreated on every reboot.
2288 */
2289 final = smack_known_star.smk_known;
2290 /*
2291 * No break.
2292 *
2293 * If a smack value has been set we want to use it,
2294 * but since tmpfs isn't giving us the opportunity
2295 * to set mount options simulate setting the
2296 * superblock default.
2297 */
2298 default:
2299 /*
2300 * This isn't an understood special case.
2301 * Get the value from the xattr.
2302 *
2303 * No xattr support means, alas, no SMACK label.
2304 * Use the aforeapplied default.
2305 * It would be curious if the label of the task
2306 * does not match that assigned.
2307 */
2308 if (inode->i_op->getxattr == NULL)
2309 break;
2310 /*
2311 * Get the dentry for xattr.
2312 */
2313 if (opt_dentry == NULL) {
2314 dp = d_find_alias(inode);
2315 if (dp == NULL)
2316 break;
2317 } else {
2318 dp = dget(opt_dentry);
2319 if (dp == NULL)
2320 break;
2321 }
2322
2323 fetched = smk_fetch(inode, dp);
2324 if (fetched != NULL)
2325 final = fetched;
2326
2327 dput(dp);
2328 break;
2329 }
2330
2331 if (final == NULL)
2332 isp->smk_inode = csp;
2333 else
2334 isp->smk_inode = final;
2335
2336 isp->smk_flags |= SMK_INODE_INSTANT;
2337
2338unlockandout:
2339 mutex_unlock(&isp->smk_lock);
2340 return;
2341}
2342
2343/**
2344 * smack_getprocattr - Smack process attribute access
2345 * @p: the object task
2346 * @name: the name of the attribute in /proc/.../attr
2347 * @value: where to put the result
2348 *
2349 * Places a copy of the task Smack into value
2350 *
2351 * Returns the length of the smack label or an error code
2352 */
2353static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2354{
2355 char *cp;
2356 int slen;
2357
2358 if (strcmp(name, "current") != 0)
2359 return -EINVAL;
2360
David Howellsc69e8d92008-11-14 10:39:19 +11002361 cp = kstrdup(task_security(p), GFP_KERNEL);
Casey Schauflere114e472008-02-04 22:29:50 -08002362 if (cp == NULL)
2363 return -ENOMEM;
2364
2365 slen = strlen(cp);
2366 *value = cp;
2367 return slen;
2368}
2369
2370/**
2371 * smack_setprocattr - Smack process attribute setting
2372 * @p: the object task
2373 * @name: the name of the attribute in /proc/.../attr
2374 * @value: the value to set
2375 * @size: the size of the value
2376 *
2377 * Sets the Smack value of the task. Only setting self
2378 * is permitted and only with privilege
2379 *
2380 * Returns the length of the smack label or an error code
2381 */
2382static int smack_setprocattr(struct task_struct *p, char *name,
2383 void *value, size_t size)
2384{
David Howellsd84f4f92008-11-14 10:39:23 +11002385 struct cred *new;
Casey Schauflere114e472008-02-04 22:29:50 -08002386 char *newsmack;
2387
Casey Schauflere114e472008-02-04 22:29:50 -08002388 /*
2389 * Changing another process' Smack value is too dangerous
2390 * and supports no sane use case.
2391 */
2392 if (p != current)
2393 return -EPERM;
2394
David Howells5cd9c582008-08-14 11:37:28 +01002395 if (!capable(CAP_MAC_ADMIN))
2396 return -EPERM;
2397
Casey Schauflere114e472008-02-04 22:29:50 -08002398 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2399 return -EINVAL;
2400
2401 if (strcmp(name, "current") != 0)
2402 return -EINVAL;
2403
2404 newsmack = smk_import(value, size);
2405 if (newsmack == NULL)
2406 return -EINVAL;
2407
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002408 /*
2409 * No process is ever allowed the web ("@") label.
2410 */
2411 if (newsmack == smack_known_web.smk_known)
2412 return -EPERM;
2413
David Howellsd84f4f92008-11-14 10:39:23 +11002414 new = prepare_creds();
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002415 if (new == NULL)
David Howellsd84f4f92008-11-14 10:39:23 +11002416 return -ENOMEM;
2417 new->security = newsmack;
2418 commit_creds(new);
Casey Schauflere114e472008-02-04 22:29:50 -08002419 return size;
2420}
2421
2422/**
2423 * smack_unix_stream_connect - Smack access on UDS
2424 * @sock: one socket
2425 * @other: the other socket
2426 * @newsk: unused
2427 *
2428 * Return 0 if a subject with the smack of sock could access
2429 * an object with the smack of other, otherwise an error code
2430 */
2431static int smack_unix_stream_connect(struct socket *sock,
2432 struct socket *other, struct sock *newsk)
2433{
2434 struct inode *sp = SOCK_INODE(sock);
2435 struct inode *op = SOCK_INODE(other);
Etienne Bassetecfcc532009-04-08 20:40:06 +02002436 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002437
Etienne Bassetecfcc532009-04-08 20:40:06 +02002438 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2439 smk_ad_setfield_u_net_sk(&ad, other->sk);
2440 return smk_access(smk_of_inode(sp), smk_of_inode(op),
2441 MAY_READWRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08002442}
2443
2444/**
2445 * smack_unix_may_send - Smack access on UDS
2446 * @sock: one socket
2447 * @other: the other socket
2448 *
2449 * Return 0 if a subject with the smack of sock could access
2450 * an object with the smack of other, otherwise an error code
2451 */
2452static int smack_unix_may_send(struct socket *sock, struct socket *other)
2453{
2454 struct inode *sp = SOCK_INODE(sock);
2455 struct inode *op = SOCK_INODE(other);
Etienne Bassetecfcc532009-04-08 20:40:06 +02002456 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002457
Etienne Bassetecfcc532009-04-08 20:40:06 +02002458 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2459 smk_ad_setfield_u_net_sk(&ad, other->sk);
2460 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08002461}
2462
2463/**
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002464 * smack_socket_sendmsg - Smack check based on destination host
2465 * @sock: the socket
Randy Dunlap251a2a92009-02-18 11:42:33 -08002466 * @msg: the message
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002467 * @size: the size of the message
2468 *
2469 * Return 0 if the current subject can write to the destination
2470 * host. This is only a question if the destination is a single
2471 * label host.
2472 */
2473static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
2474 int size)
2475{
2476 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002477
2478 /*
2479 * Perfectly reasonable for this to be NULL
2480 */
Julia Lawallda34d422009-08-05 14:34:55 +02002481 if (sip == NULL || sip->sin_family != AF_INET)
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002482 return 0;
2483
Paul Moore07feee82009-03-27 17:10:54 -04002484 return smack_netlabel_send(sock->sk, sip);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002485}
2486
2487
2488/**
Randy Dunlap251a2a92009-02-18 11:42:33 -08002489 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
Casey Schauflere114e472008-02-04 22:29:50 -08002490 * @sap: netlabel secattr
2491 * @sip: where to put the result
2492 *
2493 * Copies a smack label into sip
2494 */
2495static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2496{
2497 char smack[SMK_LABELLEN];
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002498 char *sp;
Casey Schauflere114e472008-02-04 22:29:50 -08002499 int pcat;
2500
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002501 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
Casey Schauflere114e472008-02-04 22:29:50 -08002502 /*
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002503 * Looks like a CIPSO packet.
Casey Schauflere114e472008-02-04 22:29:50 -08002504 * If there are flags but no level netlabel isn't
2505 * behaving the way we expect it to.
2506 *
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002507 * Get the categories, if any
Casey Schauflere114e472008-02-04 22:29:50 -08002508 * Without guidance regarding the smack value
2509 * for the packet fall back on the network
2510 * ambient value.
2511 */
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002512 memset(smack, '\0', SMK_LABELLEN);
2513 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2514 for (pcat = -1;;) {
2515 pcat = netlbl_secattr_catmap_walk(
2516 sap->attr.mls.cat, pcat + 1);
2517 if (pcat < 0)
2518 break;
2519 smack_catset_bit(pcat, smack);
2520 }
2521 /*
2522 * If it is CIPSO using smack direct mapping
2523 * we are already done. WeeHee.
2524 */
2525 if (sap->attr.mls.lvl == smack_cipso_direct) {
2526 memcpy(sip, smack, SMK_MAXLEN);
2527 return;
Casey Schauflere114e472008-02-04 22:29:50 -08002528 }
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002529 /*
2530 * Look it up in the supplied table if it is not
2531 * a direct mapping.
2532 */
2533 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
2534 return;
2535 }
2536 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
2537 /*
2538 * Looks like a fallback, which gives us a secid.
2539 */
2540 sp = smack_from_secid(sap->attr.secid);
2541 /*
2542 * This has got to be a bug because it is
2543 * impossible to specify a fallback without
2544 * specifying the label, which will ensure
2545 * it has a secid, and the only way to get a
2546 * secid is from a fallback.
2547 */
2548 BUG_ON(sp == NULL);
2549 strncpy(sip, sp, SMK_MAXLEN);
Casey Schauflere114e472008-02-04 22:29:50 -08002550 return;
2551 }
2552 /*
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002553 * Without guidance regarding the smack value
2554 * for the packet fall back on the network
2555 * ambient value.
Casey Schauflere114e472008-02-04 22:29:50 -08002556 */
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002557 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
Casey Schauflere114e472008-02-04 22:29:50 -08002558 return;
2559}
2560
2561/**
2562 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2563 * @sk: socket
2564 * @skb: packet
2565 *
2566 * Returns 0 if the packet should be delivered, an error code otherwise
2567 */
2568static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2569{
2570 struct netlbl_lsm_secattr secattr;
2571 struct socket_smack *ssp = sk->sk_security;
2572 char smack[SMK_LABELLEN];
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002573 char *csp;
Casey Schauflere114e472008-02-04 22:29:50 -08002574 int rc;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002575 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002576 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2577 return 0;
2578
2579 /*
2580 * Translate what netlabel gave us.
2581 */
Casey Schauflere114e472008-02-04 22:29:50 -08002582 netlbl_secattr_init(&secattr);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002583
Casey Schauflere114e472008-02-04 22:29:50 -08002584 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002585 if (rc == 0) {
Casey Schauflere114e472008-02-04 22:29:50 -08002586 smack_from_secattr(&secattr, smack);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002587 csp = smack;
2588 } else
2589 csp = smack_net_ambient;
2590
Casey Schauflere114e472008-02-04 22:29:50 -08002591 netlbl_secattr_destroy(&secattr);
Casey Schaufler6d3dc072008-12-31 12:54:12 -05002592
Etienne Bassetecfcc532009-04-08 20:40:06 +02002593#ifdef CONFIG_AUDIT
2594 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2595 ad.a.u.net.family = sk->sk_family;
Eric Dumazet8964be42009-11-20 15:35:04 -08002596 ad.a.u.net.netif = skb->skb_iif;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002597 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
2598#endif
Casey Schauflere114e472008-02-04 22:29:50 -08002599 /*
2600 * Receiving a packet requires that the other end
2601 * be able to write here. Read access is not required.
2602 * This is the simplist possible security model
2603 * for networking.
2604 */
Etienne Bassetecfcc532009-04-08 20:40:06 +02002605 rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
Paul Moorea8134292008-10-10 10:16:31 -04002606 if (rc != 0)
2607 netlbl_skbuff_err(skb, rc, 0);
2608 return rc;
Casey Schauflere114e472008-02-04 22:29:50 -08002609}
2610
2611/**
2612 * smack_socket_getpeersec_stream - pull in packet label
2613 * @sock: the socket
2614 * @optval: user's destination
2615 * @optlen: size thereof
Randy Dunlap251a2a92009-02-18 11:42:33 -08002616 * @len: max thereof
Casey Schauflere114e472008-02-04 22:29:50 -08002617 *
2618 * returns zero on success, an error code otherwise
2619 */
2620static int smack_socket_getpeersec_stream(struct socket *sock,
2621 char __user *optval,
2622 int __user *optlen, unsigned len)
2623{
2624 struct socket_smack *ssp;
2625 int slen;
2626 int rc = 0;
2627
2628 ssp = sock->sk->sk_security;
2629 slen = strlen(ssp->smk_packet) + 1;
2630
2631 if (slen > len)
2632 rc = -ERANGE;
2633 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2634 rc = -EFAULT;
2635
2636 if (put_user(slen, optlen) != 0)
2637 rc = -EFAULT;
2638
2639 return rc;
2640}
2641
2642
2643/**
2644 * smack_socket_getpeersec_dgram - pull in packet label
2645 * @sock: the socket
2646 * @skb: packet data
2647 * @secid: pointer to where to put the secid of the packet
2648 *
2649 * Sets the netlabel socket state on sk from parent
2650 */
2651static int smack_socket_getpeersec_dgram(struct socket *sock,
2652 struct sk_buff *skb, u32 *secid)
2653
2654{
2655 struct netlbl_lsm_secattr secattr;
2656 struct sock *sk;
2657 char smack[SMK_LABELLEN];
2658 int family = PF_INET;
2659 u32 s;
2660 int rc;
2661
2662 /*
2663 * Only works for families with packets.
2664 */
2665 if (sock != NULL) {
2666 sk = sock->sk;
2667 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2668 return 0;
2669 family = sk->sk_family;
2670 }
2671 /*
2672 * Translate what netlabel gave us.
2673 */
Casey Schauflere114e472008-02-04 22:29:50 -08002674 netlbl_secattr_init(&secattr);
2675 rc = netlbl_skbuff_getattr(skb, family, &secattr);
2676 if (rc == 0)
2677 smack_from_secattr(&secattr, smack);
2678 netlbl_secattr_destroy(&secattr);
2679
2680 /*
2681 * Give up if we couldn't get anything
2682 */
2683 if (rc != 0)
2684 return rc;
2685
2686 s = smack_to_secid(smack);
2687 if (s == 0)
2688 return -EINVAL;
2689
2690 *secid = s;
2691 return 0;
2692}
2693
2694/**
Paul Moore07feee82009-03-27 17:10:54 -04002695 * smack_sock_graft - Initialize a newly created socket with an existing sock
2696 * @sk: child sock
2697 * @parent: parent socket
Casey Schauflere114e472008-02-04 22:29:50 -08002698 *
Paul Moore07feee82009-03-27 17:10:54 -04002699 * Set the smk_{in,out} state of an existing sock based on the process that
2700 * is creating the new socket.
Casey Schauflere114e472008-02-04 22:29:50 -08002701 */
2702static void smack_sock_graft(struct sock *sk, struct socket *parent)
2703{
2704 struct socket_smack *ssp;
Casey Schauflere114e472008-02-04 22:29:50 -08002705
Paul Moore07feee82009-03-27 17:10:54 -04002706 if (sk == NULL ||
2707 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
Casey Schauflere114e472008-02-04 22:29:50 -08002708 return;
2709
2710 ssp = sk->sk_security;
David Howells86a264a2008-11-14 10:39:18 +11002711 ssp->smk_in = ssp->smk_out = current_security();
Paul Moore07feee82009-03-27 17:10:54 -04002712 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
Casey Schauflere114e472008-02-04 22:29:50 -08002713}
2714
2715/**
2716 * smack_inet_conn_request - Smack access check on connect
2717 * @sk: socket involved
2718 * @skb: packet
2719 * @req: unused
2720 *
2721 * Returns 0 if a task with the packet label could write to
2722 * the socket, otherwise an error code
2723 */
2724static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
2725 struct request_sock *req)
2726{
Paul Moore07feee82009-03-27 17:10:54 -04002727 u16 family = sk->sk_family;
Casey Schauflere114e472008-02-04 22:29:50 -08002728 struct socket_smack *ssp = sk->sk_security;
Paul Moore07feee82009-03-27 17:10:54 -04002729 struct netlbl_lsm_secattr secattr;
2730 struct sockaddr_in addr;
2731 struct iphdr *hdr;
Casey Schauflere114e472008-02-04 22:29:50 -08002732 char smack[SMK_LABELLEN];
2733 int rc;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002734 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002735
Paul Moore07feee82009-03-27 17:10:54 -04002736 /* handle mapped IPv4 packets arriving via IPv6 sockets */
2737 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
2738 family = PF_INET;
Casey Schauflere114e472008-02-04 22:29:50 -08002739
Paul Moore07feee82009-03-27 17:10:54 -04002740 netlbl_secattr_init(&secattr);
2741 rc = netlbl_skbuff_getattr(skb, family, &secattr);
Casey Schauflere114e472008-02-04 22:29:50 -08002742 if (rc == 0)
Paul Moore07feee82009-03-27 17:10:54 -04002743 smack_from_secattr(&secattr, smack);
Casey Schauflere114e472008-02-04 22:29:50 -08002744 else
2745 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
Paul Moore07feee82009-03-27 17:10:54 -04002746 netlbl_secattr_destroy(&secattr);
2747
Etienne Bassetecfcc532009-04-08 20:40:06 +02002748#ifdef CONFIG_AUDIT
2749 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET);
2750 ad.a.u.net.family = family;
Eric Dumazet8964be42009-11-20 15:35:04 -08002751 ad.a.u.net.netif = skb->skb_iif;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002752 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
2753#endif
Casey Schauflere114e472008-02-04 22:29:50 -08002754 /*
Paul Moore07feee82009-03-27 17:10:54 -04002755 * Receiving a packet requires that the other end be able to write
2756 * here. Read access is not required.
Casey Schauflere114e472008-02-04 22:29:50 -08002757 */
Etienne Bassetecfcc532009-04-08 20:40:06 +02002758 rc = smk_access(smack, ssp->smk_in, MAY_WRITE, &ad);
Paul Moore07feee82009-03-27 17:10:54 -04002759 if (rc != 0)
2760 return rc;
2761
2762 /*
2763 * Save the peer's label in the request_sock so we can later setup
2764 * smk_packet in the child socket so that SO_PEERCRED can report it.
2765 */
2766 req->peer_secid = smack_to_secid(smack);
2767
2768 /*
2769 * We need to decide if we want to label the incoming connection here
2770 * if we do we only need to label the request_sock and the stack will
2771 * propogate the wire-label to the sock when it is created.
2772 */
2773 hdr = ip_hdr(skb);
2774 addr.sin_addr.s_addr = hdr->saddr;
2775 rcu_read_lock();
2776 if (smack_host_label(&addr) == NULL) {
2777 rcu_read_unlock();
2778 netlbl_secattr_init(&secattr);
2779 smack_to_secattr(smack, &secattr);
2780 rc = netlbl_req_setattr(req, &secattr);
2781 netlbl_secattr_destroy(&secattr);
2782 } else {
2783 rcu_read_unlock();
2784 netlbl_req_delattr(req);
2785 }
Casey Schauflere114e472008-02-04 22:29:50 -08002786
2787 return rc;
2788}
2789
Paul Moore07feee82009-03-27 17:10:54 -04002790/**
2791 * smack_inet_csk_clone - Copy the connection information to the new socket
2792 * @sk: the new socket
2793 * @req: the connection's request_sock
2794 *
2795 * Transfer the connection's peer label to the newly created socket.
2796 */
2797static void smack_inet_csk_clone(struct sock *sk,
2798 const struct request_sock *req)
2799{
2800 struct socket_smack *ssp = sk->sk_security;
2801 char *smack;
2802
2803 if (req->peer_secid != 0) {
2804 smack = smack_from_secid(req->peer_secid);
2805 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
2806 } else
2807 ssp->smk_packet[0] = '\0';
2808}
2809
Casey Schauflere114e472008-02-04 22:29:50 -08002810/*
2811 * Key management security hooks
2812 *
2813 * Casey has not tested key support very heavily.
2814 * The permission check is most likely too restrictive.
2815 * If you care about keys please have a look.
2816 */
2817#ifdef CONFIG_KEYS
2818
2819/**
2820 * smack_key_alloc - Set the key security blob
2821 * @key: object
David Howellsd84f4f92008-11-14 10:39:23 +11002822 * @cred: the credentials to use
Casey Schauflere114e472008-02-04 22:29:50 -08002823 * @flags: unused
2824 *
2825 * No allocation required
2826 *
2827 * Returns 0
2828 */
David Howellsd84f4f92008-11-14 10:39:23 +11002829static int smack_key_alloc(struct key *key, const struct cred *cred,
Casey Schauflere114e472008-02-04 22:29:50 -08002830 unsigned long flags)
2831{
David Howellsd84f4f92008-11-14 10:39:23 +11002832 key->security = cred->security;
Casey Schauflere114e472008-02-04 22:29:50 -08002833 return 0;
2834}
2835
2836/**
2837 * smack_key_free - Clear the key security blob
2838 * @key: the object
2839 *
2840 * Clear the blob pointer
2841 */
2842static void smack_key_free(struct key *key)
2843{
2844 key->security = NULL;
2845}
2846
2847/*
2848 * smack_key_permission - Smack access on a key
2849 * @key_ref: gets to the object
David Howellsd84f4f92008-11-14 10:39:23 +11002850 * @cred: the credentials to use
Casey Schauflere114e472008-02-04 22:29:50 -08002851 * @perm: unused
2852 *
2853 * Return 0 if the task has read and write to the object,
2854 * an error code otherwise
2855 */
2856static int smack_key_permission(key_ref_t key_ref,
David Howellsd84f4f92008-11-14 10:39:23 +11002857 const struct cred *cred, key_perm_t perm)
Casey Schauflere114e472008-02-04 22:29:50 -08002858{
2859 struct key *keyp;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002860 struct smk_audit_info ad;
Casey Schauflere114e472008-02-04 22:29:50 -08002861
2862 keyp = key_ref_to_ptr(key_ref);
2863 if (keyp == NULL)
2864 return -EINVAL;
2865 /*
2866 * If the key hasn't been initialized give it access so that
2867 * it may do so.
2868 */
2869 if (keyp->security == NULL)
2870 return 0;
2871 /*
2872 * This should not occur
2873 */
David Howellsd84f4f92008-11-14 10:39:23 +11002874 if (cred->security == NULL)
Casey Schauflere114e472008-02-04 22:29:50 -08002875 return -EACCES;
Etienne Bassetecfcc532009-04-08 20:40:06 +02002876#ifdef CONFIG_AUDIT
2877 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
2878 ad.a.u.key_struct.key = keyp->serial;
2879 ad.a.u.key_struct.key_desc = keyp->description;
2880#endif
2881 return smk_access(cred->security, keyp->security,
2882 MAY_READWRITE, &ad);
Casey Schauflere114e472008-02-04 22:29:50 -08002883}
2884#endif /* CONFIG_KEYS */
2885
2886/*
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002887 * Smack Audit hooks
2888 *
2889 * Audit requires a unique representation of each Smack specific
2890 * rule. This unique representation is used to distinguish the
2891 * object to be audited from remaining kernel objects and also
2892 * works as a glue between the audit hooks.
2893 *
2894 * Since repository entries are added but never deleted, we'll use
2895 * the smack_known label address related to the given audit rule as
2896 * the needed unique representation. This also better fits the smack
2897 * model where nearly everything is a label.
2898 */
2899#ifdef CONFIG_AUDIT
2900
2901/**
2902 * smack_audit_rule_init - Initialize a smack audit rule
2903 * @field: audit rule fields given from user-space (audit.h)
2904 * @op: required testing operator (=, !=, >, <, ...)
2905 * @rulestr: smack label to be audited
2906 * @vrule: pointer to save our own audit rule representation
2907 *
2908 * Prepare to audit cases where (@field @op @rulestr) is true.
2909 * The label to be audited is created if necessay.
2910 */
2911static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2912{
2913 char **rule = (char **)vrule;
2914 *rule = NULL;
2915
2916 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2917 return -EINVAL;
2918
Al Viro5af75d82008-12-16 05:59:26 -05002919 if (op != Audit_equal && op != Audit_not_equal)
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002920 return -EINVAL;
2921
2922 *rule = smk_import(rulestr, 0);
2923
2924 return 0;
2925}
2926
2927/**
2928 * smack_audit_rule_known - Distinguish Smack audit rules
2929 * @krule: rule of interest, in Audit kernel representation format
2930 *
2931 * This is used to filter Smack rules from remaining Audit ones.
2932 * If it's proved that this rule belongs to us, the
2933 * audit_rule_match hook will be called to do the final judgement.
2934 */
2935static int smack_audit_rule_known(struct audit_krule *krule)
2936{
2937 struct audit_field *f;
2938 int i;
2939
2940 for (i = 0; i < krule->field_count; i++) {
2941 f = &krule->fields[i];
2942
2943 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
2944 return 1;
2945 }
2946
2947 return 0;
2948}
2949
2950/**
2951 * smack_audit_rule_match - Audit given object ?
2952 * @secid: security id for identifying the object to test
2953 * @field: audit rule flags given from user-space
2954 * @op: required testing operator
2955 * @vrule: smack internal rule presentation
2956 * @actx: audit context associated with the check
2957 *
2958 * The core Audit hook. It's used to take the decision of
2959 * whether to audit or not to audit a given object.
2960 */
2961static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
2962 struct audit_context *actx)
2963{
2964 char *smack;
2965 char *rule = vrule;
2966
2967 if (!rule) {
2968 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
2969 "Smack: missing rule\n");
2970 return -ENOENT;
2971 }
2972
2973 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2974 return 0;
2975
2976 smack = smack_from_secid(secid);
2977
2978 /*
2979 * No need to do string comparisons. If a match occurs,
2980 * both pointers will point to the same smack_known
2981 * label.
2982 */
Al Viro5af75d82008-12-16 05:59:26 -05002983 if (op == Audit_equal)
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002984 return (rule == smack);
Al Viro5af75d82008-12-16 05:59:26 -05002985 if (op == Audit_not_equal)
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10002986 return (rule != smack);
2987
2988 return 0;
2989}
2990
2991/**
2992 * smack_audit_rule_free - free smack rule representation
2993 * @vrule: rule to be freed.
2994 *
2995 * No memory was allocated.
2996 */
2997static void smack_audit_rule_free(void *vrule)
2998{
2999 /* No-op */
3000}
3001
3002#endif /* CONFIG_AUDIT */
3003
Randy Dunlap251a2a92009-02-18 11:42:33 -08003004/**
Casey Schauflere114e472008-02-04 22:29:50 -08003005 * smack_secid_to_secctx - return the smack label for a secid
3006 * @secid: incoming integer
3007 * @secdata: destination
3008 * @seclen: how long it is
3009 *
3010 * Exists for networking code.
3011 */
3012static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
3013{
3014 char *sp = smack_from_secid(secid);
3015
3016 *secdata = sp;
3017 *seclen = strlen(sp);
3018 return 0;
3019}
3020
Randy Dunlap251a2a92009-02-18 11:42:33 -08003021/**
Casey Schaufler4bc87e62008-02-15 15:24:25 -08003022 * smack_secctx_to_secid - return the secid for a smack label
3023 * @secdata: smack label
3024 * @seclen: how long result is
3025 * @secid: outgoing integer
3026 *
3027 * Exists for audit and networking code.
3028 */
David Howellse52c17642008-04-29 20:52:51 +01003029static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
Casey Schaufler4bc87e62008-02-15 15:24:25 -08003030{
3031 *secid = smack_to_secid(secdata);
3032 return 0;
3033}
3034
Randy Dunlap251a2a92009-02-18 11:42:33 -08003035/**
Casey Schauflere114e472008-02-04 22:29:50 -08003036 * smack_release_secctx - don't do anything.
Randy Dunlap251a2a92009-02-18 11:42:33 -08003037 * @secdata: unused
3038 * @seclen: unused
Casey Schauflere114e472008-02-04 22:29:50 -08003039 *
3040 * Exists to make sure nothing gets done, and properly
3041 */
3042static void smack_release_secctx(char *secdata, u32 seclen)
3043{
3044}
3045
David P. Quigley1ee65e32009-09-03 14:25:57 -04003046static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
3047{
3048 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
3049}
3050
3051static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
3052{
3053 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
3054}
3055
3056static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
3057{
3058 int len = 0;
3059 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
3060
3061 if (len < 0)
3062 return len;
3063 *ctxlen = len;
3064 return 0;
3065}
3066
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +02003067struct security_operations smack_ops = {
3068 .name = "smack",
3069
Ingo Molnar9e488582009-05-07 19:26:19 +10003070 .ptrace_access_check = smack_ptrace_access_check,
David Howells5cd9c582008-08-14 11:37:28 +01003071 .ptrace_traceme = smack_ptrace_traceme,
Casey Schauflere114e472008-02-04 22:29:50 -08003072 .syslog = smack_syslog,
Casey Schauflere114e472008-02-04 22:29:50 -08003073
3074 .sb_alloc_security = smack_sb_alloc_security,
3075 .sb_free_security = smack_sb_free_security,
3076 .sb_copy_data = smack_sb_copy_data,
3077 .sb_kern_mount = smack_sb_kern_mount,
3078 .sb_statfs = smack_sb_statfs,
3079 .sb_mount = smack_sb_mount,
3080 .sb_umount = smack_sb_umount,
3081
3082 .inode_alloc_security = smack_inode_alloc_security,
3083 .inode_free_security = smack_inode_free_security,
3084 .inode_init_security = smack_inode_init_security,
3085 .inode_link = smack_inode_link,
3086 .inode_unlink = smack_inode_unlink,
3087 .inode_rmdir = smack_inode_rmdir,
3088 .inode_rename = smack_inode_rename,
3089 .inode_permission = smack_inode_permission,
3090 .inode_setattr = smack_inode_setattr,
3091 .inode_getattr = smack_inode_getattr,
3092 .inode_setxattr = smack_inode_setxattr,
3093 .inode_post_setxattr = smack_inode_post_setxattr,
3094 .inode_getxattr = smack_inode_getxattr,
3095 .inode_removexattr = smack_inode_removexattr,
3096 .inode_getsecurity = smack_inode_getsecurity,
3097 .inode_setsecurity = smack_inode_setsecurity,
3098 .inode_listsecurity = smack_inode_listsecurity,
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10003099 .inode_getsecid = smack_inode_getsecid,
Casey Schauflere114e472008-02-04 22:29:50 -08003100
3101 .file_permission = smack_file_permission,
3102 .file_alloc_security = smack_file_alloc_security,
3103 .file_free_security = smack_file_free_security,
3104 .file_ioctl = smack_file_ioctl,
3105 .file_lock = smack_file_lock,
3106 .file_fcntl = smack_file_fcntl,
3107 .file_set_fowner = smack_file_set_fowner,
3108 .file_send_sigiotask = smack_file_send_sigiotask,
3109 .file_receive = smack_file_receive,
3110
David Howellsee18d642009-09-02 09:14:21 +01003111 .cred_alloc_blank = smack_cred_alloc_blank,
David Howellsf1752ee2008-11-14 10:39:17 +11003112 .cred_free = smack_cred_free,
David Howellsd84f4f92008-11-14 10:39:23 +11003113 .cred_prepare = smack_cred_prepare,
David Howellsee18d642009-09-02 09:14:21 +01003114 .cred_transfer = smack_cred_transfer,
David Howells3a3b7ce2008-11-14 10:39:28 +11003115 .kernel_act_as = smack_kernel_act_as,
3116 .kernel_create_files_as = smack_kernel_create_files_as,
Casey Schauflere114e472008-02-04 22:29:50 -08003117 .task_setpgid = smack_task_setpgid,
3118 .task_getpgid = smack_task_getpgid,
3119 .task_getsid = smack_task_getsid,
3120 .task_getsecid = smack_task_getsecid,
3121 .task_setnice = smack_task_setnice,
3122 .task_setioprio = smack_task_setioprio,
3123 .task_getioprio = smack_task_getioprio,
3124 .task_setscheduler = smack_task_setscheduler,
3125 .task_getscheduler = smack_task_getscheduler,
3126 .task_movememory = smack_task_movememory,
3127 .task_kill = smack_task_kill,
3128 .task_wait = smack_task_wait,
Casey Schauflere114e472008-02-04 22:29:50 -08003129 .task_to_inode = smack_task_to_inode,
3130
3131 .ipc_permission = smack_ipc_permission,
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10003132 .ipc_getsecid = smack_ipc_getsecid,
Casey Schauflere114e472008-02-04 22:29:50 -08003133
3134 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
3135 .msg_msg_free_security = smack_msg_msg_free_security,
3136
3137 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
3138 .msg_queue_free_security = smack_msg_queue_free_security,
3139 .msg_queue_associate = smack_msg_queue_associate,
3140 .msg_queue_msgctl = smack_msg_queue_msgctl,
3141 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
3142 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
3143
3144 .shm_alloc_security = smack_shm_alloc_security,
3145 .shm_free_security = smack_shm_free_security,
3146 .shm_associate = smack_shm_associate,
3147 .shm_shmctl = smack_shm_shmctl,
3148 .shm_shmat = smack_shm_shmat,
3149
3150 .sem_alloc_security = smack_sem_alloc_security,
3151 .sem_free_security = smack_sem_free_security,
3152 .sem_associate = smack_sem_associate,
3153 .sem_semctl = smack_sem_semctl,
3154 .sem_semop = smack_sem_semop,
3155
Casey Schauflere114e472008-02-04 22:29:50 -08003156 .d_instantiate = smack_d_instantiate,
3157
3158 .getprocattr = smack_getprocattr,
3159 .setprocattr = smack_setprocattr,
3160
3161 .unix_stream_connect = smack_unix_stream_connect,
3162 .unix_may_send = smack_unix_may_send,
3163
3164 .socket_post_create = smack_socket_post_create,
Casey Schaufler6d3dc072008-12-31 12:54:12 -05003165 .socket_connect = smack_socket_connect,
3166 .socket_sendmsg = smack_socket_sendmsg,
Casey Schauflere114e472008-02-04 22:29:50 -08003167 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
3168 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
3169 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
3170 .sk_alloc_security = smack_sk_alloc_security,
3171 .sk_free_security = smack_sk_free_security,
3172 .sock_graft = smack_sock_graft,
3173 .inet_conn_request = smack_inet_conn_request,
Paul Moore07feee82009-03-27 17:10:54 -04003174 .inet_csk_clone = smack_inet_csk_clone,
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10003175
Casey Schauflere114e472008-02-04 22:29:50 -08003176 /* key management security hooks */
3177#ifdef CONFIG_KEYS
3178 .key_alloc = smack_key_alloc,
3179 .key_free = smack_key_free,
3180 .key_permission = smack_key_permission,
3181#endif /* CONFIG_KEYS */
Ahmed S. Darwishd20bdda2008-04-30 08:34:10 +10003182
3183 /* Audit hooks */
3184#ifdef CONFIG_AUDIT
3185 .audit_rule_init = smack_audit_rule_init,
3186 .audit_rule_known = smack_audit_rule_known,
3187 .audit_rule_match = smack_audit_rule_match,
3188 .audit_rule_free = smack_audit_rule_free,
3189#endif /* CONFIG_AUDIT */
3190
Casey Schauflere114e472008-02-04 22:29:50 -08003191 .secid_to_secctx = smack_secid_to_secctx,
Casey Schaufler4bc87e62008-02-15 15:24:25 -08003192 .secctx_to_secid = smack_secctx_to_secid,
Casey Schauflere114e472008-02-04 22:29:50 -08003193 .release_secctx = smack_release_secctx,
David P. Quigley1ee65e32009-09-03 14:25:57 -04003194 .inode_notifysecctx = smack_inode_notifysecctx,
3195 .inode_setsecctx = smack_inode_setsecctx,
3196 .inode_getsecctx = smack_inode_getsecctx,
Casey Schauflere114e472008-02-04 22:29:50 -08003197};
3198
Etienne Basset7198e2e2009-03-24 20:53:24 +01003199
3200static __init void init_smack_know_list(void)
3201{
3202 list_add(&smack_known_huh.list, &smack_known_list);
3203 list_add(&smack_known_hat.list, &smack_known_list);
3204 list_add(&smack_known_star.list, &smack_known_list);
3205 list_add(&smack_known_floor.list, &smack_known_list);
3206 list_add(&smack_known_invalid.list, &smack_known_list);
3207 list_add(&smack_known_web.list, &smack_known_list);
3208}
3209
Casey Schauflere114e472008-02-04 22:29:50 -08003210/**
3211 * smack_init - initialize the smack system
3212 *
3213 * Returns 0
3214 */
3215static __init int smack_init(void)
3216{
David Howellsd84f4f92008-11-14 10:39:23 +11003217 struct cred *cred;
3218
Ahmed S. Darwish076c54c2008-03-06 18:09:10 +02003219 if (!security_module_enable(&smack_ops))
3220 return 0;
3221
Casey Schauflere114e472008-02-04 22:29:50 -08003222 printk(KERN_INFO "Smack: Initializing.\n");
3223
3224 /*
3225 * Set the security state for the initial task.
3226 */
David Howellsd84f4f92008-11-14 10:39:23 +11003227 cred = (struct cred *) current->cred;
3228 cred->security = &smack_known_floor.smk_known;
Casey Schauflere114e472008-02-04 22:29:50 -08003229
Etienne Basset7198e2e2009-03-24 20:53:24 +01003230 /* initilize the smack_know_list */
3231 init_smack_know_list();
Casey Schauflere114e472008-02-04 22:29:50 -08003232 /*
3233 * Initialize locks
3234 */
Casey Schauflere114e472008-02-04 22:29:50 -08003235 spin_lock_init(&smack_known_huh.smk_cipsolock);
3236 spin_lock_init(&smack_known_hat.smk_cipsolock);
3237 spin_lock_init(&smack_known_star.smk_cipsolock);
3238 spin_lock_init(&smack_known_floor.smk_cipsolock);
3239 spin_lock_init(&smack_known_invalid.smk_cipsolock);
3240
3241 /*
3242 * Register with LSM
3243 */
3244 if (register_security(&smack_ops))
3245 panic("smack: Unable to register with kernel.\n");
3246
3247 return 0;
3248}
3249
3250/*
3251 * Smack requires early initialization in order to label
3252 * all processes and objects when they are created.
3253 */
3254security_initcall(smack_init);