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1 | /* |
2 | * Simplified MAC Kernel (smack) security module |
3 | * |
4 | * This file contains the smack hook function implementations. |
5 | * |
6 | * Authors: |
7 | * Casey Schaufler <casey@schaufler-ca.com> |
8 | * Jarkko Sakkinen <ext-jarkko.2.sakkinen@nokia.com> |
9 | * |
10 | * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> |
11 | * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. |
12 | * Paul Moore <paul.moore@hp.com> |
13 | * Copyright (C) 2010 Nokia Corporation |
14 | * |
15 | * This program is free software; you can redistribute it and/or modify |
16 | * it under the terms of the GNU General Public License version 2, |
17 | * as published by the Free Software Foundation. |
18 | */ |
19 | |
20 | #include <linux/xattr.h> |
21 | #include <linux/pagemap.h> |
22 | #include <linux/mount.h> |
23 | #include <linux/stat.h> |
24 | #include <linux/kd.h> |
25 | #include <asm/ioctls.h> |
26 | #include <linux/ip.h> |
27 | #include <linux/tcp.h> |
28 | #include <linux/udp.h> |
29 | #include <linux/slab.h> |
30 | #include <linux/mutex.h> |
31 | #include <linux/pipe_fs_i.h> |
32 | #include <net/netlabel.h> |
33 | #include <net/cipso_ipv4.h> |
34 | #include <linux/audit.h> |
35 | #include <linux/magic.h> |
36 | #include <linux/dcache.h> |
37 | #include "smack.h" |
38 | |
39 | #define task_security(task) (task_cred_xxx((task), security)) |
40 | |
41 | #define TRANS_TRUE "TRUE" |
42 | #define TRANS_TRUE_SIZE 4 |
43 | |
44 | /** |
45 | * smk_fetch - Fetch the smack label from a file. |
46 | * @ip: a pointer to the inode |
47 | * @dp: a pointer to the dentry |
48 | * |
49 | * Returns a pointer to the master list entry for the Smack label |
50 | * or NULL if there was no label to fetch. |
51 | */ |
52 | static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp) |
53 | { |
54 | int rc; |
55 | char in[SMK_LABELLEN]; |
56 | |
57 | if (ip->i_op->getxattr == NULL) |
58 | return NULL; |
59 | |
60 | rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN); |
61 | if (rc < 0) |
62 | return NULL; |
63 | |
64 | return smk_import(in, rc); |
65 | } |
66 | |
67 | /** |
68 | * new_inode_smack - allocate an inode security blob |
69 | * @smack: a pointer to the Smack label to use in the blob |
70 | * |
71 | * Returns the new blob or NULL if there's no memory available |
72 | */ |
73 | struct inode_smack *new_inode_smack(char *smack) |
74 | { |
75 | struct inode_smack *isp; |
76 | |
77 | isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL); |
78 | if (isp == NULL) |
79 | return NULL; |
80 | |
81 | isp->smk_inode = smack; |
82 | isp->smk_flags = 0; |
83 | mutex_init(&isp->smk_lock); |
84 | |
85 | return isp; |
86 | } |
87 | |
88 | /** |
89 | * new_task_smack - allocate a task security blob |
90 | * @smack: a pointer to the Smack label to use in the blob |
91 | * |
92 | * Returns the new blob or NULL if there's no memory available |
93 | */ |
94 | static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp) |
95 | { |
96 | struct task_smack *tsp; |
97 | |
98 | tsp = kzalloc(sizeof(struct task_smack), gfp); |
99 | if (tsp == NULL) |
100 | return NULL; |
101 | |
102 | tsp->smk_task = task; |
103 | tsp->smk_forked = forked; |
104 | INIT_LIST_HEAD(&tsp->smk_rules); |
105 | mutex_init(&tsp->smk_rules_lock); |
106 | |
107 | return tsp; |
108 | } |
109 | |
110 | /** |
111 | * smk_copy_rules - copy a rule set |
112 | * @nhead - new rules header pointer |
113 | * @ohead - old rules header pointer |
114 | * |
115 | * Returns 0 on success, -ENOMEM on error |
116 | */ |
117 | static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead, |
118 | gfp_t gfp) |
119 | { |
120 | struct smack_rule *nrp; |
121 | struct smack_rule *orp; |
122 | int rc = 0; |
123 | |
124 | INIT_LIST_HEAD(nhead); |
125 | |
126 | list_for_each_entry_rcu(orp, ohead, list) { |
127 | nrp = kzalloc(sizeof(struct smack_rule), gfp); |
128 | if (nrp == NULL) { |
129 | rc = -ENOMEM; |
130 | break; |
131 | } |
132 | *nrp = *orp; |
133 | list_add_rcu(&nrp->list, nhead); |
134 | } |
135 | return rc; |
136 | } |
137 | |
138 | /* |
139 | * LSM hooks. |
140 | * We he, that is fun! |
141 | */ |
142 | |
143 | /** |
144 | * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH |
145 | * @ctp: child task pointer |
146 | * @mode: ptrace attachment mode |
147 | * |
148 | * Returns 0 if access is OK, an error code otherwise |
149 | * |
150 | * Do the capability checks, and require read and write. |
151 | */ |
152 | static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) |
153 | { |
154 | int rc; |
155 | struct smk_audit_info ad; |
156 | char *tsp; |
157 | |
158 | rc = cap_ptrace_access_check(ctp, mode); |
159 | if (rc != 0) |
160 | return rc; |
161 | |
162 | tsp = smk_of_task(task_security(ctp)); |
163 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
164 | smk_ad_setfield_u_tsk(&ad, ctp); |
165 | |
166 | rc = smk_curacc(tsp, MAY_READWRITE, &ad); |
167 | return rc; |
168 | } |
169 | |
170 | /** |
171 | * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME |
172 | * @ptp: parent task pointer |
173 | * |
174 | * Returns 0 if access is OK, an error code otherwise |
175 | * |
176 | * Do the capability checks, and require read and write. |
177 | */ |
178 | static int smack_ptrace_traceme(struct task_struct *ptp) |
179 | { |
180 | int rc; |
181 | struct smk_audit_info ad; |
182 | char *tsp; |
183 | |
184 | rc = cap_ptrace_traceme(ptp); |
185 | if (rc != 0) |
186 | return rc; |
187 | |
188 | tsp = smk_of_task(task_security(ptp)); |
189 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
190 | smk_ad_setfield_u_tsk(&ad, ptp); |
191 | |
192 | rc = smk_curacc(tsp, MAY_READWRITE, &ad); |
193 | return rc; |
194 | } |
195 | |
196 | /** |
197 | * smack_syslog - Smack approval on syslog |
198 | * @type: message type |
199 | * |
200 | * Require that the task has the floor label |
201 | * |
202 | * Returns 0 on success, error code otherwise. |
203 | */ |
204 | static int smack_syslog(int typefrom_file) |
205 | { |
206 | int rc = 0; |
207 | char *sp = smk_of_current(); |
208 | |
209 | if (capable(CAP_MAC_OVERRIDE)) |
210 | return 0; |
211 | |
212 | if (sp != smack_known_floor.smk_known) |
213 | rc = -EACCES; |
214 | |
215 | return rc; |
216 | } |
217 | |
218 | |
219 | /* |
220 | * Superblock Hooks. |
221 | */ |
222 | |
223 | /** |
224 | * smack_sb_alloc_security - allocate a superblock blob |
225 | * @sb: the superblock getting the blob |
226 | * |
227 | * Returns 0 on success or -ENOMEM on error. |
228 | */ |
229 | static int smack_sb_alloc_security(struct super_block *sb) |
230 | { |
231 | struct superblock_smack *sbsp; |
232 | |
233 | sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL); |
234 | |
235 | if (sbsp == NULL) |
236 | return -ENOMEM; |
237 | |
238 | sbsp->smk_root = smack_known_floor.smk_known; |
239 | sbsp->smk_default = smack_known_floor.smk_known; |
240 | sbsp->smk_floor = smack_known_floor.smk_known; |
241 | sbsp->smk_hat = smack_known_hat.smk_known; |
242 | sbsp->smk_initialized = 0; |
243 | spin_lock_init(&sbsp->smk_sblock); |
244 | |
245 | sb->s_security = sbsp; |
246 | |
247 | return 0; |
248 | } |
249 | |
250 | /** |
251 | * smack_sb_free_security - free a superblock blob |
252 | * @sb: the superblock getting the blob |
253 | * |
254 | */ |
255 | static void smack_sb_free_security(struct super_block *sb) |
256 | { |
257 | kfree(sb->s_security); |
258 | sb->s_security = NULL; |
259 | } |
260 | |
261 | /** |
262 | * smack_sb_copy_data - copy mount options data for processing |
263 | * @orig: where to start |
264 | * @smackopts: mount options string |
265 | * |
266 | * Returns 0 on success or -ENOMEM on error. |
267 | * |
268 | * Copy the Smack specific mount options out of the mount |
269 | * options list. |
270 | */ |
271 | static int smack_sb_copy_data(char *orig, char *smackopts) |
272 | { |
273 | char *cp, *commap, *otheropts, *dp; |
274 | |
275 | otheropts = (char *)get_zeroed_page(GFP_KERNEL); |
276 | if (otheropts == NULL) |
277 | return -ENOMEM; |
278 | |
279 | for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) { |
280 | if (strstr(cp, SMK_FSDEFAULT) == cp) |
281 | dp = smackopts; |
282 | else if (strstr(cp, SMK_FSFLOOR) == cp) |
283 | dp = smackopts; |
284 | else if (strstr(cp, SMK_FSHAT) == cp) |
285 | dp = smackopts; |
286 | else if (strstr(cp, SMK_FSROOT) == cp) |
287 | dp = smackopts; |
288 | else |
289 | dp = otheropts; |
290 | |
291 | commap = strchr(cp, ','); |
292 | if (commap != NULL) |
293 | *commap = '\0'; |
294 | |
295 | if (*dp != '\0') |
296 | strcat(dp, ","); |
297 | strcat(dp, cp); |
298 | } |
299 | |
300 | strcpy(orig, otheropts); |
301 | free_page((unsigned long)otheropts); |
302 | |
303 | return 0; |
304 | } |
305 | |
306 | /** |
307 | * smack_sb_kern_mount - Smack specific mount processing |
308 | * @sb: the file system superblock |
309 | * @flags: the mount flags |
310 | * @data: the smack mount options |
311 | * |
312 | * Returns 0 on success, an error code on failure |
313 | */ |
314 | static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) |
315 | { |
316 | struct dentry *root = sb->s_root; |
317 | struct inode *inode = root->d_inode; |
318 | struct superblock_smack *sp = sb->s_security; |
319 | struct inode_smack *isp; |
320 | char *op; |
321 | char *commap; |
322 | char *nsp; |
323 | |
324 | spin_lock(&sp->smk_sblock); |
325 | if (sp->smk_initialized != 0) { |
326 | spin_unlock(&sp->smk_sblock); |
327 | return 0; |
328 | } |
329 | sp->smk_initialized = 1; |
330 | spin_unlock(&sp->smk_sblock); |
331 | |
332 | for (op = data; op != NULL; op = commap) { |
333 | commap = strchr(op, ','); |
334 | if (commap != NULL) |
335 | *commap++ = '\0'; |
336 | |
337 | if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) { |
338 | op += strlen(SMK_FSHAT); |
339 | nsp = smk_import(op, 0); |
340 | if (nsp != NULL) |
341 | sp->smk_hat = nsp; |
342 | } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) { |
343 | op += strlen(SMK_FSFLOOR); |
344 | nsp = smk_import(op, 0); |
345 | if (nsp != NULL) |
346 | sp->smk_floor = nsp; |
347 | } else if (strncmp(op, SMK_FSDEFAULT, |
348 | strlen(SMK_FSDEFAULT)) == 0) { |
349 | op += strlen(SMK_FSDEFAULT); |
350 | nsp = smk_import(op, 0); |
351 | if (nsp != NULL) |
352 | sp->smk_default = nsp; |
353 | } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) { |
354 | op += strlen(SMK_FSROOT); |
355 | nsp = smk_import(op, 0); |
356 | if (nsp != NULL) |
357 | sp->smk_root = nsp; |
358 | } |
359 | } |
360 | |
361 | /* |
362 | * Initialize the root inode. |
363 | */ |
364 | isp = inode->i_security; |
365 | if (isp == NULL) |
366 | inode->i_security = new_inode_smack(sp->smk_root); |
367 | else |
368 | isp->smk_inode = sp->smk_root; |
369 | |
370 | return 0; |
371 | } |
372 | |
373 | /** |
374 | * smack_sb_statfs - Smack check on statfs |
375 | * @dentry: identifies the file system in question |
376 | * |
377 | * Returns 0 if current can read the floor of the filesystem, |
378 | * and error code otherwise |
379 | */ |
380 | static int smack_sb_statfs(struct dentry *dentry) |
381 | { |
382 | struct superblock_smack *sbp = dentry->d_sb->s_security; |
383 | int rc; |
384 | struct smk_audit_info ad; |
385 | |
386 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
387 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
388 | |
389 | rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); |
390 | return rc; |
391 | } |
392 | |
393 | /** |
394 | * smack_sb_mount - Smack check for mounting |
395 | * @dev_name: unused |
396 | * @path: mount point |
397 | * @type: unused |
398 | * @flags: unused |
399 | * @data: unused |
400 | * |
401 | * Returns 0 if current can write the floor of the filesystem |
402 | * being mounted on, an error code otherwise. |
403 | */ |
404 | static int smack_sb_mount(char *dev_name, struct path *path, |
405 | char *type, unsigned long flags, void *data) |
406 | { |
407 | struct superblock_smack *sbp = path->mnt->mnt_sb->s_security; |
408 | struct smk_audit_info ad; |
409 | |
410 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
411 | smk_ad_setfield_u_fs_path(&ad, *path); |
412 | |
413 | return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); |
414 | } |
415 | |
416 | /** |
417 | * smack_sb_umount - Smack check for unmounting |
418 | * @mnt: file system to unmount |
419 | * @flags: unused |
420 | * |
421 | * Returns 0 if current can write the floor of the filesystem |
422 | * being unmounted, an error code otherwise. |
423 | */ |
424 | static int smack_sb_umount(struct vfsmount *mnt, int flags) |
425 | { |
426 | struct superblock_smack *sbp; |
427 | struct smk_audit_info ad; |
428 | struct path path; |
429 | |
430 | path.dentry = mnt->mnt_root; |
431 | path.mnt = mnt; |
432 | |
433 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
434 | smk_ad_setfield_u_fs_path(&ad, path); |
435 | |
436 | sbp = mnt->mnt_sb->s_security; |
437 | return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad); |
438 | } |
439 | |
440 | /* |
441 | * BPRM hooks |
442 | */ |
443 | |
444 | static int smack_bprm_set_creds(struct linux_binprm *bprm) |
445 | { |
446 | struct task_smack *tsp = bprm->cred->security; |
447 | struct inode_smack *isp; |
448 | struct dentry *dp; |
449 | int rc; |
450 | |
451 | rc = cap_bprm_set_creds(bprm); |
452 | if (rc != 0) |
453 | return rc; |
454 | |
455 | if (bprm->cred_prepared) |
456 | return 0; |
457 | |
458 | if (bprm->file == NULL || bprm->file->f_dentry == NULL) |
459 | return 0; |
460 | |
461 | dp = bprm->file->f_dentry; |
462 | |
463 | if (dp->d_inode == NULL) |
464 | return 0; |
465 | |
466 | isp = dp->d_inode->i_security; |
467 | |
468 | if (isp->smk_task != NULL) |
469 | tsp->smk_task = isp->smk_task; |
470 | |
471 | return 0; |
472 | } |
473 | |
474 | /* |
475 | * Inode hooks |
476 | */ |
477 | |
478 | /** |
479 | * smack_inode_alloc_security - allocate an inode blob |
480 | * @inode: the inode in need of a blob |
481 | * |
482 | * Returns 0 if it gets a blob, -ENOMEM otherwise |
483 | */ |
484 | static int smack_inode_alloc_security(struct inode *inode) |
485 | { |
486 | inode->i_security = new_inode_smack(smk_of_current()); |
487 | if (inode->i_security == NULL) |
488 | return -ENOMEM; |
489 | return 0; |
490 | } |
491 | |
492 | /** |
493 | * smack_inode_free_security - free an inode blob |
494 | * @inode: the inode with a blob |
495 | * |
496 | * Clears the blob pointer in inode |
497 | */ |
498 | static void smack_inode_free_security(struct inode *inode) |
499 | { |
500 | kfree(inode->i_security); |
501 | inode->i_security = NULL; |
502 | } |
503 | |
504 | /** |
505 | * smack_inode_init_security - copy out the smack from an inode |
506 | * @inode: the inode |
507 | * @dir: unused |
508 | * @qstr: unused |
509 | * @name: where to put the attribute name |
510 | * @value: where to put the attribute value |
511 | * @len: where to put the length of the attribute |
512 | * |
513 | * Returns 0 if it all works out, -ENOMEM if there's no memory |
514 | */ |
515 | static int smack_inode_init_security(struct inode *inode, struct inode *dir, |
516 | const struct qstr *qstr, char **name, |
517 | void **value, size_t *len) |
518 | { |
519 | char *isp = smk_of_inode(inode); |
520 | char *dsp = smk_of_inode(dir); |
521 | int may; |
522 | |
523 | if (name) { |
524 | *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); |
525 | if (*name == NULL) |
526 | return -ENOMEM; |
527 | } |
528 | |
529 | if (value) { |
530 | rcu_read_lock(); |
531 | may = smk_access_entry(smk_of_current(), dsp, &smack_rule_list); |
532 | rcu_read_unlock(); |
533 | |
534 | /* |
535 | * If the access rule allows transmutation and |
536 | * the directory requests transmutation then |
537 | * by all means transmute. |
538 | */ |
539 | if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && |
540 | smk_inode_transmutable(dir)) |
541 | isp = dsp; |
542 | |
543 | *value = kstrdup(isp, GFP_KERNEL); |
544 | if (*value == NULL) |
545 | return -ENOMEM; |
546 | } |
547 | |
548 | if (len) |
549 | *len = strlen(isp) + 1; |
550 | |
551 | return 0; |
552 | } |
553 | |
554 | /** |
555 | * smack_inode_link - Smack check on link |
556 | * @old_dentry: the existing object |
557 | * @dir: unused |
558 | * @new_dentry: the new object |
559 | * |
560 | * Returns 0 if access is permitted, an error code otherwise |
561 | */ |
562 | static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, |
563 | struct dentry *new_dentry) |
564 | { |
565 | char *isp; |
566 | struct smk_audit_info ad; |
567 | int rc; |
568 | |
569 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
570 | smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); |
571 | |
572 | isp = smk_of_inode(old_dentry->d_inode); |
573 | rc = smk_curacc(isp, MAY_WRITE, &ad); |
574 | |
575 | if (rc == 0 && new_dentry->d_inode != NULL) { |
576 | isp = smk_of_inode(new_dentry->d_inode); |
577 | smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); |
578 | rc = smk_curacc(isp, MAY_WRITE, &ad); |
579 | } |
580 | |
581 | return rc; |
582 | } |
583 | |
584 | /** |
585 | * smack_inode_unlink - Smack check on inode deletion |
586 | * @dir: containing directory object |
587 | * @dentry: file to unlink |
588 | * |
589 | * Returns 0 if current can write the containing directory |
590 | * and the object, error code otherwise |
591 | */ |
592 | static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) |
593 | { |
594 | struct inode *ip = dentry->d_inode; |
595 | struct smk_audit_info ad; |
596 | int rc; |
597 | |
598 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
599 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
600 | |
601 | /* |
602 | * You need write access to the thing you're unlinking |
603 | */ |
604 | rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); |
605 | if (rc == 0) { |
606 | /* |
607 | * You also need write access to the containing directory |
608 | */ |
609 | smk_ad_setfield_u_fs_path_dentry(&ad, NULL); |
610 | smk_ad_setfield_u_fs_inode(&ad, dir); |
611 | rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); |
612 | } |
613 | return rc; |
614 | } |
615 | |
616 | /** |
617 | * smack_inode_rmdir - Smack check on directory deletion |
618 | * @dir: containing directory object |
619 | * @dentry: directory to unlink |
620 | * |
621 | * Returns 0 if current can write the containing directory |
622 | * and the directory, error code otherwise |
623 | */ |
624 | static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) |
625 | { |
626 | struct smk_audit_info ad; |
627 | int rc; |
628 | |
629 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
630 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
631 | |
632 | /* |
633 | * You need write access to the thing you're removing |
634 | */ |
635 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); |
636 | if (rc == 0) { |
637 | /* |
638 | * You also need write access to the containing directory |
639 | */ |
640 | smk_ad_setfield_u_fs_path_dentry(&ad, NULL); |
641 | smk_ad_setfield_u_fs_inode(&ad, dir); |
642 | rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); |
643 | } |
644 | |
645 | return rc; |
646 | } |
647 | |
648 | /** |
649 | * smack_inode_rename - Smack check on rename |
650 | * @old_inode: the old directory |
651 | * @old_dentry: unused |
652 | * @new_inode: the new directory |
653 | * @new_dentry: unused |
654 | * |
655 | * Read and write access is required on both the old and |
656 | * new directories. |
657 | * |
658 | * Returns 0 if access is permitted, an error code otherwise |
659 | */ |
660 | static int smack_inode_rename(struct inode *old_inode, |
661 | struct dentry *old_dentry, |
662 | struct inode *new_inode, |
663 | struct dentry *new_dentry) |
664 | { |
665 | int rc; |
666 | char *isp; |
667 | struct smk_audit_info ad; |
668 | |
669 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
670 | smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); |
671 | |
672 | isp = smk_of_inode(old_dentry->d_inode); |
673 | rc = smk_curacc(isp, MAY_READWRITE, &ad); |
674 | |
675 | if (rc == 0 && new_dentry->d_inode != NULL) { |
676 | isp = smk_of_inode(new_dentry->d_inode); |
677 | smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); |
678 | rc = smk_curacc(isp, MAY_READWRITE, &ad); |
679 | } |
680 | return rc; |
681 | } |
682 | |
683 | /** |
684 | * smack_inode_permission - Smack version of permission() |
685 | * @inode: the inode in question |
686 | * @mask: the access requested |
687 | * |
688 | * This is the important Smack hook. |
689 | * |
690 | * Returns 0 if access is permitted, -EACCES otherwise |
691 | */ |
692 | static int smack_inode_permission(struct inode *inode, int mask, unsigned flags) |
693 | { |
694 | struct smk_audit_info ad; |
695 | |
696 | mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); |
697 | /* |
698 | * No permission to check. Existence test. Yup, it's there. |
699 | */ |
700 | if (mask == 0) |
701 | return 0; |
702 | |
703 | /* May be droppable after audit */ |
704 | if (flags & IPERM_FLAG_RCU) |
705 | return -ECHILD; |
706 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); |
707 | smk_ad_setfield_u_fs_inode(&ad, inode); |
708 | return smk_curacc(smk_of_inode(inode), mask, &ad); |
709 | } |
710 | |
711 | /** |
712 | * smack_inode_setattr - Smack check for setting attributes |
713 | * @dentry: the object |
714 | * @iattr: for the force flag |
715 | * |
716 | * Returns 0 if access is permitted, an error code otherwise |
717 | */ |
718 | static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) |
719 | { |
720 | struct smk_audit_info ad; |
721 | /* |
722 | * Need to allow for clearing the setuid bit. |
723 | */ |
724 | if (iattr->ia_valid & ATTR_FORCE) |
725 | return 0; |
726 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
727 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
728 | |
729 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); |
730 | } |
731 | |
732 | /** |
733 | * smack_inode_getattr - Smack check for getting attributes |
734 | * @mnt: unused |
735 | * @dentry: the object |
736 | * |
737 | * Returns 0 if access is permitted, an error code otherwise |
738 | */ |
739 | static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) |
740 | { |
741 | struct smk_audit_info ad; |
742 | struct path path; |
743 | |
744 | path.dentry = dentry; |
745 | path.mnt = mnt; |
746 | |
747 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
748 | smk_ad_setfield_u_fs_path(&ad, path); |
749 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); |
750 | } |
751 | |
752 | /** |
753 | * smack_inode_setxattr - Smack check for setting xattrs |
754 | * @dentry: the object |
755 | * @name: name of the attribute |
756 | * @value: unused |
757 | * @size: unused |
758 | * @flags: unused |
759 | * |
760 | * This protects the Smack attribute explicitly. |
761 | * |
762 | * Returns 0 if access is permitted, an error code otherwise |
763 | */ |
764 | static int smack_inode_setxattr(struct dentry *dentry, const char *name, |
765 | const void *value, size_t size, int flags) |
766 | { |
767 | struct smk_audit_info ad; |
768 | int rc = 0; |
769 | |
770 | if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
771 | strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || |
772 | strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || |
773 | strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || |
774 | strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { |
775 | if (!capable(CAP_MAC_ADMIN)) |
776 | rc = -EPERM; |
777 | /* |
778 | * check label validity here so import wont fail on |
779 | * post_setxattr |
780 | */ |
781 | if (size == 0 || size >= SMK_LABELLEN || |
782 | smk_import(value, size) == NULL) |
783 | rc = -EINVAL; |
784 | } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { |
785 | if (!capable(CAP_MAC_ADMIN)) |
786 | rc = -EPERM; |
787 | if (size != TRANS_TRUE_SIZE || |
788 | strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0) |
789 | rc = -EINVAL; |
790 | } else |
791 | rc = cap_inode_setxattr(dentry, name, value, size, flags); |
792 | |
793 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
794 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
795 | |
796 | if (rc == 0) |
797 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); |
798 | |
799 | return rc; |
800 | } |
801 | |
802 | /** |
803 | * smack_inode_post_setxattr - Apply the Smack update approved above |
804 | * @dentry: object |
805 | * @name: attribute name |
806 | * @value: attribute value |
807 | * @size: attribute size |
808 | * @flags: unused |
809 | * |
810 | * Set the pointer in the inode blob to the entry found |
811 | * in the master label list. |
812 | */ |
813 | static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, |
814 | const void *value, size_t size, int flags) |
815 | { |
816 | char *nsp; |
817 | struct inode_smack *isp = dentry->d_inode->i_security; |
818 | |
819 | if (strcmp(name, XATTR_NAME_SMACK) == 0) { |
820 | nsp = smk_import(value, size); |
821 | if (nsp != NULL) |
822 | isp->smk_inode = nsp; |
823 | else |
824 | isp->smk_inode = smack_known_invalid.smk_known; |
825 | } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) { |
826 | nsp = smk_import(value, size); |
827 | if (nsp != NULL) |
828 | isp->smk_task = nsp; |
829 | else |
830 | isp->smk_task = smack_known_invalid.smk_known; |
831 | } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { |
832 | nsp = smk_import(value, size); |
833 | if (nsp != NULL) |
834 | isp->smk_mmap = nsp; |
835 | else |
836 | isp->smk_mmap = smack_known_invalid.smk_known; |
837 | } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) |
838 | isp->smk_flags |= SMK_INODE_TRANSMUTE; |
839 | |
840 | return; |
841 | } |
842 | |
843 | /* |
844 | * smack_inode_getxattr - Smack check on getxattr |
845 | * @dentry: the object |
846 | * @name: unused |
847 | * |
848 | * Returns 0 if access is permitted, an error code otherwise |
849 | */ |
850 | static int smack_inode_getxattr(struct dentry *dentry, const char *name) |
851 | { |
852 | struct smk_audit_info ad; |
853 | |
854 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
855 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
856 | |
857 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); |
858 | } |
859 | |
860 | /* |
861 | * smack_inode_removexattr - Smack check on removexattr |
862 | * @dentry: the object |
863 | * @name: name of the attribute |
864 | * |
865 | * Removing the Smack attribute requires CAP_MAC_ADMIN |
866 | * |
867 | * Returns 0 if access is permitted, an error code otherwise |
868 | */ |
869 | static int smack_inode_removexattr(struct dentry *dentry, const char *name) |
870 | { |
871 | struct inode_smack *isp; |
872 | struct smk_audit_info ad; |
873 | int rc = 0; |
874 | |
875 | if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
876 | strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || |
877 | strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || |
878 | strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || |
879 | strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 || |
880 | strcmp(name, XATTR_NAME_SMACKMMAP)) { |
881 | if (!capable(CAP_MAC_ADMIN)) |
882 | rc = -EPERM; |
883 | } else |
884 | rc = cap_inode_removexattr(dentry, name); |
885 | |
886 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); |
887 | smk_ad_setfield_u_fs_path_dentry(&ad, dentry); |
888 | if (rc == 0) |
889 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); |
890 | |
891 | if (rc == 0) { |
892 | isp = dentry->d_inode->i_security; |
893 | isp->smk_task = NULL; |
894 | isp->smk_mmap = NULL; |
895 | } |
896 | |
897 | return rc; |
898 | } |
899 | |
900 | /** |
901 | * smack_inode_getsecurity - get smack xattrs |
902 | * @inode: the object |
903 | * @name: attribute name |
904 | * @buffer: where to put the result |
905 | * @alloc: unused |
906 | * |
907 | * Returns the size of the attribute or an error code |
908 | */ |
909 | static int smack_inode_getsecurity(const struct inode *inode, |
910 | const char *name, void **buffer, |
911 | bool alloc) |
912 | { |
913 | struct socket_smack *ssp; |
914 | struct socket *sock; |
915 | struct super_block *sbp; |
916 | struct inode *ip = (struct inode *)inode; |
917 | char *isp; |
918 | int ilen; |
919 | int rc = 0; |
920 | |
921 | if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { |
922 | isp = smk_of_inode(inode); |
923 | ilen = strlen(isp) + 1; |
924 | *buffer = isp; |
925 | return ilen; |
926 | } |
927 | |
928 | /* |
929 | * The rest of the Smack xattrs are only on sockets. |
930 | */ |
931 | sbp = ip->i_sb; |
932 | if (sbp->s_magic != SOCKFS_MAGIC) |
933 | return -EOPNOTSUPP; |
934 | |
935 | sock = SOCKET_I(ip); |
936 | if (sock == NULL || sock->sk == NULL) |
937 | return -EOPNOTSUPP; |
938 | |
939 | ssp = sock->sk->sk_security; |
940 | |
941 | if (strcmp(name, XATTR_SMACK_IPIN) == 0) |
942 | isp = ssp->smk_in; |
943 | else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) |
944 | isp = ssp->smk_out; |
945 | else |
946 | return -EOPNOTSUPP; |
947 | |
948 | ilen = strlen(isp) + 1; |
949 | if (rc == 0) { |
950 | *buffer = isp; |
951 | rc = ilen; |
952 | } |
953 | |
954 | return rc; |
955 | } |
956 | |
957 | |
958 | /** |
959 | * smack_inode_listsecurity - list the Smack attributes |
960 | * @inode: the object |
961 | * @buffer: where they go |
962 | * @buffer_size: size of buffer |
963 | * |
964 | * Returns 0 on success, -EINVAL otherwise |
965 | */ |
966 | static int smack_inode_listsecurity(struct inode *inode, char *buffer, |
967 | size_t buffer_size) |
968 | { |
969 | int len = strlen(XATTR_NAME_SMACK); |
970 | |
971 | if (buffer != NULL && len <= buffer_size) { |
972 | memcpy(buffer, XATTR_NAME_SMACK, len); |
973 | return len; |
974 | } |
975 | return -EINVAL; |
976 | } |
977 | |
978 | /** |
979 | * smack_inode_getsecid - Extract inode's security id |
980 | * @inode: inode to extract the info from |
981 | * @secid: where result will be saved |
982 | */ |
983 | static void smack_inode_getsecid(const struct inode *inode, u32 *secid) |
984 | { |
985 | struct inode_smack *isp = inode->i_security; |
986 | |
987 | *secid = smack_to_secid(isp->smk_inode); |
988 | } |
989 | |
990 | /* |
991 | * File Hooks |
992 | */ |
993 | |
994 | /** |
995 | * smack_file_permission - Smack check on file operations |
996 | * @file: unused |
997 | * @mask: unused |
998 | * |
999 | * Returns 0 |
1000 | * |
1001 | * Should access checks be done on each read or write? |
1002 | * UNICOS and SELinux say yes. |
1003 | * Trusted Solaris, Trusted Irix, and just about everyone else says no. |
1004 | * |
1005 | * I'll say no for now. Smack does not do the frequent |
1006 | * label changing that SELinux does. |
1007 | */ |
1008 | static int smack_file_permission(struct file *file, int mask) |
1009 | { |
1010 | return 0; |
1011 | } |
1012 | |
1013 | /** |
1014 | * smack_file_alloc_security - assign a file security blob |
1015 | * @file: the object |
1016 | * |
1017 | * The security blob for a file is a pointer to the master |
1018 | * label list, so no allocation is done. |
1019 | * |
1020 | * Returns 0 |
1021 | */ |
1022 | static int smack_file_alloc_security(struct file *file) |
1023 | { |
1024 | file->f_security = smk_of_current(); |
1025 | return 0; |
1026 | } |
1027 | |
1028 | /** |
1029 | * smack_file_free_security - clear a file security blob |
1030 | * @file: the object |
1031 | * |
1032 | * The security blob for a file is a pointer to the master |
1033 | * label list, so no memory is freed. |
1034 | */ |
1035 | static void smack_file_free_security(struct file *file) |
1036 | { |
1037 | file->f_security = NULL; |
1038 | } |
1039 | |
1040 | /** |
1041 | * smack_file_ioctl - Smack check on ioctls |
1042 | * @file: the object |
1043 | * @cmd: what to do |
1044 | * @arg: unused |
1045 | * |
1046 | * Relies heavily on the correct use of the ioctl command conventions. |
1047 | * |
1048 | * Returns 0 if allowed, error code otherwise |
1049 | */ |
1050 | static int smack_file_ioctl(struct file *file, unsigned int cmd, |
1051 | unsigned long arg) |
1052 | { |
1053 | int rc = 0; |
1054 | struct smk_audit_info ad; |
1055 | |
1056 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
1057 | smk_ad_setfield_u_fs_path(&ad, file->f_path); |
1058 | |
1059 | if (_IOC_DIR(cmd) & _IOC_WRITE) |
1060 | rc = smk_curacc(file->f_security, MAY_WRITE, &ad); |
1061 | |
1062 | if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) |
1063 | rc = smk_curacc(file->f_security, MAY_READ, &ad); |
1064 | |
1065 | return rc; |
1066 | } |
1067 | |
1068 | /** |
1069 | * smack_file_lock - Smack check on file locking |
1070 | * @file: the object |
1071 | * @cmd: unused |
1072 | * |
1073 | * Returns 0 if current has write access, error code otherwise |
1074 | */ |
1075 | static int smack_file_lock(struct file *file, unsigned int cmd) |
1076 | { |
1077 | struct smk_audit_info ad; |
1078 | |
1079 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
1080 | smk_ad_setfield_u_fs_path(&ad, file->f_path); |
1081 | return smk_curacc(file->f_security, MAY_WRITE, &ad); |
1082 | } |
1083 | |
1084 | /** |
1085 | * smack_file_fcntl - Smack check on fcntl |
1086 | * @file: the object |
1087 | * @cmd: what action to check |
1088 | * @arg: unused |
1089 | * |
1090 | * Returns 0 if current has access, error code otherwise |
1091 | */ |
1092 | static int smack_file_fcntl(struct file *file, unsigned int cmd, |
1093 | unsigned long arg) |
1094 | { |
1095 | struct smk_audit_info ad; |
1096 | int rc; |
1097 | |
1098 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); |
1099 | smk_ad_setfield_u_fs_path(&ad, file->f_path); |
1100 | |
1101 | switch (cmd) { |
1102 | case F_DUPFD: |
1103 | case F_GETFD: |
1104 | case F_GETFL: |
1105 | case F_GETLK: |
1106 | case F_GETOWN: |
1107 | case F_GETSIG: |
1108 | rc = smk_curacc(file->f_security, MAY_READ, &ad); |
1109 | break; |
1110 | case F_SETFD: |
1111 | case F_SETFL: |
1112 | case F_SETLK: |
1113 | case F_SETLKW: |
1114 | case F_SETOWN: |
1115 | case F_SETSIG: |
1116 | rc = smk_curacc(file->f_security, MAY_WRITE, &ad); |
1117 | break; |
1118 | default: |
1119 | rc = smk_curacc(file->f_security, MAY_READWRITE, &ad); |
1120 | } |
1121 | |
1122 | return rc; |
1123 | } |
1124 | |
1125 | /** |
1126 | * smack_file_mmap : |
1127 | * Check permissions for a mmap operation. The @file may be NULL, e.g. |
1128 | * if mapping anonymous memory. |
1129 | * @file contains the file structure for file to map (may be NULL). |
1130 | * @reqprot contains the protection requested by the application. |
1131 | * @prot contains the protection that will be applied by the kernel. |
1132 | * @flags contains the operational flags. |
1133 | * Return 0 if permission is granted. |
1134 | */ |
1135 | static int smack_file_mmap(struct file *file, |
1136 | unsigned long reqprot, unsigned long prot, |
1137 | unsigned long flags, unsigned long addr, |
1138 | unsigned long addr_only) |
1139 | { |
1140 | struct smack_rule *srp; |
1141 | struct task_smack *tsp; |
1142 | char *sp; |
1143 | char *msmack; |
1144 | char *osmack; |
1145 | struct inode_smack *isp; |
1146 | struct dentry *dp; |
1147 | int may; |
1148 | int mmay; |
1149 | int tmay; |
1150 | int rc; |
1151 | |
1152 | /* do DAC check on address space usage */ |
1153 | rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); |
1154 | if (rc || addr_only) |
1155 | return rc; |
1156 | |
1157 | if (file == NULL || file->f_dentry == NULL) |
1158 | return 0; |
1159 | |
1160 | dp = file->f_dentry; |
1161 | |
1162 | if (dp->d_inode == NULL) |
1163 | return 0; |
1164 | |
1165 | isp = dp->d_inode->i_security; |
1166 | if (isp->smk_mmap == NULL) |
1167 | return 0; |
1168 | msmack = isp->smk_mmap; |
1169 | |
1170 | tsp = current_security(); |
1171 | sp = smk_of_current(); |
1172 | rc = 0; |
1173 | |
1174 | rcu_read_lock(); |
1175 | /* |
1176 | * For each Smack rule associated with the subject |
1177 | * label verify that the SMACK64MMAP also has access |
1178 | * to that rule's object label. |
1179 | * |
1180 | * Because neither of the labels comes |
1181 | * from the networking code it is sufficient |
1182 | * to compare pointers. |
1183 | */ |
1184 | list_for_each_entry_rcu(srp, &smack_rule_list, list) { |
1185 | if (srp->smk_subject != sp) |
1186 | continue; |
1187 | |
1188 | osmack = srp->smk_object; |
1189 | /* |
1190 | * Matching labels always allows access. |
1191 | */ |
1192 | if (msmack == osmack) |
1193 | continue; |
1194 | /* |
1195 | * If there is a matching local rule take |
1196 | * that into account as well. |
1197 | */ |
1198 | may = smk_access_entry(srp->smk_subject, osmack, |
1199 | &tsp->smk_rules); |
1200 | if (may == -ENOENT) |
1201 | may = srp->smk_access; |
1202 | else |
1203 | may &= srp->smk_access; |
1204 | /* |
1205 | * If may is zero the SMACK64MMAP subject can't |
1206 | * possibly have less access. |
1207 | */ |
1208 | if (may == 0) |
1209 | continue; |
1210 | |
1211 | /* |
1212 | * Fetch the global list entry. |
1213 | * If there isn't one a SMACK64MMAP subject |
1214 | * can't have as much access as current. |
1215 | */ |
1216 | mmay = smk_access_entry(msmack, osmack, &smack_rule_list); |
1217 | if (mmay == -ENOENT) { |
1218 | rc = -EACCES; |
1219 | break; |
1220 | } |
1221 | /* |
1222 | * If there is a local entry it modifies the |
1223 | * potential access, too. |
1224 | */ |
1225 | tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules); |
1226 | if (tmay != -ENOENT) |
1227 | mmay &= tmay; |
1228 | |
1229 | /* |
1230 | * If there is any access available to current that is |
1231 | * not available to a SMACK64MMAP subject |
1232 | * deny access. |
1233 | */ |
1234 | if ((may | mmay) != mmay) { |
1235 | rc = -EACCES; |
1236 | break; |
1237 | } |
1238 | } |
1239 | |
1240 | rcu_read_unlock(); |
1241 | |
1242 | return rc; |
1243 | } |
1244 | |
1245 | /** |
1246 | * smack_file_set_fowner - set the file security blob value |
1247 | * @file: object in question |
1248 | * |
1249 | * Returns 0 |
1250 | * Further research may be required on this one. |
1251 | */ |
1252 | static int smack_file_set_fowner(struct file *file) |
1253 | { |
1254 | file->f_security = smk_of_current(); |
1255 | return 0; |
1256 | } |
1257 | |
1258 | /** |
1259 | * smack_file_send_sigiotask - Smack on sigio |
1260 | * @tsk: The target task |
1261 | * @fown: the object the signal come from |
1262 | * @signum: unused |
1263 | * |
1264 | * Allow a privileged task to get signals even if it shouldn't |
1265 | * |
1266 | * Returns 0 if a subject with the object's smack could |
1267 | * write to the task, an error code otherwise. |
1268 | */ |
1269 | static int smack_file_send_sigiotask(struct task_struct *tsk, |
1270 | struct fown_struct *fown, int signum) |
1271 | { |
1272 | struct file *file; |
1273 | int rc; |
1274 | char *tsp = smk_of_task(tsk->cred->security); |
1275 | struct smk_audit_info ad; |
1276 | |
1277 | /* |
1278 | * struct fown_struct is never outside the context of a struct file |
1279 | */ |
1280 | file = container_of(fown, struct file, f_owner); |
1281 | |
1282 | /* we don't log here as rc can be overriden */ |
1283 | rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL); |
1284 | if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) |
1285 | rc = 0; |
1286 | |
1287 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
1288 | smk_ad_setfield_u_tsk(&ad, tsk); |
1289 | smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad); |
1290 | return rc; |
1291 | } |
1292 | |
1293 | /** |
1294 | * smack_file_receive - Smack file receive check |
1295 | * @file: the object |
1296 | * |
1297 | * Returns 0 if current has access, error code otherwise |
1298 | */ |
1299 | static int smack_file_receive(struct file *file) |
1300 | { |
1301 | int may = 0; |
1302 | struct smk_audit_info ad; |
1303 | |
1304 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
1305 | smk_ad_setfield_u_fs_path(&ad, file->f_path); |
1306 | /* |
1307 | * This code relies on bitmasks. |
1308 | */ |
1309 | if (file->f_mode & FMODE_READ) |
1310 | may = MAY_READ; |
1311 | if (file->f_mode & FMODE_WRITE) |
1312 | may |= MAY_WRITE; |
1313 | |
1314 | return smk_curacc(file->f_security, may, &ad); |
1315 | } |
1316 | |
1317 | /* |
1318 | * Task hooks |
1319 | */ |
1320 | |
1321 | /** |
1322 | * smack_cred_alloc_blank - "allocate" blank task-level security credentials |
1323 | * @new: the new credentials |
1324 | * @gfp: the atomicity of any memory allocations |
1325 | * |
1326 | * Prepare a blank set of credentials for modification. This must allocate all |
1327 | * the memory the LSM module might require such that cred_transfer() can |
1328 | * complete without error. |
1329 | */ |
1330 | static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) |
1331 | { |
1332 | struct task_smack *tsp; |
1333 | |
1334 | tsp = new_task_smack(NULL, NULL, gfp); |
1335 | if (tsp == NULL) |
1336 | return -ENOMEM; |
1337 | |
1338 | cred->security = tsp; |
1339 | |
1340 | return 0; |
1341 | } |
1342 | |
1343 | |
1344 | /** |
1345 | * smack_cred_free - "free" task-level security credentials |
1346 | * @cred: the credentials in question |
1347 | * |
1348 | */ |
1349 | static void smack_cred_free(struct cred *cred) |
1350 | { |
1351 | struct task_smack *tsp = cred->security; |
1352 | struct smack_rule *rp; |
1353 | struct list_head *l; |
1354 | struct list_head *n; |
1355 | |
1356 | if (tsp == NULL) |
1357 | return; |
1358 | cred->security = NULL; |
1359 | |
1360 | list_for_each_safe(l, n, &tsp->smk_rules) { |
1361 | rp = list_entry(l, struct smack_rule, list); |
1362 | list_del(&rp->list); |
1363 | kfree(rp); |
1364 | } |
1365 | kfree(tsp); |
1366 | } |
1367 | |
1368 | /** |
1369 | * smack_cred_prepare - prepare new set of credentials for modification |
1370 | * @new: the new credentials |
1371 | * @old: the original credentials |
1372 | * @gfp: the atomicity of any memory allocations |
1373 | * |
1374 | * Prepare a new set of credentials for modification. |
1375 | */ |
1376 | static int smack_cred_prepare(struct cred *new, const struct cred *old, |
1377 | gfp_t gfp) |
1378 | { |
1379 | struct task_smack *old_tsp = old->security; |
1380 | struct task_smack *new_tsp; |
1381 | int rc; |
1382 | |
1383 | new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp); |
1384 | if (new_tsp == NULL) |
1385 | return -ENOMEM; |
1386 | |
1387 | rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp); |
1388 | if (rc != 0) |
1389 | return rc; |
1390 | |
1391 | new->security = new_tsp; |
1392 | return 0; |
1393 | } |
1394 | |
1395 | /** |
1396 | * smack_cred_transfer - Transfer the old credentials to the new credentials |
1397 | * @new: the new credentials |
1398 | * @old: the original credentials |
1399 | * |
1400 | * Fill in a set of blank credentials from another set of credentials. |
1401 | */ |
1402 | static void smack_cred_transfer(struct cred *new, const struct cred *old) |
1403 | { |
1404 | struct task_smack *old_tsp = old->security; |
1405 | struct task_smack *new_tsp = new->security; |
1406 | |
1407 | new_tsp->smk_task = old_tsp->smk_task; |
1408 | new_tsp->smk_forked = old_tsp->smk_task; |
1409 | mutex_init(&new_tsp->smk_rules_lock); |
1410 | INIT_LIST_HEAD(&new_tsp->smk_rules); |
1411 | |
1412 | |
1413 | /* cbs copy rule list */ |
1414 | } |
1415 | |
1416 | /** |
1417 | * smack_kernel_act_as - Set the subjective context in a set of credentials |
1418 | * @new: points to the set of credentials to be modified. |
1419 | * @secid: specifies the security ID to be set |
1420 | * |
1421 | * Set the security data for a kernel service. |
1422 | */ |
1423 | static int smack_kernel_act_as(struct cred *new, u32 secid) |
1424 | { |
1425 | struct task_smack *new_tsp = new->security; |
1426 | char *smack = smack_from_secid(secid); |
1427 | |
1428 | if (smack == NULL) |
1429 | return -EINVAL; |
1430 | |
1431 | new_tsp->smk_task = smack; |
1432 | return 0; |
1433 | } |
1434 | |
1435 | /** |
1436 | * smack_kernel_create_files_as - Set the file creation label in a set of creds |
1437 | * @new: points to the set of credentials to be modified |
1438 | * @inode: points to the inode to use as a reference |
1439 | * |
1440 | * Set the file creation context in a set of credentials to the same |
1441 | * as the objective context of the specified inode |
1442 | */ |
1443 | static int smack_kernel_create_files_as(struct cred *new, |
1444 | struct inode *inode) |
1445 | { |
1446 | struct inode_smack *isp = inode->i_security; |
1447 | struct task_smack *tsp = new->security; |
1448 | |
1449 | tsp->smk_forked = isp->smk_inode; |
1450 | tsp->smk_task = isp->smk_inode; |
1451 | return 0; |
1452 | } |
1453 | |
1454 | /** |
1455 | * smk_curacc_on_task - helper to log task related access |
1456 | * @p: the task object |
1457 | * @access : the access requested |
1458 | * |
1459 | * Return 0 if access is permitted |
1460 | */ |
1461 | static int smk_curacc_on_task(struct task_struct *p, int access) |
1462 | { |
1463 | struct smk_audit_info ad; |
1464 | |
1465 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
1466 | smk_ad_setfield_u_tsk(&ad, p); |
1467 | return smk_curacc(smk_of_task(task_security(p)), access, &ad); |
1468 | } |
1469 | |
1470 | /** |
1471 | * smack_task_setpgid - Smack check on setting pgid |
1472 | * @p: the task object |
1473 | * @pgid: unused |
1474 | * |
1475 | * Return 0 if write access is permitted |
1476 | */ |
1477 | static int smack_task_setpgid(struct task_struct *p, pid_t pgid) |
1478 | { |
1479 | return smk_curacc_on_task(p, MAY_WRITE); |
1480 | } |
1481 | |
1482 | /** |
1483 | * smack_task_getpgid - Smack access check for getpgid |
1484 | * @p: the object task |
1485 | * |
1486 | * Returns 0 if current can read the object task, error code otherwise |
1487 | */ |
1488 | static int smack_task_getpgid(struct task_struct *p) |
1489 | { |
1490 | return smk_curacc_on_task(p, MAY_READ); |
1491 | } |
1492 | |
1493 | /** |
1494 | * smack_task_getsid - Smack access check for getsid |
1495 | * @p: the object task |
1496 | * |
1497 | * Returns 0 if current can read the object task, error code otherwise |
1498 | */ |
1499 | static int smack_task_getsid(struct task_struct *p) |
1500 | { |
1501 | return smk_curacc_on_task(p, MAY_READ); |
1502 | } |
1503 | |
1504 | /** |
1505 | * smack_task_getsecid - get the secid of the task |
1506 | * @p: the object task |
1507 | * @secid: where to put the result |
1508 | * |
1509 | * Sets the secid to contain a u32 version of the smack label. |
1510 | */ |
1511 | static void smack_task_getsecid(struct task_struct *p, u32 *secid) |
1512 | { |
1513 | *secid = smack_to_secid(smk_of_task(task_security(p))); |
1514 | } |
1515 | |
1516 | /** |
1517 | * smack_task_setnice - Smack check on setting nice |
1518 | * @p: the task object |
1519 | * @nice: unused |
1520 | * |
1521 | * Return 0 if write access is permitted |
1522 | */ |
1523 | static int smack_task_setnice(struct task_struct *p, int nice) |
1524 | { |
1525 | int rc; |
1526 | |
1527 | rc = cap_task_setnice(p, nice); |
1528 | if (rc == 0) |
1529 | rc = smk_curacc_on_task(p, MAY_WRITE); |
1530 | return rc; |
1531 | } |
1532 | |
1533 | /** |
1534 | * smack_task_setioprio - Smack check on setting ioprio |
1535 | * @p: the task object |
1536 | * @ioprio: unused |
1537 | * |
1538 | * Return 0 if write access is permitted |
1539 | */ |
1540 | static int smack_task_setioprio(struct task_struct *p, int ioprio) |
1541 | { |
1542 | int rc; |
1543 | |
1544 | rc = cap_task_setioprio(p, ioprio); |
1545 | if (rc == 0) |
1546 | rc = smk_curacc_on_task(p, MAY_WRITE); |
1547 | return rc; |
1548 | } |
1549 | |
1550 | /** |
1551 | * smack_task_getioprio - Smack check on reading ioprio |
1552 | * @p: the task object |
1553 | * |
1554 | * Return 0 if read access is permitted |
1555 | */ |
1556 | static int smack_task_getioprio(struct task_struct *p) |
1557 | { |
1558 | return smk_curacc_on_task(p, MAY_READ); |
1559 | } |
1560 | |
1561 | /** |
1562 | * smack_task_setscheduler - Smack check on setting scheduler |
1563 | * @p: the task object |
1564 | * @policy: unused |
1565 | * @lp: unused |
1566 | * |
1567 | * Return 0 if read access is permitted |
1568 | */ |
1569 | static int smack_task_setscheduler(struct task_struct *p) |
1570 | { |
1571 | int rc; |
1572 | |
1573 | rc = cap_task_setscheduler(p); |
1574 | if (rc == 0) |
1575 | rc = smk_curacc_on_task(p, MAY_WRITE); |
1576 | return rc; |
1577 | } |
1578 | |
1579 | /** |
1580 | * smack_task_getscheduler - Smack check on reading scheduler |
1581 | * @p: the task object |
1582 | * |
1583 | * Return 0 if read access is permitted |
1584 | */ |
1585 | static int smack_task_getscheduler(struct task_struct *p) |
1586 | { |
1587 | return smk_curacc_on_task(p, MAY_READ); |
1588 | } |
1589 | |
1590 | /** |
1591 | * smack_task_movememory - Smack check on moving memory |
1592 | * @p: the task object |
1593 | * |
1594 | * Return 0 if write access is permitted |
1595 | */ |
1596 | static int smack_task_movememory(struct task_struct *p) |
1597 | { |
1598 | return smk_curacc_on_task(p, MAY_WRITE); |
1599 | } |
1600 | |
1601 | /** |
1602 | * smack_task_kill - Smack check on signal delivery |
1603 | * @p: the task object |
1604 | * @info: unused |
1605 | * @sig: unused |
1606 | * @secid: identifies the smack to use in lieu of current's |
1607 | * |
1608 | * Return 0 if write access is permitted |
1609 | * |
1610 | * The secid behavior is an artifact of an SELinux hack |
1611 | * in the USB code. Someday it may go away. |
1612 | */ |
1613 | static int smack_task_kill(struct task_struct *p, struct siginfo *info, |
1614 | int sig, u32 secid) |
1615 | { |
1616 | struct smk_audit_info ad; |
1617 | |
1618 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
1619 | smk_ad_setfield_u_tsk(&ad, p); |
1620 | /* |
1621 | * Sending a signal requires that the sender |
1622 | * can write the receiver. |
1623 | */ |
1624 | if (secid == 0) |
1625 | return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE, |
1626 | &ad); |
1627 | /* |
1628 | * If the secid isn't 0 we're dealing with some USB IO |
1629 | * specific behavior. This is not clean. For one thing |
1630 | * we can't take privilege into account. |
1631 | */ |
1632 | return smk_access(smack_from_secid(secid), |
1633 | smk_of_task(task_security(p)), MAY_WRITE, &ad); |
1634 | } |
1635 | |
1636 | /** |
1637 | * smack_task_wait - Smack access check for waiting |
1638 | * @p: task to wait for |
1639 | * |
1640 | * Returns 0 if current can wait for p, error code otherwise |
1641 | */ |
1642 | static int smack_task_wait(struct task_struct *p) |
1643 | { |
1644 | struct smk_audit_info ad; |
1645 | char *sp = smk_of_current(); |
1646 | char *tsp = smk_of_forked(task_security(p)); |
1647 | int rc; |
1648 | |
1649 | /* we don't log here, we can be overriden */ |
1650 | rc = smk_access(tsp, sp, MAY_WRITE, NULL); |
1651 | if (rc == 0) |
1652 | goto out_log; |
1653 | |
1654 | /* |
1655 | * Allow the operation to succeed if either task |
1656 | * has privilege to perform operations that might |
1657 | * account for the smack labels having gotten to |
1658 | * be different in the first place. |
1659 | * |
1660 | * This breaks the strict subject/object access |
1661 | * control ideal, taking the object's privilege |
1662 | * state into account in the decision as well as |
1663 | * the smack value. |
1664 | */ |
1665 | if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE)) |
1666 | rc = 0; |
1667 | /* we log only if we didn't get overriden */ |
1668 | out_log: |
1669 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); |
1670 | smk_ad_setfield_u_tsk(&ad, p); |
1671 | smack_log(tsp, sp, MAY_WRITE, rc, &ad); |
1672 | return rc; |
1673 | } |
1674 | |
1675 | /** |
1676 | * smack_task_to_inode - copy task smack into the inode blob |
1677 | * @p: task to copy from |
1678 | * @inode: inode to copy to |
1679 | * |
1680 | * Sets the smack pointer in the inode security blob |
1681 | */ |
1682 | static void smack_task_to_inode(struct task_struct *p, struct inode *inode) |
1683 | { |
1684 | struct inode_smack *isp = inode->i_security; |
1685 | isp->smk_inode = smk_of_task(task_security(p)); |
1686 | } |
1687 | |
1688 | /* |
1689 | * Socket hooks. |
1690 | */ |
1691 | |
1692 | /** |
1693 | * smack_sk_alloc_security - Allocate a socket blob |
1694 | * @sk: the socket |
1695 | * @family: unused |
1696 | * @gfp_flags: memory allocation flags |
1697 | * |
1698 | * Assign Smack pointers to current |
1699 | * |
1700 | * Returns 0 on success, -ENOMEM is there's no memory |
1701 | */ |
1702 | static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) |
1703 | { |
1704 | char *csp = smk_of_current(); |
1705 | struct socket_smack *ssp; |
1706 | |
1707 | ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); |
1708 | if (ssp == NULL) |
1709 | return -ENOMEM; |
1710 | |
1711 | ssp->smk_in = csp; |
1712 | ssp->smk_out = csp; |
1713 | ssp->smk_packet[0] = '\0'; |
1714 | |
1715 | sk->sk_security = ssp; |
1716 | |
1717 | return 0; |
1718 | } |
1719 | |
1720 | /** |
1721 | * smack_sk_free_security - Free a socket blob |
1722 | * @sk: the socket |
1723 | * |
1724 | * Clears the blob pointer |
1725 | */ |
1726 | static void smack_sk_free_security(struct sock *sk) |
1727 | { |
1728 | kfree(sk->sk_security); |
1729 | } |
1730 | |
1731 | /** |
1732 | * smack_host_label - check host based restrictions |
1733 | * @sip: the object end |
1734 | * |
1735 | * looks for host based access restrictions |
1736 | * |
1737 | * This version will only be appropriate for really small sets of single label |
1738 | * hosts. The caller is responsible for ensuring that the RCU read lock is |
1739 | * taken before calling this function. |
1740 | * |
1741 | * Returns the label of the far end or NULL if it's not special. |
1742 | */ |
1743 | static char *smack_host_label(struct sockaddr_in *sip) |
1744 | { |
1745 | struct smk_netlbladdr *snp; |
1746 | struct in_addr *siap = &sip->sin_addr; |
1747 | |
1748 | if (siap->s_addr == 0) |
1749 | return NULL; |
1750 | |
1751 | list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) |
1752 | /* |
1753 | * we break after finding the first match because |
1754 | * the list is sorted from longest to shortest mask |
1755 | * so we have found the most specific match |
1756 | */ |
1757 | if ((&snp->smk_host.sin_addr)->s_addr == |
1758 | (siap->s_addr & (&snp->smk_mask)->s_addr)) { |
1759 | /* we have found the special CIPSO option */ |
1760 | if (snp->smk_label == smack_cipso_option) |
1761 | return NULL; |
1762 | return snp->smk_label; |
1763 | } |
1764 | |
1765 | return NULL; |
1766 | } |
1767 | |
1768 | /** |
1769 | * smack_set_catset - convert a capset to netlabel mls categories |
1770 | * @catset: the Smack categories |
1771 | * @sap: where to put the netlabel categories |
1772 | * |
1773 | * Allocates and fills attr.mls.cat |
1774 | */ |
1775 | static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap) |
1776 | { |
1777 | unsigned char *cp; |
1778 | unsigned char m; |
1779 | int cat; |
1780 | int rc; |
1781 | int byte; |
1782 | |
1783 | if (!catset) |
1784 | return; |
1785 | |
1786 | sap->flags |= NETLBL_SECATTR_MLS_CAT; |
1787 | sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); |
1788 | sap->attr.mls.cat->startbit = 0; |
1789 | |
1790 | for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++) |
1791 | for (m = 0x80; m != 0; m >>= 1, cat++) { |
1792 | if ((m & *cp) == 0) |
1793 | continue; |
1794 | rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat, |
1795 | cat, GFP_ATOMIC); |
1796 | } |
1797 | } |
1798 | |
1799 | /** |
1800 | * smack_to_secattr - fill a secattr from a smack value |
1801 | * @smack: the smack value |
1802 | * @nlsp: where the result goes |
1803 | * |
1804 | * Casey says that CIPSO is good enough for now. |
1805 | * It can be used to effect. |
1806 | * It can also be abused to effect when necessary. |
1807 | * Apologies to the TSIG group in general and GW in particular. |
1808 | */ |
1809 | static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) |
1810 | { |
1811 | struct smack_cipso cipso; |
1812 | int rc; |
1813 | |
1814 | nlsp->domain = smack; |
1815 | nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; |
1816 | |
1817 | rc = smack_to_cipso(smack, &cipso); |
1818 | if (rc == 0) { |
1819 | nlsp->attr.mls.lvl = cipso.smk_level; |
1820 | smack_set_catset(cipso.smk_catset, nlsp); |
1821 | } else { |
1822 | nlsp->attr.mls.lvl = smack_cipso_direct; |
1823 | smack_set_catset(smack, nlsp); |
1824 | } |
1825 | } |
1826 | |
1827 | /** |
1828 | * smack_netlabel - Set the secattr on a socket |
1829 | * @sk: the socket |
1830 | * @labeled: socket label scheme |
1831 | * |
1832 | * Convert the outbound smack value (smk_out) to a |
1833 | * secattr and attach it to the socket. |
1834 | * |
1835 | * Returns 0 on success or an error code |
1836 | */ |
1837 | static int smack_netlabel(struct sock *sk, int labeled) |
1838 | { |
1839 | struct socket_smack *ssp = sk->sk_security; |
1840 | struct netlbl_lsm_secattr secattr; |
1841 | int rc = 0; |
1842 | |
1843 | /* |
1844 | * Usually the netlabel code will handle changing the |
1845 | * packet labeling based on the label. |
1846 | * The case of a single label host is different, because |
1847 | * a single label host should never get a labeled packet |
1848 | * even though the label is usually associated with a packet |
1849 | * label. |
1850 | */ |
1851 | local_bh_disable(); |
1852 | bh_lock_sock_nested(sk); |
1853 | |
1854 | if (ssp->smk_out == smack_net_ambient || |
1855 | labeled == SMACK_UNLABELED_SOCKET) |
1856 | netlbl_sock_delattr(sk); |
1857 | else { |
1858 | netlbl_secattr_init(&secattr); |
1859 | smack_to_secattr(ssp->smk_out, &secattr); |
1860 | rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr); |
1861 | netlbl_secattr_destroy(&secattr); |
1862 | } |
1863 | |
1864 | bh_unlock_sock(sk); |
1865 | local_bh_enable(); |
1866 | |
1867 | return rc; |
1868 | } |
1869 | |
1870 | /** |
1871 | * smack_netlbel_send - Set the secattr on a socket and perform access checks |
1872 | * @sk: the socket |
1873 | * @sap: the destination address |
1874 | * |
1875 | * Set the correct secattr for the given socket based on the destination |
1876 | * address and perform any outbound access checks needed. |
1877 | * |
1878 | * Returns 0 on success or an error code. |
1879 | * |
1880 | */ |
1881 | static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) |
1882 | { |
1883 | int rc; |
1884 | int sk_lbl; |
1885 | char *hostsp; |
1886 | struct socket_smack *ssp = sk->sk_security; |
1887 | struct smk_audit_info ad; |
1888 | |
1889 | rcu_read_lock(); |
1890 | hostsp = smack_host_label(sap); |
1891 | if (hostsp != NULL) { |
1892 | sk_lbl = SMACK_UNLABELED_SOCKET; |
1893 | #ifdef CONFIG_AUDIT |
1894 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); |
1895 | ad.a.u.net.family = sap->sin_family; |
1896 | ad.a.u.net.dport = sap->sin_port; |
1897 | ad.a.u.net.v4info.daddr = sap->sin_addr.s_addr; |
1898 | #endif |
1899 | rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad); |
1900 | } else { |
1901 | sk_lbl = SMACK_CIPSO_SOCKET; |
1902 | rc = 0; |
1903 | } |
1904 | rcu_read_unlock(); |
1905 | if (rc != 0) |
1906 | return rc; |
1907 | |
1908 | return smack_netlabel(sk, sk_lbl); |
1909 | } |
1910 | |
1911 | /** |
1912 | * smack_inode_setsecurity - set smack xattrs |
1913 | * @inode: the object |
1914 | * @name: attribute name |
1915 | * @value: attribute value |
1916 | * @size: size of the attribute |
1917 | * @flags: unused |
1918 | * |
1919 | * Sets the named attribute in the appropriate blob |
1920 | * |
1921 | * Returns 0 on success, or an error code |
1922 | */ |
1923 | static int smack_inode_setsecurity(struct inode *inode, const char *name, |
1924 | const void *value, size_t size, int flags) |
1925 | { |
1926 | char *sp; |
1927 | struct inode_smack *nsp = inode->i_security; |
1928 | struct socket_smack *ssp; |
1929 | struct socket *sock; |
1930 | int rc = 0; |
1931 | |
1932 | if (value == NULL || size > SMK_LABELLEN || size == 0) |
1933 | return -EACCES; |
1934 | |
1935 | sp = smk_import(value, size); |
1936 | if (sp == NULL) |
1937 | return -EINVAL; |
1938 | |
1939 | if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { |
1940 | nsp->smk_inode = sp; |
1941 | nsp->smk_flags |= SMK_INODE_INSTANT; |
1942 | return 0; |
1943 | } |
1944 | /* |
1945 | * The rest of the Smack xattrs are only on sockets. |
1946 | */ |
1947 | if (inode->i_sb->s_magic != SOCKFS_MAGIC) |
1948 | return -EOPNOTSUPP; |
1949 | |
1950 | sock = SOCKET_I(inode); |
1951 | if (sock == NULL || sock->sk == NULL) |
1952 | return -EOPNOTSUPP; |
1953 | |
1954 | ssp = sock->sk->sk_security; |
1955 | |
1956 | if (strcmp(name, XATTR_SMACK_IPIN) == 0) |
1957 | ssp->smk_in = sp; |
1958 | else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { |
1959 | ssp->smk_out = sp; |
1960 | if (sock->sk->sk_family != PF_UNIX) { |
1961 | rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
1962 | if (rc != 0) |
1963 | printk(KERN_WARNING |
1964 | "Smack: \"%s\" netlbl error %d.\n", |
1965 | __func__, -rc); |
1966 | } |
1967 | } else |
1968 | return -EOPNOTSUPP; |
1969 | |
1970 | return 0; |
1971 | } |
1972 | |
1973 | /** |
1974 | * smack_socket_post_create - finish socket setup |
1975 | * @sock: the socket |
1976 | * @family: protocol family |
1977 | * @type: unused |
1978 | * @protocol: unused |
1979 | * @kern: unused |
1980 | * |
1981 | * Sets the netlabel information on the socket |
1982 | * |
1983 | * Returns 0 on success, and error code otherwise |
1984 | */ |
1985 | static int smack_socket_post_create(struct socket *sock, int family, |
1986 | int type, int protocol, int kern) |
1987 | { |
1988 | if (family != PF_INET || sock->sk == NULL) |
1989 | return 0; |
1990 | /* |
1991 | * Set the outbound netlbl. |
1992 | */ |
1993 | return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
1994 | } |
1995 | |
1996 | /** |
1997 | * smack_socket_connect - connect access check |
1998 | * @sock: the socket |
1999 | * @sap: the other end |
2000 | * @addrlen: size of sap |
2001 | * |
2002 | * Verifies that a connection may be possible |
2003 | * |
2004 | * Returns 0 on success, and error code otherwise |
2005 | */ |
2006 | static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, |
2007 | int addrlen) |
2008 | { |
2009 | if (sock->sk == NULL || sock->sk->sk_family != PF_INET) |
2010 | return 0; |
2011 | if (addrlen < sizeof(struct sockaddr_in)) |
2012 | return -EINVAL; |
2013 | |
2014 | return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap); |
2015 | } |
2016 | |
2017 | /** |
2018 | * smack_flags_to_may - convert S_ to MAY_ values |
2019 | * @flags: the S_ value |
2020 | * |
2021 | * Returns the equivalent MAY_ value |
2022 | */ |
2023 | static int smack_flags_to_may(int flags) |
2024 | { |
2025 | int may = 0; |
2026 | |
2027 | if (flags & S_IRUGO) |
2028 | may |= MAY_READ; |
2029 | if (flags & S_IWUGO) |
2030 | may |= MAY_WRITE; |
2031 | if (flags & S_IXUGO) |
2032 | may |= MAY_EXEC; |
2033 | |
2034 | return may; |
2035 | } |
2036 | |
2037 | /** |
2038 | * smack_msg_msg_alloc_security - Set the security blob for msg_msg |
2039 | * @msg: the object |
2040 | * |
2041 | * Returns 0 |
2042 | */ |
2043 | static int smack_msg_msg_alloc_security(struct msg_msg *msg) |
2044 | { |
2045 | msg->security = smk_of_current(); |
2046 | return 0; |
2047 | } |
2048 | |
2049 | /** |
2050 | * smack_msg_msg_free_security - Clear the security blob for msg_msg |
2051 | * @msg: the object |
2052 | * |
2053 | * Clears the blob pointer |
2054 | */ |
2055 | static void smack_msg_msg_free_security(struct msg_msg *msg) |
2056 | { |
2057 | msg->security = NULL; |
2058 | } |
2059 | |
2060 | /** |
2061 | * smack_of_shm - the smack pointer for the shm |
2062 | * @shp: the object |
2063 | * |
2064 | * Returns a pointer to the smack value |
2065 | */ |
2066 | static char *smack_of_shm(struct shmid_kernel *shp) |
2067 | { |
2068 | return (char *)shp->shm_perm.security; |
2069 | } |
2070 | |
2071 | /** |
2072 | * smack_shm_alloc_security - Set the security blob for shm |
2073 | * @shp: the object |
2074 | * |
2075 | * Returns 0 |
2076 | */ |
2077 | static int smack_shm_alloc_security(struct shmid_kernel *shp) |
2078 | { |
2079 | struct kern_ipc_perm *isp = &shp->shm_perm; |
2080 | |
2081 | isp->security = smk_of_current(); |
2082 | return 0; |
2083 | } |
2084 | |
2085 | /** |
2086 | * smack_shm_free_security - Clear the security blob for shm |
2087 | * @shp: the object |
2088 | * |
2089 | * Clears the blob pointer |
2090 | */ |
2091 | static void smack_shm_free_security(struct shmid_kernel *shp) |
2092 | { |
2093 | struct kern_ipc_perm *isp = &shp->shm_perm; |
2094 | |
2095 | isp->security = NULL; |
2096 | } |
2097 | |
2098 | /** |
2099 | * smk_curacc_shm : check if current has access on shm |
2100 | * @shp : the object |
2101 | * @access : access requested |
2102 | * |
2103 | * Returns 0 if current has the requested access, error code otherwise |
2104 | */ |
2105 | static int smk_curacc_shm(struct shmid_kernel *shp, int access) |
2106 | { |
2107 | char *ssp = smack_of_shm(shp); |
2108 | struct smk_audit_info ad; |
2109 | |
2110 | #ifdef CONFIG_AUDIT |
2111 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); |
2112 | ad.a.u.ipc_id = shp->shm_perm.id; |
2113 | #endif |
2114 | return smk_curacc(ssp, access, &ad); |
2115 | } |
2116 | |
2117 | /** |
2118 | * smack_shm_associate - Smack access check for shm |
2119 | * @shp: the object |
2120 | * @shmflg: access requested |
2121 | * |
2122 | * Returns 0 if current has the requested access, error code otherwise |
2123 | */ |
2124 | static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) |
2125 | { |
2126 | int may; |
2127 | |
2128 | may = smack_flags_to_may(shmflg); |
2129 | return smk_curacc_shm(shp, may); |
2130 | } |
2131 | |
2132 | /** |
2133 | * smack_shm_shmctl - Smack access check for shm |
2134 | * @shp: the object |
2135 | * @cmd: what it wants to do |
2136 | * |
2137 | * Returns 0 if current has the requested access, error code otherwise |
2138 | */ |
2139 | static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) |
2140 | { |
2141 | int may; |
2142 | |
2143 | switch (cmd) { |
2144 | case IPC_STAT: |
2145 | case SHM_STAT: |
2146 | may = MAY_READ; |
2147 | break; |
2148 | case IPC_SET: |
2149 | case SHM_LOCK: |
2150 | case SHM_UNLOCK: |
2151 | case IPC_RMID: |
2152 | may = MAY_READWRITE; |
2153 | break; |
2154 | case IPC_INFO: |
2155 | case SHM_INFO: |
2156 | /* |
2157 | * System level information. |
2158 | */ |
2159 | return 0; |
2160 | default: |
2161 | return -EINVAL; |
2162 | } |
2163 | return smk_curacc_shm(shp, may); |
2164 | } |
2165 | |
2166 | /** |
2167 | * smack_shm_shmat - Smack access for shmat |
2168 | * @shp: the object |
2169 | * @shmaddr: unused |
2170 | * @shmflg: access requested |
2171 | * |
2172 | * Returns 0 if current has the requested access, error code otherwise |
2173 | */ |
2174 | static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, |
2175 | int shmflg) |
2176 | { |
2177 | int may; |
2178 | |
2179 | may = smack_flags_to_may(shmflg); |
2180 | return smk_curacc_shm(shp, may); |
2181 | } |
2182 | |
2183 | /** |
2184 | * smack_of_sem - the smack pointer for the sem |
2185 | * @sma: the object |
2186 | * |
2187 | * Returns a pointer to the smack value |
2188 | */ |
2189 | static char *smack_of_sem(struct sem_array *sma) |
2190 | { |
2191 | return (char *)sma->sem_perm.security; |
2192 | } |
2193 | |
2194 | /** |
2195 | * smack_sem_alloc_security - Set the security blob for sem |
2196 | * @sma: the object |
2197 | * |
2198 | * Returns 0 |
2199 | */ |
2200 | static int smack_sem_alloc_security(struct sem_array *sma) |
2201 | { |
2202 | struct kern_ipc_perm *isp = &sma->sem_perm; |
2203 | |
2204 | isp->security = smk_of_current(); |
2205 | return 0; |
2206 | } |
2207 | |
2208 | /** |
2209 | * smack_sem_free_security - Clear the security blob for sem |
2210 | * @sma: the object |
2211 | * |
2212 | * Clears the blob pointer |
2213 | */ |
2214 | static void smack_sem_free_security(struct sem_array *sma) |
2215 | { |
2216 | struct kern_ipc_perm *isp = &sma->sem_perm; |
2217 | |
2218 | isp->security = NULL; |
2219 | } |
2220 | |
2221 | /** |
2222 | * smk_curacc_sem : check if current has access on sem |
2223 | * @sma : the object |
2224 | * @access : access requested |
2225 | * |
2226 | * Returns 0 if current has the requested access, error code otherwise |
2227 | */ |
2228 | static int smk_curacc_sem(struct sem_array *sma, int access) |
2229 | { |
2230 | char *ssp = smack_of_sem(sma); |
2231 | struct smk_audit_info ad; |
2232 | |
2233 | #ifdef CONFIG_AUDIT |
2234 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); |
2235 | ad.a.u.ipc_id = sma->sem_perm.id; |
2236 | #endif |
2237 | return smk_curacc(ssp, access, &ad); |
2238 | } |
2239 | |
2240 | /** |
2241 | * smack_sem_associate - Smack access check for sem |
2242 | * @sma: the object |
2243 | * @semflg: access requested |
2244 | * |
2245 | * Returns 0 if current has the requested access, error code otherwise |
2246 | */ |
2247 | static int smack_sem_associate(struct sem_array *sma, int semflg) |
2248 | { |
2249 | int may; |
2250 | |
2251 | may = smack_flags_to_may(semflg); |
2252 | return smk_curacc_sem(sma, may); |
2253 | } |
2254 | |
2255 | /** |
2256 | * smack_sem_shmctl - Smack access check for sem |
2257 | * @sma: the object |
2258 | * @cmd: what it wants to do |
2259 | * |
2260 | * Returns 0 if current has the requested access, error code otherwise |
2261 | */ |
2262 | static int smack_sem_semctl(struct sem_array *sma, int cmd) |
2263 | { |
2264 | int may; |
2265 | |
2266 | switch (cmd) { |
2267 | case GETPID: |
2268 | case GETNCNT: |
2269 | case GETZCNT: |
2270 | case GETVAL: |
2271 | case GETALL: |
2272 | case IPC_STAT: |
2273 | case SEM_STAT: |
2274 | may = MAY_READ; |
2275 | break; |
2276 | case SETVAL: |
2277 | case SETALL: |
2278 | case IPC_RMID: |
2279 | case IPC_SET: |
2280 | may = MAY_READWRITE; |
2281 | break; |
2282 | case IPC_INFO: |
2283 | case SEM_INFO: |
2284 | /* |
2285 | * System level information |
2286 | */ |
2287 | return 0; |
2288 | default: |
2289 | return -EINVAL; |
2290 | } |
2291 | |
2292 | return smk_curacc_sem(sma, may); |
2293 | } |
2294 | |
2295 | /** |
2296 | * smack_sem_semop - Smack checks of semaphore operations |
2297 | * @sma: the object |
2298 | * @sops: unused |
2299 | * @nsops: unused |
2300 | * @alter: unused |
2301 | * |
2302 | * Treated as read and write in all cases. |
2303 | * |
2304 | * Returns 0 if access is allowed, error code otherwise |
2305 | */ |
2306 | static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, |
2307 | unsigned nsops, int alter) |
2308 | { |
2309 | return smk_curacc_sem(sma, MAY_READWRITE); |
2310 | } |
2311 | |
2312 | /** |
2313 | * smack_msg_alloc_security - Set the security blob for msg |
2314 | * @msq: the object |
2315 | * |
2316 | * Returns 0 |
2317 | */ |
2318 | static int smack_msg_queue_alloc_security(struct msg_queue *msq) |
2319 | { |
2320 | struct kern_ipc_perm *kisp = &msq->q_perm; |
2321 | |
2322 | kisp->security = smk_of_current(); |
2323 | return 0; |
2324 | } |
2325 | |
2326 | /** |
2327 | * smack_msg_free_security - Clear the security blob for msg |
2328 | * @msq: the object |
2329 | * |
2330 | * Clears the blob pointer |
2331 | */ |
2332 | static void smack_msg_queue_free_security(struct msg_queue *msq) |
2333 | { |
2334 | struct kern_ipc_perm *kisp = &msq->q_perm; |
2335 | |
2336 | kisp->security = NULL; |
2337 | } |
2338 | |
2339 | /** |
2340 | * smack_of_msq - the smack pointer for the msq |
2341 | * @msq: the object |
2342 | * |
2343 | * Returns a pointer to the smack value |
2344 | */ |
2345 | static char *smack_of_msq(struct msg_queue *msq) |
2346 | { |
2347 | return (char *)msq->q_perm.security; |
2348 | } |
2349 | |
2350 | /** |
2351 | * smk_curacc_msq : helper to check if current has access on msq |
2352 | * @msq : the msq |
2353 | * @access : access requested |
2354 | * |
2355 | * return 0 if current has access, error otherwise |
2356 | */ |
2357 | static int smk_curacc_msq(struct msg_queue *msq, int access) |
2358 | { |
2359 | char *msp = smack_of_msq(msq); |
2360 | struct smk_audit_info ad; |
2361 | |
2362 | #ifdef CONFIG_AUDIT |
2363 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); |
2364 | ad.a.u.ipc_id = msq->q_perm.id; |
2365 | #endif |
2366 | return smk_curacc(msp, access, &ad); |
2367 | } |
2368 | |
2369 | /** |
2370 | * smack_msg_queue_associate - Smack access check for msg_queue |
2371 | * @msq: the object |
2372 | * @msqflg: access requested |
2373 | * |
2374 | * Returns 0 if current has the requested access, error code otherwise |
2375 | */ |
2376 | static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) |
2377 | { |
2378 | int may; |
2379 | |
2380 | may = smack_flags_to_may(msqflg); |
2381 | return smk_curacc_msq(msq, may); |
2382 | } |
2383 | |
2384 | /** |
2385 | * smack_msg_queue_msgctl - Smack access check for msg_queue |
2386 | * @msq: the object |
2387 | * @cmd: what it wants to do |
2388 | * |
2389 | * Returns 0 if current has the requested access, error code otherwise |
2390 | */ |
2391 | static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) |
2392 | { |
2393 | int may; |
2394 | |
2395 | switch (cmd) { |
2396 | case IPC_STAT: |
2397 | case MSG_STAT: |
2398 | may = MAY_READ; |
2399 | break; |
2400 | case IPC_SET: |
2401 | case IPC_RMID: |
2402 | may = MAY_READWRITE; |
2403 | break; |
2404 | case IPC_INFO: |
2405 | case MSG_INFO: |
2406 | /* |
2407 | * System level information |
2408 | */ |
2409 | return 0; |
2410 | default: |
2411 | return -EINVAL; |
2412 | } |
2413 | |
2414 | return smk_curacc_msq(msq, may); |
2415 | } |
2416 | |
2417 | /** |
2418 | * smack_msg_queue_msgsnd - Smack access check for msg_queue |
2419 | * @msq: the object |
2420 | * @msg: unused |
2421 | * @msqflg: access requested |
2422 | * |
2423 | * Returns 0 if current has the requested access, error code otherwise |
2424 | */ |
2425 | static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, |
2426 | int msqflg) |
2427 | { |
2428 | int may; |
2429 | |
2430 | may = smack_flags_to_may(msqflg); |
2431 | return smk_curacc_msq(msq, may); |
2432 | } |
2433 | |
2434 | /** |
2435 | * smack_msg_queue_msgsnd - Smack access check for msg_queue |
2436 | * @msq: the object |
2437 | * @msg: unused |
2438 | * @target: unused |
2439 | * @type: unused |
2440 | * @mode: unused |
2441 | * |
2442 | * Returns 0 if current has read and write access, error code otherwise |
2443 | */ |
2444 | static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, |
2445 | struct task_struct *target, long type, int mode) |
2446 | { |
2447 | return smk_curacc_msq(msq, MAY_READWRITE); |
2448 | } |
2449 | |
2450 | /** |
2451 | * smack_ipc_permission - Smack access for ipc_permission() |
2452 | * @ipp: the object permissions |
2453 | * @flag: access requested |
2454 | * |
2455 | * Returns 0 if current has read and write access, error code otherwise |
2456 | */ |
2457 | static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) |
2458 | { |
2459 | char *isp = ipp->security; |
2460 | int may = smack_flags_to_may(flag); |
2461 | struct smk_audit_info ad; |
2462 | |
2463 | #ifdef CONFIG_AUDIT |
2464 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); |
2465 | ad.a.u.ipc_id = ipp->id; |
2466 | #endif |
2467 | return smk_curacc(isp, may, &ad); |
2468 | } |
2469 | |
2470 | /** |
2471 | * smack_ipc_getsecid - Extract smack security id |
2472 | * @ipp: the object permissions |
2473 | * @secid: where result will be saved |
2474 | */ |
2475 | static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) |
2476 | { |
2477 | char *smack = ipp->security; |
2478 | |
2479 | *secid = smack_to_secid(smack); |
2480 | } |
2481 | |
2482 | /** |
2483 | * smack_d_instantiate - Make sure the blob is correct on an inode |
2484 | * @opt_dentry: dentry where inode will be attached |
2485 | * @inode: the object |
2486 | * |
2487 | * Set the inode's security blob if it hasn't been done already. |
2488 | */ |
2489 | static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) |
2490 | { |
2491 | struct super_block *sbp; |
2492 | struct superblock_smack *sbsp; |
2493 | struct inode_smack *isp; |
2494 | char *csp = smk_of_current(); |
2495 | char *fetched; |
2496 | char *final; |
2497 | char trattr[TRANS_TRUE_SIZE]; |
2498 | int transflag = 0; |
2499 | struct dentry *dp; |
2500 | |
2501 | if (inode == NULL) |
2502 | return; |
2503 | |
2504 | isp = inode->i_security; |
2505 | |
2506 | mutex_lock(&isp->smk_lock); |
2507 | /* |
2508 | * If the inode is already instantiated |
2509 | * take the quick way out |
2510 | */ |
2511 | if (isp->smk_flags & SMK_INODE_INSTANT) |
2512 | goto unlockandout; |
2513 | |
2514 | sbp = inode->i_sb; |
2515 | sbsp = sbp->s_security; |
2516 | /* |
2517 | * We're going to use the superblock default label |
2518 | * if there's no label on the file. |
2519 | */ |
2520 | final = sbsp->smk_default; |
2521 | |
2522 | /* |
2523 | * If this is the root inode the superblock |
2524 | * may be in the process of initialization. |
2525 | * If that is the case use the root value out |
2526 | * of the superblock. |
2527 | */ |
2528 | if (opt_dentry->d_parent == opt_dentry) { |
2529 | isp->smk_inode = sbsp->smk_root; |
2530 | isp->smk_flags |= SMK_INODE_INSTANT; |
2531 | goto unlockandout; |
2532 | } |
2533 | |
2534 | /* |
2535 | * This is pretty hackish. |
2536 | * Casey says that we shouldn't have to do |
2537 | * file system specific code, but it does help |
2538 | * with keeping it simple. |
2539 | */ |
2540 | switch (sbp->s_magic) { |
2541 | case SMACK_MAGIC: |
2542 | /* |
2543 | * Casey says that it's a little embarrassing |
2544 | * that the smack file system doesn't do |
2545 | * extended attributes. |
2546 | */ |
2547 | final = smack_known_star.smk_known; |
2548 | break; |
2549 | case PIPEFS_MAGIC: |
2550 | /* |
2551 | * Casey says pipes are easy (?) |
2552 | */ |
2553 | final = smack_known_star.smk_known; |
2554 | break; |
2555 | case DEVPTS_SUPER_MAGIC: |
2556 | /* |
2557 | * devpts seems content with the label of the task. |
2558 | * Programs that change smack have to treat the |
2559 | * pty with respect. |
2560 | */ |
2561 | final = csp; |
2562 | break; |
2563 | case SOCKFS_MAGIC: |
2564 | /* |
2565 | * Socket access is controlled by the socket |
2566 | * structures associated with the task involved. |
2567 | */ |
2568 | final = smack_known_star.smk_known; |
2569 | break; |
2570 | case PROC_SUPER_MAGIC: |
2571 | /* |
2572 | * Casey says procfs appears not to care. |
2573 | * The superblock default suffices. |
2574 | */ |
2575 | break; |
2576 | case TMPFS_MAGIC: |
2577 | /* |
2578 | * Device labels should come from the filesystem, |
2579 | * but watch out, because they're volitile, |
2580 | * getting recreated on every reboot. |
2581 | */ |
2582 | final = smack_known_star.smk_known; |
2583 | /* |
2584 | * No break. |
2585 | * |
2586 | * If a smack value has been set we want to use it, |
2587 | * but since tmpfs isn't giving us the opportunity |
2588 | * to set mount options simulate setting the |
2589 | * superblock default. |
2590 | */ |
2591 | default: |
2592 | /* |
2593 | * This isn't an understood special case. |
2594 | * Get the value from the xattr. |
2595 | */ |
2596 | |
2597 | /* |
2598 | * UNIX domain sockets use lower level socket data. |
2599 | */ |
2600 | if (S_ISSOCK(inode->i_mode)) { |
2601 | final = smack_known_star.smk_known; |
2602 | break; |
2603 | } |
2604 | /* |
2605 | * No xattr support means, alas, no SMACK label. |
2606 | * Use the aforeapplied default. |
2607 | * It would be curious if the label of the task |
2608 | * does not match that assigned. |
2609 | */ |
2610 | if (inode->i_op->getxattr == NULL) |
2611 | break; |
2612 | /* |
2613 | * Get the dentry for xattr. |
2614 | */ |
2615 | dp = dget(opt_dentry); |
2616 | fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp); |
2617 | if (fetched != NULL) { |
2618 | final = fetched; |
2619 | if (S_ISDIR(inode->i_mode)) { |
2620 | trattr[0] = '\0'; |
2621 | inode->i_op->getxattr(dp, |
2622 | XATTR_NAME_SMACKTRANSMUTE, |
2623 | trattr, TRANS_TRUE_SIZE); |
2624 | if (strncmp(trattr, TRANS_TRUE, |
2625 | TRANS_TRUE_SIZE) == 0) |
2626 | transflag = SMK_INODE_TRANSMUTE; |
2627 | } |
2628 | } |
2629 | isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); |
2630 | isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); |
2631 | |
2632 | dput(dp); |
2633 | break; |
2634 | } |
2635 | |
2636 | if (final == NULL) |
2637 | isp->smk_inode = csp; |
2638 | else |
2639 | isp->smk_inode = final; |
2640 | |
2641 | isp->smk_flags |= (SMK_INODE_INSTANT | transflag); |
2642 | |
2643 | unlockandout: |
2644 | mutex_unlock(&isp->smk_lock); |
2645 | return; |
2646 | } |
2647 | |
2648 | /** |
2649 | * smack_getprocattr - Smack process attribute access |
2650 | * @p: the object task |
2651 | * @name: the name of the attribute in /proc/.../attr |
2652 | * @value: where to put the result |
2653 | * |
2654 | * Places a copy of the task Smack into value |
2655 | * |
2656 | * Returns the length of the smack label or an error code |
2657 | */ |
2658 | static int smack_getprocattr(struct task_struct *p, char *name, char **value) |
2659 | { |
2660 | char *cp; |
2661 | int slen; |
2662 | |
2663 | if (strcmp(name, "current") != 0) |
2664 | return -EINVAL; |
2665 | |
2666 | cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL); |
2667 | if (cp == NULL) |
2668 | return -ENOMEM; |
2669 | |
2670 | slen = strlen(cp); |
2671 | *value = cp; |
2672 | return slen; |
2673 | } |
2674 | |
2675 | /** |
2676 | * smack_setprocattr - Smack process attribute setting |
2677 | * @p: the object task |
2678 | * @name: the name of the attribute in /proc/.../attr |
2679 | * @value: the value to set |
2680 | * @size: the size of the value |
2681 | * |
2682 | * Sets the Smack value of the task. Only setting self |
2683 | * is permitted and only with privilege |
2684 | * |
2685 | * Returns the length of the smack label or an error code |
2686 | */ |
2687 | static int smack_setprocattr(struct task_struct *p, char *name, |
2688 | void *value, size_t size) |
2689 | { |
2690 | int rc; |
2691 | struct task_smack *tsp; |
2692 | struct task_smack *oldtsp; |
2693 | struct cred *new; |
2694 | char *newsmack; |
2695 | |
2696 | /* |
2697 | * Changing another process' Smack value is too dangerous |
2698 | * and supports no sane use case. |
2699 | */ |
2700 | if (p != current) |
2701 | return -EPERM; |
2702 | |
2703 | if (!capable(CAP_MAC_ADMIN)) |
2704 | return -EPERM; |
2705 | |
2706 | if (value == NULL || size == 0 || size >= SMK_LABELLEN) |
2707 | return -EINVAL; |
2708 | |
2709 | if (strcmp(name, "current") != 0) |
2710 | return -EINVAL; |
2711 | |
2712 | newsmack = smk_import(value, size); |
2713 | if (newsmack == NULL) |
2714 | return -EINVAL; |
2715 | |
2716 | /* |
2717 | * No process is ever allowed the web ("@") label. |
2718 | */ |
2719 | if (newsmack == smack_known_web.smk_known) |
2720 | return -EPERM; |
2721 | |
2722 | oldtsp = p->cred->security; |
2723 | new = prepare_creds(); |
2724 | if (new == NULL) |
2725 | return -ENOMEM; |
2726 | |
2727 | tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL); |
2728 | if (tsp == NULL) { |
2729 | kfree(new); |
2730 | return -ENOMEM; |
2731 | } |
2732 | rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL); |
2733 | if (rc != 0) |
2734 | return rc; |
2735 | |
2736 | new->security = tsp; |
2737 | commit_creds(new); |
2738 | return size; |
2739 | } |
2740 | |
2741 | /** |
2742 | * smack_unix_stream_connect - Smack access on UDS |
2743 | * @sock: one sock |
2744 | * @other: the other sock |
2745 | * @newsk: unused |
2746 | * |
2747 | * Return 0 if a subject with the smack of sock could access |
2748 | * an object with the smack of other, otherwise an error code |
2749 | */ |
2750 | static int smack_unix_stream_connect(struct sock *sock, |
2751 | struct sock *other, struct sock *newsk) |
2752 | { |
2753 | struct socket_smack *ssp = sock->sk_security; |
2754 | struct socket_smack *osp = other->sk_security; |
2755 | struct smk_audit_info ad; |
2756 | int rc = 0; |
2757 | |
2758 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); |
2759 | smk_ad_setfield_u_net_sk(&ad, other); |
2760 | |
2761 | if (!capable(CAP_MAC_OVERRIDE)) |
2762 | rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad); |
2763 | |
2764 | return rc; |
2765 | } |
2766 | |
2767 | /** |
2768 | * smack_unix_may_send - Smack access on UDS |
2769 | * @sock: one socket |
2770 | * @other: the other socket |
2771 | * |
2772 | * Return 0 if a subject with the smack of sock could access |
2773 | * an object with the smack of other, otherwise an error code |
2774 | */ |
2775 | static int smack_unix_may_send(struct socket *sock, struct socket *other) |
2776 | { |
2777 | struct socket_smack *ssp = sock->sk->sk_security; |
2778 | struct socket_smack *osp = other->sk->sk_security; |
2779 | struct smk_audit_info ad; |
2780 | int rc = 0; |
2781 | |
2782 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); |
2783 | smk_ad_setfield_u_net_sk(&ad, other->sk); |
2784 | |
2785 | if (!capable(CAP_MAC_OVERRIDE)) |
2786 | rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad); |
2787 | |
2788 | return rc; |
2789 | } |
2790 | |
2791 | /** |
2792 | * smack_socket_sendmsg - Smack check based on destination host |
2793 | * @sock: the socket |
2794 | * @msg: the message |
2795 | * @size: the size of the message |
2796 | * |
2797 | * Return 0 if the current subject can write to the destination |
2798 | * host. This is only a question if the destination is a single |
2799 | * label host. |
2800 | */ |
2801 | static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
2802 | int size) |
2803 | { |
2804 | struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; |
2805 | |
2806 | /* |
2807 | * Perfectly reasonable for this to be NULL |
2808 | */ |
2809 | if (sip == NULL || sip->sin_family != AF_INET) |
2810 | return 0; |
2811 | |
2812 | return smack_netlabel_send(sock->sk, sip); |
2813 | } |
2814 | |
2815 | |
2816 | /** |
2817 | * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack |
2818 | * @sap: netlabel secattr |
2819 | * @sip: where to put the result |
2820 | * |
2821 | * Copies a smack label into sip |
2822 | */ |
2823 | static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip) |
2824 | { |
2825 | char smack[SMK_LABELLEN]; |
2826 | char *sp; |
2827 | int pcat; |
2828 | |
2829 | if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { |
2830 | /* |
2831 | * Looks like a CIPSO packet. |
2832 | * If there are flags but no level netlabel isn't |
2833 | * behaving the way we expect it to. |
2834 | * |
2835 | * Get the categories, if any |
2836 | * Without guidance regarding the smack value |
2837 | * for the packet fall back on the network |
2838 | * ambient value. |
2839 | */ |
2840 | memset(smack, '\0', SMK_LABELLEN); |
2841 | if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0) |
2842 | for (pcat = -1;;) { |
2843 | pcat = netlbl_secattr_catmap_walk( |
2844 | sap->attr.mls.cat, pcat + 1); |
2845 | if (pcat < 0) |
2846 | break; |
2847 | smack_catset_bit(pcat, smack); |
2848 | } |
2849 | /* |
2850 | * If it is CIPSO using smack direct mapping |
2851 | * we are already done. WeeHee. |
2852 | */ |
2853 | if (sap->attr.mls.lvl == smack_cipso_direct) { |
2854 | memcpy(sip, smack, SMK_MAXLEN); |
2855 | return; |
2856 | } |
2857 | /* |
2858 | * Look it up in the supplied table if it is not |
2859 | * a direct mapping. |
2860 | */ |
2861 | smack_from_cipso(sap->attr.mls.lvl, smack, sip); |
2862 | return; |
2863 | } |
2864 | if ((sap->flags & NETLBL_SECATTR_SECID) != 0) { |
2865 | /* |
2866 | * Looks like a fallback, which gives us a secid. |
2867 | */ |
2868 | sp = smack_from_secid(sap->attr.secid); |
2869 | /* |
2870 | * This has got to be a bug because it is |
2871 | * impossible to specify a fallback without |
2872 | * specifying the label, which will ensure |
2873 | * it has a secid, and the only way to get a |
2874 | * secid is from a fallback. |
2875 | */ |
2876 | BUG_ON(sp == NULL); |
2877 | strncpy(sip, sp, SMK_MAXLEN); |
2878 | return; |
2879 | } |
2880 | /* |
2881 | * Without guidance regarding the smack value |
2882 | * for the packet fall back on the network |
2883 | * ambient value. |
2884 | */ |
2885 | strncpy(sip, smack_net_ambient, SMK_MAXLEN); |
2886 | return; |
2887 | } |
2888 | |
2889 | /** |
2890 | * smack_socket_sock_rcv_skb - Smack packet delivery access check |
2891 | * @sk: socket |
2892 | * @skb: packet |
2893 | * |
2894 | * Returns 0 if the packet should be delivered, an error code otherwise |
2895 | */ |
2896 | static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
2897 | { |
2898 | struct netlbl_lsm_secattr secattr; |
2899 | struct socket_smack *ssp = sk->sk_security; |
2900 | char smack[SMK_LABELLEN]; |
2901 | char *csp; |
2902 | int rc; |
2903 | struct smk_audit_info ad; |
2904 | if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) |
2905 | return 0; |
2906 | |
2907 | /* |
2908 | * Translate what netlabel gave us. |
2909 | */ |
2910 | netlbl_secattr_init(&secattr); |
2911 | |
2912 | rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); |
2913 | if (rc == 0) { |
2914 | smack_from_secattr(&secattr, smack); |
2915 | csp = smack; |
2916 | } else |
2917 | csp = smack_net_ambient; |
2918 | |
2919 | netlbl_secattr_destroy(&secattr); |
2920 | |
2921 | #ifdef CONFIG_AUDIT |
2922 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); |
2923 | ad.a.u.net.family = sk->sk_family; |
2924 | ad.a.u.net.netif = skb->skb_iif; |
2925 | ipv4_skb_to_auditdata(skb, &ad.a, NULL); |
2926 | #endif |
2927 | /* |
2928 | * Receiving a packet requires that the other end |
2929 | * be able to write here. Read access is not required. |
2930 | * This is the simplist possible security model |
2931 | * for networking. |
2932 | */ |
2933 | rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad); |
2934 | if (rc != 0) |
2935 | netlbl_skbuff_err(skb, rc, 0); |
2936 | return rc; |
2937 | } |
2938 | |
2939 | /** |
2940 | * smack_socket_getpeersec_stream - pull in packet label |
2941 | * @sock: the socket |
2942 | * @optval: user's destination |
2943 | * @optlen: size thereof |
2944 | * @len: max thereof |
2945 | * |
2946 | * returns zero on success, an error code otherwise |
2947 | */ |
2948 | static int smack_socket_getpeersec_stream(struct socket *sock, |
2949 | char __user *optval, |
2950 | int __user *optlen, unsigned len) |
2951 | { |
2952 | struct socket_smack *ssp; |
2953 | int slen; |
2954 | int rc = 0; |
2955 | |
2956 | ssp = sock->sk->sk_security; |
2957 | slen = strlen(ssp->smk_packet) + 1; |
2958 | |
2959 | if (slen > len) |
2960 | rc = -ERANGE; |
2961 | else if (copy_to_user(optval, ssp->smk_packet, slen) != 0) |
2962 | rc = -EFAULT; |
2963 | |
2964 | if (put_user(slen, optlen) != 0) |
2965 | rc = -EFAULT; |
2966 | |
2967 | return rc; |
2968 | } |
2969 | |
2970 | |
2971 | /** |
2972 | * smack_socket_getpeersec_dgram - pull in packet label |
2973 | * @sock: the peer socket |
2974 | * @skb: packet data |
2975 | * @secid: pointer to where to put the secid of the packet |
2976 | * |
2977 | * Sets the netlabel socket state on sk from parent |
2978 | */ |
2979 | static int smack_socket_getpeersec_dgram(struct socket *sock, |
2980 | struct sk_buff *skb, u32 *secid) |
2981 | |
2982 | { |
2983 | struct netlbl_lsm_secattr secattr; |
2984 | struct socket_smack *sp; |
2985 | char smack[SMK_LABELLEN]; |
2986 | int family = PF_UNSPEC; |
2987 | u32 s = 0; /* 0 is the invalid secid */ |
2988 | int rc; |
2989 | |
2990 | if (skb != NULL) { |
2991 | if (skb->protocol == htons(ETH_P_IP)) |
2992 | family = PF_INET; |
2993 | else if (skb->protocol == htons(ETH_P_IPV6)) |
2994 | family = PF_INET6; |
2995 | } |
2996 | if (family == PF_UNSPEC && sock != NULL) |
2997 | family = sock->sk->sk_family; |
2998 | |
2999 | if (family == PF_UNIX) { |
3000 | sp = sock->sk->sk_security; |
3001 | s = smack_to_secid(sp->smk_out); |
3002 | } else if (family == PF_INET || family == PF_INET6) { |
3003 | /* |
3004 | * Translate what netlabel gave us. |
3005 | */ |
3006 | netlbl_secattr_init(&secattr); |
3007 | rc = netlbl_skbuff_getattr(skb, family, &secattr); |
3008 | if (rc == 0) { |
3009 | smack_from_secattr(&secattr, smack); |
3010 | s = smack_to_secid(smack); |
3011 | } |
3012 | netlbl_secattr_destroy(&secattr); |
3013 | } |
3014 | *secid = s; |
3015 | if (s == 0) |
3016 | return -EINVAL; |
3017 | return 0; |
3018 | } |
3019 | |
3020 | /** |
3021 | * smack_sock_graft - Initialize a newly created socket with an existing sock |
3022 | * @sk: child sock |
3023 | * @parent: parent socket |
3024 | * |
3025 | * Set the smk_{in,out} state of an existing sock based on the process that |
3026 | * is creating the new socket. |
3027 | */ |
3028 | static void smack_sock_graft(struct sock *sk, struct socket *parent) |
3029 | { |
3030 | struct socket_smack *ssp; |
3031 | |
3032 | if (sk == NULL || |
3033 | (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)) |
3034 | return; |
3035 | |
3036 | ssp = sk->sk_security; |
3037 | ssp->smk_in = ssp->smk_out = smk_of_current(); |
3038 | /* cssp->smk_packet is already set in smack_inet_csk_clone() */ |
3039 | } |
3040 | |
3041 | /** |
3042 | * smack_inet_conn_request - Smack access check on connect |
3043 | * @sk: socket involved |
3044 | * @skb: packet |
3045 | * @req: unused |
3046 | * |
3047 | * Returns 0 if a task with the packet label could write to |
3048 | * the socket, otherwise an error code |
3049 | */ |
3050 | static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, |
3051 | struct request_sock *req) |
3052 | { |
3053 | u16 family = sk->sk_family; |
3054 | struct socket_smack *ssp = sk->sk_security; |
3055 | struct netlbl_lsm_secattr secattr; |
3056 | struct sockaddr_in addr; |
3057 | struct iphdr *hdr; |
3058 | char smack[SMK_LABELLEN]; |
3059 | int rc; |
3060 | struct smk_audit_info ad; |
3061 | |
3062 | /* handle mapped IPv4 packets arriving via IPv6 sockets */ |
3063 | if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) |
3064 | family = PF_INET; |
3065 | |
3066 | netlbl_secattr_init(&secattr); |
3067 | rc = netlbl_skbuff_getattr(skb, family, &secattr); |
3068 | if (rc == 0) |
3069 | smack_from_secattr(&secattr, smack); |
3070 | else |
3071 | strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); |
3072 | netlbl_secattr_destroy(&secattr); |
3073 | |
3074 | #ifdef CONFIG_AUDIT |
3075 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NET); |
3076 | ad.a.u.net.family = family; |
3077 | ad.a.u.net.netif = skb->skb_iif; |
3078 | ipv4_skb_to_auditdata(skb, &ad.a, NULL); |
3079 | #endif |
3080 | /* |
3081 | * Receiving a packet requires that the other end be able to write |
3082 | * here. Read access is not required. |
3083 | */ |
3084 | rc = smk_access(smack, ssp->smk_in, MAY_WRITE, &ad); |
3085 | if (rc != 0) |
3086 | return rc; |
3087 | |
3088 | /* |
3089 | * Save the peer's label in the request_sock so we can later setup |
3090 | * smk_packet in the child socket so that SO_PEERCRED can report it. |
3091 | */ |
3092 | req->peer_secid = smack_to_secid(smack); |
3093 | |
3094 | /* |
3095 | * We need to decide if we want to label the incoming connection here |
3096 | * if we do we only need to label the request_sock and the stack will |
3097 | * propagate the wire-label to the sock when it is created. |
3098 | */ |
3099 | hdr = ip_hdr(skb); |
3100 | addr.sin_addr.s_addr = hdr->saddr; |
3101 | rcu_read_lock(); |
3102 | if (smack_host_label(&addr) == NULL) { |
3103 | rcu_read_unlock(); |
3104 | netlbl_secattr_init(&secattr); |
3105 | smack_to_secattr(smack, &secattr); |
3106 | rc = netlbl_req_setattr(req, &secattr); |
3107 | netlbl_secattr_destroy(&secattr); |
3108 | } else { |
3109 | rcu_read_unlock(); |
3110 | netlbl_req_delattr(req); |
3111 | } |
3112 | |
3113 | return rc; |
3114 | } |
3115 | |
3116 | /** |
3117 | * smack_inet_csk_clone - Copy the connection information to the new socket |
3118 | * @sk: the new socket |
3119 | * @req: the connection's request_sock |
3120 | * |
3121 | * Transfer the connection's peer label to the newly created socket. |
3122 | */ |
3123 | static void smack_inet_csk_clone(struct sock *sk, |
3124 | const struct request_sock *req) |
3125 | { |
3126 | struct socket_smack *ssp = sk->sk_security; |
3127 | char *smack; |
3128 | |
3129 | if (req->peer_secid != 0) { |
3130 | smack = smack_from_secid(req->peer_secid); |
3131 | strncpy(ssp->smk_packet, smack, SMK_MAXLEN); |
3132 | } else |
3133 | ssp->smk_packet[0] = '\0'; |
3134 | } |
3135 | |
3136 | /* |
3137 | * Key management security hooks |
3138 | * |
3139 | * Casey has not tested key support very heavily. |
3140 | * The permission check is most likely too restrictive. |
3141 | * If you care about keys please have a look. |
3142 | */ |
3143 | #ifdef CONFIG_KEYS |
3144 | |
3145 | /** |
3146 | * smack_key_alloc - Set the key security blob |
3147 | * @key: object |
3148 | * @cred: the credentials to use |
3149 | * @flags: unused |
3150 | * |
3151 | * No allocation required |
3152 | * |
3153 | * Returns 0 |
3154 | */ |
3155 | static int smack_key_alloc(struct key *key, const struct cred *cred, |
3156 | unsigned long flags) |
3157 | { |
3158 | key->security = smk_of_task(cred->security); |
3159 | return 0; |
3160 | } |
3161 | |
3162 | /** |
3163 | * smack_key_free - Clear the key security blob |
3164 | * @key: the object |
3165 | * |
3166 | * Clear the blob pointer |
3167 | */ |
3168 | static void smack_key_free(struct key *key) |
3169 | { |
3170 | key->security = NULL; |
3171 | } |
3172 | |
3173 | /* |
3174 | * smack_key_permission - Smack access on a key |
3175 | * @key_ref: gets to the object |
3176 | * @cred: the credentials to use |
3177 | * @perm: unused |
3178 | * |
3179 | * Return 0 if the task has read and write to the object, |
3180 | * an error code otherwise |
3181 | */ |
3182 | static int smack_key_permission(key_ref_t key_ref, |
3183 | const struct cred *cred, key_perm_t perm) |
3184 | { |
3185 | struct key *keyp; |
3186 | struct smk_audit_info ad; |
3187 | char *tsp = smk_of_task(cred->security); |
3188 | |
3189 | keyp = key_ref_to_ptr(key_ref); |
3190 | if (keyp == NULL) |
3191 | return -EINVAL; |
3192 | /* |
3193 | * If the key hasn't been initialized give it access so that |
3194 | * it may do so. |
3195 | */ |
3196 | if (keyp->security == NULL) |
3197 | return 0; |
3198 | /* |
3199 | * This should not occur |
3200 | */ |
3201 | if (tsp == NULL) |
3202 | return -EACCES; |
3203 | #ifdef CONFIG_AUDIT |
3204 | smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); |
3205 | ad.a.u.key_struct.key = keyp->serial; |
3206 | ad.a.u.key_struct.key_desc = keyp->description; |
3207 | #endif |
3208 | return smk_access(tsp, keyp->security, |
3209 | MAY_READWRITE, &ad); |
3210 | } |
3211 | #endif /* CONFIG_KEYS */ |
3212 | |
3213 | /* |
3214 | * Smack Audit hooks |
3215 | * |
3216 | * Audit requires a unique representation of each Smack specific |
3217 | * rule. This unique representation is used to distinguish the |
3218 | * object to be audited from remaining kernel objects and also |
3219 | * works as a glue between the audit hooks. |
3220 | * |
3221 | * Since repository entries are added but never deleted, we'll use |
3222 | * the smack_known label address related to the given audit rule as |
3223 | * the needed unique representation. This also better fits the smack |
3224 | * model where nearly everything is a label. |
3225 | */ |
3226 | #ifdef CONFIG_AUDIT |
3227 | |
3228 | /** |
3229 | * smack_audit_rule_init - Initialize a smack audit rule |
3230 | * @field: audit rule fields given from user-space (audit.h) |
3231 | * @op: required testing operator (=, !=, >, <, ...) |
3232 | * @rulestr: smack label to be audited |
3233 | * @vrule: pointer to save our own audit rule representation |
3234 | * |
3235 | * Prepare to audit cases where (@field @op @rulestr) is true. |
3236 | * The label to be audited is created if necessay. |
3237 | */ |
3238 | static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) |
3239 | { |
3240 | char **rule = (char **)vrule; |
3241 | *rule = NULL; |
3242 | |
3243 | if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) |
3244 | return -EINVAL; |
3245 | |
3246 | if (op != Audit_equal && op != Audit_not_equal) |
3247 | return -EINVAL; |
3248 | |
3249 | *rule = smk_import(rulestr, 0); |
3250 | |
3251 | return 0; |
3252 | } |
3253 | |
3254 | /** |
3255 | * smack_audit_rule_known - Distinguish Smack audit rules |
3256 | * @krule: rule of interest, in Audit kernel representation format |
3257 | * |
3258 | * This is used to filter Smack rules from remaining Audit ones. |
3259 | * If it's proved that this rule belongs to us, the |
3260 | * audit_rule_match hook will be called to do the final judgement. |
3261 | */ |
3262 | static int smack_audit_rule_known(struct audit_krule *krule) |
3263 | { |
3264 | struct audit_field *f; |
3265 | int i; |
3266 | |
3267 | for (i = 0; i < krule->field_count; i++) { |
3268 | f = &krule->fields[i]; |
3269 | |
3270 | if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER) |
3271 | return 1; |
3272 | } |
3273 | |
3274 | return 0; |
3275 | } |
3276 | |
3277 | /** |
3278 | * smack_audit_rule_match - Audit given object ? |
3279 | * @secid: security id for identifying the object to test |
3280 | * @field: audit rule flags given from user-space |
3281 | * @op: required testing operator |
3282 | * @vrule: smack internal rule presentation |
3283 | * @actx: audit context associated with the check |
3284 | * |
3285 | * The core Audit hook. It's used to take the decision of |
3286 | * whether to audit or not to audit a given object. |
3287 | */ |
3288 | static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule, |
3289 | struct audit_context *actx) |
3290 | { |
3291 | char *smack; |
3292 | char *rule = vrule; |
3293 | |
3294 | if (!rule) { |
3295 | audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR, |
3296 | "Smack: missing rule\n"); |
3297 | return -ENOENT; |
3298 | } |
3299 | |
3300 | if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) |
3301 | return 0; |
3302 | |
3303 | smack = smack_from_secid(secid); |
3304 | |
3305 | /* |
3306 | * No need to do string comparisons. If a match occurs, |
3307 | * both pointers will point to the same smack_known |
3308 | * label. |
3309 | */ |
3310 | if (op == Audit_equal) |
3311 | return (rule == smack); |
3312 | if (op == Audit_not_equal) |
3313 | return (rule != smack); |
3314 | |
3315 | return 0; |
3316 | } |
3317 | |
3318 | /** |
3319 | * smack_audit_rule_free - free smack rule representation |
3320 | * @vrule: rule to be freed. |
3321 | * |
3322 | * No memory was allocated. |
3323 | */ |
3324 | static void smack_audit_rule_free(void *vrule) |
3325 | { |
3326 | /* No-op */ |
3327 | } |
3328 | |
3329 | #endif /* CONFIG_AUDIT */ |
3330 | |
3331 | /** |
3332 | * smack_secid_to_secctx - return the smack label for a secid |
3333 | * @secid: incoming integer |
3334 | * @secdata: destination |
3335 | * @seclen: how long it is |
3336 | * |
3337 | * Exists for networking code. |
3338 | */ |
3339 | static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) |
3340 | { |
3341 | char *sp = smack_from_secid(secid); |
3342 | |
3343 | if (secdata) |
3344 | *secdata = sp; |
3345 | *seclen = strlen(sp); |
3346 | return 0; |
3347 | } |
3348 | |
3349 | /** |
3350 | * smack_secctx_to_secid - return the secid for a smack label |
3351 | * @secdata: smack label |
3352 | * @seclen: how long result is |
3353 | * @secid: outgoing integer |
3354 | * |
3355 | * Exists for audit and networking code. |
3356 | */ |
3357 | static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
3358 | { |
3359 | *secid = smack_to_secid(secdata); |
3360 | return 0; |
3361 | } |
3362 | |
3363 | /** |
3364 | * smack_release_secctx - don't do anything. |
3365 | * @secdata: unused |
3366 | * @seclen: unused |
3367 | * |
3368 | * Exists to make sure nothing gets done, and properly |
3369 | */ |
3370 | static void smack_release_secctx(char *secdata, u32 seclen) |
3371 | { |
3372 | } |
3373 | |
3374 | static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) |
3375 | { |
3376 | return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0); |
3377 | } |
3378 | |
3379 | static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) |
3380 | { |
3381 | return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0); |
3382 | } |
3383 | |
3384 | static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) |
3385 | { |
3386 | int len = 0; |
3387 | len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true); |
3388 | |
3389 | if (len < 0) |
3390 | return len; |
3391 | *ctxlen = len; |
3392 | return 0; |
3393 | } |
3394 | |
3395 | struct security_operations smack_ops = { |
3396 | .name = "smack", |
3397 | |
3398 | .ptrace_access_check = smack_ptrace_access_check, |
3399 | .ptrace_traceme = smack_ptrace_traceme, |
3400 | .syslog = smack_syslog, |
3401 | |
3402 | .sb_alloc_security = smack_sb_alloc_security, |
3403 | .sb_free_security = smack_sb_free_security, |
3404 | .sb_copy_data = smack_sb_copy_data, |
3405 | .sb_kern_mount = smack_sb_kern_mount, |
3406 | .sb_statfs = smack_sb_statfs, |
3407 | .sb_mount = smack_sb_mount, |
3408 | .sb_umount = smack_sb_umount, |
3409 | |
3410 | .bprm_set_creds = smack_bprm_set_creds, |
3411 | |
3412 | .inode_alloc_security = smack_inode_alloc_security, |
3413 | .inode_free_security = smack_inode_free_security, |
3414 | .inode_init_security = smack_inode_init_security, |
3415 | .inode_link = smack_inode_link, |
3416 | .inode_unlink = smack_inode_unlink, |
3417 | .inode_rmdir = smack_inode_rmdir, |
3418 | .inode_rename = smack_inode_rename, |
3419 | .inode_permission = smack_inode_permission, |
3420 | .inode_setattr = smack_inode_setattr, |
3421 | .inode_getattr = smack_inode_getattr, |
3422 | .inode_setxattr = smack_inode_setxattr, |
3423 | .inode_post_setxattr = smack_inode_post_setxattr, |
3424 | .inode_getxattr = smack_inode_getxattr, |
3425 | .inode_removexattr = smack_inode_removexattr, |
3426 | .inode_getsecurity = smack_inode_getsecurity, |
3427 | .inode_setsecurity = smack_inode_setsecurity, |
3428 | .inode_listsecurity = smack_inode_listsecurity, |
3429 | .inode_getsecid = smack_inode_getsecid, |
3430 | |
3431 | .file_permission = smack_file_permission, |
3432 | .file_alloc_security = smack_file_alloc_security, |
3433 | .file_free_security = smack_file_free_security, |
3434 | .file_ioctl = smack_file_ioctl, |
3435 | .file_lock = smack_file_lock, |
3436 | .file_fcntl = smack_file_fcntl, |
3437 | .file_mmap = smack_file_mmap, |
3438 | .file_set_fowner = smack_file_set_fowner, |
3439 | .file_send_sigiotask = smack_file_send_sigiotask, |
3440 | .file_receive = smack_file_receive, |
3441 | |
3442 | .cred_alloc_blank = smack_cred_alloc_blank, |
3443 | .cred_free = smack_cred_free, |
3444 | .cred_prepare = smack_cred_prepare, |
3445 | .cred_transfer = smack_cred_transfer, |
3446 | .kernel_act_as = smack_kernel_act_as, |
3447 | .kernel_create_files_as = smack_kernel_create_files_as, |
3448 | .task_setpgid = smack_task_setpgid, |
3449 | .task_getpgid = smack_task_getpgid, |
3450 | .task_getsid = smack_task_getsid, |
3451 | .task_getsecid = smack_task_getsecid, |
3452 | .task_setnice = smack_task_setnice, |
3453 | .task_setioprio = smack_task_setioprio, |
3454 | .task_getioprio = smack_task_getioprio, |
3455 | .task_setscheduler = smack_task_setscheduler, |
3456 | .task_getscheduler = smack_task_getscheduler, |
3457 | .task_movememory = smack_task_movememory, |
3458 | .task_kill = smack_task_kill, |
3459 | .task_wait = smack_task_wait, |
3460 | .task_to_inode = smack_task_to_inode, |
3461 | |
3462 | .ipc_permission = smack_ipc_permission, |
3463 | .ipc_getsecid = smack_ipc_getsecid, |
3464 | |
3465 | .msg_msg_alloc_security = smack_msg_msg_alloc_security, |
3466 | .msg_msg_free_security = smack_msg_msg_free_security, |
3467 | |
3468 | .msg_queue_alloc_security = smack_msg_queue_alloc_security, |
3469 | .msg_queue_free_security = smack_msg_queue_free_security, |
3470 | .msg_queue_associate = smack_msg_queue_associate, |
3471 | .msg_queue_msgctl = smack_msg_queue_msgctl, |
3472 | .msg_queue_msgsnd = smack_msg_queue_msgsnd, |
3473 | .msg_queue_msgrcv = smack_msg_queue_msgrcv, |
3474 | |
3475 | .shm_alloc_security = smack_shm_alloc_security, |
3476 | .shm_free_security = smack_shm_free_security, |
3477 | .shm_associate = smack_shm_associate, |
3478 | .shm_shmctl = smack_shm_shmctl, |
3479 | .shm_shmat = smack_shm_shmat, |
3480 | |
3481 | .sem_alloc_security = smack_sem_alloc_security, |
3482 | .sem_free_security = smack_sem_free_security, |
3483 | .sem_associate = smack_sem_associate, |
3484 | .sem_semctl = smack_sem_semctl, |
3485 | .sem_semop = smack_sem_semop, |
3486 | |
3487 | .d_instantiate = smack_d_instantiate, |
3488 | |
3489 | .getprocattr = smack_getprocattr, |
3490 | .setprocattr = smack_setprocattr, |
3491 | |
3492 | .unix_stream_connect = smack_unix_stream_connect, |
3493 | .unix_may_send = smack_unix_may_send, |
3494 | |
3495 | .socket_post_create = smack_socket_post_create, |
3496 | .socket_connect = smack_socket_connect, |
3497 | .socket_sendmsg = smack_socket_sendmsg, |
3498 | .socket_sock_rcv_skb = smack_socket_sock_rcv_skb, |
3499 | .socket_getpeersec_stream = smack_socket_getpeersec_stream, |
3500 | .socket_getpeersec_dgram = smack_socket_getpeersec_dgram, |
3501 | .sk_alloc_security = smack_sk_alloc_security, |
3502 | .sk_free_security = smack_sk_free_security, |
3503 | .sock_graft = smack_sock_graft, |
3504 | .inet_conn_request = smack_inet_conn_request, |
3505 | .inet_csk_clone = smack_inet_csk_clone, |
3506 | |
3507 | /* key management security hooks */ |
3508 | #ifdef CONFIG_KEYS |
3509 | .key_alloc = smack_key_alloc, |
3510 | .key_free = smack_key_free, |
3511 | .key_permission = smack_key_permission, |
3512 | #endif /* CONFIG_KEYS */ |
3513 | |
3514 | /* Audit hooks */ |
3515 | #ifdef CONFIG_AUDIT |
3516 | .audit_rule_init = smack_audit_rule_init, |
3517 | .audit_rule_known = smack_audit_rule_known, |
3518 | .audit_rule_match = smack_audit_rule_match, |
3519 | .audit_rule_free = smack_audit_rule_free, |
3520 | #endif /* CONFIG_AUDIT */ |
3521 | |
3522 | .secid_to_secctx = smack_secid_to_secctx, |
3523 | .secctx_to_secid = smack_secctx_to_secid, |
3524 | .release_secctx = smack_release_secctx, |
3525 | .inode_notifysecctx = smack_inode_notifysecctx, |
3526 | .inode_setsecctx = smack_inode_setsecctx, |
3527 | .inode_getsecctx = smack_inode_getsecctx, |
3528 | }; |
3529 | |
3530 | |
3531 | static __init void init_smack_know_list(void) |
3532 | { |
3533 | list_add(&smack_known_huh.list, &smack_known_list); |
3534 | list_add(&smack_known_hat.list, &smack_known_list); |
3535 | list_add(&smack_known_star.list, &smack_known_list); |
3536 | list_add(&smack_known_floor.list, &smack_known_list); |
3537 | list_add(&smack_known_invalid.list, &smack_known_list); |
3538 | list_add(&smack_known_web.list, &smack_known_list); |
3539 | } |
3540 | |
3541 | /** |
3542 | * smack_init - initialize the smack system |
3543 | * |
3544 | * Returns 0 |
3545 | */ |
3546 | static __init int smack_init(void) |
3547 | { |
3548 | struct cred *cred; |
3549 | struct task_smack *tsp; |
3550 | |
3551 | if (!security_module_enable(&smack_ops)) |
3552 | return 0; |
3553 | |
3554 | tsp = new_task_smack(smack_known_floor.smk_known, |
3555 | smack_known_floor.smk_known, GFP_KERNEL); |
3556 | if (tsp == NULL) |
3557 | return -ENOMEM; |
3558 | |
3559 | printk(KERN_INFO "Smack: Initializing.\n"); |
3560 | |
3561 | /* |
3562 | * Set the security state for the initial task. |
3563 | */ |
3564 | cred = (struct cred *) current->cred; |
3565 | cred->security = tsp; |
3566 | |
3567 | /* initialize the smack_know_list */ |
3568 | init_smack_know_list(); |
3569 | /* |
3570 | * Initialize locks |
3571 | */ |
3572 | spin_lock_init(&smack_known_huh.smk_cipsolock); |
3573 | spin_lock_init(&smack_known_hat.smk_cipsolock); |
3574 | spin_lock_init(&smack_known_star.smk_cipsolock); |
3575 | spin_lock_init(&smack_known_floor.smk_cipsolock); |
3576 | spin_lock_init(&smack_known_invalid.smk_cipsolock); |
3577 | |
3578 | /* |
3579 | * Register with LSM |
3580 | */ |
3581 | if (register_security(&smack_ops)) |
3582 | panic("smack: Unable to register with kernel.\n"); |
3583 | |
3584 | return 0; |
3585 | } |
3586 | |
3587 | /* |
3588 | * Smack requires early initialization in order to label |
3589 | * all processes and objects when they are created. |
3590 | */ |
3591 | security_initcall(smack_init); |
3592 |
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