Commit | Line | Data |
---|---|---|
e114e473 CS |
1 | /* |
2 | * Simplified MAC Kernel (smack) security module | |
3 | * | |
4 | * This file contains the smack hook function implementations. | |
5 | * | |
6 | * Author: | |
7 | * Casey Schaufler <casey@schaufler-ca.com> | |
8 | * | |
9 | * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License version 2, | |
13 | * as published by the Free Software Foundation. | |
14 | */ | |
15 | ||
16 | #include <linux/xattr.h> | |
17 | #include <linux/pagemap.h> | |
18 | #include <linux/mount.h> | |
19 | #include <linux/stat.h> | |
20 | #include <linux/ext2_fs.h> | |
21 | #include <linux/kd.h> | |
22 | #include <asm/ioctls.h> | |
23 | #include <linux/tcp.h> | |
24 | #include <linux/udp.h> | |
25 | #include <linux/mutex.h> | |
26 | #include <linux/pipe_fs_i.h> | |
27 | #include <net/netlabel.h> | |
28 | #include <net/cipso_ipv4.h> | |
d20bdda6 | 29 | #include <linux/audit.h> |
e114e473 CS |
30 | |
31 | #include "smack.h" | |
32 | ||
c69e8d9c DH |
33 | #define task_security(task) (task_cred_xxx((task), security)) |
34 | ||
e114e473 CS |
35 | /* |
36 | * I hope these are the hokeyist lines of code in the module. Casey. | |
37 | */ | |
38 | #define DEVPTS_SUPER_MAGIC 0x1cd1 | |
39 | #define SOCKFS_MAGIC 0x534F434B | |
40 | #define TMPFS_MAGIC 0x01021994 | |
41 | ||
42 | /** | |
43 | * smk_fetch - Fetch the smack label from a file. | |
44 | * @ip: a pointer to the inode | |
45 | * @dp: a pointer to the dentry | |
46 | * | |
47 | * Returns a pointer to the master list entry for the Smack label | |
48 | * or NULL if there was no label to fetch. | |
49 | */ | |
50 | static char *smk_fetch(struct inode *ip, struct dentry *dp) | |
51 | { | |
52 | int rc; | |
53 | char in[SMK_LABELLEN]; | |
54 | ||
55 | if (ip->i_op->getxattr == NULL) | |
56 | return NULL; | |
57 | ||
58 | rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN); | |
59 | if (rc < 0) | |
60 | return NULL; | |
61 | ||
62 | return smk_import(in, rc); | |
63 | } | |
64 | ||
65 | /** | |
66 | * new_inode_smack - allocate an inode security blob | |
67 | * @smack: a pointer to the Smack label to use in the blob | |
68 | * | |
69 | * Returns the new blob or NULL if there's no memory available | |
70 | */ | |
71 | struct inode_smack *new_inode_smack(char *smack) | |
72 | { | |
73 | struct inode_smack *isp; | |
74 | ||
75 | isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL); | |
76 | if (isp == NULL) | |
77 | return NULL; | |
78 | ||
79 | isp->smk_inode = smack; | |
80 | isp->smk_flags = 0; | |
81 | mutex_init(&isp->smk_lock); | |
82 | ||
83 | return isp; | |
84 | } | |
85 | ||
86 | /* | |
87 | * LSM hooks. | |
88 | * We he, that is fun! | |
89 | */ | |
90 | ||
91 | /** | |
5cd9c58f | 92 | * smack_ptrace_may_access - Smack approval on PTRACE_ATTACH |
e114e473 | 93 | * @ctp: child task pointer |
251a2a95 | 94 | * @mode: ptrace attachment mode |
e114e473 CS |
95 | * |
96 | * Returns 0 if access is OK, an error code otherwise | |
97 | * | |
98 | * Do the capability checks, and require read and write. | |
99 | */ | |
5cd9c58f | 100 | static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) |
e114e473 CS |
101 | { |
102 | int rc; | |
103 | ||
5cd9c58f | 104 | rc = cap_ptrace_may_access(ctp, mode); |
e114e473 CS |
105 | if (rc != 0) |
106 | return rc; | |
107 | ||
d84f4f99 | 108 | rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE); |
5cd9c58f | 109 | if (rc != 0 && capable(CAP_MAC_OVERRIDE)) |
e114e473 | 110 | return 0; |
5cd9c58f DH |
111 | return rc; |
112 | } | |
113 | ||
114 | /** | |
115 | * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME | |
116 | * @ptp: parent task pointer | |
117 | * | |
118 | * Returns 0 if access is OK, an error code otherwise | |
119 | * | |
120 | * Do the capability checks, and require read and write. | |
121 | */ | |
122 | static int smack_ptrace_traceme(struct task_struct *ptp) | |
123 | { | |
124 | int rc; | |
125 | ||
126 | rc = cap_ptrace_traceme(ptp); | |
127 | if (rc != 0) | |
128 | return rc; | |
e114e473 | 129 | |
d84f4f99 | 130 | rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE); |
5cd9c58f DH |
131 | if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE)) |
132 | return 0; | |
e114e473 CS |
133 | return rc; |
134 | } | |
135 | ||
136 | /** | |
137 | * smack_syslog - Smack approval on syslog | |
138 | * @type: message type | |
139 | * | |
140 | * Require that the task has the floor label | |
141 | * | |
142 | * Returns 0 on success, error code otherwise. | |
143 | */ | |
144 | static int smack_syslog(int type) | |
145 | { | |
146 | int rc; | |
86a264ab | 147 | char *sp = current_security(); |
e114e473 CS |
148 | |
149 | rc = cap_syslog(type); | |
150 | if (rc != 0) | |
151 | return rc; | |
152 | ||
153 | if (capable(CAP_MAC_OVERRIDE)) | |
154 | return 0; | |
155 | ||
156 | if (sp != smack_known_floor.smk_known) | |
157 | rc = -EACCES; | |
158 | ||
159 | return rc; | |
160 | } | |
161 | ||
162 | ||
163 | /* | |
164 | * Superblock Hooks. | |
165 | */ | |
166 | ||
167 | /** | |
168 | * smack_sb_alloc_security - allocate a superblock blob | |
169 | * @sb: the superblock getting the blob | |
170 | * | |
171 | * Returns 0 on success or -ENOMEM on error. | |
172 | */ | |
173 | static int smack_sb_alloc_security(struct super_block *sb) | |
174 | { | |
175 | struct superblock_smack *sbsp; | |
176 | ||
177 | sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL); | |
178 | ||
179 | if (sbsp == NULL) | |
180 | return -ENOMEM; | |
181 | ||
182 | sbsp->smk_root = smack_known_floor.smk_known; | |
183 | sbsp->smk_default = smack_known_floor.smk_known; | |
184 | sbsp->smk_floor = smack_known_floor.smk_known; | |
185 | sbsp->smk_hat = smack_known_hat.smk_known; | |
186 | sbsp->smk_initialized = 0; | |
187 | spin_lock_init(&sbsp->smk_sblock); | |
188 | ||
189 | sb->s_security = sbsp; | |
190 | ||
191 | return 0; | |
192 | } | |
193 | ||
194 | /** | |
195 | * smack_sb_free_security - free a superblock blob | |
196 | * @sb: the superblock getting the blob | |
197 | * | |
198 | */ | |
199 | static void smack_sb_free_security(struct super_block *sb) | |
200 | { | |
201 | kfree(sb->s_security); | |
202 | sb->s_security = NULL; | |
203 | } | |
204 | ||
205 | /** | |
206 | * smack_sb_copy_data - copy mount options data for processing | |
e114e473 | 207 | * @orig: where to start |
251a2a95 | 208 | * @smackopts: mount options string |
e114e473 CS |
209 | * |
210 | * Returns 0 on success or -ENOMEM on error. | |
211 | * | |
212 | * Copy the Smack specific mount options out of the mount | |
213 | * options list. | |
214 | */ | |
e0007529 | 215 | static int smack_sb_copy_data(char *orig, char *smackopts) |
e114e473 CS |
216 | { |
217 | char *cp, *commap, *otheropts, *dp; | |
218 | ||
e114e473 CS |
219 | otheropts = (char *)get_zeroed_page(GFP_KERNEL); |
220 | if (otheropts == NULL) | |
221 | return -ENOMEM; | |
222 | ||
223 | for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) { | |
224 | if (strstr(cp, SMK_FSDEFAULT) == cp) | |
225 | dp = smackopts; | |
226 | else if (strstr(cp, SMK_FSFLOOR) == cp) | |
227 | dp = smackopts; | |
228 | else if (strstr(cp, SMK_FSHAT) == cp) | |
229 | dp = smackopts; | |
230 | else if (strstr(cp, SMK_FSROOT) == cp) | |
231 | dp = smackopts; | |
232 | else | |
233 | dp = otheropts; | |
234 | ||
235 | commap = strchr(cp, ','); | |
236 | if (commap != NULL) | |
237 | *commap = '\0'; | |
238 | ||
239 | if (*dp != '\0') | |
240 | strcat(dp, ","); | |
241 | strcat(dp, cp); | |
242 | } | |
243 | ||
244 | strcpy(orig, otheropts); | |
245 | free_page((unsigned long)otheropts); | |
246 | ||
247 | return 0; | |
248 | } | |
249 | ||
250 | /** | |
251 | * smack_sb_kern_mount - Smack specific mount processing | |
252 | * @sb: the file system superblock | |
12204e24 | 253 | * @flags: the mount flags |
e114e473 CS |
254 | * @data: the smack mount options |
255 | * | |
256 | * Returns 0 on success, an error code on failure | |
257 | */ | |
12204e24 | 258 | static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) |
e114e473 CS |
259 | { |
260 | struct dentry *root = sb->s_root; | |
261 | struct inode *inode = root->d_inode; | |
262 | struct superblock_smack *sp = sb->s_security; | |
263 | struct inode_smack *isp; | |
264 | char *op; | |
265 | char *commap; | |
266 | char *nsp; | |
267 | ||
268 | spin_lock(&sp->smk_sblock); | |
269 | if (sp->smk_initialized != 0) { | |
270 | spin_unlock(&sp->smk_sblock); | |
271 | return 0; | |
272 | } | |
273 | sp->smk_initialized = 1; | |
274 | spin_unlock(&sp->smk_sblock); | |
275 | ||
276 | for (op = data; op != NULL; op = commap) { | |
277 | commap = strchr(op, ','); | |
278 | if (commap != NULL) | |
279 | *commap++ = '\0'; | |
280 | ||
281 | if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) { | |
282 | op += strlen(SMK_FSHAT); | |
283 | nsp = smk_import(op, 0); | |
284 | if (nsp != NULL) | |
285 | sp->smk_hat = nsp; | |
286 | } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) { | |
287 | op += strlen(SMK_FSFLOOR); | |
288 | nsp = smk_import(op, 0); | |
289 | if (nsp != NULL) | |
290 | sp->smk_floor = nsp; | |
291 | } else if (strncmp(op, SMK_FSDEFAULT, | |
292 | strlen(SMK_FSDEFAULT)) == 0) { | |
293 | op += strlen(SMK_FSDEFAULT); | |
294 | nsp = smk_import(op, 0); | |
295 | if (nsp != NULL) | |
296 | sp->smk_default = nsp; | |
297 | } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) { | |
298 | op += strlen(SMK_FSROOT); | |
299 | nsp = smk_import(op, 0); | |
300 | if (nsp != NULL) | |
301 | sp->smk_root = nsp; | |
302 | } | |
303 | } | |
304 | ||
305 | /* | |
306 | * Initialize the root inode. | |
307 | */ | |
308 | isp = inode->i_security; | |
309 | if (isp == NULL) | |
310 | inode->i_security = new_inode_smack(sp->smk_root); | |
311 | else | |
312 | isp->smk_inode = sp->smk_root; | |
313 | ||
314 | return 0; | |
315 | } | |
316 | ||
317 | /** | |
318 | * smack_sb_statfs - Smack check on statfs | |
319 | * @dentry: identifies the file system in question | |
320 | * | |
321 | * Returns 0 if current can read the floor of the filesystem, | |
322 | * and error code otherwise | |
323 | */ | |
324 | static int smack_sb_statfs(struct dentry *dentry) | |
325 | { | |
326 | struct superblock_smack *sbp = dentry->d_sb->s_security; | |
327 | ||
328 | return smk_curacc(sbp->smk_floor, MAY_READ); | |
329 | } | |
330 | ||
331 | /** | |
332 | * smack_sb_mount - Smack check for mounting | |
333 | * @dev_name: unused | |
251a2a95 | 334 | * @path: mount point |
e114e473 CS |
335 | * @type: unused |
336 | * @flags: unused | |
337 | * @data: unused | |
338 | * | |
339 | * Returns 0 if current can write the floor of the filesystem | |
340 | * being mounted on, an error code otherwise. | |
341 | */ | |
b5266eb4 | 342 | static int smack_sb_mount(char *dev_name, struct path *path, |
e114e473 CS |
343 | char *type, unsigned long flags, void *data) |
344 | { | |
b5266eb4 | 345 | struct superblock_smack *sbp = path->mnt->mnt_sb->s_security; |
e114e473 CS |
346 | |
347 | return smk_curacc(sbp->smk_floor, MAY_WRITE); | |
348 | } | |
349 | ||
350 | /** | |
351 | * smack_sb_umount - Smack check for unmounting | |
352 | * @mnt: file system to unmount | |
353 | * @flags: unused | |
354 | * | |
355 | * Returns 0 if current can write the floor of the filesystem | |
356 | * being unmounted, an error code otherwise. | |
357 | */ | |
358 | static int smack_sb_umount(struct vfsmount *mnt, int flags) | |
359 | { | |
360 | struct superblock_smack *sbp; | |
361 | ||
362 | sbp = mnt->mnt_sb->s_security; | |
363 | ||
364 | return smk_curacc(sbp->smk_floor, MAY_WRITE); | |
365 | } | |
366 | ||
367 | /* | |
368 | * Inode hooks | |
369 | */ | |
370 | ||
371 | /** | |
372 | * smack_inode_alloc_security - allocate an inode blob | |
251a2a95 | 373 | * @inode: the inode in need of a blob |
e114e473 CS |
374 | * |
375 | * Returns 0 if it gets a blob, -ENOMEM otherwise | |
376 | */ | |
377 | static int smack_inode_alloc_security(struct inode *inode) | |
378 | { | |
86a264ab | 379 | inode->i_security = new_inode_smack(current_security()); |
e114e473 CS |
380 | if (inode->i_security == NULL) |
381 | return -ENOMEM; | |
382 | return 0; | |
383 | } | |
384 | ||
385 | /** | |
386 | * smack_inode_free_security - free an inode blob | |
251a2a95 | 387 | * @inode: the inode with a blob |
e114e473 CS |
388 | * |
389 | * Clears the blob pointer in inode | |
390 | */ | |
391 | static void smack_inode_free_security(struct inode *inode) | |
392 | { | |
393 | kfree(inode->i_security); | |
394 | inode->i_security = NULL; | |
395 | } | |
396 | ||
397 | /** | |
398 | * smack_inode_init_security - copy out the smack from an inode | |
399 | * @inode: the inode | |
400 | * @dir: unused | |
401 | * @name: where to put the attribute name | |
402 | * @value: where to put the attribute value | |
403 | * @len: where to put the length of the attribute | |
404 | * | |
405 | * Returns 0 if it all works out, -ENOMEM if there's no memory | |
406 | */ | |
407 | static int smack_inode_init_security(struct inode *inode, struct inode *dir, | |
408 | char **name, void **value, size_t *len) | |
409 | { | |
410 | char *isp = smk_of_inode(inode); | |
411 | ||
412 | if (name) { | |
413 | *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); | |
414 | if (*name == NULL) | |
415 | return -ENOMEM; | |
416 | } | |
417 | ||
418 | if (value) { | |
419 | *value = kstrdup(isp, GFP_KERNEL); | |
420 | if (*value == NULL) | |
421 | return -ENOMEM; | |
422 | } | |
423 | ||
424 | if (len) | |
425 | *len = strlen(isp) + 1; | |
426 | ||
427 | return 0; | |
428 | } | |
429 | ||
430 | /** | |
431 | * smack_inode_link - Smack check on link | |
432 | * @old_dentry: the existing object | |
433 | * @dir: unused | |
434 | * @new_dentry: the new object | |
435 | * | |
436 | * Returns 0 if access is permitted, an error code otherwise | |
437 | */ | |
438 | static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, | |
439 | struct dentry *new_dentry) | |
440 | { | |
441 | int rc; | |
442 | char *isp; | |
443 | ||
444 | isp = smk_of_inode(old_dentry->d_inode); | |
445 | rc = smk_curacc(isp, MAY_WRITE); | |
446 | ||
447 | if (rc == 0 && new_dentry->d_inode != NULL) { | |
448 | isp = smk_of_inode(new_dentry->d_inode); | |
449 | rc = smk_curacc(isp, MAY_WRITE); | |
450 | } | |
451 | ||
452 | return rc; | |
453 | } | |
454 | ||
455 | /** | |
456 | * smack_inode_unlink - Smack check on inode deletion | |
457 | * @dir: containing directory object | |
458 | * @dentry: file to unlink | |
459 | * | |
460 | * Returns 0 if current can write the containing directory | |
461 | * and the object, error code otherwise | |
462 | */ | |
463 | static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) | |
464 | { | |
465 | struct inode *ip = dentry->d_inode; | |
466 | int rc; | |
467 | ||
468 | /* | |
469 | * You need write access to the thing you're unlinking | |
470 | */ | |
471 | rc = smk_curacc(smk_of_inode(ip), MAY_WRITE); | |
472 | if (rc == 0) | |
473 | /* | |
474 | * You also need write access to the containing directory | |
475 | */ | |
476 | rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); | |
477 | ||
478 | return rc; | |
479 | } | |
480 | ||
481 | /** | |
482 | * smack_inode_rmdir - Smack check on directory deletion | |
483 | * @dir: containing directory object | |
484 | * @dentry: directory to unlink | |
485 | * | |
486 | * Returns 0 if current can write the containing directory | |
487 | * and the directory, error code otherwise | |
488 | */ | |
489 | static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) | |
490 | { | |
491 | int rc; | |
492 | ||
493 | /* | |
494 | * You need write access to the thing you're removing | |
495 | */ | |
496 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); | |
497 | if (rc == 0) | |
498 | /* | |
499 | * You also need write access to the containing directory | |
500 | */ | |
501 | rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); | |
502 | ||
503 | return rc; | |
504 | } | |
505 | ||
506 | /** | |
507 | * smack_inode_rename - Smack check on rename | |
508 | * @old_inode: the old directory | |
509 | * @old_dentry: unused | |
510 | * @new_inode: the new directory | |
511 | * @new_dentry: unused | |
512 | * | |
513 | * Read and write access is required on both the old and | |
514 | * new directories. | |
515 | * | |
516 | * Returns 0 if access is permitted, an error code otherwise | |
517 | */ | |
518 | static int smack_inode_rename(struct inode *old_inode, | |
519 | struct dentry *old_dentry, | |
520 | struct inode *new_inode, | |
521 | struct dentry *new_dentry) | |
522 | { | |
523 | int rc; | |
524 | char *isp; | |
525 | ||
526 | isp = smk_of_inode(old_dentry->d_inode); | |
527 | rc = smk_curacc(isp, MAY_READWRITE); | |
528 | ||
529 | if (rc == 0 && new_dentry->d_inode != NULL) { | |
530 | isp = smk_of_inode(new_dentry->d_inode); | |
531 | rc = smk_curacc(isp, MAY_READWRITE); | |
532 | } | |
533 | ||
534 | return rc; | |
535 | } | |
536 | ||
537 | /** | |
538 | * smack_inode_permission - Smack version of permission() | |
539 | * @inode: the inode in question | |
540 | * @mask: the access requested | |
e114e473 CS |
541 | * |
542 | * This is the important Smack hook. | |
543 | * | |
544 | * Returns 0 if access is permitted, -EACCES otherwise | |
545 | */ | |
b77b0646 | 546 | static int smack_inode_permission(struct inode *inode, int mask) |
e114e473 CS |
547 | { |
548 | /* | |
549 | * No permission to check. Existence test. Yup, it's there. | |
550 | */ | |
551 | if (mask == 0) | |
552 | return 0; | |
553 | ||
554 | return smk_curacc(smk_of_inode(inode), mask); | |
555 | } | |
556 | ||
557 | /** | |
558 | * smack_inode_setattr - Smack check for setting attributes | |
559 | * @dentry: the object | |
560 | * @iattr: for the force flag | |
561 | * | |
562 | * Returns 0 if access is permitted, an error code otherwise | |
563 | */ | |
564 | static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) | |
565 | { | |
566 | /* | |
567 | * Need to allow for clearing the setuid bit. | |
568 | */ | |
569 | if (iattr->ia_valid & ATTR_FORCE) | |
570 | return 0; | |
571 | ||
572 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); | |
573 | } | |
574 | ||
575 | /** | |
576 | * smack_inode_getattr - Smack check for getting attributes | |
577 | * @mnt: unused | |
578 | * @dentry: the object | |
579 | * | |
580 | * Returns 0 if access is permitted, an error code otherwise | |
581 | */ | |
582 | static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) | |
583 | { | |
584 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); | |
585 | } | |
586 | ||
587 | /** | |
588 | * smack_inode_setxattr - Smack check for setting xattrs | |
589 | * @dentry: the object | |
590 | * @name: name of the attribute | |
591 | * @value: unused | |
592 | * @size: unused | |
593 | * @flags: unused | |
594 | * | |
595 | * This protects the Smack attribute explicitly. | |
596 | * | |
597 | * Returns 0 if access is permitted, an error code otherwise | |
598 | */ | |
8f0cfa52 DH |
599 | static int smack_inode_setxattr(struct dentry *dentry, const char *name, |
600 | const void *value, size_t size, int flags) | |
e114e473 | 601 | { |
bcdca225 | 602 | int rc = 0; |
e114e473 | 603 | |
bcdca225 CS |
604 | if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
605 | strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || | |
606 | strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { | |
607 | if (!capable(CAP_MAC_ADMIN)) | |
608 | rc = -EPERM; | |
609 | } else | |
610 | rc = cap_inode_setxattr(dentry, name, value, size, flags); | |
611 | ||
612 | if (rc == 0) | |
613 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); | |
614 | ||
615 | return rc; | |
e114e473 CS |
616 | } |
617 | ||
618 | /** | |
619 | * smack_inode_post_setxattr - Apply the Smack update approved above | |
620 | * @dentry: object | |
621 | * @name: attribute name | |
622 | * @value: attribute value | |
623 | * @size: attribute size | |
624 | * @flags: unused | |
625 | * | |
626 | * Set the pointer in the inode blob to the entry found | |
627 | * in the master label list. | |
628 | */ | |
8f0cfa52 DH |
629 | static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, |
630 | const void *value, size_t size, int flags) | |
e114e473 CS |
631 | { |
632 | struct inode_smack *isp; | |
633 | char *nsp; | |
634 | ||
635 | /* | |
636 | * Not SMACK | |
637 | */ | |
638 | if (strcmp(name, XATTR_NAME_SMACK)) | |
639 | return; | |
640 | ||
641 | if (size >= SMK_LABELLEN) | |
642 | return; | |
643 | ||
644 | isp = dentry->d_inode->i_security; | |
645 | ||
646 | /* | |
647 | * No locking is done here. This is a pointer | |
648 | * assignment. | |
649 | */ | |
650 | nsp = smk_import(value, size); | |
651 | if (nsp != NULL) | |
652 | isp->smk_inode = nsp; | |
653 | else | |
654 | isp->smk_inode = smack_known_invalid.smk_known; | |
655 | ||
656 | return; | |
657 | } | |
658 | ||
659 | /* | |
660 | * smack_inode_getxattr - Smack check on getxattr | |
661 | * @dentry: the object | |
662 | * @name: unused | |
663 | * | |
664 | * Returns 0 if access is permitted, an error code otherwise | |
665 | */ | |
8f0cfa52 | 666 | static int smack_inode_getxattr(struct dentry *dentry, const char *name) |
e114e473 CS |
667 | { |
668 | return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); | |
669 | } | |
670 | ||
671 | /* | |
672 | * smack_inode_removexattr - Smack check on removexattr | |
673 | * @dentry: the object | |
674 | * @name: name of the attribute | |
675 | * | |
676 | * Removing the Smack attribute requires CAP_MAC_ADMIN | |
677 | * | |
678 | * Returns 0 if access is permitted, an error code otherwise | |
679 | */ | |
8f0cfa52 | 680 | static int smack_inode_removexattr(struct dentry *dentry, const char *name) |
e114e473 | 681 | { |
bcdca225 | 682 | int rc = 0; |
e114e473 | 683 | |
bcdca225 CS |
684 | if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
685 | strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || | |
686 | strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { | |
687 | if (!capable(CAP_MAC_ADMIN)) | |
688 | rc = -EPERM; | |
689 | } else | |
690 | rc = cap_inode_removexattr(dentry, name); | |
691 | ||
692 | if (rc == 0) | |
693 | rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); | |
694 | ||
695 | return rc; | |
e114e473 CS |
696 | } |
697 | ||
698 | /** | |
699 | * smack_inode_getsecurity - get smack xattrs | |
700 | * @inode: the object | |
701 | * @name: attribute name | |
702 | * @buffer: where to put the result | |
251a2a95 | 703 | * @alloc: unused |
e114e473 CS |
704 | * |
705 | * Returns the size of the attribute or an error code | |
706 | */ | |
707 | static int smack_inode_getsecurity(const struct inode *inode, | |
708 | const char *name, void **buffer, | |
709 | bool alloc) | |
710 | { | |
711 | struct socket_smack *ssp; | |
712 | struct socket *sock; | |
713 | struct super_block *sbp; | |
714 | struct inode *ip = (struct inode *)inode; | |
715 | char *isp; | |
716 | int ilen; | |
717 | int rc = 0; | |
718 | ||
719 | if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { | |
720 | isp = smk_of_inode(inode); | |
721 | ilen = strlen(isp) + 1; | |
722 | *buffer = isp; | |
723 | return ilen; | |
724 | } | |
725 | ||
726 | /* | |
727 | * The rest of the Smack xattrs are only on sockets. | |
728 | */ | |
729 | sbp = ip->i_sb; | |
730 | if (sbp->s_magic != SOCKFS_MAGIC) | |
731 | return -EOPNOTSUPP; | |
732 | ||
733 | sock = SOCKET_I(ip); | |
2e1d146a | 734 | if (sock == NULL || sock->sk == NULL) |
e114e473 CS |
735 | return -EOPNOTSUPP; |
736 | ||
737 | ssp = sock->sk->sk_security; | |
738 | ||
739 | if (strcmp(name, XATTR_SMACK_IPIN) == 0) | |
740 | isp = ssp->smk_in; | |
741 | else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) | |
742 | isp = ssp->smk_out; | |
743 | else | |
744 | return -EOPNOTSUPP; | |
745 | ||
746 | ilen = strlen(isp) + 1; | |
747 | if (rc == 0) { | |
748 | *buffer = isp; | |
749 | rc = ilen; | |
750 | } | |
751 | ||
752 | return rc; | |
753 | } | |
754 | ||
755 | ||
756 | /** | |
757 | * smack_inode_listsecurity - list the Smack attributes | |
758 | * @inode: the object | |
759 | * @buffer: where they go | |
760 | * @buffer_size: size of buffer | |
761 | * | |
762 | * Returns 0 on success, -EINVAL otherwise | |
763 | */ | |
764 | static int smack_inode_listsecurity(struct inode *inode, char *buffer, | |
765 | size_t buffer_size) | |
766 | { | |
767 | int len = strlen(XATTR_NAME_SMACK); | |
768 | ||
769 | if (buffer != NULL && len <= buffer_size) { | |
770 | memcpy(buffer, XATTR_NAME_SMACK, len); | |
771 | return len; | |
772 | } | |
773 | return -EINVAL; | |
774 | } | |
775 | ||
d20bdda6 AD |
776 | /** |
777 | * smack_inode_getsecid - Extract inode's security id | |
778 | * @inode: inode to extract the info from | |
779 | * @secid: where result will be saved | |
780 | */ | |
781 | static void smack_inode_getsecid(const struct inode *inode, u32 *secid) | |
782 | { | |
783 | struct inode_smack *isp = inode->i_security; | |
784 | ||
785 | *secid = smack_to_secid(isp->smk_inode); | |
786 | } | |
787 | ||
e114e473 CS |
788 | /* |
789 | * File Hooks | |
790 | */ | |
791 | ||
792 | /** | |
793 | * smack_file_permission - Smack check on file operations | |
794 | * @file: unused | |
795 | * @mask: unused | |
796 | * | |
797 | * Returns 0 | |
798 | * | |
799 | * Should access checks be done on each read or write? | |
800 | * UNICOS and SELinux say yes. | |
801 | * Trusted Solaris, Trusted Irix, and just about everyone else says no. | |
802 | * | |
803 | * I'll say no for now. Smack does not do the frequent | |
804 | * label changing that SELinux does. | |
805 | */ | |
806 | static int smack_file_permission(struct file *file, int mask) | |
807 | { | |
808 | return 0; | |
809 | } | |
810 | ||
811 | /** | |
812 | * smack_file_alloc_security - assign a file security blob | |
813 | * @file: the object | |
814 | * | |
815 | * The security blob for a file is a pointer to the master | |
816 | * label list, so no allocation is done. | |
817 | * | |
818 | * Returns 0 | |
819 | */ | |
820 | static int smack_file_alloc_security(struct file *file) | |
821 | { | |
86a264ab | 822 | file->f_security = current_security(); |
e114e473 CS |
823 | return 0; |
824 | } | |
825 | ||
826 | /** | |
827 | * smack_file_free_security - clear a file security blob | |
828 | * @file: the object | |
829 | * | |
830 | * The security blob for a file is a pointer to the master | |
831 | * label list, so no memory is freed. | |
832 | */ | |
833 | static void smack_file_free_security(struct file *file) | |
834 | { | |
835 | file->f_security = NULL; | |
836 | } | |
837 | ||
838 | /** | |
839 | * smack_file_ioctl - Smack check on ioctls | |
840 | * @file: the object | |
841 | * @cmd: what to do | |
842 | * @arg: unused | |
843 | * | |
844 | * Relies heavily on the correct use of the ioctl command conventions. | |
845 | * | |
846 | * Returns 0 if allowed, error code otherwise | |
847 | */ | |
848 | static int smack_file_ioctl(struct file *file, unsigned int cmd, | |
849 | unsigned long arg) | |
850 | { | |
851 | int rc = 0; | |
852 | ||
853 | if (_IOC_DIR(cmd) & _IOC_WRITE) | |
854 | rc = smk_curacc(file->f_security, MAY_WRITE); | |
855 | ||
856 | if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) | |
857 | rc = smk_curacc(file->f_security, MAY_READ); | |
858 | ||
859 | return rc; | |
860 | } | |
861 | ||
862 | /** | |
863 | * smack_file_lock - Smack check on file locking | |
864 | * @file: the object | |
251a2a95 | 865 | * @cmd: unused |
e114e473 CS |
866 | * |
867 | * Returns 0 if current has write access, error code otherwise | |
868 | */ | |
869 | static int smack_file_lock(struct file *file, unsigned int cmd) | |
870 | { | |
871 | return smk_curacc(file->f_security, MAY_WRITE); | |
872 | } | |
873 | ||
874 | /** | |
875 | * smack_file_fcntl - Smack check on fcntl | |
876 | * @file: the object | |
877 | * @cmd: what action to check | |
878 | * @arg: unused | |
879 | * | |
880 | * Returns 0 if current has access, error code otherwise | |
881 | */ | |
882 | static int smack_file_fcntl(struct file *file, unsigned int cmd, | |
883 | unsigned long arg) | |
884 | { | |
885 | int rc; | |
886 | ||
887 | switch (cmd) { | |
888 | case F_DUPFD: | |
889 | case F_GETFD: | |
890 | case F_GETFL: | |
891 | case F_GETLK: | |
892 | case F_GETOWN: | |
893 | case F_GETSIG: | |
894 | rc = smk_curacc(file->f_security, MAY_READ); | |
895 | break; | |
896 | case F_SETFD: | |
897 | case F_SETFL: | |
898 | case F_SETLK: | |
899 | case F_SETLKW: | |
900 | case F_SETOWN: | |
901 | case F_SETSIG: | |
902 | rc = smk_curacc(file->f_security, MAY_WRITE); | |
903 | break; | |
904 | default: | |
905 | rc = smk_curacc(file->f_security, MAY_READWRITE); | |
906 | } | |
907 | ||
908 | return rc; | |
909 | } | |
910 | ||
911 | /** | |
912 | * smack_file_set_fowner - set the file security blob value | |
913 | * @file: object in question | |
914 | * | |
915 | * Returns 0 | |
916 | * Further research may be required on this one. | |
917 | */ | |
918 | static int smack_file_set_fowner(struct file *file) | |
919 | { | |
86a264ab | 920 | file->f_security = current_security(); |
e114e473 CS |
921 | return 0; |
922 | } | |
923 | ||
924 | /** | |
925 | * smack_file_send_sigiotask - Smack on sigio | |
926 | * @tsk: The target task | |
927 | * @fown: the object the signal come from | |
928 | * @signum: unused | |
929 | * | |
930 | * Allow a privileged task to get signals even if it shouldn't | |
931 | * | |
932 | * Returns 0 if a subject with the object's smack could | |
933 | * write to the task, an error code otherwise. | |
934 | */ | |
935 | static int smack_file_send_sigiotask(struct task_struct *tsk, | |
936 | struct fown_struct *fown, int signum) | |
937 | { | |
938 | struct file *file; | |
939 | int rc; | |
940 | ||
941 | /* | |
942 | * struct fown_struct is never outside the context of a struct file | |
943 | */ | |
944 | file = container_of(fown, struct file, f_owner); | |
b6dff3ec | 945 | rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE); |
5cd9c58f | 946 | if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) |
e114e473 CS |
947 | return 0; |
948 | return rc; | |
949 | } | |
950 | ||
951 | /** | |
952 | * smack_file_receive - Smack file receive check | |
953 | * @file: the object | |
954 | * | |
955 | * Returns 0 if current has access, error code otherwise | |
956 | */ | |
957 | static int smack_file_receive(struct file *file) | |
958 | { | |
959 | int may = 0; | |
960 | ||
961 | /* | |
962 | * This code relies on bitmasks. | |
963 | */ | |
964 | if (file->f_mode & FMODE_READ) | |
965 | may = MAY_READ; | |
966 | if (file->f_mode & FMODE_WRITE) | |
967 | may |= MAY_WRITE; | |
968 | ||
969 | return smk_curacc(file->f_security, may); | |
970 | } | |
971 | ||
972 | /* | |
973 | * Task hooks | |
974 | */ | |
975 | ||
e114e473 | 976 | /** |
f1752eec DH |
977 | * smack_cred_free - "free" task-level security credentials |
978 | * @cred: the credentials in question | |
e114e473 CS |
979 | * |
980 | * Smack isn't using copies of blobs. Everyone | |
981 | * points to an immutable list. The blobs never go away. | |
982 | * There is no leak here. | |
983 | */ | |
f1752eec | 984 | static void smack_cred_free(struct cred *cred) |
e114e473 | 985 | { |
f1752eec | 986 | cred->security = NULL; |
e114e473 CS |
987 | } |
988 | ||
d84f4f99 DH |
989 | /** |
990 | * smack_cred_prepare - prepare new set of credentials for modification | |
991 | * @new: the new credentials | |
992 | * @old: the original credentials | |
993 | * @gfp: the atomicity of any memory allocations | |
994 | * | |
995 | * Prepare a new set of credentials for modification. | |
996 | */ | |
997 | static int smack_cred_prepare(struct cred *new, const struct cred *old, | |
998 | gfp_t gfp) | |
999 | { | |
1000 | new->security = old->security; | |
1001 | return 0; | |
1002 | } | |
1003 | ||
251a2a95 RD |
1004 | /** |
1005 | * smack_cred_commit - commit new credentials | |
d84f4f99 DH |
1006 | * @new: the new credentials |
1007 | * @old: the original credentials | |
1008 | */ | |
1009 | static void smack_cred_commit(struct cred *new, const struct cred *old) | |
1010 | { | |
1011 | } | |
1012 | ||
3a3b7ce9 DH |
1013 | /** |
1014 | * smack_kernel_act_as - Set the subjective context in a set of credentials | |
251a2a95 RD |
1015 | * @new: points to the set of credentials to be modified. |
1016 | * @secid: specifies the security ID to be set | |
3a3b7ce9 DH |
1017 | * |
1018 | * Set the security data for a kernel service. | |
1019 | */ | |
1020 | static int smack_kernel_act_as(struct cred *new, u32 secid) | |
1021 | { | |
1022 | char *smack = smack_from_secid(secid); | |
1023 | ||
1024 | if (smack == NULL) | |
1025 | return -EINVAL; | |
1026 | ||
1027 | new->security = smack; | |
1028 | return 0; | |
1029 | } | |
1030 | ||
1031 | /** | |
1032 | * smack_kernel_create_files_as - Set the file creation label in a set of creds | |
251a2a95 RD |
1033 | * @new: points to the set of credentials to be modified |
1034 | * @inode: points to the inode to use as a reference | |
3a3b7ce9 DH |
1035 | * |
1036 | * Set the file creation context in a set of credentials to the same | |
1037 | * as the objective context of the specified inode | |
1038 | */ | |
1039 | static int smack_kernel_create_files_as(struct cred *new, | |
1040 | struct inode *inode) | |
1041 | { | |
1042 | struct inode_smack *isp = inode->i_security; | |
1043 | ||
1044 | new->security = isp->smk_inode; | |
1045 | return 0; | |
1046 | } | |
1047 | ||
e114e473 CS |
1048 | /** |
1049 | * smack_task_setpgid - Smack check on setting pgid | |
1050 | * @p: the task object | |
1051 | * @pgid: unused | |
1052 | * | |
1053 | * Return 0 if write access is permitted | |
1054 | */ | |
1055 | static int smack_task_setpgid(struct task_struct *p, pid_t pgid) | |
1056 | { | |
c69e8d9c | 1057 | return smk_curacc(task_security(p), MAY_WRITE); |
e114e473 CS |
1058 | } |
1059 | ||
1060 | /** | |
1061 | * smack_task_getpgid - Smack access check for getpgid | |
1062 | * @p: the object task | |
1063 | * | |
1064 | * Returns 0 if current can read the object task, error code otherwise | |
1065 | */ | |
1066 | static int smack_task_getpgid(struct task_struct *p) | |
1067 | { | |
c69e8d9c | 1068 | return smk_curacc(task_security(p), MAY_READ); |
e114e473 CS |
1069 | } |
1070 | ||
1071 | /** | |
1072 | * smack_task_getsid - Smack access check for getsid | |
1073 | * @p: the object task | |
1074 | * | |
1075 | * Returns 0 if current can read the object task, error code otherwise | |
1076 | */ | |
1077 | static int smack_task_getsid(struct task_struct *p) | |
1078 | { | |
c69e8d9c | 1079 | return smk_curacc(task_security(p), MAY_READ); |
e114e473 CS |
1080 | } |
1081 | ||
1082 | /** | |
1083 | * smack_task_getsecid - get the secid of the task | |
1084 | * @p: the object task | |
1085 | * @secid: where to put the result | |
1086 | * | |
1087 | * Sets the secid to contain a u32 version of the smack label. | |
1088 | */ | |
1089 | static void smack_task_getsecid(struct task_struct *p, u32 *secid) | |
1090 | { | |
c69e8d9c | 1091 | *secid = smack_to_secid(task_security(p)); |
e114e473 CS |
1092 | } |
1093 | ||
1094 | /** | |
1095 | * smack_task_setnice - Smack check on setting nice | |
1096 | * @p: the task object | |
1097 | * @nice: unused | |
1098 | * | |
1099 | * Return 0 if write access is permitted | |
1100 | */ | |
1101 | static int smack_task_setnice(struct task_struct *p, int nice) | |
1102 | { | |
bcdca225 CS |
1103 | int rc; |
1104 | ||
1105 | rc = cap_task_setnice(p, nice); | |
1106 | if (rc == 0) | |
c69e8d9c | 1107 | rc = smk_curacc(task_security(p), MAY_WRITE); |
bcdca225 | 1108 | return rc; |
e114e473 CS |
1109 | } |
1110 | ||
1111 | /** | |
1112 | * smack_task_setioprio - Smack check on setting ioprio | |
1113 | * @p: the task object | |
1114 | * @ioprio: unused | |
1115 | * | |
1116 | * Return 0 if write access is permitted | |
1117 | */ | |
1118 | static int smack_task_setioprio(struct task_struct *p, int ioprio) | |
1119 | { | |
bcdca225 CS |
1120 | int rc; |
1121 | ||
1122 | rc = cap_task_setioprio(p, ioprio); | |
1123 | if (rc == 0) | |
c69e8d9c | 1124 | rc = smk_curacc(task_security(p), MAY_WRITE); |
bcdca225 | 1125 | return rc; |
e114e473 CS |
1126 | } |
1127 | ||
1128 | /** | |
1129 | * smack_task_getioprio - Smack check on reading ioprio | |
1130 | * @p: the task object | |
1131 | * | |
1132 | * Return 0 if read access is permitted | |
1133 | */ | |
1134 | static int smack_task_getioprio(struct task_struct *p) | |
1135 | { | |
c69e8d9c | 1136 | return smk_curacc(task_security(p), MAY_READ); |
e114e473 CS |
1137 | } |
1138 | ||
1139 | /** | |
1140 | * smack_task_setscheduler - Smack check on setting scheduler | |
1141 | * @p: the task object | |
1142 | * @policy: unused | |
1143 | * @lp: unused | |
1144 | * | |
1145 | * Return 0 if read access is permitted | |
1146 | */ | |
1147 | static int smack_task_setscheduler(struct task_struct *p, int policy, | |
1148 | struct sched_param *lp) | |
1149 | { | |
bcdca225 CS |
1150 | int rc; |
1151 | ||
1152 | rc = cap_task_setscheduler(p, policy, lp); | |
1153 | if (rc == 0) | |
c69e8d9c | 1154 | rc = smk_curacc(task_security(p), MAY_WRITE); |
bcdca225 | 1155 | return rc; |
e114e473 CS |
1156 | } |
1157 | ||
1158 | /** | |
1159 | * smack_task_getscheduler - Smack check on reading scheduler | |
1160 | * @p: the task object | |
1161 | * | |
1162 | * Return 0 if read access is permitted | |
1163 | */ | |
1164 | static int smack_task_getscheduler(struct task_struct *p) | |
1165 | { | |
c69e8d9c | 1166 | return smk_curacc(task_security(p), MAY_READ); |
e114e473 CS |
1167 | } |
1168 | ||
1169 | /** | |
1170 | * smack_task_movememory - Smack check on moving memory | |
1171 | * @p: the task object | |
1172 | * | |
1173 | * Return 0 if write access is permitted | |
1174 | */ | |
1175 | static int smack_task_movememory(struct task_struct *p) | |
1176 | { | |
c69e8d9c | 1177 | return smk_curacc(task_security(p), MAY_WRITE); |
e114e473 CS |
1178 | } |
1179 | ||
1180 | /** | |
1181 | * smack_task_kill - Smack check on signal delivery | |
1182 | * @p: the task object | |
1183 | * @info: unused | |
1184 | * @sig: unused | |
1185 | * @secid: identifies the smack to use in lieu of current's | |
1186 | * | |
1187 | * Return 0 if write access is permitted | |
1188 | * | |
1189 | * The secid behavior is an artifact of an SELinux hack | |
1190 | * in the USB code. Someday it may go away. | |
1191 | */ | |
1192 | static int smack_task_kill(struct task_struct *p, struct siginfo *info, | |
1193 | int sig, u32 secid) | |
1194 | { | |
e114e473 CS |
1195 | /* |
1196 | * Sending a signal requires that the sender | |
1197 | * can write the receiver. | |
1198 | */ | |
1199 | if (secid == 0) | |
c69e8d9c | 1200 | return smk_curacc(task_security(p), MAY_WRITE); |
e114e473 CS |
1201 | /* |
1202 | * If the secid isn't 0 we're dealing with some USB IO | |
1203 | * specific behavior. This is not clean. For one thing | |
1204 | * we can't take privilege into account. | |
1205 | */ | |
c69e8d9c | 1206 | return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE); |
e114e473 CS |
1207 | } |
1208 | ||
1209 | /** | |
1210 | * smack_task_wait - Smack access check for waiting | |
1211 | * @p: task to wait for | |
1212 | * | |
1213 | * Returns 0 if current can wait for p, error code otherwise | |
1214 | */ | |
1215 | static int smack_task_wait(struct task_struct *p) | |
1216 | { | |
1217 | int rc; | |
1218 | ||
c69e8d9c | 1219 | rc = smk_access(current_security(), task_security(p), MAY_WRITE); |
e114e473 CS |
1220 | if (rc == 0) |
1221 | return 0; | |
1222 | ||
1223 | /* | |
1224 | * Allow the operation to succeed if either task | |
1225 | * has privilege to perform operations that might | |
1226 | * account for the smack labels having gotten to | |
1227 | * be different in the first place. | |
1228 | * | |
5cd9c58f | 1229 | * This breaks the strict subject/object access |
e114e473 CS |
1230 | * control ideal, taking the object's privilege |
1231 | * state into account in the decision as well as | |
1232 | * the smack value. | |
1233 | */ | |
5cd9c58f | 1234 | if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE)) |
e114e473 CS |
1235 | return 0; |
1236 | ||
1237 | return rc; | |
1238 | } | |
1239 | ||
1240 | /** | |
1241 | * smack_task_to_inode - copy task smack into the inode blob | |
1242 | * @p: task to copy from | |
251a2a95 | 1243 | * @inode: inode to copy to |
e114e473 CS |
1244 | * |
1245 | * Sets the smack pointer in the inode security blob | |
1246 | */ | |
1247 | static void smack_task_to_inode(struct task_struct *p, struct inode *inode) | |
1248 | { | |
1249 | struct inode_smack *isp = inode->i_security; | |
c69e8d9c | 1250 | isp->smk_inode = task_security(p); |
e114e473 CS |
1251 | } |
1252 | ||
1253 | /* | |
1254 | * Socket hooks. | |
1255 | */ | |
1256 | ||
1257 | /** | |
1258 | * smack_sk_alloc_security - Allocate a socket blob | |
1259 | * @sk: the socket | |
1260 | * @family: unused | |
251a2a95 | 1261 | * @gfp_flags: memory allocation flags |
e114e473 CS |
1262 | * |
1263 | * Assign Smack pointers to current | |
1264 | * | |
1265 | * Returns 0 on success, -ENOMEM is there's no memory | |
1266 | */ | |
1267 | static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) | |
1268 | { | |
86a264ab | 1269 | char *csp = current_security(); |
e114e473 CS |
1270 | struct socket_smack *ssp; |
1271 | ||
1272 | ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); | |
1273 | if (ssp == NULL) | |
1274 | return -ENOMEM; | |
1275 | ||
1276 | ssp->smk_in = csp; | |
1277 | ssp->smk_out = csp; | |
6d3dc07c | 1278 | ssp->smk_labeled = SMACK_CIPSO_SOCKET; |
e114e473 CS |
1279 | ssp->smk_packet[0] = '\0'; |
1280 | ||
1281 | sk->sk_security = ssp; | |
1282 | ||
1283 | return 0; | |
1284 | } | |
1285 | ||
1286 | /** | |
1287 | * smack_sk_free_security - Free a socket blob | |
1288 | * @sk: the socket | |
1289 | * | |
1290 | * Clears the blob pointer | |
1291 | */ | |
1292 | static void smack_sk_free_security(struct sock *sk) | |
1293 | { | |
1294 | kfree(sk->sk_security); | |
1295 | } | |
1296 | ||
1297 | /** | |
1298 | * smack_set_catset - convert a capset to netlabel mls categories | |
1299 | * @catset: the Smack categories | |
1300 | * @sap: where to put the netlabel categories | |
1301 | * | |
1302 | * Allocates and fills attr.mls.cat | |
1303 | */ | |
1304 | static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap) | |
1305 | { | |
1306 | unsigned char *cp; | |
1307 | unsigned char m; | |
1308 | int cat; | |
1309 | int rc; | |
1310 | int byte; | |
1311 | ||
c60264c4 | 1312 | if (!catset) |
e114e473 CS |
1313 | return; |
1314 | ||
1315 | sap->flags |= NETLBL_SECATTR_MLS_CAT; | |
1316 | sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); | |
1317 | sap->attr.mls.cat->startbit = 0; | |
1318 | ||
1319 | for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++) | |
1320 | for (m = 0x80; m != 0; m >>= 1, cat++) { | |
1321 | if ((m & *cp) == 0) | |
1322 | continue; | |
1323 | rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat, | |
1324 | cat, GFP_ATOMIC); | |
1325 | } | |
1326 | } | |
1327 | ||
1328 | /** | |
1329 | * smack_to_secattr - fill a secattr from a smack value | |
1330 | * @smack: the smack value | |
1331 | * @nlsp: where the result goes | |
1332 | * | |
1333 | * Casey says that CIPSO is good enough for now. | |
1334 | * It can be used to effect. | |
1335 | * It can also be abused to effect when necessary. | |
1336 | * Appologies to the TSIG group in general and GW in particular. | |
1337 | */ | |
1338 | static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) | |
1339 | { | |
1340 | struct smack_cipso cipso; | |
1341 | int rc; | |
1342 | ||
6d3dc07c CS |
1343 | nlsp->domain = smack; |
1344 | nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; | |
e114e473 | 1345 | |
6d3dc07c CS |
1346 | rc = smack_to_cipso(smack, &cipso); |
1347 | if (rc == 0) { | |
1348 | nlsp->attr.mls.lvl = cipso.smk_level; | |
1349 | smack_set_catset(cipso.smk_catset, nlsp); | |
1350 | } else { | |
1351 | nlsp->attr.mls.lvl = smack_cipso_direct; | |
1352 | smack_set_catset(smack, nlsp); | |
e114e473 CS |
1353 | } |
1354 | } | |
1355 | ||
1356 | /** | |
1357 | * smack_netlabel - Set the secattr on a socket | |
1358 | * @sk: the socket | |
6d3dc07c | 1359 | * @labeled: socket label scheme |
e114e473 CS |
1360 | * |
1361 | * Convert the outbound smack value (smk_out) to a | |
1362 | * secattr and attach it to the socket. | |
1363 | * | |
1364 | * Returns 0 on success or an error code | |
1365 | */ | |
6d3dc07c | 1366 | static int smack_netlabel(struct sock *sk, int labeled) |
e114e473 | 1367 | { |
2e1d146a | 1368 | struct socket_smack *ssp; |
e114e473 | 1369 | struct netlbl_lsm_secattr secattr; |
6d3dc07c | 1370 | int rc = 0; |
e114e473 | 1371 | |
2e1d146a | 1372 | ssp = sk->sk_security; |
6d3dc07c CS |
1373 | /* |
1374 | * Usually the netlabel code will handle changing the | |
1375 | * packet labeling based on the label. | |
1376 | * The case of a single label host is different, because | |
1377 | * a single label host should never get a labeled packet | |
1378 | * even though the label is usually associated with a packet | |
1379 | * label. | |
1380 | */ | |
1381 | local_bh_disable(); | |
1382 | bh_lock_sock_nested(sk); | |
1383 | ||
1384 | if (ssp->smk_out == smack_net_ambient || | |
1385 | labeled == SMACK_UNLABELED_SOCKET) | |
1386 | netlbl_sock_delattr(sk); | |
1387 | else { | |
1388 | netlbl_secattr_init(&secattr); | |
1389 | smack_to_secattr(ssp->smk_out, &secattr); | |
389fb800 | 1390 | rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr); |
6d3dc07c CS |
1391 | netlbl_secattr_destroy(&secattr); |
1392 | } | |
1393 | ||
1394 | bh_unlock_sock(sk); | |
1395 | local_bh_enable(); | |
1396 | /* | |
1397 | * Remember the label scheme used so that it is not | |
1398 | * necessary to do the netlabel setting if it has not | |
1399 | * changed the next time through. | |
1400 | * | |
1401 | * The -EDESTADDRREQ case is an indication that there's | |
1402 | * a single level host involved. | |
1403 | */ | |
1404 | if (rc == 0) | |
1405 | ssp->smk_labeled = labeled; | |
4bc87e62 | 1406 | |
e114e473 CS |
1407 | return rc; |
1408 | } | |
1409 | ||
1410 | /** | |
1411 | * smack_inode_setsecurity - set smack xattrs | |
1412 | * @inode: the object | |
1413 | * @name: attribute name | |
1414 | * @value: attribute value | |
1415 | * @size: size of the attribute | |
1416 | * @flags: unused | |
1417 | * | |
1418 | * Sets the named attribute in the appropriate blob | |
1419 | * | |
1420 | * Returns 0 on success, or an error code | |
1421 | */ | |
1422 | static int smack_inode_setsecurity(struct inode *inode, const char *name, | |
1423 | const void *value, size_t size, int flags) | |
1424 | { | |
1425 | char *sp; | |
1426 | struct inode_smack *nsp = inode->i_security; | |
1427 | struct socket_smack *ssp; | |
1428 | struct socket *sock; | |
4bc87e62 | 1429 | int rc = 0; |
e114e473 CS |
1430 | |
1431 | if (value == NULL || size > SMK_LABELLEN) | |
1432 | return -EACCES; | |
1433 | ||
1434 | sp = smk_import(value, size); | |
1435 | if (sp == NULL) | |
1436 | return -EINVAL; | |
1437 | ||
1438 | if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { | |
1439 | nsp->smk_inode = sp; | |
1440 | return 0; | |
1441 | } | |
1442 | /* | |
1443 | * The rest of the Smack xattrs are only on sockets. | |
1444 | */ | |
1445 | if (inode->i_sb->s_magic != SOCKFS_MAGIC) | |
1446 | return -EOPNOTSUPP; | |
1447 | ||
1448 | sock = SOCKET_I(inode); | |
2e1d146a | 1449 | if (sock == NULL || sock->sk == NULL) |
e114e473 CS |
1450 | return -EOPNOTSUPP; |
1451 | ||
1452 | ssp = sock->sk->sk_security; | |
1453 | ||
1454 | if (strcmp(name, XATTR_SMACK_IPIN) == 0) | |
1455 | ssp->smk_in = sp; | |
1456 | else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { | |
1457 | ssp->smk_out = sp; | |
6d3dc07c | 1458 | rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
4bc87e62 CS |
1459 | if (rc != 0) |
1460 | printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", | |
1461 | __func__, -rc); | |
e114e473 CS |
1462 | } else |
1463 | return -EOPNOTSUPP; | |
1464 | ||
1465 | return 0; | |
1466 | } | |
1467 | ||
1468 | /** | |
1469 | * smack_socket_post_create - finish socket setup | |
1470 | * @sock: the socket | |
1471 | * @family: protocol family | |
1472 | * @type: unused | |
1473 | * @protocol: unused | |
1474 | * @kern: unused | |
1475 | * | |
1476 | * Sets the netlabel information on the socket | |
1477 | * | |
1478 | * Returns 0 on success, and error code otherwise | |
1479 | */ | |
1480 | static int smack_socket_post_create(struct socket *sock, int family, | |
1481 | int type, int protocol, int kern) | |
1482 | { | |
2e1d146a | 1483 | if (family != PF_INET || sock->sk == NULL) |
e114e473 CS |
1484 | return 0; |
1485 | /* | |
1486 | * Set the outbound netlbl. | |
1487 | */ | |
6d3dc07c CS |
1488 | return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
1489 | } | |
1490 | ||
1491 | ||
1492 | /** | |
1493 | * smack_host_label - check host based restrictions | |
1494 | * @sip: the object end | |
1495 | * | |
1496 | * looks for host based access restrictions | |
1497 | * | |
1498 | * This version will only be appropriate for really small | |
211a40c0 | 1499 | * sets of single label hosts. |
6d3dc07c CS |
1500 | * |
1501 | * Returns the label of the far end or NULL if it's not special. | |
1502 | */ | |
1503 | static char *smack_host_label(struct sockaddr_in *sip) | |
1504 | { | |
1505 | struct smk_netlbladdr *snp; | |
6d3dc07c | 1506 | struct in_addr *siap = &sip->sin_addr; |
6d3dc07c CS |
1507 | |
1508 | if (siap->s_addr == 0) | |
1509 | return NULL; | |
1510 | ||
7198e2ee EB |
1511 | rcu_read_lock(); |
1512 | list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) { | |
6d3dc07c | 1513 | /* |
211a40c0 | 1514 | * we break after finding the first match because |
1515 | * the list is sorted from longest to shortest mask | |
1516 | * so we have found the most specific match | |
6d3dc07c | 1517 | */ |
211a40c0 | 1518 | if ((&snp->smk_host.sin_addr)->s_addr == |
1519 | (siap->s_addr & (&snp->smk_mask)->s_addr)) { | |
7198e2ee | 1520 | rcu_read_unlock(); |
6d3dc07c | 1521 | return snp->smk_label; |
211a40c0 | 1522 | } |
6d3dc07c | 1523 | } |
7198e2ee | 1524 | rcu_read_unlock(); |
211a40c0 | 1525 | return NULL; |
6d3dc07c CS |
1526 | } |
1527 | ||
1528 | /** | |
1529 | * smack_socket_connect - connect access check | |
1530 | * @sock: the socket | |
1531 | * @sap: the other end | |
1532 | * @addrlen: size of sap | |
1533 | * | |
1534 | * Verifies that a connection may be possible | |
1535 | * | |
1536 | * Returns 0 on success, and error code otherwise | |
1537 | */ | |
1538 | static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, | |
1539 | int addrlen) | |
1540 | { | |
1541 | struct socket_smack *ssp = sock->sk->sk_security; | |
1542 | char *hostsp; | |
1543 | int rc; | |
1544 | ||
1545 | if (sock->sk == NULL || sock->sk->sk_family != PF_INET) | |
1546 | return 0; | |
1547 | ||
1548 | if (addrlen < sizeof(struct sockaddr_in)) | |
1549 | return -EINVAL; | |
1550 | ||
1551 | hostsp = smack_host_label((struct sockaddr_in *)sap); | |
1552 | if (hostsp == NULL) { | |
1553 | if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) | |
1554 | return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); | |
1555 | return 0; | |
1556 | } | |
1557 | ||
1558 | rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); | |
1559 | if (rc != 0) | |
1560 | return rc; | |
1561 | ||
1562 | if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) | |
1563 | return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); | |
1564 | return 0; | |
e114e473 CS |
1565 | } |
1566 | ||
1567 | /** | |
1568 | * smack_flags_to_may - convert S_ to MAY_ values | |
1569 | * @flags: the S_ value | |
1570 | * | |
1571 | * Returns the equivalent MAY_ value | |
1572 | */ | |
1573 | static int smack_flags_to_may(int flags) | |
1574 | { | |
1575 | int may = 0; | |
1576 | ||
1577 | if (flags & S_IRUGO) | |
1578 | may |= MAY_READ; | |
1579 | if (flags & S_IWUGO) | |
1580 | may |= MAY_WRITE; | |
1581 | if (flags & S_IXUGO) | |
1582 | may |= MAY_EXEC; | |
1583 | ||
1584 | return may; | |
1585 | } | |
1586 | ||
1587 | /** | |
1588 | * smack_msg_msg_alloc_security - Set the security blob for msg_msg | |
1589 | * @msg: the object | |
1590 | * | |
1591 | * Returns 0 | |
1592 | */ | |
1593 | static int smack_msg_msg_alloc_security(struct msg_msg *msg) | |
1594 | { | |
86a264ab | 1595 | msg->security = current_security(); |
e114e473 CS |
1596 | return 0; |
1597 | } | |
1598 | ||
1599 | /** | |
1600 | * smack_msg_msg_free_security - Clear the security blob for msg_msg | |
1601 | * @msg: the object | |
1602 | * | |
1603 | * Clears the blob pointer | |
1604 | */ | |
1605 | static void smack_msg_msg_free_security(struct msg_msg *msg) | |
1606 | { | |
1607 | msg->security = NULL; | |
1608 | } | |
1609 | ||
1610 | /** | |
1611 | * smack_of_shm - the smack pointer for the shm | |
1612 | * @shp: the object | |
1613 | * | |
1614 | * Returns a pointer to the smack value | |
1615 | */ | |
1616 | static char *smack_of_shm(struct shmid_kernel *shp) | |
1617 | { | |
1618 | return (char *)shp->shm_perm.security; | |
1619 | } | |
1620 | ||
1621 | /** | |
1622 | * smack_shm_alloc_security - Set the security blob for shm | |
1623 | * @shp: the object | |
1624 | * | |
1625 | * Returns 0 | |
1626 | */ | |
1627 | static int smack_shm_alloc_security(struct shmid_kernel *shp) | |
1628 | { | |
1629 | struct kern_ipc_perm *isp = &shp->shm_perm; | |
1630 | ||
86a264ab | 1631 | isp->security = current_security(); |
e114e473 CS |
1632 | return 0; |
1633 | } | |
1634 | ||
1635 | /** | |
1636 | * smack_shm_free_security - Clear the security blob for shm | |
1637 | * @shp: the object | |
1638 | * | |
1639 | * Clears the blob pointer | |
1640 | */ | |
1641 | static void smack_shm_free_security(struct shmid_kernel *shp) | |
1642 | { | |
1643 | struct kern_ipc_perm *isp = &shp->shm_perm; | |
1644 | ||
1645 | isp->security = NULL; | |
1646 | } | |
1647 | ||
1648 | /** | |
1649 | * smack_shm_associate - Smack access check for shm | |
1650 | * @shp: the object | |
1651 | * @shmflg: access requested | |
1652 | * | |
1653 | * Returns 0 if current has the requested access, error code otherwise | |
1654 | */ | |
1655 | static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) | |
1656 | { | |
1657 | char *ssp = smack_of_shm(shp); | |
1658 | int may; | |
1659 | ||
1660 | may = smack_flags_to_may(shmflg); | |
1661 | return smk_curacc(ssp, may); | |
1662 | } | |
1663 | ||
1664 | /** | |
1665 | * smack_shm_shmctl - Smack access check for shm | |
1666 | * @shp: the object | |
1667 | * @cmd: what it wants to do | |
1668 | * | |
1669 | * Returns 0 if current has the requested access, error code otherwise | |
1670 | */ | |
1671 | static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) | |
1672 | { | |
1d252fb8 | 1673 | char *ssp; |
e114e473 CS |
1674 | int may; |
1675 | ||
1676 | switch (cmd) { | |
1677 | case IPC_STAT: | |
1678 | case SHM_STAT: | |
1679 | may = MAY_READ; | |
1680 | break; | |
1681 | case IPC_SET: | |
1682 | case SHM_LOCK: | |
1683 | case SHM_UNLOCK: | |
1684 | case IPC_RMID: | |
1685 | may = MAY_READWRITE; | |
1686 | break; | |
1687 | case IPC_INFO: | |
1688 | case SHM_INFO: | |
1689 | /* | |
1690 | * System level information. | |
1691 | */ | |
1692 | return 0; | |
1693 | default: | |
1694 | return -EINVAL; | |
1695 | } | |
1696 | ||
1d252fb8 | 1697 | ssp = smack_of_shm(shp); |
e114e473 CS |
1698 | return smk_curacc(ssp, may); |
1699 | } | |
1700 | ||
1701 | /** | |
1702 | * smack_shm_shmat - Smack access for shmat | |
1703 | * @shp: the object | |
1704 | * @shmaddr: unused | |
1705 | * @shmflg: access requested | |
1706 | * | |
1707 | * Returns 0 if current has the requested access, error code otherwise | |
1708 | */ | |
1709 | static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, | |
1710 | int shmflg) | |
1711 | { | |
1712 | char *ssp = smack_of_shm(shp); | |
1713 | int may; | |
1714 | ||
1715 | may = smack_flags_to_may(shmflg); | |
1716 | return smk_curacc(ssp, may); | |
1717 | } | |
1718 | ||
1719 | /** | |
1720 | * smack_of_sem - the smack pointer for the sem | |
1721 | * @sma: the object | |
1722 | * | |
1723 | * Returns a pointer to the smack value | |
1724 | */ | |
1725 | static char *smack_of_sem(struct sem_array *sma) | |
1726 | { | |
1727 | return (char *)sma->sem_perm.security; | |
1728 | } | |
1729 | ||
1730 | /** | |
1731 | * smack_sem_alloc_security - Set the security blob for sem | |
1732 | * @sma: the object | |
1733 | * | |
1734 | * Returns 0 | |
1735 | */ | |
1736 | static int smack_sem_alloc_security(struct sem_array *sma) | |
1737 | { | |
1738 | struct kern_ipc_perm *isp = &sma->sem_perm; | |
1739 | ||
86a264ab | 1740 | isp->security = current_security(); |
e114e473 CS |
1741 | return 0; |
1742 | } | |
1743 | ||
1744 | /** | |
1745 | * smack_sem_free_security - Clear the security blob for sem | |
1746 | * @sma: the object | |
1747 | * | |
1748 | * Clears the blob pointer | |
1749 | */ | |
1750 | static void smack_sem_free_security(struct sem_array *sma) | |
1751 | { | |
1752 | struct kern_ipc_perm *isp = &sma->sem_perm; | |
1753 | ||
1754 | isp->security = NULL; | |
1755 | } | |
1756 | ||
1757 | /** | |
1758 | * smack_sem_associate - Smack access check for sem | |
1759 | * @sma: the object | |
1760 | * @semflg: access requested | |
1761 | * | |
1762 | * Returns 0 if current has the requested access, error code otherwise | |
1763 | */ | |
1764 | static int smack_sem_associate(struct sem_array *sma, int semflg) | |
1765 | { | |
1766 | char *ssp = smack_of_sem(sma); | |
1767 | int may; | |
1768 | ||
1769 | may = smack_flags_to_may(semflg); | |
1770 | return smk_curacc(ssp, may); | |
1771 | } | |
1772 | ||
1773 | /** | |
1774 | * smack_sem_shmctl - Smack access check for sem | |
1775 | * @sma: the object | |
1776 | * @cmd: what it wants to do | |
1777 | * | |
1778 | * Returns 0 if current has the requested access, error code otherwise | |
1779 | */ | |
1780 | static int smack_sem_semctl(struct sem_array *sma, int cmd) | |
1781 | { | |
1d252fb8 | 1782 | char *ssp; |
e114e473 CS |
1783 | int may; |
1784 | ||
1785 | switch (cmd) { | |
1786 | case GETPID: | |
1787 | case GETNCNT: | |
1788 | case GETZCNT: | |
1789 | case GETVAL: | |
1790 | case GETALL: | |
1791 | case IPC_STAT: | |
1792 | case SEM_STAT: | |
1793 | may = MAY_READ; | |
1794 | break; | |
1795 | case SETVAL: | |
1796 | case SETALL: | |
1797 | case IPC_RMID: | |
1798 | case IPC_SET: | |
1799 | may = MAY_READWRITE; | |
1800 | break; | |
1801 | case IPC_INFO: | |
1802 | case SEM_INFO: | |
1803 | /* | |
1804 | * System level information | |
1805 | */ | |
1806 | return 0; | |
1807 | default: | |
1808 | return -EINVAL; | |
1809 | } | |
1810 | ||
1d252fb8 | 1811 | ssp = smack_of_sem(sma); |
e114e473 CS |
1812 | return smk_curacc(ssp, may); |
1813 | } | |
1814 | ||
1815 | /** | |
1816 | * smack_sem_semop - Smack checks of semaphore operations | |
1817 | * @sma: the object | |
1818 | * @sops: unused | |
1819 | * @nsops: unused | |
1820 | * @alter: unused | |
1821 | * | |
1822 | * Treated as read and write in all cases. | |
1823 | * | |
1824 | * Returns 0 if access is allowed, error code otherwise | |
1825 | */ | |
1826 | static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, | |
1827 | unsigned nsops, int alter) | |
1828 | { | |
1829 | char *ssp = smack_of_sem(sma); | |
1830 | ||
1831 | return smk_curacc(ssp, MAY_READWRITE); | |
1832 | } | |
1833 | ||
1834 | /** | |
1835 | * smack_msg_alloc_security - Set the security blob for msg | |
1836 | * @msq: the object | |
1837 | * | |
1838 | * Returns 0 | |
1839 | */ | |
1840 | static int smack_msg_queue_alloc_security(struct msg_queue *msq) | |
1841 | { | |
1842 | struct kern_ipc_perm *kisp = &msq->q_perm; | |
1843 | ||
86a264ab | 1844 | kisp->security = current_security(); |
e114e473 CS |
1845 | return 0; |
1846 | } | |
1847 | ||
1848 | /** | |
1849 | * smack_msg_free_security - Clear the security blob for msg | |
1850 | * @msq: the object | |
1851 | * | |
1852 | * Clears the blob pointer | |
1853 | */ | |
1854 | static void smack_msg_queue_free_security(struct msg_queue *msq) | |
1855 | { | |
1856 | struct kern_ipc_perm *kisp = &msq->q_perm; | |
1857 | ||
1858 | kisp->security = NULL; | |
1859 | } | |
1860 | ||
1861 | /** | |
1862 | * smack_of_msq - the smack pointer for the msq | |
1863 | * @msq: the object | |
1864 | * | |
1865 | * Returns a pointer to the smack value | |
1866 | */ | |
1867 | static char *smack_of_msq(struct msg_queue *msq) | |
1868 | { | |
1869 | return (char *)msq->q_perm.security; | |
1870 | } | |
1871 | ||
1872 | /** | |
1873 | * smack_msg_queue_associate - Smack access check for msg_queue | |
1874 | * @msq: the object | |
1875 | * @msqflg: access requested | |
1876 | * | |
1877 | * Returns 0 if current has the requested access, error code otherwise | |
1878 | */ | |
1879 | static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) | |
1880 | { | |
1881 | char *msp = smack_of_msq(msq); | |
1882 | int may; | |
1883 | ||
1884 | may = smack_flags_to_may(msqflg); | |
1885 | return smk_curacc(msp, may); | |
1886 | } | |
1887 | ||
1888 | /** | |
1889 | * smack_msg_queue_msgctl - Smack access check for msg_queue | |
1890 | * @msq: the object | |
1891 | * @cmd: what it wants to do | |
1892 | * | |
1893 | * Returns 0 if current has the requested access, error code otherwise | |
1894 | */ | |
1895 | static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) | |
1896 | { | |
1d252fb8 | 1897 | char *msp; |
e114e473 CS |
1898 | int may; |
1899 | ||
1900 | switch (cmd) { | |
1901 | case IPC_STAT: | |
1902 | case MSG_STAT: | |
1903 | may = MAY_READ; | |
1904 | break; | |
1905 | case IPC_SET: | |
1906 | case IPC_RMID: | |
1907 | may = MAY_READWRITE; | |
1908 | break; | |
1909 | case IPC_INFO: | |
1910 | case MSG_INFO: | |
1911 | /* | |
1912 | * System level information | |
1913 | */ | |
1914 | return 0; | |
1915 | default: | |
1916 | return -EINVAL; | |
1917 | } | |
1918 | ||
1d252fb8 | 1919 | msp = smack_of_msq(msq); |
e114e473 CS |
1920 | return smk_curacc(msp, may); |
1921 | } | |
1922 | ||
1923 | /** | |
1924 | * smack_msg_queue_msgsnd - Smack access check for msg_queue | |
1925 | * @msq: the object | |
1926 | * @msg: unused | |
1927 | * @msqflg: access requested | |
1928 | * | |
1929 | * Returns 0 if current has the requested access, error code otherwise | |
1930 | */ | |
1931 | static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, | |
1932 | int msqflg) | |
1933 | { | |
1934 | char *msp = smack_of_msq(msq); | |
1935 | int rc; | |
1936 | ||
1937 | rc = smack_flags_to_may(msqflg); | |
1938 | return smk_curacc(msp, rc); | |
1939 | } | |
1940 | ||
1941 | /** | |
1942 | * smack_msg_queue_msgsnd - Smack access check for msg_queue | |
1943 | * @msq: the object | |
1944 | * @msg: unused | |
1945 | * @target: unused | |
1946 | * @type: unused | |
1947 | * @mode: unused | |
1948 | * | |
1949 | * Returns 0 if current has read and write access, error code otherwise | |
1950 | */ | |
1951 | static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, | |
1952 | struct task_struct *target, long type, int mode) | |
1953 | { | |
1954 | char *msp = smack_of_msq(msq); | |
1955 | ||
1956 | return smk_curacc(msp, MAY_READWRITE); | |
1957 | } | |
1958 | ||
1959 | /** | |
1960 | * smack_ipc_permission - Smack access for ipc_permission() | |
1961 | * @ipp: the object permissions | |
1962 | * @flag: access requested | |
1963 | * | |
1964 | * Returns 0 if current has read and write access, error code otherwise | |
1965 | */ | |
1966 | static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) | |
1967 | { | |
1968 | char *isp = ipp->security; | |
1969 | int may; | |
1970 | ||
1971 | may = smack_flags_to_may(flag); | |
1972 | return smk_curacc(isp, may); | |
1973 | } | |
1974 | ||
d20bdda6 AD |
1975 | /** |
1976 | * smack_ipc_getsecid - Extract smack security id | |
251a2a95 | 1977 | * @ipp: the object permissions |
d20bdda6 AD |
1978 | * @secid: where result will be saved |
1979 | */ | |
1980 | static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) | |
1981 | { | |
1982 | char *smack = ipp->security; | |
1983 | ||
1984 | *secid = smack_to_secid(smack); | |
1985 | } | |
1986 | ||
e114e473 CS |
1987 | /** |
1988 | * smack_d_instantiate - Make sure the blob is correct on an inode | |
1989 | * @opt_dentry: unused | |
1990 | * @inode: the object | |
1991 | * | |
1992 | * Set the inode's security blob if it hasn't been done already. | |
1993 | */ | |
1994 | static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) | |
1995 | { | |
1996 | struct super_block *sbp; | |
1997 | struct superblock_smack *sbsp; | |
1998 | struct inode_smack *isp; | |
86a264ab | 1999 | char *csp = current_security(); |
e114e473 CS |
2000 | char *fetched; |
2001 | char *final; | |
2002 | struct dentry *dp; | |
2003 | ||
2004 | if (inode == NULL) | |
2005 | return; | |
2006 | ||
2007 | isp = inode->i_security; | |
2008 | ||
2009 | mutex_lock(&isp->smk_lock); | |
2010 | /* | |
2011 | * If the inode is already instantiated | |
2012 | * take the quick way out | |
2013 | */ | |
2014 | if (isp->smk_flags & SMK_INODE_INSTANT) | |
2015 | goto unlockandout; | |
2016 | ||
2017 | sbp = inode->i_sb; | |
2018 | sbsp = sbp->s_security; | |
2019 | /* | |
2020 | * We're going to use the superblock default label | |
2021 | * if there's no label on the file. | |
2022 | */ | |
2023 | final = sbsp->smk_default; | |
2024 | ||
e97dcb0e CS |
2025 | /* |
2026 | * If this is the root inode the superblock | |
2027 | * may be in the process of initialization. | |
2028 | * If that is the case use the root value out | |
2029 | * of the superblock. | |
2030 | */ | |
2031 | if (opt_dentry->d_parent == opt_dentry) { | |
2032 | isp->smk_inode = sbsp->smk_root; | |
2033 | isp->smk_flags |= SMK_INODE_INSTANT; | |
2034 | goto unlockandout; | |
2035 | } | |
2036 | ||
e114e473 CS |
2037 | /* |
2038 | * This is pretty hackish. | |
2039 | * Casey says that we shouldn't have to do | |
2040 | * file system specific code, but it does help | |
2041 | * with keeping it simple. | |
2042 | */ | |
2043 | switch (sbp->s_magic) { | |
2044 | case SMACK_MAGIC: | |
2045 | /* | |
2046 | * Casey says that it's a little embarassing | |
2047 | * that the smack file system doesn't do | |
2048 | * extended attributes. | |
2049 | */ | |
2050 | final = smack_known_star.smk_known; | |
2051 | break; | |
2052 | case PIPEFS_MAGIC: | |
2053 | /* | |
2054 | * Casey says pipes are easy (?) | |
2055 | */ | |
2056 | final = smack_known_star.smk_known; | |
2057 | break; | |
2058 | case DEVPTS_SUPER_MAGIC: | |
2059 | /* | |
2060 | * devpts seems content with the label of the task. | |
2061 | * Programs that change smack have to treat the | |
2062 | * pty with respect. | |
2063 | */ | |
2064 | final = csp; | |
2065 | break; | |
2066 | case SOCKFS_MAGIC: | |
2067 | /* | |
2068 | * Casey says sockets get the smack of the task. | |
2069 | */ | |
2070 | final = csp; | |
2071 | break; | |
2072 | case PROC_SUPER_MAGIC: | |
2073 | /* | |
2074 | * Casey says procfs appears not to care. | |
2075 | * The superblock default suffices. | |
2076 | */ | |
2077 | break; | |
2078 | case TMPFS_MAGIC: | |
2079 | /* | |
2080 | * Device labels should come from the filesystem, | |
2081 | * but watch out, because they're volitile, | |
2082 | * getting recreated on every reboot. | |
2083 | */ | |
2084 | final = smack_known_star.smk_known; | |
2085 | /* | |
2086 | * No break. | |
2087 | * | |
2088 | * If a smack value has been set we want to use it, | |
2089 | * but since tmpfs isn't giving us the opportunity | |
2090 | * to set mount options simulate setting the | |
2091 | * superblock default. | |
2092 | */ | |
2093 | default: | |
2094 | /* | |
2095 | * This isn't an understood special case. | |
2096 | * Get the value from the xattr. | |
2097 | * | |
2098 | * No xattr support means, alas, no SMACK label. | |
2099 | * Use the aforeapplied default. | |
2100 | * It would be curious if the label of the task | |
2101 | * does not match that assigned. | |
2102 | */ | |
2103 | if (inode->i_op->getxattr == NULL) | |
2104 | break; | |
2105 | /* | |
2106 | * Get the dentry for xattr. | |
2107 | */ | |
2108 | if (opt_dentry == NULL) { | |
2109 | dp = d_find_alias(inode); | |
2110 | if (dp == NULL) | |
2111 | break; | |
2112 | } else { | |
2113 | dp = dget(opt_dentry); | |
2114 | if (dp == NULL) | |
2115 | break; | |
2116 | } | |
2117 | ||
2118 | fetched = smk_fetch(inode, dp); | |
2119 | if (fetched != NULL) | |
2120 | final = fetched; | |
2121 | ||
2122 | dput(dp); | |
2123 | break; | |
2124 | } | |
2125 | ||
2126 | if (final == NULL) | |
2127 | isp->smk_inode = csp; | |
2128 | else | |
2129 | isp->smk_inode = final; | |
2130 | ||
2131 | isp->smk_flags |= SMK_INODE_INSTANT; | |
2132 | ||
2133 | unlockandout: | |
2134 | mutex_unlock(&isp->smk_lock); | |
2135 | return; | |
2136 | } | |
2137 | ||
2138 | /** | |
2139 | * smack_getprocattr - Smack process attribute access | |
2140 | * @p: the object task | |
2141 | * @name: the name of the attribute in /proc/.../attr | |
2142 | * @value: where to put the result | |
2143 | * | |
2144 | * Places a copy of the task Smack into value | |
2145 | * | |
2146 | * Returns the length of the smack label or an error code | |
2147 | */ | |
2148 | static int smack_getprocattr(struct task_struct *p, char *name, char **value) | |
2149 | { | |
2150 | char *cp; | |
2151 | int slen; | |
2152 | ||
2153 | if (strcmp(name, "current") != 0) | |
2154 | return -EINVAL; | |
2155 | ||
c69e8d9c | 2156 | cp = kstrdup(task_security(p), GFP_KERNEL); |
e114e473 CS |
2157 | if (cp == NULL) |
2158 | return -ENOMEM; | |
2159 | ||
2160 | slen = strlen(cp); | |
2161 | *value = cp; | |
2162 | return slen; | |
2163 | } | |
2164 | ||
2165 | /** | |
2166 | * smack_setprocattr - Smack process attribute setting | |
2167 | * @p: the object task | |
2168 | * @name: the name of the attribute in /proc/.../attr | |
2169 | * @value: the value to set | |
2170 | * @size: the size of the value | |
2171 | * | |
2172 | * Sets the Smack value of the task. Only setting self | |
2173 | * is permitted and only with privilege | |
2174 | * | |
2175 | * Returns the length of the smack label or an error code | |
2176 | */ | |
2177 | static int smack_setprocattr(struct task_struct *p, char *name, | |
2178 | void *value, size_t size) | |
2179 | { | |
d84f4f99 | 2180 | struct cred *new; |
e114e473 CS |
2181 | char *newsmack; |
2182 | ||
e114e473 CS |
2183 | /* |
2184 | * Changing another process' Smack value is too dangerous | |
2185 | * and supports no sane use case. | |
2186 | */ | |
2187 | if (p != current) | |
2188 | return -EPERM; | |
2189 | ||
5cd9c58f DH |
2190 | if (!capable(CAP_MAC_ADMIN)) |
2191 | return -EPERM; | |
2192 | ||
e114e473 CS |
2193 | if (value == NULL || size == 0 || size >= SMK_LABELLEN) |
2194 | return -EINVAL; | |
2195 | ||
2196 | if (strcmp(name, "current") != 0) | |
2197 | return -EINVAL; | |
2198 | ||
2199 | newsmack = smk_import(value, size); | |
2200 | if (newsmack == NULL) | |
2201 | return -EINVAL; | |
2202 | ||
6d3dc07c CS |
2203 | /* |
2204 | * No process is ever allowed the web ("@") label. | |
2205 | */ | |
2206 | if (newsmack == smack_known_web.smk_known) | |
2207 | return -EPERM; | |
2208 | ||
d84f4f99 | 2209 | new = prepare_creds(); |
6d3dc07c | 2210 | if (new == NULL) |
d84f4f99 DH |
2211 | return -ENOMEM; |
2212 | new->security = newsmack; | |
2213 | commit_creds(new); | |
e114e473 CS |
2214 | return size; |
2215 | } | |
2216 | ||
2217 | /** | |
2218 | * smack_unix_stream_connect - Smack access on UDS | |
2219 | * @sock: one socket | |
2220 | * @other: the other socket | |
2221 | * @newsk: unused | |
2222 | * | |
2223 | * Return 0 if a subject with the smack of sock could access | |
2224 | * an object with the smack of other, otherwise an error code | |
2225 | */ | |
2226 | static int smack_unix_stream_connect(struct socket *sock, | |
2227 | struct socket *other, struct sock *newsk) | |
2228 | { | |
2229 | struct inode *sp = SOCK_INODE(sock); | |
2230 | struct inode *op = SOCK_INODE(other); | |
2231 | ||
2232 | return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE); | |
2233 | } | |
2234 | ||
2235 | /** | |
2236 | * smack_unix_may_send - Smack access on UDS | |
2237 | * @sock: one socket | |
2238 | * @other: the other socket | |
2239 | * | |
2240 | * Return 0 if a subject with the smack of sock could access | |
2241 | * an object with the smack of other, otherwise an error code | |
2242 | */ | |
2243 | static int smack_unix_may_send(struct socket *sock, struct socket *other) | |
2244 | { | |
2245 | struct inode *sp = SOCK_INODE(sock); | |
2246 | struct inode *op = SOCK_INODE(other); | |
2247 | ||
2248 | return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE); | |
2249 | } | |
2250 | ||
6d3dc07c CS |
2251 | /** |
2252 | * smack_socket_sendmsg - Smack check based on destination host | |
2253 | * @sock: the socket | |
251a2a95 | 2254 | * @msg: the message |
6d3dc07c CS |
2255 | * @size: the size of the message |
2256 | * | |
2257 | * Return 0 if the current subject can write to the destination | |
2258 | * host. This is only a question if the destination is a single | |
2259 | * label host. | |
2260 | */ | |
2261 | static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, | |
2262 | int size) | |
2263 | { | |
2264 | struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; | |
2265 | struct socket_smack *ssp = sock->sk->sk_security; | |
2266 | char *hostsp; | |
2267 | int rc; | |
2268 | ||
2269 | /* | |
2270 | * Perfectly reasonable for this to be NULL | |
2271 | */ | |
2272 | if (sip == NULL || sip->sin_family != PF_INET) | |
2273 | return 0; | |
2274 | ||
2275 | hostsp = smack_host_label(sip); | |
2276 | if (hostsp == NULL) { | |
2277 | if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) | |
2278 | return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); | |
2279 | return 0; | |
2280 | } | |
2281 | ||
2282 | rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); | |
2283 | if (rc != 0) | |
2284 | return rc; | |
2285 | ||
2286 | if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) | |
2287 | return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); | |
2288 | ||
2289 | return 0; | |
2290 | ||
2291 | } | |
2292 | ||
2293 | ||
e114e473 | 2294 | /** |
251a2a95 | 2295 | * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack |
e114e473 CS |
2296 | * @sap: netlabel secattr |
2297 | * @sip: where to put the result | |
2298 | * | |
2299 | * Copies a smack label into sip | |
2300 | */ | |
2301 | static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip) | |
2302 | { | |
2303 | char smack[SMK_LABELLEN]; | |
6d3dc07c | 2304 | char *sp; |
e114e473 CS |
2305 | int pcat; |
2306 | ||
6d3dc07c | 2307 | if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { |
e114e473 | 2308 | /* |
6d3dc07c | 2309 | * Looks like a CIPSO packet. |
e114e473 CS |
2310 | * If there are flags but no level netlabel isn't |
2311 | * behaving the way we expect it to. | |
2312 | * | |
6d3dc07c | 2313 | * Get the categories, if any |
e114e473 CS |
2314 | * Without guidance regarding the smack value |
2315 | * for the packet fall back on the network | |
2316 | * ambient value. | |
2317 | */ | |
6d3dc07c CS |
2318 | memset(smack, '\0', SMK_LABELLEN); |
2319 | if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0) | |
2320 | for (pcat = -1;;) { | |
2321 | pcat = netlbl_secattr_catmap_walk( | |
2322 | sap->attr.mls.cat, pcat + 1); | |
2323 | if (pcat < 0) | |
2324 | break; | |
2325 | smack_catset_bit(pcat, smack); | |
2326 | } | |
2327 | /* | |
2328 | * If it is CIPSO using smack direct mapping | |
2329 | * we are already done. WeeHee. | |
2330 | */ | |
2331 | if (sap->attr.mls.lvl == smack_cipso_direct) { | |
2332 | memcpy(sip, smack, SMK_MAXLEN); | |
2333 | return; | |
2334 | } | |
2335 | /* | |
2336 | * Look it up in the supplied table if it is not | |
2337 | * a direct mapping. | |
2338 | */ | |
2339 | smack_from_cipso(sap->attr.mls.lvl, smack, sip); | |
e114e473 CS |
2340 | return; |
2341 | } | |
6d3dc07c CS |
2342 | if ((sap->flags & NETLBL_SECATTR_SECID) != 0) { |
2343 | /* | |
2344 | * Looks like a fallback, which gives us a secid. | |
2345 | */ | |
2346 | sp = smack_from_secid(sap->attr.secid); | |
2347 | /* | |
2348 | * This has got to be a bug because it is | |
2349 | * impossible to specify a fallback without | |
2350 | * specifying the label, which will ensure | |
2351 | * it has a secid, and the only way to get a | |
2352 | * secid is from a fallback. | |
2353 | */ | |
2354 | BUG_ON(sp == NULL); | |
2355 | strncpy(sip, sp, SMK_MAXLEN); | |
e114e473 CS |
2356 | return; |
2357 | } | |
2358 | /* | |
6d3dc07c CS |
2359 | * Without guidance regarding the smack value |
2360 | * for the packet fall back on the network | |
2361 | * ambient value. | |
e114e473 | 2362 | */ |
6d3dc07c | 2363 | strncpy(sip, smack_net_ambient, SMK_MAXLEN); |
e114e473 CS |
2364 | return; |
2365 | } | |
2366 | ||
2367 | /** | |
2368 | * smack_socket_sock_rcv_skb - Smack packet delivery access check | |
2369 | * @sk: socket | |
2370 | * @skb: packet | |
2371 | * | |
2372 | * Returns 0 if the packet should be delivered, an error code otherwise | |
2373 | */ | |
2374 | static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) | |
2375 | { | |
2376 | struct netlbl_lsm_secattr secattr; | |
2377 | struct socket_smack *ssp = sk->sk_security; | |
2378 | char smack[SMK_LABELLEN]; | |
6d3dc07c | 2379 | char *csp; |
e114e473 CS |
2380 | int rc; |
2381 | ||
2382 | if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) | |
2383 | return 0; | |
2384 | ||
2385 | /* | |
2386 | * Translate what netlabel gave us. | |
2387 | */ | |
e114e473 | 2388 | netlbl_secattr_init(&secattr); |
6d3dc07c | 2389 | |
e114e473 | 2390 | rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); |
6d3dc07c | 2391 | if (rc == 0) { |
e114e473 | 2392 | smack_from_secattr(&secattr, smack); |
6d3dc07c CS |
2393 | csp = smack; |
2394 | } else | |
2395 | csp = smack_net_ambient; | |
2396 | ||
e114e473 | 2397 | netlbl_secattr_destroy(&secattr); |
6d3dc07c | 2398 | |
e114e473 CS |
2399 | /* |
2400 | * Receiving a packet requires that the other end | |
2401 | * be able to write here. Read access is not required. | |
2402 | * This is the simplist possible security model | |
2403 | * for networking. | |
2404 | */ | |
6d3dc07c | 2405 | rc = smk_access(csp, ssp->smk_in, MAY_WRITE); |
a8134296 PM |
2406 | if (rc != 0) |
2407 | netlbl_skbuff_err(skb, rc, 0); | |
2408 | return rc; | |
e114e473 CS |
2409 | } |
2410 | ||
2411 | /** | |
2412 | * smack_socket_getpeersec_stream - pull in packet label | |
2413 | * @sock: the socket | |
2414 | * @optval: user's destination | |
2415 | * @optlen: size thereof | |
251a2a95 | 2416 | * @len: max thereof |
e114e473 CS |
2417 | * |
2418 | * returns zero on success, an error code otherwise | |
2419 | */ | |
2420 | static int smack_socket_getpeersec_stream(struct socket *sock, | |
2421 | char __user *optval, | |
2422 | int __user *optlen, unsigned len) | |
2423 | { | |
2424 | struct socket_smack *ssp; | |
2425 | int slen; | |
2426 | int rc = 0; | |
2427 | ||
2428 | ssp = sock->sk->sk_security; | |
2429 | slen = strlen(ssp->smk_packet) + 1; | |
2430 | ||
2431 | if (slen > len) | |
2432 | rc = -ERANGE; | |
2433 | else if (copy_to_user(optval, ssp->smk_packet, slen) != 0) | |
2434 | rc = -EFAULT; | |
2435 | ||
2436 | if (put_user(slen, optlen) != 0) | |
2437 | rc = -EFAULT; | |
2438 | ||
2439 | return rc; | |
2440 | } | |
2441 | ||
2442 | ||
2443 | /** | |
2444 | * smack_socket_getpeersec_dgram - pull in packet label | |
2445 | * @sock: the socket | |
2446 | * @skb: packet data | |
2447 | * @secid: pointer to where to put the secid of the packet | |
2448 | * | |
2449 | * Sets the netlabel socket state on sk from parent | |
2450 | */ | |
2451 | static int smack_socket_getpeersec_dgram(struct socket *sock, | |
2452 | struct sk_buff *skb, u32 *secid) | |
2453 | ||
2454 | { | |
2455 | struct netlbl_lsm_secattr secattr; | |
2456 | struct sock *sk; | |
2457 | char smack[SMK_LABELLEN]; | |
2458 | int family = PF_INET; | |
2459 | u32 s; | |
2460 | int rc; | |
2461 | ||
2462 | /* | |
2463 | * Only works for families with packets. | |
2464 | */ | |
2465 | if (sock != NULL) { | |
2466 | sk = sock->sk; | |
2467 | if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) | |
2468 | return 0; | |
2469 | family = sk->sk_family; | |
2470 | } | |
2471 | /* | |
2472 | * Translate what netlabel gave us. | |
2473 | */ | |
e114e473 CS |
2474 | netlbl_secattr_init(&secattr); |
2475 | rc = netlbl_skbuff_getattr(skb, family, &secattr); | |
2476 | if (rc == 0) | |
2477 | smack_from_secattr(&secattr, smack); | |
2478 | netlbl_secattr_destroy(&secattr); | |
2479 | ||
2480 | /* | |
2481 | * Give up if we couldn't get anything | |
2482 | */ | |
2483 | if (rc != 0) | |
2484 | return rc; | |
2485 | ||
2486 | s = smack_to_secid(smack); | |
2487 | if (s == 0) | |
2488 | return -EINVAL; | |
2489 | ||
2490 | *secid = s; | |
2491 | return 0; | |
2492 | } | |
2493 | ||
2494 | /** | |
2495 | * smack_sock_graft - graft access state between two sockets | |
2496 | * @sk: fresh sock | |
2497 | * @parent: donor socket | |
2498 | * | |
2499 | * Sets the netlabel socket state on sk from parent | |
2500 | */ | |
2501 | static void smack_sock_graft(struct sock *sk, struct socket *parent) | |
2502 | { | |
2503 | struct socket_smack *ssp; | |
2504 | int rc; | |
2505 | ||
2506 | if (sk == NULL) | |
2507 | return; | |
2508 | ||
2509 | if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) | |
2510 | return; | |
2511 | ||
2512 | ssp = sk->sk_security; | |
86a264ab | 2513 | ssp->smk_in = ssp->smk_out = current_security(); |
e114e473 CS |
2514 | ssp->smk_packet[0] = '\0'; |
2515 | ||
6d3dc07c | 2516 | rc = smack_netlabel(sk, SMACK_CIPSO_SOCKET); |
4bc87e62 CS |
2517 | if (rc != 0) |
2518 | printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", | |
2519 | __func__, -rc); | |
e114e473 CS |
2520 | } |
2521 | ||
2522 | /** | |
2523 | * smack_inet_conn_request - Smack access check on connect | |
2524 | * @sk: socket involved | |
2525 | * @skb: packet | |
2526 | * @req: unused | |
2527 | * | |
2528 | * Returns 0 if a task with the packet label could write to | |
2529 | * the socket, otherwise an error code | |
2530 | */ | |
2531 | static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, | |
2532 | struct request_sock *req) | |
2533 | { | |
2534 | struct netlbl_lsm_secattr skb_secattr; | |
2535 | struct socket_smack *ssp = sk->sk_security; | |
2536 | char smack[SMK_LABELLEN]; | |
2537 | int rc; | |
2538 | ||
2539 | if (skb == NULL) | |
2540 | return -EACCES; | |
2541 | ||
e114e473 CS |
2542 | netlbl_secattr_init(&skb_secattr); |
2543 | rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr); | |
2544 | if (rc == 0) | |
2545 | smack_from_secattr(&skb_secattr, smack); | |
2546 | else | |
2547 | strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); | |
2548 | netlbl_secattr_destroy(&skb_secattr); | |
2549 | /* | |
2550 | * Receiving a packet requires that the other end | |
2551 | * be able to write here. Read access is not required. | |
2552 | * | |
2553 | * If the request is successful save the peer's label | |
2554 | * so that SO_PEERCRED can report it. | |
2555 | */ | |
2556 | rc = smk_access(smack, ssp->smk_in, MAY_WRITE); | |
2557 | if (rc == 0) | |
2558 | strncpy(ssp->smk_packet, smack, SMK_MAXLEN); | |
2559 | ||
2560 | return rc; | |
2561 | } | |
2562 | ||
2563 | /* | |
2564 | * Key management security hooks | |
2565 | * | |
2566 | * Casey has not tested key support very heavily. | |
2567 | * The permission check is most likely too restrictive. | |
2568 | * If you care about keys please have a look. | |
2569 | */ | |
2570 | #ifdef CONFIG_KEYS | |
2571 | ||
2572 | /** | |
2573 | * smack_key_alloc - Set the key security blob | |
2574 | * @key: object | |
d84f4f99 | 2575 | * @cred: the credentials to use |
e114e473 CS |
2576 | * @flags: unused |
2577 | * | |
2578 | * No allocation required | |
2579 | * | |
2580 | * Returns 0 | |
2581 | */ | |
d84f4f99 | 2582 | static int smack_key_alloc(struct key *key, const struct cred *cred, |
e114e473 CS |
2583 | unsigned long flags) |
2584 | { | |
d84f4f99 | 2585 | key->security = cred->security; |
e114e473 CS |
2586 | return 0; |
2587 | } | |
2588 | ||
2589 | /** | |
2590 | * smack_key_free - Clear the key security blob | |
2591 | * @key: the object | |
2592 | * | |
2593 | * Clear the blob pointer | |
2594 | */ | |
2595 | static void smack_key_free(struct key *key) | |
2596 | { | |
2597 | key->security = NULL; | |
2598 | } | |
2599 | ||
2600 | /* | |
2601 | * smack_key_permission - Smack access on a key | |
2602 | * @key_ref: gets to the object | |
d84f4f99 | 2603 | * @cred: the credentials to use |
e114e473 CS |
2604 | * @perm: unused |
2605 | * | |
2606 | * Return 0 if the task has read and write to the object, | |
2607 | * an error code otherwise | |
2608 | */ | |
2609 | static int smack_key_permission(key_ref_t key_ref, | |
d84f4f99 | 2610 | const struct cred *cred, key_perm_t perm) |
e114e473 CS |
2611 | { |
2612 | struct key *keyp; | |
2613 | ||
2614 | keyp = key_ref_to_ptr(key_ref); | |
2615 | if (keyp == NULL) | |
2616 | return -EINVAL; | |
2617 | /* | |
2618 | * If the key hasn't been initialized give it access so that | |
2619 | * it may do so. | |
2620 | */ | |
2621 | if (keyp->security == NULL) | |
2622 | return 0; | |
2623 | /* | |
2624 | * This should not occur | |
2625 | */ | |
d84f4f99 | 2626 | if (cred->security == NULL) |
e114e473 CS |
2627 | return -EACCES; |
2628 | ||
d84f4f99 | 2629 | return smk_access(cred->security, keyp->security, MAY_READWRITE); |
e114e473 CS |
2630 | } |
2631 | #endif /* CONFIG_KEYS */ | |
2632 | ||
d20bdda6 AD |
2633 | /* |
2634 | * Smack Audit hooks | |
2635 | * | |
2636 | * Audit requires a unique representation of each Smack specific | |
2637 | * rule. This unique representation is used to distinguish the | |
2638 | * object to be audited from remaining kernel objects and also | |
2639 | * works as a glue between the audit hooks. | |
2640 | * | |
2641 | * Since repository entries are added but never deleted, we'll use | |
2642 | * the smack_known label address related to the given audit rule as | |
2643 | * the needed unique representation. This also better fits the smack | |
2644 | * model where nearly everything is a label. | |
2645 | */ | |
2646 | #ifdef CONFIG_AUDIT | |
2647 | ||
2648 | /** | |
2649 | * smack_audit_rule_init - Initialize a smack audit rule | |
2650 | * @field: audit rule fields given from user-space (audit.h) | |
2651 | * @op: required testing operator (=, !=, >, <, ...) | |
2652 | * @rulestr: smack label to be audited | |
2653 | * @vrule: pointer to save our own audit rule representation | |
2654 | * | |
2655 | * Prepare to audit cases where (@field @op @rulestr) is true. | |
2656 | * The label to be audited is created if necessay. | |
2657 | */ | |
2658 | static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) | |
2659 | { | |
2660 | char **rule = (char **)vrule; | |
2661 | *rule = NULL; | |
2662 | ||
2663 | if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) | |
2664 | return -EINVAL; | |
2665 | ||
5af75d8d | 2666 | if (op != Audit_equal && op != Audit_not_equal) |
d20bdda6 AD |
2667 | return -EINVAL; |
2668 | ||
2669 | *rule = smk_import(rulestr, 0); | |
2670 | ||
2671 | return 0; | |
2672 | } | |
2673 | ||
2674 | /** | |
2675 | * smack_audit_rule_known - Distinguish Smack audit rules | |
2676 | * @krule: rule of interest, in Audit kernel representation format | |
2677 | * | |
2678 | * This is used to filter Smack rules from remaining Audit ones. | |
2679 | * If it's proved that this rule belongs to us, the | |
2680 | * audit_rule_match hook will be called to do the final judgement. | |
2681 | */ | |
2682 | static int smack_audit_rule_known(struct audit_krule *krule) | |
2683 | { | |
2684 | struct audit_field *f; | |
2685 | int i; | |
2686 | ||
2687 | for (i = 0; i < krule->field_count; i++) { | |
2688 | f = &krule->fields[i]; | |
2689 | ||
2690 | if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER) | |
2691 | return 1; | |
2692 | } | |
2693 | ||
2694 | return 0; | |
2695 | } | |
2696 | ||
2697 | /** | |
2698 | * smack_audit_rule_match - Audit given object ? | |
2699 | * @secid: security id for identifying the object to test | |
2700 | * @field: audit rule flags given from user-space | |
2701 | * @op: required testing operator | |
2702 | * @vrule: smack internal rule presentation | |
2703 | * @actx: audit context associated with the check | |
2704 | * | |
2705 | * The core Audit hook. It's used to take the decision of | |
2706 | * whether to audit or not to audit a given object. | |
2707 | */ | |
2708 | static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule, | |
2709 | struct audit_context *actx) | |
2710 | { | |
2711 | char *smack; | |
2712 | char *rule = vrule; | |
2713 | ||
2714 | if (!rule) { | |
2715 | audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR, | |
2716 | "Smack: missing rule\n"); | |
2717 | return -ENOENT; | |
2718 | } | |
2719 | ||
2720 | if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) | |
2721 | return 0; | |
2722 | ||
2723 | smack = smack_from_secid(secid); | |
2724 | ||
2725 | /* | |
2726 | * No need to do string comparisons. If a match occurs, | |
2727 | * both pointers will point to the same smack_known | |
2728 | * label. | |
2729 | */ | |
5af75d8d | 2730 | if (op == Audit_equal) |
d20bdda6 | 2731 | return (rule == smack); |
5af75d8d | 2732 | if (op == Audit_not_equal) |
d20bdda6 AD |
2733 | return (rule != smack); |
2734 | ||
2735 | return 0; | |
2736 | } | |
2737 | ||
2738 | /** | |
2739 | * smack_audit_rule_free - free smack rule representation | |
2740 | * @vrule: rule to be freed. | |
2741 | * | |
2742 | * No memory was allocated. | |
2743 | */ | |
2744 | static void smack_audit_rule_free(void *vrule) | |
2745 | { | |
2746 | /* No-op */ | |
2747 | } | |
2748 | ||
2749 | #endif /* CONFIG_AUDIT */ | |
2750 | ||
251a2a95 | 2751 | /** |
e114e473 CS |
2752 | * smack_secid_to_secctx - return the smack label for a secid |
2753 | * @secid: incoming integer | |
2754 | * @secdata: destination | |
2755 | * @seclen: how long it is | |
2756 | * | |
2757 | * Exists for networking code. | |
2758 | */ | |
2759 | static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) | |
2760 | { | |
2761 | char *sp = smack_from_secid(secid); | |
2762 | ||
2763 | *secdata = sp; | |
2764 | *seclen = strlen(sp); | |
2765 | return 0; | |
2766 | } | |
2767 | ||
251a2a95 | 2768 | /** |
4bc87e62 CS |
2769 | * smack_secctx_to_secid - return the secid for a smack label |
2770 | * @secdata: smack label | |
2771 | * @seclen: how long result is | |
2772 | * @secid: outgoing integer | |
2773 | * | |
2774 | * Exists for audit and networking code. | |
2775 | */ | |
e52c1764 | 2776 | static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
4bc87e62 CS |
2777 | { |
2778 | *secid = smack_to_secid(secdata); | |
2779 | return 0; | |
2780 | } | |
2781 | ||
251a2a95 | 2782 | /** |
e114e473 | 2783 | * smack_release_secctx - don't do anything. |
251a2a95 RD |
2784 | * @secdata: unused |
2785 | * @seclen: unused | |
e114e473 CS |
2786 | * |
2787 | * Exists to make sure nothing gets done, and properly | |
2788 | */ | |
2789 | static void smack_release_secctx(char *secdata, u32 seclen) | |
2790 | { | |
2791 | } | |
2792 | ||
076c54c5 AD |
2793 | struct security_operations smack_ops = { |
2794 | .name = "smack", | |
2795 | ||
5cd9c58f DH |
2796 | .ptrace_may_access = smack_ptrace_may_access, |
2797 | .ptrace_traceme = smack_ptrace_traceme, | |
e114e473 | 2798 | .capget = cap_capget, |
d84f4f99 | 2799 | .capset = cap_capset, |
e114e473 CS |
2800 | .capable = cap_capable, |
2801 | .syslog = smack_syslog, | |
2802 | .settime = cap_settime, | |
2803 | .vm_enough_memory = cap_vm_enough_memory, | |
2804 | ||
a6f76f23 | 2805 | .bprm_set_creds = cap_bprm_set_creds, |
e114e473 CS |
2806 | .bprm_secureexec = cap_bprm_secureexec, |
2807 | ||
2808 | .sb_alloc_security = smack_sb_alloc_security, | |
2809 | .sb_free_security = smack_sb_free_security, | |
2810 | .sb_copy_data = smack_sb_copy_data, | |
2811 | .sb_kern_mount = smack_sb_kern_mount, | |
2812 | .sb_statfs = smack_sb_statfs, | |
2813 | .sb_mount = smack_sb_mount, | |
2814 | .sb_umount = smack_sb_umount, | |
2815 | ||
2816 | .inode_alloc_security = smack_inode_alloc_security, | |
2817 | .inode_free_security = smack_inode_free_security, | |
2818 | .inode_init_security = smack_inode_init_security, | |
2819 | .inode_link = smack_inode_link, | |
2820 | .inode_unlink = smack_inode_unlink, | |
2821 | .inode_rmdir = smack_inode_rmdir, | |
2822 | .inode_rename = smack_inode_rename, | |
2823 | .inode_permission = smack_inode_permission, | |
2824 | .inode_setattr = smack_inode_setattr, | |
2825 | .inode_getattr = smack_inode_getattr, | |
2826 | .inode_setxattr = smack_inode_setxattr, | |
2827 | .inode_post_setxattr = smack_inode_post_setxattr, | |
2828 | .inode_getxattr = smack_inode_getxattr, | |
2829 | .inode_removexattr = smack_inode_removexattr, | |
bcdca225 CS |
2830 | .inode_need_killpriv = cap_inode_need_killpriv, |
2831 | .inode_killpriv = cap_inode_killpriv, | |
e114e473 CS |
2832 | .inode_getsecurity = smack_inode_getsecurity, |
2833 | .inode_setsecurity = smack_inode_setsecurity, | |
2834 | .inode_listsecurity = smack_inode_listsecurity, | |
d20bdda6 | 2835 | .inode_getsecid = smack_inode_getsecid, |
e114e473 CS |
2836 | |
2837 | .file_permission = smack_file_permission, | |
2838 | .file_alloc_security = smack_file_alloc_security, | |
2839 | .file_free_security = smack_file_free_security, | |
2840 | .file_ioctl = smack_file_ioctl, | |
2841 | .file_lock = smack_file_lock, | |
2842 | .file_fcntl = smack_file_fcntl, | |
2843 | .file_set_fowner = smack_file_set_fowner, | |
2844 | .file_send_sigiotask = smack_file_send_sigiotask, | |
2845 | .file_receive = smack_file_receive, | |
2846 | ||
f1752eec | 2847 | .cred_free = smack_cred_free, |
d84f4f99 DH |
2848 | .cred_prepare = smack_cred_prepare, |
2849 | .cred_commit = smack_cred_commit, | |
3a3b7ce9 DH |
2850 | .kernel_act_as = smack_kernel_act_as, |
2851 | .kernel_create_files_as = smack_kernel_create_files_as, | |
d84f4f99 | 2852 | .task_fix_setuid = cap_task_fix_setuid, |
e114e473 CS |
2853 | .task_setpgid = smack_task_setpgid, |
2854 | .task_getpgid = smack_task_getpgid, | |
2855 | .task_getsid = smack_task_getsid, | |
2856 | .task_getsecid = smack_task_getsecid, | |
2857 | .task_setnice = smack_task_setnice, | |
2858 | .task_setioprio = smack_task_setioprio, | |
2859 | .task_getioprio = smack_task_getioprio, | |
2860 | .task_setscheduler = smack_task_setscheduler, | |
2861 | .task_getscheduler = smack_task_getscheduler, | |
2862 | .task_movememory = smack_task_movememory, | |
2863 | .task_kill = smack_task_kill, | |
2864 | .task_wait = smack_task_wait, | |
e114e473 | 2865 | .task_to_inode = smack_task_to_inode, |
1236cc3c | 2866 | .task_prctl = cap_task_prctl, |
e114e473 CS |
2867 | |
2868 | .ipc_permission = smack_ipc_permission, | |
d20bdda6 | 2869 | .ipc_getsecid = smack_ipc_getsecid, |
e114e473 CS |
2870 | |
2871 | .msg_msg_alloc_security = smack_msg_msg_alloc_security, | |
2872 | .msg_msg_free_security = smack_msg_msg_free_security, | |
2873 | ||
2874 | .msg_queue_alloc_security = smack_msg_queue_alloc_security, | |
2875 | .msg_queue_free_security = smack_msg_queue_free_security, | |
2876 | .msg_queue_associate = smack_msg_queue_associate, | |
2877 | .msg_queue_msgctl = smack_msg_queue_msgctl, | |
2878 | .msg_queue_msgsnd = smack_msg_queue_msgsnd, | |
2879 | .msg_queue_msgrcv = smack_msg_queue_msgrcv, | |
2880 | ||
2881 | .shm_alloc_security = smack_shm_alloc_security, | |
2882 | .shm_free_security = smack_shm_free_security, | |
2883 | .shm_associate = smack_shm_associate, | |
2884 | .shm_shmctl = smack_shm_shmctl, | |
2885 | .shm_shmat = smack_shm_shmat, | |
2886 | ||
2887 | .sem_alloc_security = smack_sem_alloc_security, | |
2888 | .sem_free_security = smack_sem_free_security, | |
2889 | .sem_associate = smack_sem_associate, | |
2890 | .sem_semctl = smack_sem_semctl, | |
2891 | .sem_semop = smack_sem_semop, | |
2892 | ||
2893 | .netlink_send = cap_netlink_send, | |
2894 | .netlink_recv = cap_netlink_recv, | |
2895 | ||
2896 | .d_instantiate = smack_d_instantiate, | |
2897 | ||
2898 | .getprocattr = smack_getprocattr, | |
2899 | .setprocattr = smack_setprocattr, | |
2900 | ||
2901 | .unix_stream_connect = smack_unix_stream_connect, | |
2902 | .unix_may_send = smack_unix_may_send, | |
2903 | ||
2904 | .socket_post_create = smack_socket_post_create, | |
6d3dc07c CS |
2905 | .socket_connect = smack_socket_connect, |
2906 | .socket_sendmsg = smack_socket_sendmsg, | |
e114e473 CS |
2907 | .socket_sock_rcv_skb = smack_socket_sock_rcv_skb, |
2908 | .socket_getpeersec_stream = smack_socket_getpeersec_stream, | |
2909 | .socket_getpeersec_dgram = smack_socket_getpeersec_dgram, | |
2910 | .sk_alloc_security = smack_sk_alloc_security, | |
2911 | .sk_free_security = smack_sk_free_security, | |
2912 | .sock_graft = smack_sock_graft, | |
2913 | .inet_conn_request = smack_inet_conn_request, | |
d20bdda6 | 2914 | |
e114e473 CS |
2915 | /* key management security hooks */ |
2916 | #ifdef CONFIG_KEYS | |
2917 | .key_alloc = smack_key_alloc, | |
2918 | .key_free = smack_key_free, | |
2919 | .key_permission = smack_key_permission, | |
2920 | #endif /* CONFIG_KEYS */ | |
d20bdda6 AD |
2921 | |
2922 | /* Audit hooks */ | |
2923 | #ifdef CONFIG_AUDIT | |
2924 | .audit_rule_init = smack_audit_rule_init, | |
2925 | .audit_rule_known = smack_audit_rule_known, | |
2926 | .audit_rule_match = smack_audit_rule_match, | |
2927 | .audit_rule_free = smack_audit_rule_free, | |
2928 | #endif /* CONFIG_AUDIT */ | |
2929 | ||
e114e473 | 2930 | .secid_to_secctx = smack_secid_to_secctx, |
4bc87e62 | 2931 | .secctx_to_secid = smack_secctx_to_secid, |
e114e473 CS |
2932 | .release_secctx = smack_release_secctx, |
2933 | }; | |
2934 | ||
7198e2ee EB |
2935 | |
2936 | static __init void init_smack_know_list(void) | |
2937 | { | |
2938 | list_add(&smack_known_huh.list, &smack_known_list); | |
2939 | list_add(&smack_known_hat.list, &smack_known_list); | |
2940 | list_add(&smack_known_star.list, &smack_known_list); | |
2941 | list_add(&smack_known_floor.list, &smack_known_list); | |
2942 | list_add(&smack_known_invalid.list, &smack_known_list); | |
2943 | list_add(&smack_known_web.list, &smack_known_list); | |
2944 | } | |
2945 | ||
e114e473 CS |
2946 | /** |
2947 | * smack_init - initialize the smack system | |
2948 | * | |
2949 | * Returns 0 | |
2950 | */ | |
2951 | static __init int smack_init(void) | |
2952 | { | |
d84f4f99 DH |
2953 | struct cred *cred; |
2954 | ||
076c54c5 AD |
2955 | if (!security_module_enable(&smack_ops)) |
2956 | return 0; | |
2957 | ||
e114e473 CS |
2958 | printk(KERN_INFO "Smack: Initializing.\n"); |
2959 | ||
2960 | /* | |
2961 | * Set the security state for the initial task. | |
2962 | */ | |
d84f4f99 DH |
2963 | cred = (struct cred *) current->cred; |
2964 | cred->security = &smack_known_floor.smk_known; | |
e114e473 | 2965 | |
7198e2ee EB |
2966 | /* initilize the smack_know_list */ |
2967 | init_smack_know_list(); | |
e114e473 CS |
2968 | /* |
2969 | * Initialize locks | |
2970 | */ | |
e114e473 CS |
2971 | spin_lock_init(&smack_known_huh.smk_cipsolock); |
2972 | spin_lock_init(&smack_known_hat.smk_cipsolock); | |
2973 | spin_lock_init(&smack_known_star.smk_cipsolock); | |
2974 | spin_lock_init(&smack_known_floor.smk_cipsolock); | |
2975 | spin_lock_init(&smack_known_invalid.smk_cipsolock); | |
2976 | ||
2977 | /* | |
2978 | * Register with LSM | |
2979 | */ | |
2980 | if (register_security(&smack_ops)) | |
2981 | panic("smack: Unable to register with kernel.\n"); | |
2982 | ||
2983 | return 0; | |
2984 | } | |
2985 | ||
2986 | /* | |
2987 | * Smack requires early initialization in order to label | |
2988 | * all processes and objects when they are created. | |
2989 | */ | |
2990 | security_initcall(smack_init); |