xref: /openbmc/linux/security/apparmor/lsm.c (revision 92b19ff5)
1 /*
2  * AppArmor security module
3  *
4  * This file contains AppArmor LSM hooks.
5  *
6  * Copyright (C) 1998-2008 Novell/SUSE
7  * Copyright 2009-2010 Canonical Ltd.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation, version 2 of the
12  * License.
13  */
14 
15 #include <linux/lsm_hooks.h>
16 #include <linux/moduleparam.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/mount.h>
20 #include <linux/namei.h>
21 #include <linux/ptrace.h>
22 #include <linux/ctype.h>
23 #include <linux/sysctl.h>
24 #include <linux/audit.h>
25 #include <linux/user_namespace.h>
26 #include <net/sock.h>
27 
28 #include "include/apparmor.h"
29 #include "include/apparmorfs.h"
30 #include "include/audit.h"
31 #include "include/capability.h"
32 #include "include/context.h"
33 #include "include/file.h"
34 #include "include/ipc.h"
35 #include "include/path.h"
36 #include "include/policy.h"
37 #include "include/procattr.h"
38 
39 /* Flag indicating whether initialization completed */
40 int apparmor_initialized __initdata;
41 
42 /*
43  * LSM hook functions
44  */
45 
46 /*
47  * free the associated aa_task_cxt and put its profiles
48  */
49 static void apparmor_cred_free(struct cred *cred)
50 {
51 	aa_free_task_context(cred_cxt(cred));
52 	cred_cxt(cred) = NULL;
53 }
54 
55 /*
56  * allocate the apparmor part of blank credentials
57  */
58 static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
59 {
60 	/* freed by apparmor_cred_free */
61 	struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
62 	if (!cxt)
63 		return -ENOMEM;
64 
65 	cred_cxt(cred) = cxt;
66 	return 0;
67 }
68 
69 /*
70  * prepare new aa_task_cxt for modification by prepare_cred block
71  */
72 static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
73 				 gfp_t gfp)
74 {
75 	/* freed by apparmor_cred_free */
76 	struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
77 	if (!cxt)
78 		return -ENOMEM;
79 
80 	aa_dup_task_context(cxt, cred_cxt(old));
81 	cred_cxt(new) = cxt;
82 	return 0;
83 }
84 
85 /*
86  * transfer the apparmor data to a blank set of creds
87  */
88 static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
89 {
90 	const struct aa_task_cxt *old_cxt = cred_cxt(old);
91 	struct aa_task_cxt *new_cxt = cred_cxt(new);
92 
93 	aa_dup_task_context(new_cxt, old_cxt);
94 }
95 
96 static int apparmor_ptrace_access_check(struct task_struct *child,
97 					unsigned int mode)
98 {
99 	return aa_ptrace(current, child, mode);
100 }
101 
102 static int apparmor_ptrace_traceme(struct task_struct *parent)
103 {
104 	return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
105 }
106 
107 /* Derived from security/commoncap.c:cap_capget */
108 static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
109 			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
110 {
111 	struct aa_profile *profile;
112 	const struct cred *cred;
113 
114 	rcu_read_lock();
115 	cred = __task_cred(target);
116 	profile = aa_cred_profile(cred);
117 
118 	/*
119 	 * cap_capget is stacked ahead of this and will
120 	 * initialize effective and permitted.
121 	 */
122 	if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
123 		*effective = cap_intersect(*effective, profile->caps.allow);
124 		*permitted = cap_intersect(*permitted, profile->caps.allow);
125 	}
126 	rcu_read_unlock();
127 
128 	return 0;
129 }
130 
131 static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
132 			    int cap, int audit)
133 {
134 	struct aa_profile *profile;
135 	int error = 0;
136 
137 	profile = aa_cred_profile(cred);
138 	if (!unconfined(profile))
139 		error = aa_capable(profile, cap, audit);
140 	return error;
141 }
142 
143 /**
144  * common_perm - basic common permission check wrapper fn for paths
145  * @op: operation being checked
146  * @path: path to check permission of  (NOT NULL)
147  * @mask: requested permissions mask
148  * @cond: conditional info for the permission request  (NOT NULL)
149  *
150  * Returns: %0 else error code if error or permission denied
151  */
152 static int common_perm(int op, struct path *path, u32 mask,
153 		       struct path_cond *cond)
154 {
155 	struct aa_profile *profile;
156 	int error = 0;
157 
158 	profile = __aa_current_profile();
159 	if (!unconfined(profile))
160 		error = aa_path_perm(op, profile, path, 0, mask, cond);
161 
162 	return error;
163 }
164 
165 /**
166  * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
167  * @op: operation being checked
168  * @dir: directory of the dentry  (NOT NULL)
169  * @dentry: dentry to check  (NOT NULL)
170  * @mask: requested permissions mask
171  * @cond: conditional info for the permission request  (NOT NULL)
172  *
173  * Returns: %0 else error code if error or permission denied
174  */
175 static int common_perm_dir_dentry(int op, struct path *dir,
176 				  struct dentry *dentry, u32 mask,
177 				  struct path_cond *cond)
178 {
179 	struct path path = { dir->mnt, dentry };
180 
181 	return common_perm(op, &path, mask, cond);
182 }
183 
184 /**
185  * common_perm_mnt_dentry - common permission wrapper when mnt, dentry
186  * @op: operation being checked
187  * @mnt: mount point of dentry (NOT NULL)
188  * @dentry: dentry to check  (NOT NULL)
189  * @mask: requested permissions mask
190  *
191  * Returns: %0 else error code if error or permission denied
192  */
193 static int common_perm_mnt_dentry(int op, struct vfsmount *mnt,
194 				  struct dentry *dentry, u32 mask)
195 {
196 	struct path path = { mnt, dentry };
197 	struct path_cond cond = { d_backing_inode(dentry)->i_uid,
198 				  d_backing_inode(dentry)->i_mode
199 	};
200 
201 	return common_perm(op, &path, mask, &cond);
202 }
203 
204 /**
205  * common_perm_rm - common permission wrapper for operations doing rm
206  * @op: operation being checked
207  * @dir: directory that the dentry is in  (NOT NULL)
208  * @dentry: dentry being rm'd  (NOT NULL)
209  * @mask: requested permission mask
210  *
211  * Returns: %0 else error code if error or permission denied
212  */
213 static int common_perm_rm(int op, struct path *dir,
214 			  struct dentry *dentry, u32 mask)
215 {
216 	struct inode *inode = d_backing_inode(dentry);
217 	struct path_cond cond = { };
218 
219 	if (!inode || !dir->mnt || !mediated_filesystem(dentry))
220 		return 0;
221 
222 	cond.uid = inode->i_uid;
223 	cond.mode = inode->i_mode;
224 
225 	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
226 }
227 
228 /**
229  * common_perm_create - common permission wrapper for operations doing create
230  * @op: operation being checked
231  * @dir: directory that dentry will be created in  (NOT NULL)
232  * @dentry: dentry to create   (NOT NULL)
233  * @mask: request permission mask
234  * @mode: created file mode
235  *
236  * Returns: %0 else error code if error or permission denied
237  */
238 static int common_perm_create(int op, struct path *dir, struct dentry *dentry,
239 			      u32 mask, umode_t mode)
240 {
241 	struct path_cond cond = { current_fsuid(), mode };
242 
243 	if (!dir->mnt || !mediated_filesystem(dir->dentry))
244 		return 0;
245 
246 	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
247 }
248 
249 static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
250 {
251 	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
252 }
253 
254 static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
255 			       umode_t mode)
256 {
257 	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
258 				  S_IFDIR);
259 }
260 
261 static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
262 {
263 	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
264 }
265 
266 static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
267 			       umode_t mode, unsigned int dev)
268 {
269 	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
270 }
271 
272 static int apparmor_path_truncate(struct path *path)
273 {
274 	struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
275 				  d_backing_inode(path->dentry)->i_mode
276 	};
277 
278 	if (!path->mnt || !mediated_filesystem(path->dentry))
279 		return 0;
280 
281 	return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE,
282 			   &cond);
283 }
284 
285 static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
286 				 const char *old_name)
287 {
288 	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
289 				  S_IFLNK);
290 }
291 
292 static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir,
293 			      struct dentry *new_dentry)
294 {
295 	struct aa_profile *profile;
296 	int error = 0;
297 
298 	if (!mediated_filesystem(old_dentry))
299 		return 0;
300 
301 	profile = aa_current_profile();
302 	if (!unconfined(profile))
303 		error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
304 	return error;
305 }
306 
307 static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry,
308 				struct path *new_dir, struct dentry *new_dentry)
309 {
310 	struct aa_profile *profile;
311 	int error = 0;
312 
313 	if (!mediated_filesystem(old_dentry))
314 		return 0;
315 
316 	profile = aa_current_profile();
317 	if (!unconfined(profile)) {
318 		struct path old_path = { old_dir->mnt, old_dentry };
319 		struct path new_path = { new_dir->mnt, new_dentry };
320 		struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
321 					  d_backing_inode(old_dentry)->i_mode
322 		};
323 
324 		error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
325 				     MAY_READ | AA_MAY_META_READ | MAY_WRITE |
326 				     AA_MAY_META_WRITE | AA_MAY_DELETE,
327 				     &cond);
328 		if (!error)
329 			error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
330 					     0, MAY_WRITE | AA_MAY_META_WRITE |
331 					     AA_MAY_CREATE, &cond);
332 
333 	}
334 	return error;
335 }
336 
337 static int apparmor_path_chmod(struct path *path, umode_t mode)
338 {
339 	if (!mediated_filesystem(path->dentry))
340 		return 0;
341 
342 	return common_perm_mnt_dentry(OP_CHMOD, path->mnt, path->dentry, AA_MAY_CHMOD);
343 }
344 
345 static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid)
346 {
347 	struct path_cond cond =  { d_backing_inode(path->dentry)->i_uid,
348 				   d_backing_inode(path->dentry)->i_mode
349 	};
350 
351 	if (!mediated_filesystem(path->dentry))
352 		return 0;
353 
354 	return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
355 }
356 
357 static int apparmor_inode_getattr(const struct path *path)
358 {
359 	if (!mediated_filesystem(path->dentry))
360 		return 0;
361 
362 	return common_perm_mnt_dentry(OP_GETATTR, path->mnt, path->dentry,
363 				      AA_MAY_META_READ);
364 }
365 
366 static int apparmor_file_open(struct file *file, const struct cred *cred)
367 {
368 	struct aa_file_cxt *fcxt = file->f_security;
369 	struct aa_profile *profile;
370 	int error = 0;
371 
372 	if (!mediated_filesystem(file->f_path.dentry))
373 		return 0;
374 
375 	/* If in exec, permission is handled by bprm hooks.
376 	 * Cache permissions granted by the previous exec check, with
377 	 * implicit read and executable mmap which are required to
378 	 * actually execute the image.
379 	 */
380 	if (current->in_execve) {
381 		fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
382 		return 0;
383 	}
384 
385 	profile = aa_cred_profile(cred);
386 	if (!unconfined(profile)) {
387 		struct inode *inode = file_inode(file);
388 		struct path_cond cond = { inode->i_uid, inode->i_mode };
389 
390 		error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
391 				     aa_map_file_to_perms(file), &cond);
392 		/* todo cache full allowed permissions set and state */
393 		fcxt->allow = aa_map_file_to_perms(file);
394 	}
395 
396 	return error;
397 }
398 
399 static int apparmor_file_alloc_security(struct file *file)
400 {
401 	/* freed by apparmor_file_free_security */
402 	file->f_security = aa_alloc_file_context(GFP_KERNEL);
403 	if (!file->f_security)
404 		return -ENOMEM;
405 	return 0;
406 
407 }
408 
409 static void apparmor_file_free_security(struct file *file)
410 {
411 	struct aa_file_cxt *cxt = file->f_security;
412 
413 	aa_free_file_context(cxt);
414 }
415 
416 static int common_file_perm(int op, struct file *file, u32 mask)
417 {
418 	struct aa_file_cxt *fcxt = file->f_security;
419 	struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
420 	int error = 0;
421 
422 	BUG_ON(!fprofile);
423 
424 	if (!file->f_path.mnt ||
425 	    !mediated_filesystem(file->f_path.dentry))
426 		return 0;
427 
428 	profile = __aa_current_profile();
429 
430 	/* revalidate access, if task is unconfined, or the cached cred
431 	 * doesn't match or if the request is for more permissions than
432 	 * was granted.
433 	 *
434 	 * Note: the test for !unconfined(fprofile) is to handle file
435 	 *       delegation from unconfined tasks
436 	 */
437 	if (!unconfined(profile) && !unconfined(fprofile) &&
438 	    ((fprofile != profile) || (mask & ~fcxt->allow)))
439 		error = aa_file_perm(op, profile, file, mask);
440 
441 	return error;
442 }
443 
444 static int apparmor_file_permission(struct file *file, int mask)
445 {
446 	return common_file_perm(OP_FPERM, file, mask);
447 }
448 
449 static int apparmor_file_lock(struct file *file, unsigned int cmd)
450 {
451 	u32 mask = AA_MAY_LOCK;
452 
453 	if (cmd == F_WRLCK)
454 		mask |= MAY_WRITE;
455 
456 	return common_file_perm(OP_FLOCK, file, mask);
457 }
458 
459 static int common_mmap(int op, struct file *file, unsigned long prot,
460 		       unsigned long flags)
461 {
462 	int mask = 0;
463 
464 	if (!file || !file->f_security)
465 		return 0;
466 
467 	if (prot & PROT_READ)
468 		mask |= MAY_READ;
469 	/*
470 	 * Private mappings don't require write perms since they don't
471 	 * write back to the files
472 	 */
473 	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
474 		mask |= MAY_WRITE;
475 	if (prot & PROT_EXEC)
476 		mask |= AA_EXEC_MMAP;
477 
478 	return common_file_perm(op, file, mask);
479 }
480 
481 static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
482 			      unsigned long prot, unsigned long flags)
483 {
484 	return common_mmap(OP_FMMAP, file, prot, flags);
485 }
486 
487 static int apparmor_file_mprotect(struct vm_area_struct *vma,
488 				  unsigned long reqprot, unsigned long prot)
489 {
490 	return common_mmap(OP_FMPROT, vma->vm_file, prot,
491 			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
492 }
493 
494 static int apparmor_getprocattr(struct task_struct *task, char *name,
495 				char **value)
496 {
497 	int error = -ENOENT;
498 	/* released below */
499 	const struct cred *cred = get_task_cred(task);
500 	struct aa_task_cxt *cxt = cred_cxt(cred);
501 	struct aa_profile *profile = NULL;
502 
503 	if (strcmp(name, "current") == 0)
504 		profile = aa_get_newest_profile(cxt->profile);
505 	else if (strcmp(name, "prev") == 0  && cxt->previous)
506 		profile = aa_get_newest_profile(cxt->previous);
507 	else if (strcmp(name, "exec") == 0 && cxt->onexec)
508 		profile = aa_get_newest_profile(cxt->onexec);
509 	else
510 		error = -EINVAL;
511 
512 	if (profile)
513 		error = aa_getprocattr(profile, value);
514 
515 	aa_put_profile(profile);
516 	put_cred(cred);
517 
518 	return error;
519 }
520 
521 static int apparmor_setprocattr(struct task_struct *task, char *name,
522 				void *value, size_t size)
523 {
524 	struct common_audit_data sa;
525 	struct apparmor_audit_data aad = {0,};
526 	char *command, *args = value;
527 	size_t arg_size;
528 	int error;
529 
530 	if (size == 0)
531 		return -EINVAL;
532 	/* args points to a PAGE_SIZE buffer, AppArmor requires that
533 	 * the buffer must be null terminated or have size <= PAGE_SIZE -1
534 	 * so that AppArmor can null terminate them
535 	 */
536 	if (args[size - 1] != '\0') {
537 		if (size == PAGE_SIZE)
538 			return -EINVAL;
539 		args[size] = '\0';
540 	}
541 
542 	/* task can only write its own attributes */
543 	if (current != task)
544 		return -EACCES;
545 
546 	args = value;
547 	args = strim(args);
548 	command = strsep(&args, " ");
549 	if (!args)
550 		return -EINVAL;
551 	args = skip_spaces(args);
552 	if (!*args)
553 		return -EINVAL;
554 
555 	arg_size = size - (args - (char *) value);
556 	if (strcmp(name, "current") == 0) {
557 		if (strcmp(command, "changehat") == 0) {
558 			error = aa_setprocattr_changehat(args, arg_size,
559 							 !AA_DO_TEST);
560 		} else if (strcmp(command, "permhat") == 0) {
561 			error = aa_setprocattr_changehat(args, arg_size,
562 							 AA_DO_TEST);
563 		} else if (strcmp(command, "changeprofile") == 0) {
564 			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
565 							     !AA_DO_TEST);
566 		} else if (strcmp(command, "permprofile") == 0) {
567 			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
568 							     AA_DO_TEST);
569 		} else
570 			goto fail;
571 	} else if (strcmp(name, "exec") == 0) {
572 		if (strcmp(command, "exec") == 0)
573 			error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
574 							     !AA_DO_TEST);
575 		else
576 			goto fail;
577 	} else
578 		/* only support the "current" and "exec" process attributes */
579 		return -EINVAL;
580 
581 	if (!error)
582 		error = size;
583 	return error;
584 
585 fail:
586 	sa.type = LSM_AUDIT_DATA_NONE;
587 	sa.aad = &aad;
588 	aad.profile = aa_current_profile();
589 	aad.op = OP_SETPROCATTR;
590 	aad.info = name;
591 	aad.error = -EINVAL;
592 	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
593 	return -EINVAL;
594 }
595 
596 static int apparmor_task_setrlimit(struct task_struct *task,
597 		unsigned int resource, struct rlimit *new_rlim)
598 {
599 	struct aa_profile *profile = __aa_current_profile();
600 	int error = 0;
601 
602 	if (!unconfined(profile))
603 		error = aa_task_setrlimit(profile, task, resource, new_rlim);
604 
605 	return error;
606 }
607 
608 static struct security_hook_list apparmor_hooks[] = {
609 	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
610 	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
611 	LSM_HOOK_INIT(capget, apparmor_capget),
612 	LSM_HOOK_INIT(capable, apparmor_capable),
613 
614 	LSM_HOOK_INIT(path_link, apparmor_path_link),
615 	LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
616 	LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
617 	LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
618 	LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
619 	LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
620 	LSM_HOOK_INIT(path_rename, apparmor_path_rename),
621 	LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
622 	LSM_HOOK_INIT(path_chown, apparmor_path_chown),
623 	LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
624 	LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
625 
626 	LSM_HOOK_INIT(file_open, apparmor_file_open),
627 	LSM_HOOK_INIT(file_permission, apparmor_file_permission),
628 	LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
629 	LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
630 	LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
631 	LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
632 	LSM_HOOK_INIT(file_lock, apparmor_file_lock),
633 
634 	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
635 	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
636 
637 	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
638 	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
639 	LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
640 	LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
641 
642 	LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
643 	LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
644 	LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
645 	LSM_HOOK_INIT(bprm_secureexec, apparmor_bprm_secureexec),
646 
647 	LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
648 };
649 
650 /*
651  * AppArmor sysfs module parameters
652  */
653 
654 static int param_set_aabool(const char *val, const struct kernel_param *kp);
655 static int param_get_aabool(char *buffer, const struct kernel_param *kp);
656 #define param_check_aabool param_check_bool
657 static const struct kernel_param_ops param_ops_aabool = {
658 	.flags = KERNEL_PARAM_OPS_FL_NOARG,
659 	.set = param_set_aabool,
660 	.get = param_get_aabool
661 };
662 
663 static int param_set_aauint(const char *val, const struct kernel_param *kp);
664 static int param_get_aauint(char *buffer, const struct kernel_param *kp);
665 #define param_check_aauint param_check_uint
666 static const struct kernel_param_ops param_ops_aauint = {
667 	.set = param_set_aauint,
668 	.get = param_get_aauint
669 };
670 
671 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
672 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
673 #define param_check_aalockpolicy param_check_bool
674 static const struct kernel_param_ops param_ops_aalockpolicy = {
675 	.flags = KERNEL_PARAM_OPS_FL_NOARG,
676 	.set = param_set_aalockpolicy,
677 	.get = param_get_aalockpolicy
678 };
679 
680 static int param_set_audit(const char *val, struct kernel_param *kp);
681 static int param_get_audit(char *buffer, struct kernel_param *kp);
682 
683 static int param_set_mode(const char *val, struct kernel_param *kp);
684 static int param_get_mode(char *buffer, struct kernel_param *kp);
685 
686 /* Flag values, also controllable via /sys/module/apparmor/parameters
687  * We define special types as we want to do additional mediation.
688  */
689 
690 /* AppArmor global enforcement switch - complain, enforce, kill */
691 enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
692 module_param_call(mode, param_set_mode, param_get_mode,
693 		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
694 
695 /* Debug mode */
696 bool aa_g_debug;
697 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
698 
699 /* Audit mode */
700 enum audit_mode aa_g_audit;
701 module_param_call(audit, param_set_audit, param_get_audit,
702 		  &aa_g_audit, S_IRUSR | S_IWUSR);
703 
704 /* Determines if audit header is included in audited messages.  This
705  * provides more context if the audit daemon is not running
706  */
707 bool aa_g_audit_header = 1;
708 module_param_named(audit_header, aa_g_audit_header, aabool,
709 		   S_IRUSR | S_IWUSR);
710 
711 /* lock out loading/removal of policy
712  * TODO: add in at boot loading of policy, which is the only way to
713  *       load policy, if lock_policy is set
714  */
715 bool aa_g_lock_policy;
716 module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
717 		   S_IRUSR | S_IWUSR);
718 
719 /* Syscall logging mode */
720 bool aa_g_logsyscall;
721 module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
722 
723 /* Maximum pathname length before accesses will start getting rejected */
724 unsigned int aa_g_path_max = 2 * PATH_MAX;
725 module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
726 
727 /* Determines how paranoid loading of policy is and how much verification
728  * on the loaded policy is done.
729  */
730 bool aa_g_paranoid_load = 1;
731 module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
732 		   S_IRUSR | S_IWUSR);
733 
734 /* Boot time disable flag */
735 static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
736 module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
737 
738 static int __init apparmor_enabled_setup(char *str)
739 {
740 	unsigned long enabled;
741 	int error = kstrtoul(str, 0, &enabled);
742 	if (!error)
743 		apparmor_enabled = enabled ? 1 : 0;
744 	return 1;
745 }
746 
747 __setup("apparmor=", apparmor_enabled_setup);
748 
749 /* set global flag turning off the ability to load policy */
750 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
751 {
752 	if (!capable(CAP_MAC_ADMIN))
753 		return -EPERM;
754 	if (aa_g_lock_policy)
755 		return -EACCES;
756 	return param_set_bool(val, kp);
757 }
758 
759 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
760 {
761 	if (!capable(CAP_MAC_ADMIN))
762 		return -EPERM;
763 	return param_get_bool(buffer, kp);
764 }
765 
766 static int param_set_aabool(const char *val, const struct kernel_param *kp)
767 {
768 	if (!capable(CAP_MAC_ADMIN))
769 		return -EPERM;
770 	return param_set_bool(val, kp);
771 }
772 
773 static int param_get_aabool(char *buffer, const struct kernel_param *kp)
774 {
775 	if (!capable(CAP_MAC_ADMIN))
776 		return -EPERM;
777 	return param_get_bool(buffer, kp);
778 }
779 
780 static int param_set_aauint(const char *val, const struct kernel_param *kp)
781 {
782 	if (!capable(CAP_MAC_ADMIN))
783 		return -EPERM;
784 	return param_set_uint(val, kp);
785 }
786 
787 static int param_get_aauint(char *buffer, const struct kernel_param *kp)
788 {
789 	if (!capable(CAP_MAC_ADMIN))
790 		return -EPERM;
791 	return param_get_uint(buffer, kp);
792 }
793 
794 static int param_get_audit(char *buffer, struct kernel_param *kp)
795 {
796 	if (!capable(CAP_MAC_ADMIN))
797 		return -EPERM;
798 
799 	if (!apparmor_enabled)
800 		return -EINVAL;
801 
802 	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
803 }
804 
805 static int param_set_audit(const char *val, struct kernel_param *kp)
806 {
807 	int i;
808 	if (!capable(CAP_MAC_ADMIN))
809 		return -EPERM;
810 
811 	if (!apparmor_enabled)
812 		return -EINVAL;
813 
814 	if (!val)
815 		return -EINVAL;
816 
817 	for (i = 0; i < AUDIT_MAX_INDEX; i++) {
818 		if (strcmp(val, audit_mode_names[i]) == 0) {
819 			aa_g_audit = i;
820 			return 0;
821 		}
822 	}
823 
824 	return -EINVAL;
825 }
826 
827 static int param_get_mode(char *buffer, struct kernel_param *kp)
828 {
829 	if (!capable(CAP_MAC_ADMIN))
830 		return -EPERM;
831 
832 	if (!apparmor_enabled)
833 		return -EINVAL;
834 
835 	return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
836 }
837 
838 static int param_set_mode(const char *val, struct kernel_param *kp)
839 {
840 	int i;
841 	if (!capable(CAP_MAC_ADMIN))
842 		return -EPERM;
843 
844 	if (!apparmor_enabled)
845 		return -EINVAL;
846 
847 	if (!val)
848 		return -EINVAL;
849 
850 	for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
851 		if (strcmp(val, aa_profile_mode_names[i]) == 0) {
852 			aa_g_profile_mode = i;
853 			return 0;
854 		}
855 	}
856 
857 	return -EINVAL;
858 }
859 
860 /*
861  * AppArmor init functions
862  */
863 
864 /**
865  * set_init_cxt - set a task context and profile on the first task.
866  *
867  * TODO: allow setting an alternate profile than unconfined
868  */
869 static int __init set_init_cxt(void)
870 {
871 	struct cred *cred = (struct cred *)current->real_cred;
872 	struct aa_task_cxt *cxt;
873 
874 	cxt = aa_alloc_task_context(GFP_KERNEL);
875 	if (!cxt)
876 		return -ENOMEM;
877 
878 	cxt->profile = aa_get_profile(root_ns->unconfined);
879 	cred_cxt(cred) = cxt;
880 
881 	return 0;
882 }
883 
884 static int __init apparmor_init(void)
885 {
886 	int error;
887 
888 	if (!apparmor_enabled || !security_module_enable("apparmor")) {
889 		aa_info_message("AppArmor disabled by boot time parameter");
890 		apparmor_enabled = 0;
891 		return 0;
892 	}
893 
894 	error = aa_alloc_root_ns();
895 	if (error) {
896 		AA_ERROR("Unable to allocate default profile namespace\n");
897 		goto alloc_out;
898 	}
899 
900 	error = set_init_cxt();
901 	if (error) {
902 		AA_ERROR("Failed to set context on init task\n");
903 		aa_free_root_ns();
904 		goto alloc_out;
905 	}
906 	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks));
907 
908 	/* Report that AppArmor successfully initialized */
909 	apparmor_initialized = 1;
910 	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
911 		aa_info_message("AppArmor initialized: complain mode enabled");
912 	else if (aa_g_profile_mode == APPARMOR_KILL)
913 		aa_info_message("AppArmor initialized: kill mode enabled");
914 	else
915 		aa_info_message("AppArmor initialized");
916 
917 	return error;
918 
919 alloc_out:
920 	aa_destroy_aafs();
921 
922 	apparmor_enabled = 0;
923 	return error;
924 }
925 
926 security_initcall(apparmor_init);
927