• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/security.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  */
apparmor_cred_free(struct cred * cred)49 static void apparmor_cred_free(struct cred *cred)
50 {
51 	aa_free_task_context(cred->security);
52 	cred->security = NULL;
53 }
54 
55 /*
56  * allocate the apparmor part of blank credentials
57  */
apparmor_cred_alloc_blank(struct cred * cred,gfp_t gfp)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->security = cxt;
66 	return 0;
67 }
68 
69 /*
70  * prepare new aa_task_cxt for modification by prepare_cred block
71  */
apparmor_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)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, old->security);
81 	new->security = cxt;
82 	return 0;
83 }
84 
85 /*
86  * transfer the apparmor data to a blank set of creds
87  */
apparmor_cred_transfer(struct cred * new,const struct cred * old)88 static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
89 {
90 	const struct aa_task_cxt *old_cxt = old->security;
91 	struct aa_task_cxt *new_cxt = new->security;
92 
93 	aa_dup_task_context(new_cxt, old_cxt);
94 }
95 
apparmor_ptrace_access_check(struct task_struct * child,unsigned int mode)96 static int apparmor_ptrace_access_check(struct task_struct *child,
97 					unsigned int mode)
98 {
99 	int error = cap_ptrace_access_check(child, mode);
100 	if (error)
101 		return error;
102 
103 	return aa_ptrace(current, child, mode);
104 }
105 
apparmor_ptrace_traceme(struct task_struct * parent)106 static int apparmor_ptrace_traceme(struct task_struct *parent)
107 {
108 	int error = cap_ptrace_traceme(parent);
109 	if (error)
110 		return error;
111 
112 	return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
113 }
114 
115 /* Derived from security/commoncap.c:cap_capget */
apparmor_capget(struct task_struct * target,kernel_cap_t * effective,kernel_cap_t * inheritable,kernel_cap_t * permitted)116 static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
117 			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
118 {
119 	struct aa_profile *profile;
120 	const struct cred *cred;
121 
122 	rcu_read_lock();
123 	cred = __task_cred(target);
124 	profile = aa_cred_profile(cred);
125 
126 	*effective = cred->cap_effective;
127 	*inheritable = cred->cap_inheritable;
128 	*permitted = cred->cap_permitted;
129 
130 	if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
131 		*effective = cap_intersect(*effective, profile->caps.allow);
132 		*permitted = cap_intersect(*permitted, profile->caps.allow);
133 	}
134 	rcu_read_unlock();
135 
136 	return 0;
137 }
138 
apparmor_capable(const struct cred * cred,struct user_namespace * ns,int cap,int audit)139 static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
140 			    int cap, int audit)
141 {
142 	struct aa_profile *profile;
143 	/* cap_capable returns 0 on success, else -EPERM */
144 	int error = cap_capable(cred, ns, cap, audit);
145 	if (!error) {
146 		profile = aa_cred_profile(cred);
147 		if (!unconfined(profile))
148 			error = aa_capable(current, profile, cap, audit);
149 	}
150 	return error;
151 }
152 
153 /**
154  * common_perm - basic common permission check wrapper fn for paths
155  * @op: operation being checked
156  * @path: path to check permission of  (NOT NULL)
157  * @mask: requested permissions mask
158  * @cond: conditional info for the permission request  (NOT NULL)
159  *
160  * Returns: %0 else error code if error or permission denied
161  */
common_perm(int op,struct path * path,u32 mask,struct path_cond * cond)162 static int common_perm(int op, struct path *path, u32 mask,
163 		       struct path_cond *cond)
164 {
165 	struct aa_profile *profile;
166 	int error = 0;
167 
168 	profile = __aa_current_profile();
169 	if (!unconfined(profile))
170 		error = aa_path_perm(op, profile, path, 0, mask, cond);
171 
172 	return error;
173 }
174 
175 /**
176  * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
177  * @op: operation being checked
178  * @dir: directory of the dentry  (NOT NULL)
179  * @dentry: dentry to check  (NOT NULL)
180  * @mask: requested permissions mask
181  * @cond: conditional info for the permission request  (NOT NULL)
182  *
183  * Returns: %0 else error code if error or permission denied
184  */
common_perm_dir_dentry(int op,struct path * dir,struct dentry * dentry,u32 mask,struct path_cond * cond)185 static int common_perm_dir_dentry(int op, struct path *dir,
186 				  struct dentry *dentry, u32 mask,
187 				  struct path_cond *cond)
188 {
189 	struct path path = { dir->mnt, dentry };
190 
191 	return common_perm(op, &path, mask, cond);
192 }
193 
194 /**
195  * common_perm_mnt_dentry - common permission wrapper when mnt, dentry
196  * @op: operation being checked
197  * @mnt: mount point of dentry (NOT NULL)
198  * @dentry: dentry to check  (NOT NULL)
199  * @mask: requested permissions mask
200  *
201  * Returns: %0 else error code if error or permission denied
202  */
common_perm_mnt_dentry(int op,struct vfsmount * mnt,struct dentry * dentry,u32 mask)203 static int common_perm_mnt_dentry(int op, struct vfsmount *mnt,
204 				  struct dentry *dentry, u32 mask)
205 {
206 	struct path path = { mnt, dentry };
207 	struct path_cond cond = { dentry->d_inode->i_uid,
208 				  dentry->d_inode->i_mode
209 	};
210 
211 	return common_perm(op, &path, mask, &cond);
212 }
213 
214 /**
215  * common_perm_rm - common permission wrapper for operations doing rm
216  * @op: operation being checked
217  * @dir: directory that the dentry is in  (NOT NULL)
218  * @dentry: dentry being rm'd  (NOT NULL)
219  * @mask: requested permission mask
220  *
221  * Returns: %0 else error code if error or permission denied
222  */
common_perm_rm(int op,struct path * dir,struct dentry * dentry,u32 mask)223 static int common_perm_rm(int op, struct path *dir,
224 			  struct dentry *dentry, u32 mask)
225 {
226 	struct inode *inode = dentry->d_inode;
227 	struct path_cond cond = { };
228 
229 	if (!inode || !dir->mnt || !mediated_filesystem(inode))
230 		return 0;
231 
232 	cond.uid = inode->i_uid;
233 	cond.mode = inode->i_mode;
234 
235 	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
236 }
237 
238 /**
239  * common_perm_create - common permission wrapper for operations doing create
240  * @op: operation being checked
241  * @dir: directory that dentry will be created in  (NOT NULL)
242  * @dentry: dentry to create   (NOT NULL)
243  * @mask: request permission mask
244  * @mode: created file mode
245  *
246  * Returns: %0 else error code if error or permission denied
247  */
common_perm_create(int op,struct path * dir,struct dentry * dentry,u32 mask,umode_t mode)248 static int common_perm_create(int op, struct path *dir, struct dentry *dentry,
249 			      u32 mask, umode_t mode)
250 {
251 	struct path_cond cond = { current_fsuid(), mode };
252 
253 	if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode))
254 		return 0;
255 
256 	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
257 }
258 
apparmor_path_unlink(struct path * dir,struct dentry * dentry)259 static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
260 {
261 	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
262 }
263 
apparmor_path_mkdir(struct path * dir,struct dentry * dentry,umode_t mode)264 static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
265 			       umode_t mode)
266 {
267 	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
268 				  S_IFDIR);
269 }
270 
apparmor_path_rmdir(struct path * dir,struct dentry * dentry)271 static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
272 {
273 	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
274 }
275 
apparmor_path_mknod(struct path * dir,struct dentry * dentry,umode_t mode,unsigned int dev)276 static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
277 			       umode_t mode, unsigned int dev)
278 {
279 	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
280 }
281 
apparmor_path_truncate(struct path * path)282 static int apparmor_path_truncate(struct path *path)
283 {
284 	struct path_cond cond = { path->dentry->d_inode->i_uid,
285 				  path->dentry->d_inode->i_mode
286 	};
287 
288 	if (!path->mnt || !mediated_filesystem(path->dentry->d_inode))
289 		return 0;
290 
291 	return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE,
292 			   &cond);
293 }
294 
apparmor_path_symlink(struct path * dir,struct dentry * dentry,const char * old_name)295 static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
296 				 const char *old_name)
297 {
298 	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
299 				  S_IFLNK);
300 }
301 
apparmor_path_link(struct dentry * old_dentry,struct path * new_dir,struct dentry * new_dentry)302 static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir,
303 			      struct dentry *new_dentry)
304 {
305 	struct aa_profile *profile;
306 	int error = 0;
307 
308 	if (!mediated_filesystem(old_dentry->d_inode))
309 		return 0;
310 
311 	profile = aa_current_profile();
312 	if (!unconfined(profile))
313 		error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
314 	return error;
315 }
316 
apparmor_path_rename(struct path * old_dir,struct dentry * old_dentry,struct path * new_dir,struct dentry * new_dentry)317 static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry,
318 				struct path *new_dir, struct dentry *new_dentry)
319 {
320 	struct aa_profile *profile;
321 	int error = 0;
322 
323 	if (!mediated_filesystem(old_dentry->d_inode))
324 		return 0;
325 
326 	profile = aa_current_profile();
327 	if (!unconfined(profile)) {
328 		struct path old_path = { old_dir->mnt, old_dentry };
329 		struct path new_path = { new_dir->mnt, new_dentry };
330 		struct path_cond cond = { old_dentry->d_inode->i_uid,
331 					  old_dentry->d_inode->i_mode
332 		};
333 
334 		error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
335 				     MAY_READ | AA_MAY_META_READ | MAY_WRITE |
336 				     AA_MAY_META_WRITE | AA_MAY_DELETE,
337 				     &cond);
338 		if (!error)
339 			error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
340 					     0, MAY_WRITE | AA_MAY_META_WRITE |
341 					     AA_MAY_CREATE, &cond);
342 
343 	}
344 	return error;
345 }
346 
apparmor_path_chmod(struct path * path,umode_t mode)347 static int apparmor_path_chmod(struct path *path, umode_t mode)
348 {
349 	if (!mediated_filesystem(path->dentry->d_inode))
350 		return 0;
351 
352 	return common_perm_mnt_dentry(OP_CHMOD, path->mnt, path->dentry, AA_MAY_CHMOD);
353 }
354 
apparmor_path_chown(struct path * path,kuid_t uid,kgid_t gid)355 static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid)
356 {
357 	struct path_cond cond =  { path->dentry->d_inode->i_uid,
358 				   path->dentry->d_inode->i_mode
359 	};
360 
361 	if (!mediated_filesystem(path->dentry->d_inode))
362 		return 0;
363 
364 	return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
365 }
366 
apparmor_inode_getattr(struct vfsmount * mnt,struct dentry * dentry)367 static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
368 {
369 	if (!mediated_filesystem(dentry->d_inode))
370 		return 0;
371 
372 	return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry,
373 				      AA_MAY_META_READ);
374 }
375 
apparmor_file_open(struct file * file,const struct cred * cred)376 static int apparmor_file_open(struct file *file, const struct cred *cred)
377 {
378 	struct aa_file_cxt *fcxt = file->f_security;
379 	struct aa_profile *profile;
380 	int error = 0;
381 
382 	if (!mediated_filesystem(file_inode(file)))
383 		return 0;
384 
385 	/* If in exec, permission is handled by bprm hooks.
386 	 * Cache permissions granted by the previous exec check, with
387 	 * implicit read and executable mmap which are required to
388 	 * actually execute the image.
389 	 */
390 	if (current->in_execve) {
391 		fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
392 		return 0;
393 	}
394 
395 	profile = aa_cred_profile(cred);
396 	if (!unconfined(profile)) {
397 		struct inode *inode = file_inode(file);
398 		struct path_cond cond = { inode->i_uid, inode->i_mode };
399 
400 		error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
401 				     aa_map_file_to_perms(file), &cond);
402 		/* todo cache full allowed permissions set and state */
403 		fcxt->allow = aa_map_file_to_perms(file);
404 	}
405 
406 	return error;
407 }
408 
apparmor_file_alloc_security(struct file * file)409 static int apparmor_file_alloc_security(struct file *file)
410 {
411 	/* freed by apparmor_file_free_security */
412 	file->f_security = aa_alloc_file_context(GFP_KERNEL);
413 	if (!file->f_security)
414 		return -ENOMEM;
415 	return 0;
416 
417 }
418 
apparmor_file_free_security(struct file * file)419 static void apparmor_file_free_security(struct file *file)
420 {
421 	struct aa_file_cxt *cxt = file->f_security;
422 
423 	aa_free_file_context(cxt);
424 }
425 
common_file_perm(int op,struct file * file,u32 mask)426 static int common_file_perm(int op, struct file *file, u32 mask)
427 {
428 	struct aa_file_cxt *fcxt = file->f_security;
429 	struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
430 	int error = 0;
431 
432 	BUG_ON(!fprofile);
433 
434 	if (!file->f_path.mnt ||
435 	    !mediated_filesystem(file_inode(file)))
436 		return 0;
437 
438 	profile = __aa_current_profile();
439 
440 	/* revalidate access, if task is unconfined, or the cached cred
441 	 * doesn't match or if the request is for more permissions than
442 	 * was granted.
443 	 *
444 	 * Note: the test for !unconfined(fprofile) is to handle file
445 	 *       delegation from unconfined tasks
446 	 */
447 	if (!unconfined(profile) && !unconfined(fprofile) &&
448 	    ((fprofile != profile) || (mask & ~fcxt->allow)))
449 		error = aa_file_perm(op, profile, file, mask);
450 
451 	return error;
452 }
453 
apparmor_file_permission(struct file * file,int mask)454 static int apparmor_file_permission(struct file *file, int mask)
455 {
456 	return common_file_perm(OP_FPERM, file, mask);
457 }
458 
apparmor_file_lock(struct file * file,unsigned int cmd)459 static int apparmor_file_lock(struct file *file, unsigned int cmd)
460 {
461 	u32 mask = AA_MAY_LOCK;
462 
463 	if (cmd == F_WRLCK)
464 		mask |= MAY_WRITE;
465 
466 	return common_file_perm(OP_FLOCK, file, mask);
467 }
468 
common_mmap(int op,struct file * file,unsigned long prot,unsigned long flags)469 static int common_mmap(int op, struct file *file, unsigned long prot,
470 		       unsigned long flags)
471 {
472 	struct dentry *dentry;
473 	int mask = 0;
474 
475 	if (!file || !file->f_security)
476 		return 0;
477 
478 	if (prot & PROT_READ)
479 		mask |= MAY_READ;
480 	/*
481 	 * Private mappings don't require write perms since they don't
482 	 * write back to the files
483 	 */
484 	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
485 		mask |= MAY_WRITE;
486 	if (prot & PROT_EXEC)
487 		mask |= AA_EXEC_MMAP;
488 
489 	dentry = file->f_path.dentry;
490 	return common_file_perm(op, file, mask);
491 }
492 
apparmor_mmap_file(struct file * file,unsigned long reqprot,unsigned long prot,unsigned long flags)493 static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
494 			      unsigned long prot, unsigned long flags)
495 {
496 	return common_mmap(OP_FMMAP, file, prot, flags);
497 }
498 
apparmor_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot)499 static int apparmor_file_mprotect(struct vm_area_struct *vma,
500 				  unsigned long reqprot, unsigned long prot)
501 {
502 	return common_mmap(OP_FMPROT, vma->vm_file, prot,
503 			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
504 }
505 
apparmor_getprocattr(struct task_struct * task,char * name,char ** value)506 static int apparmor_getprocattr(struct task_struct *task, char *name,
507 				char **value)
508 {
509 	int error = -ENOENT;
510 	struct aa_profile *profile;
511 	/* released below */
512 	const struct cred *cred = get_task_cred(task);
513 	struct aa_task_cxt *cxt = cred->security;
514 	profile = aa_cred_profile(cred);
515 
516 	if (strcmp(name, "current") == 0)
517 		error = aa_getprocattr(aa_newest_version(cxt->profile),
518 				       value);
519 	else if (strcmp(name, "prev") == 0  && cxt->previous)
520 		error = aa_getprocattr(aa_newest_version(cxt->previous),
521 				       value);
522 	else if (strcmp(name, "exec") == 0 && cxt->onexec)
523 		error = aa_getprocattr(aa_newest_version(cxt->onexec),
524 				       value);
525 	else
526 		error = -EINVAL;
527 
528 	put_cred(cred);
529 
530 	return error;
531 }
532 
apparmor_setprocattr(struct task_struct * task,char * name,void * value,size_t size)533 static int apparmor_setprocattr(struct task_struct *task, char *name,
534 				void *value, size_t size)
535 {
536 	char *command, *args = value;
537 	size_t arg_size;
538 	int error;
539 
540 	if (size == 0)
541 		return -EINVAL;
542 	/* args points to a PAGE_SIZE buffer, AppArmor requires that
543 	 * the buffer must be null terminated or have size <= PAGE_SIZE -1
544 	 * so that AppArmor can null terminate them
545 	 */
546 	if (args[size - 1] != '\0') {
547 		if (size == PAGE_SIZE)
548 			return -EINVAL;
549 		args[size] = '\0';
550 	}
551 
552 	/* task can only write its own attributes */
553 	if (current != task)
554 		return -EACCES;
555 
556 	args = value;
557 	args = strim(args);
558 	command = strsep(&args, " ");
559 	if (!args)
560 		return -EINVAL;
561 	args = skip_spaces(args);
562 	if (!*args)
563 		return -EINVAL;
564 
565 	arg_size = size - (args - (char *) value);
566 	if (strcmp(name, "current") == 0) {
567 		if (strcmp(command, "changehat") == 0) {
568 			error = aa_setprocattr_changehat(args, arg_size,
569 							 !AA_DO_TEST);
570 		} else if (strcmp(command, "permhat") == 0) {
571 			error = aa_setprocattr_changehat(args, arg_size,
572 							 AA_DO_TEST);
573 		} else if (strcmp(command, "changeprofile") == 0) {
574 			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
575 							     !AA_DO_TEST);
576 		} else if (strcmp(command, "permprofile") == 0) {
577 			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
578 							     AA_DO_TEST);
579 		} else if (strcmp(command, "permipc") == 0) {
580 			error = aa_setprocattr_permipc(args);
581 		} else {
582 			struct common_audit_data sa;
583 			struct apparmor_audit_data aad = {0,};
584 			sa.type = LSM_AUDIT_DATA_NONE;
585 			sa.aad = &aad;
586 			aad.op = OP_SETPROCATTR;
587 			aad.info = name;
588 			aad.error = -EINVAL;
589 			return aa_audit(AUDIT_APPARMOR_DENIED,
590 					__aa_current_profile(), GFP_KERNEL,
591 					&sa, NULL);
592 		}
593 	} else if (strcmp(name, "exec") == 0) {
594 		error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
595 						     !AA_DO_TEST);
596 	} else {
597 		/* only support the "current" and "exec" process attributes */
598 		return -EINVAL;
599 	}
600 	if (!error)
601 		error = size;
602 	return error;
603 }
604 
apparmor_task_setrlimit(struct task_struct * task,unsigned int resource,struct rlimit * new_rlim)605 static int apparmor_task_setrlimit(struct task_struct *task,
606 		unsigned int resource, struct rlimit *new_rlim)
607 {
608 	struct aa_profile *profile = __aa_current_profile();
609 	int error = 0;
610 
611 	if (!unconfined(profile))
612 		error = aa_task_setrlimit(profile, task, resource, new_rlim);
613 
614 	return error;
615 }
616 
617 static struct security_operations apparmor_ops = {
618 	.name =				"apparmor",
619 
620 	.ptrace_access_check =		apparmor_ptrace_access_check,
621 	.ptrace_traceme =		apparmor_ptrace_traceme,
622 	.capget =			apparmor_capget,
623 	.capable =			apparmor_capable,
624 
625 	.path_link =			apparmor_path_link,
626 	.path_unlink =			apparmor_path_unlink,
627 	.path_symlink =			apparmor_path_symlink,
628 	.path_mkdir =			apparmor_path_mkdir,
629 	.path_rmdir =			apparmor_path_rmdir,
630 	.path_mknod =			apparmor_path_mknod,
631 	.path_rename =			apparmor_path_rename,
632 	.path_chmod =			apparmor_path_chmod,
633 	.path_chown =			apparmor_path_chown,
634 	.path_truncate =		apparmor_path_truncate,
635 	.inode_getattr =                apparmor_inode_getattr,
636 
637 	.file_open =			apparmor_file_open,
638 	.file_permission =		apparmor_file_permission,
639 	.file_alloc_security =		apparmor_file_alloc_security,
640 	.file_free_security =		apparmor_file_free_security,
641 	.mmap_file =			apparmor_mmap_file,
642 	.mmap_addr =			cap_mmap_addr,
643 	.file_mprotect =		apparmor_file_mprotect,
644 	.file_lock =			apparmor_file_lock,
645 
646 	.getprocattr =			apparmor_getprocattr,
647 	.setprocattr =			apparmor_setprocattr,
648 
649 	.cred_alloc_blank =		apparmor_cred_alloc_blank,
650 	.cred_free =			apparmor_cred_free,
651 	.cred_prepare =			apparmor_cred_prepare,
652 	.cred_transfer =		apparmor_cred_transfer,
653 
654 	.bprm_set_creds =		apparmor_bprm_set_creds,
655 	.bprm_committing_creds =	apparmor_bprm_committing_creds,
656 	.bprm_committed_creds =		apparmor_bprm_committed_creds,
657 	.bprm_secureexec =		apparmor_bprm_secureexec,
658 
659 	.task_setrlimit =		apparmor_task_setrlimit,
660 };
661 
662 /*
663  * AppArmor sysfs module parameters
664  */
665 
666 static int param_set_aabool(const char *val, const struct kernel_param *kp);
667 static int param_get_aabool(char *buffer, const struct kernel_param *kp);
668 #define param_check_aabool param_check_bool
669 static struct kernel_param_ops param_ops_aabool = {
670 	.set = param_set_aabool,
671 	.get = param_get_aabool
672 };
673 
674 static int param_set_aauint(const char *val, const struct kernel_param *kp);
675 static int param_get_aauint(char *buffer, const struct kernel_param *kp);
676 #define param_check_aauint param_check_uint
677 static struct kernel_param_ops param_ops_aauint = {
678 	.set = param_set_aauint,
679 	.get = param_get_aauint
680 };
681 
682 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
683 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
684 #define param_check_aalockpolicy param_check_bool
685 static struct kernel_param_ops param_ops_aalockpolicy = {
686 	.set = param_set_aalockpolicy,
687 	.get = param_get_aalockpolicy
688 };
689 
690 static int param_set_audit(const char *val, struct kernel_param *kp);
691 static int param_get_audit(char *buffer, struct kernel_param *kp);
692 
693 static int param_set_mode(const char *val, struct kernel_param *kp);
694 static int param_get_mode(char *buffer, struct kernel_param *kp);
695 
696 /* Flag values, also controllable via /sys/module/apparmor/parameters
697  * We define special types as we want to do additional mediation.
698  */
699 
700 /* AppArmor global enforcement switch - complain, enforce, kill */
701 enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
702 module_param_call(mode, param_set_mode, param_get_mode,
703 		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
704 
705 /* Debug mode */
706 bool aa_g_debug;
707 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
708 
709 /* Audit mode */
710 enum audit_mode aa_g_audit;
711 module_param_call(audit, param_set_audit, param_get_audit,
712 		  &aa_g_audit, S_IRUSR | S_IWUSR);
713 
714 /* Determines if audit header is included in audited messages.  This
715  * provides more context if the audit daemon is not running
716  */
717 bool aa_g_audit_header = 1;
718 module_param_named(audit_header, aa_g_audit_header, aabool,
719 		   S_IRUSR | S_IWUSR);
720 
721 /* lock out loading/removal of policy
722  * TODO: add in at boot loading of policy, which is the only way to
723  *       load policy, if lock_policy is set
724  */
725 bool aa_g_lock_policy;
726 module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
727 		   S_IRUSR | S_IWUSR);
728 
729 /* Syscall logging mode */
730 bool aa_g_logsyscall;
731 module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
732 
733 /* Maximum pathname length before accesses will start getting rejected */
734 unsigned int aa_g_path_max = 2 * PATH_MAX;
735 module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
736 
737 /* Determines how paranoid loading of policy is and how much verification
738  * on the loaded policy is done.
739  */
740 bool aa_g_paranoid_load = 1;
741 module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
742 		   S_IRUSR | S_IWUSR);
743 
744 /* Boot time disable flag */
745 static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
746 module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR);
747 
apparmor_enabled_setup(char * str)748 static int __init apparmor_enabled_setup(char *str)
749 {
750 	unsigned long enabled;
751 	int error = strict_strtoul(str, 0, &enabled);
752 	if (!error)
753 		apparmor_enabled = enabled ? 1 : 0;
754 	return 1;
755 }
756 
757 __setup("apparmor=", apparmor_enabled_setup);
758 
759 /* set global flag turning off the ability to load policy */
param_set_aalockpolicy(const char * val,const struct kernel_param * kp)760 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
761 {
762 	if (!capable(CAP_MAC_ADMIN))
763 		return -EPERM;
764 	if (aa_g_lock_policy)
765 		return -EACCES;
766 	return param_set_bool(val, kp);
767 }
768 
param_get_aalockpolicy(char * buffer,const struct kernel_param * kp)769 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
770 {
771 	if (!capable(CAP_MAC_ADMIN))
772 		return -EPERM;
773 	return param_get_bool(buffer, kp);
774 }
775 
param_set_aabool(const char * val,const struct kernel_param * kp)776 static int param_set_aabool(const char *val, const struct kernel_param *kp)
777 {
778 	if (!capable(CAP_MAC_ADMIN))
779 		return -EPERM;
780 	return param_set_bool(val, kp);
781 }
782 
param_get_aabool(char * buffer,const struct kernel_param * kp)783 static int param_get_aabool(char *buffer, const struct kernel_param *kp)
784 {
785 	if (!capable(CAP_MAC_ADMIN))
786 		return -EPERM;
787 	return param_get_bool(buffer, kp);
788 }
789 
param_set_aauint(const char * val,const struct kernel_param * kp)790 static int param_set_aauint(const char *val, const struct kernel_param *kp)
791 {
792 	if (!capable(CAP_MAC_ADMIN))
793 		return -EPERM;
794 	return param_set_uint(val, kp);
795 }
796 
param_get_aauint(char * buffer,const struct kernel_param * kp)797 static int param_get_aauint(char *buffer, const struct kernel_param *kp)
798 {
799 	if (!capable(CAP_MAC_ADMIN))
800 		return -EPERM;
801 	return param_get_uint(buffer, kp);
802 }
803 
param_get_audit(char * buffer,struct kernel_param * kp)804 static int param_get_audit(char *buffer, struct kernel_param *kp)
805 {
806 	if (!capable(CAP_MAC_ADMIN))
807 		return -EPERM;
808 
809 	if (!apparmor_enabled)
810 		return -EINVAL;
811 
812 	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
813 }
814 
param_set_audit(const char * val,struct kernel_param * kp)815 static int param_set_audit(const char *val, struct kernel_param *kp)
816 {
817 	int i;
818 	if (!capable(CAP_MAC_ADMIN))
819 		return -EPERM;
820 
821 	if (!apparmor_enabled)
822 		return -EINVAL;
823 
824 	if (!val)
825 		return -EINVAL;
826 
827 	for (i = 0; i < AUDIT_MAX_INDEX; i++) {
828 		if (strcmp(val, audit_mode_names[i]) == 0) {
829 			aa_g_audit = i;
830 			return 0;
831 		}
832 	}
833 
834 	return -EINVAL;
835 }
836 
param_get_mode(char * buffer,struct kernel_param * kp)837 static int param_get_mode(char *buffer, struct kernel_param *kp)
838 {
839 	if (!capable(CAP_MAC_ADMIN))
840 		return -EPERM;
841 
842 	if (!apparmor_enabled)
843 		return -EINVAL;
844 
845 	return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]);
846 }
847 
param_set_mode(const char * val,struct kernel_param * kp)848 static int param_set_mode(const char *val, struct kernel_param *kp)
849 {
850 	int i;
851 	if (!capable(CAP_MAC_ADMIN))
852 		return -EPERM;
853 
854 	if (!apparmor_enabled)
855 		return -EINVAL;
856 
857 	if (!val)
858 		return -EINVAL;
859 
860 	for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) {
861 		if (strcmp(val, profile_mode_names[i]) == 0) {
862 			aa_g_profile_mode = i;
863 			return 0;
864 		}
865 	}
866 
867 	return -EINVAL;
868 }
869 
870 /*
871  * AppArmor init functions
872  */
873 
874 /**
875  * set_init_cxt - set a task context and profile on the first task.
876  *
877  * TODO: allow setting an alternate profile than unconfined
878  */
set_init_cxt(void)879 static int __init set_init_cxt(void)
880 {
881 	struct cred *cred = (struct cred *)current->real_cred;
882 	struct aa_task_cxt *cxt;
883 
884 	cxt = aa_alloc_task_context(GFP_KERNEL);
885 	if (!cxt)
886 		return -ENOMEM;
887 
888 	cxt->profile = aa_get_profile(root_ns->unconfined);
889 	cred->security = cxt;
890 
891 	return 0;
892 }
893 
apparmor_init(void)894 static int __init apparmor_init(void)
895 {
896 	int error;
897 
898 	if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
899 		aa_info_message("AppArmor disabled by boot time parameter");
900 		apparmor_enabled = 0;
901 		return 0;
902 	}
903 
904 	error = aa_alloc_root_ns();
905 	if (error) {
906 		AA_ERROR("Unable to allocate default profile namespace\n");
907 		goto alloc_out;
908 	}
909 
910 	error = set_init_cxt();
911 	if (error) {
912 		AA_ERROR("Failed to set context on init task\n");
913 		goto register_security_out;
914 	}
915 
916 	error = register_security(&apparmor_ops);
917 	if (error) {
918 		AA_ERROR("Unable to register AppArmor\n");
919 		goto set_init_cxt_out;
920 	}
921 
922 	/* Report that AppArmor successfully initialized */
923 	apparmor_initialized = 1;
924 	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
925 		aa_info_message("AppArmor initialized: complain mode enabled");
926 	else if (aa_g_profile_mode == APPARMOR_KILL)
927 		aa_info_message("AppArmor initialized: kill mode enabled");
928 	else
929 		aa_info_message("AppArmor initialized");
930 
931 	return error;
932 
933 set_init_cxt_out:
934 	aa_free_task_context(current->real_cred->security);
935 
936 register_security_out:
937 	aa_free_root_ns();
938 
939 alloc_out:
940 	aa_destroy_aafs();
941 
942 	apparmor_enabled = 0;
943 	return error;
944 }
945 
946 security_initcall(apparmor_init);
947