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 */
40int apparmor_initialized __initdata;
41
42/*
43 * LSM hook functions
44 */
45
46/*
47 * free the associated aa_task_cxt and put its profiles
48 */
49static 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 */
58static 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 */
72static 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 */
88static 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
96static int apparmor_ptrace_access_check(struct task_struct *child,
97					unsigned int mode)
98{
99	return aa_ptrace(current, child, mode);
100}
101
102static 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 */
108static 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
131static 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 */
152static 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 */
175static 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 */
193static 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 */
213static 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 */
238static 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
249static 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
254static 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
261static 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
266static 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
272static 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
285static 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
292static 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
307static 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
337static 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
345static 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
357static 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
366static 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
399static 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
409static 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
416static 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
444static int apparmor_file_permission(struct file *file, int mask)
445{
446	return common_file_perm(OP_FPERM, file, mask);
447}
448
449static 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
459static 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
481static 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
487static 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
494static 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
521static 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
585fail:
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
596static 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
608static 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
654static int param_set_aabool(const char *val, const struct kernel_param *kp);
655static int param_get_aabool(char *buffer, const struct kernel_param *kp);
656#define param_check_aabool param_check_bool
657static 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
663static int param_set_aauint(const char *val, const struct kernel_param *kp);
664static int param_get_aauint(char *buffer, const struct kernel_param *kp);
665#define param_check_aauint param_check_uint
666static const struct kernel_param_ops param_ops_aauint = {
667	.set = param_set_aauint,
668	.get = param_get_aauint
669};
670
671static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
672static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
673#define param_check_aalockpolicy param_check_bool
674static 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
680static int param_set_audit(const char *val, struct kernel_param *kp);
681static int param_get_audit(char *buffer, struct kernel_param *kp);
682
683static int param_set_mode(const char *val, struct kernel_param *kp);
684static 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 */
691enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
692module_param_call(mode, param_set_mode, param_get_mode,
693		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
694
695/* Debug mode */
696bool aa_g_debug;
697module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
698
699/* Audit mode */
700enum audit_mode aa_g_audit;
701module_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 */
707bool aa_g_audit_header = 1;
708module_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 */
715bool aa_g_lock_policy;
716module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
717		   S_IRUSR | S_IWUSR);
718
719/* Syscall logging mode */
720bool aa_g_logsyscall;
721module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
722
723/* Maximum pathname length before accesses will start getting rejected */
724unsigned int aa_g_path_max = 2 * PATH_MAX;
725module_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 */
730bool aa_g_paranoid_load = 1;
731module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
732		   S_IRUSR | S_IWUSR);
733
734/* Boot time disable flag */
735static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
736module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
737
738static 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 */
750static 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
759static 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
766static 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
773static 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
780static 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
787static 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
794static 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
805static 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
827static 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
838static 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 */
869static 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
884static 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
919alloc_out:
920	aa_destroy_aafs();
921
922	apparmor_enabled = 0;
923	return error;
924}
925
926security_initcall(apparmor_init);
927