Linux Audio

Check our new training course

Loading...
v3.1
 
  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 */
 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->security);
 52	cred->security = 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->security = 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, old->security);
 81	new->security = 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 = old->security;
 91	struct aa_task_cxt *new_cxt = new->security;
 
 
 
 
 
 
 
 
 
 
 
 
 
 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	int error = cap_ptrace_access_check(child, mode);
100	if (error)
101		return error;
 
 
 
 
 
 
 
102
103	return aa_ptrace(current, child, mode);
104}
105
106static 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 */
116static 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
139static int apparmor_capable(struct task_struct *task, const struct cred *cred,
140			    struct user_namespace *ns, int cap, int audit)
141{
142	struct aa_profile *profile;
143	/* cap_capable returns 0 on success, else -EPERM */
144	int error = cap_capable(task, cred, ns, cap, audit);
145	if (!error) {
146		profile = aa_cred_profile(cred);
147		if (!unconfined(profile))
148			error = aa_capable(task, 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 */
162static 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 */
185static 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 */
203static 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 */
223static 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 */
248static 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
259static 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
264static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
265			       int mode)
266{
267	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
268				  S_IFDIR);
269}
270
271static 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
276static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
277			       int mode, unsigned int dev)
278{
279	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
280}
281
282static 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
295static 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
302static 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
317static 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
347static int apparmor_path_chmod(struct dentry *dentry, struct vfsmount *mnt,
348			       mode_t mode)
349{
350	if (!mediated_filesystem(dentry->d_inode))
351		return 0;
352
353	return common_perm_mnt_dentry(OP_CHMOD, mnt, dentry, AA_MAY_CHMOD);
354}
355
356static int apparmor_path_chown(struct path *path, uid_t uid, gid_t gid)
357{
358	struct path_cond cond =  { path->dentry->d_inode->i_uid,
359				   path->dentry->d_inode->i_mode
360	};
361
362	if (!mediated_filesystem(path->dentry->d_inode))
363		return 0;
364
365	return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
366}
367
368static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
369{
370	if (!mediated_filesystem(dentry->d_inode))
371		return 0;
372
373	return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry,
374				      AA_MAY_META_READ);
375}
376
377static int apparmor_dentry_open(struct file *file, const struct cred *cred)
378{
379	struct aa_file_cxt *fcxt = file->f_security;
380	struct aa_profile *profile;
381	int error = 0;
382
383	if (!mediated_filesystem(file->f_path.dentry->d_inode))
384		return 0;
385
386	/* If in exec, permission is handled by bprm hooks.
387	 * Cache permissions granted by the previous exec check, with
388	 * implicit read and executable mmap which are required to
389	 * actually execute the image.
390	 */
391	if (current->in_execve) {
392		fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
393		return 0;
394	}
395
396	profile = aa_cred_profile(cred);
397	if (!unconfined(profile)) {
398		struct inode *inode = file->f_path.dentry->d_inode;
399		struct path_cond cond = { inode->i_uid, inode->i_mode };
400
401		error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
402				     aa_map_file_to_perms(file), &cond);
403		/* todo cache full allowed permissions set and state */
404		fcxt->allow = aa_map_file_to_perms(file);
405	}
 
406
407	return error;
408}
409
410static int apparmor_file_alloc_security(struct file *file)
411{
412	/* freed by apparmor_file_free_security */
413	file->f_security = aa_alloc_file_context(GFP_KERNEL);
414	if (!file->f_security)
415		return -ENOMEM;
416	return 0;
417
 
 
 
 
418}
419
420static void apparmor_file_free_security(struct file *file)
421{
422	struct aa_file_cxt *cxt = file->f_security;
423
424	aa_free_file_context(cxt);
 
425}
426
427static int common_file_perm(int op, struct file *file, u32 mask)
 
428{
429	struct aa_file_cxt *fcxt = file->f_security;
430	struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
431	int error = 0;
432
433	BUG_ON(!fprofile);
434
435	if (!file->f_path.mnt ||
436	    !mediated_filesystem(file->f_path.dentry->d_inode))
437		return 0;
438
439	profile = __aa_current_profile();
440
441	/* revalidate access, if task is unconfined, or the cached cred
442	 * doesn't match or if the request is for more permissions than
443	 * was granted.
444	 *
445	 * Note: the test for !unconfined(fprofile) is to handle file
446	 *       delegation from unconfined tasks
447	 */
448	if (!unconfined(profile) && !unconfined(fprofile) &&
449	    ((fprofile != profile) || (mask & ~fcxt->allow)))
450		error = aa_file_perm(op, profile, file, mask);
451
452	return error;
453}
454
 
 
 
 
 
 
455static int apparmor_file_permission(struct file *file, int mask)
456{
457	return common_file_perm(OP_FPERM, file, mask);
458}
459
460static int apparmor_file_lock(struct file *file, unsigned int cmd)
461{
462	u32 mask = AA_MAY_LOCK;
463
464	if (cmd == F_WRLCK)
465		mask |= MAY_WRITE;
466
467	return common_file_perm(OP_FLOCK, file, mask);
468}
469
470static int common_mmap(int op, struct file *file, unsigned long prot,
471		       unsigned long flags)
472{
473	struct dentry *dentry;
474	int mask = 0;
475
476	if (!file || !file->f_security)
477		return 0;
478
479	if (prot & PROT_READ)
480		mask |= MAY_READ;
481	/*
482	 * Private mappings don't require write perms since they don't
483	 * write back to the files
484	 */
485	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
486		mask |= MAY_WRITE;
487	if (prot & PROT_EXEC)
488		mask |= AA_EXEC_MMAP;
489
490	dentry = file->f_path.dentry;
491	return common_file_perm(op, file, mask);
492}
493
494static int apparmor_file_mmap(struct file *file, unsigned long reqprot,
495			      unsigned long prot, unsigned long flags,
496			      unsigned long addr, unsigned long addr_only)
497{
498	int rc = 0;
499
500	/* do DAC check */
501	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
502	if (rc || addr_only)
503		return rc;
504
505	return common_mmap(OP_FMMAP, file, prot, flags);
506}
507
508static int apparmor_file_mprotect(struct vm_area_struct *vma,
509				  unsigned long reqprot, unsigned long prot)
510{
511	return common_mmap(OP_FMPROT, vma->vm_file, prot,
512			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
513}
514
515static int apparmor_getprocattr(struct task_struct *task, char *name,
516				char **value)
517{
518	int error = -ENOENT;
519	struct aa_profile *profile;
520	/* released below */
521	const struct cred *cred = get_task_cred(task);
522	struct aa_task_cxt *cxt = cred->security;
523	profile = aa_cred_profile(cred);
524
525	if (strcmp(name, "current") == 0)
526		error = aa_getprocattr(aa_newest_version(cxt->profile),
527				       value);
528	else if (strcmp(name, "prev") == 0  && cxt->previous)
529		error = aa_getprocattr(aa_newest_version(cxt->previous),
530				       value);
531	else if (strcmp(name, "exec") == 0 && cxt->onexec)
532		error = aa_getprocattr(aa_newest_version(cxt->onexec),
533				       value);
534	else
535		error = -EINVAL;
536
 
 
 
 
537	put_cred(cred);
538
539	return error;
540}
541
542static int apparmor_setprocattr(struct task_struct *task, char *name,
543				void *value, size_t size)
544{
545	char *command, *args = value;
546	size_t arg_size;
547	int error;
 
548
549	if (size == 0)
550		return -EINVAL;
551	/* args points to a PAGE_SIZE buffer, AppArmor requires that
552	 * the buffer must be null terminated or have size <= PAGE_SIZE -1
553	 * so that AppArmor can null terminate them
554	 */
555	if (args[size - 1] != '\0') {
556		if (size == PAGE_SIZE)
557			return -EINVAL;
 
 
 
558		args[size] = '\0';
559	}
560
561	/* task can only write its own attributes */
562	if (current != task)
563		return -EACCES;
564
565	args = value;
566	args = strim(args);
567	command = strsep(&args, " ");
568	if (!args)
569		return -EINVAL;
570	args = skip_spaces(args);
571	if (!*args)
572		return -EINVAL;
573
574	arg_size = size - (args - (char *) value);
575	if (strcmp(name, "current") == 0) {
576		if (strcmp(command, "changehat") == 0) {
577			error = aa_setprocattr_changehat(args, arg_size,
578							 !AA_DO_TEST);
579		} else if (strcmp(command, "permhat") == 0) {
580			error = aa_setprocattr_changehat(args, arg_size,
581							 AA_DO_TEST);
582		} else if (strcmp(command, "changeprofile") == 0) {
583			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
584							     !AA_DO_TEST);
585		} else if (strcmp(command, "permprofile") == 0) {
586			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
587							     AA_DO_TEST);
588		} else if (strcmp(command, "permipc") == 0) {
589			error = aa_setprocattr_permipc(args);
590		} else {
591			struct common_audit_data sa;
592			COMMON_AUDIT_DATA_INIT(&sa, NONE);
593			sa.aad.op = OP_SETPROCATTR;
594			sa.aad.info = name;
595			sa.aad.error = -EINVAL;
596			return aa_audit(AUDIT_APPARMOR_DENIED,
597					__aa_current_profile(), GFP_KERNEL,
598					&sa, NULL);
599		}
600	} else if (strcmp(name, "exec") == 0) {
601		error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
602						     !AA_DO_TEST);
603	} else {
 
 
 
 
 
604		/* only support the "current" and "exec" process attributes */
605		return -EINVAL;
606	}
607	if (!error)
608		error = size;
 
 
609	return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
610}
611
612static int apparmor_task_setrlimit(struct task_struct *task,
613		unsigned int resource, struct rlimit *new_rlim)
614{
615	struct aa_profile *profile = __aa_current_profile();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
616	int error = 0;
617
618	if (!unconfined(profile))
619		error = aa_task_setrlimit(profile, task, resource, new_rlim);
 
 
 
 
 
 
 
620
621	return error;
622}
623
624static struct security_operations apparmor_ops = {
625	.name =				"apparmor",
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
626
627	.ptrace_access_check =		apparmor_ptrace_access_check,
628	.ptrace_traceme =		apparmor_ptrace_traceme,
629	.capget =			apparmor_capget,
630	.capable =			apparmor_capable,
631
632	.path_link =			apparmor_path_link,
633	.path_unlink =			apparmor_path_unlink,
634	.path_symlink =			apparmor_path_symlink,
635	.path_mkdir =			apparmor_path_mkdir,
636	.path_rmdir =			apparmor_path_rmdir,
637	.path_mknod =			apparmor_path_mknod,
638	.path_rename =			apparmor_path_rename,
639	.path_chmod =			apparmor_path_chmod,
640	.path_chown =			apparmor_path_chown,
641	.path_truncate =		apparmor_path_truncate,
642	.dentry_open =			apparmor_dentry_open,
643	.inode_getattr =                apparmor_inode_getattr,
644
645	.file_permission =		apparmor_file_permission,
646	.file_alloc_security =		apparmor_file_alloc_security,
647	.file_free_security =		apparmor_file_free_security,
648	.file_mmap =			apparmor_file_mmap,
649	.file_mprotect =		apparmor_file_mprotect,
650	.file_lock =			apparmor_file_lock,
 
 
651
652	.getprocattr =			apparmor_getprocattr,
653	.setprocattr =			apparmor_setprocattr,
 
 
 
 
654
655	.cred_alloc_blank =		apparmor_cred_alloc_blank,
656	.cred_free =			apparmor_cred_free,
657	.cred_prepare =			apparmor_cred_prepare,
658	.cred_transfer =		apparmor_cred_transfer,
659
660	.bprm_set_creds =		apparmor_bprm_set_creds,
661	.bprm_committing_creds =	apparmor_bprm_committing_creds,
662	.bprm_committed_creds =		apparmor_bprm_committed_creds,
663	.bprm_secureexec =		apparmor_bprm_secureexec,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
664
665	.task_setrlimit =		apparmor_task_setrlimit,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
666};
667
668/*
669 * AppArmor sysfs module parameters
670 */
671
672static int param_set_aabool(const char *val, const struct kernel_param *kp);
673static int param_get_aabool(char *buffer, const struct kernel_param *kp);
674#define param_check_aabool(name, p) __param_check(name, p, int)
675static struct kernel_param_ops param_ops_aabool = {
 
676	.set = param_set_aabool,
677	.get = param_get_aabool
678};
679
680static int param_set_aauint(const char *val, const struct kernel_param *kp);
681static int param_get_aauint(char *buffer, const struct kernel_param *kp);
682#define param_check_aauint(name, p) __param_check(name, p, int)
683static struct kernel_param_ops param_ops_aauint = {
684	.set = param_set_aauint,
685	.get = param_get_aauint
686};
687
 
 
 
 
 
 
 
 
 
 
688static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
689static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
690#define param_check_aalockpolicy(name, p) __param_check(name, p, int)
691static struct kernel_param_ops param_ops_aalockpolicy = {
 
692	.set = param_set_aalockpolicy,
693	.get = param_get_aalockpolicy
694};
695
696static int param_set_audit(const char *val, struct kernel_param *kp);
697static int param_get_audit(char *buffer, struct kernel_param *kp);
698
699static int param_set_mode(const char *val, struct kernel_param *kp);
700static int param_get_mode(char *buffer, struct kernel_param *kp);
701
702/* Flag values, also controllable via /sys/module/apparmor/parameters
703 * We define special types as we want to do additional mediation.
704 */
705
706/* AppArmor global enforcement switch - complain, enforce, kill */
707enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
708module_param_call(mode, param_set_mode, param_get_mode,
709		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
710
 
 
 
 
 
 
 
 
 
 
 
711/* Debug mode */
712int aa_g_debug;
713module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
714
715/* Audit mode */
716enum audit_mode aa_g_audit;
717module_param_call(audit, param_set_audit, param_get_audit,
718		  &aa_g_audit, S_IRUSR | S_IWUSR);
719
720/* Determines if audit header is included in audited messages.  This
721 * provides more context if the audit daemon is not running
722 */
723int aa_g_audit_header = 1;
724module_param_named(audit_header, aa_g_audit_header, aabool,
725		   S_IRUSR | S_IWUSR);
726
727/* lock out loading/removal of policy
728 * TODO: add in at boot loading of policy, which is the only way to
729 *       load policy, if lock_policy is set
730 */
731int aa_g_lock_policy;
732module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
733		   S_IRUSR | S_IWUSR);
734
735/* Syscall logging mode */
736int aa_g_logsyscall;
737module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
738
739/* Maximum pathname length before accesses will start getting rejected */
740unsigned int aa_g_path_max = 2 * PATH_MAX;
741module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
742
743/* Determines how paranoid loading of policy is and how much verification
744 * on the loaded policy is done.
 
 
745 */
746int aa_g_paranoid_load = 1;
747module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
748		   S_IRUSR | S_IWUSR);
749
 
 
 
 
 
 
 
750/* Boot time disable flag */
751static unsigned int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
752module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR);
753
754static int __init apparmor_enabled_setup(char *str)
755{
756	unsigned long enabled;
757	int error = strict_strtoul(str, 0, &enabled);
758	if (!error)
759		apparmor_enabled = enabled ? 1 : 0;
760	return 1;
761}
762
763__setup("apparmor=", apparmor_enabled_setup);
764
765/* set global flag turning off the ability to load policy */
766static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
767{
768	if (!capable(CAP_MAC_ADMIN))
 
 
769		return -EPERM;
770	if (aa_g_lock_policy)
771		return -EACCES;
772	return param_set_bool(val, kp);
773}
774
775static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
776{
777	if (!capable(CAP_MAC_ADMIN))
 
 
778		return -EPERM;
779	return param_get_bool(buffer, kp);
780}
781
782static int param_set_aabool(const char *val, const struct kernel_param *kp)
783{
784	if (!capable(CAP_MAC_ADMIN))
 
 
785		return -EPERM;
786	return param_set_bool(val, kp);
787}
788
789static int param_get_aabool(char *buffer, const struct kernel_param *kp)
790{
791	if (!capable(CAP_MAC_ADMIN))
 
 
792		return -EPERM;
793	return param_get_bool(buffer, kp);
794}
795
796static int param_set_aauint(const char *val, const struct kernel_param *kp)
797{
798	if (!capable(CAP_MAC_ADMIN))
 
 
 
 
 
799		return -EPERM;
800	return param_set_uint(val, kp);
 
 
 
 
 
801}
802
803static int param_get_aauint(char *buffer, const struct kernel_param *kp)
804{
805	if (!capable(CAP_MAC_ADMIN))
 
 
806		return -EPERM;
807	return param_get_uint(buffer, kp);
808}
809
810static int param_get_audit(char *buffer, struct kernel_param *kp)
 
811{
812	if (!capable(CAP_MAC_ADMIN))
 
 
 
 
813		return -EPERM;
814
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
815	if (!apparmor_enabled)
816		return -EINVAL;
 
 
817
818	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
 
 
 
 
 
 
 
 
819}
820
821static int param_set_audit(const char *val, struct kernel_param *kp)
 
822{
823	int i;
824	if (!capable(CAP_MAC_ADMIN))
 
825		return -EPERM;
 
 
826
 
 
827	if (!apparmor_enabled)
828		return -EINVAL;
 
 
 
 
829
 
 
 
 
 
 
830	if (!val)
831		return -EINVAL;
 
 
832
833	for (i = 0; i < AUDIT_MAX_INDEX; i++) {
834		if (strcmp(val, audit_mode_names[i]) == 0) {
835			aa_g_audit = i;
836			return 0;
837		}
838	}
839
840	return -EINVAL;
 
841}
842
843static int param_get_mode(char *buffer, struct kernel_param *kp)
844{
845	if (!capable(CAP_MAC_ADMIN))
846		return -EPERM;
847
848	if (!apparmor_enabled)
849		return -EINVAL;
 
 
850
851	return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]);
852}
853
854static int param_set_mode(const char *val, struct kernel_param *kp)
855{
856	int i;
857	if (!capable(CAP_MAC_ADMIN))
858		return -EPERM;
859
860	if (!apparmor_enabled)
861		return -EINVAL;
862
863	if (!val)
864		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
865
866	for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) {
867		if (strcmp(val, profile_mode_names[i]) == 0) {
868			aa_g_profile_mode = i;
869			return 0;
 
 
 
870		}
 
 
871	}
 
 
 
 
 
 
 
 
 
 
872
873	return -EINVAL;
 
 
 
874}
875
876/*
877 * AppArmor init functions
878 */
879
880/**
881 * set_init_cxt - set a task context and profile on the first task.
882 *
883 * TODO: allow setting an alternate profile than unconfined
884 */
885static int __init set_init_cxt(void)
886{
887	struct cred *cred = (struct cred *)current->real_cred;
888	struct aa_task_cxt *cxt;
889
890	cxt = aa_alloc_task_context(GFP_KERNEL);
891	if (!cxt)
892		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
893
894	cxt->profile = aa_get_profile(root_ns->unconfined);
895	cred->security = cxt;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
896
897	return 0;
898}
 
 
899
900static int __init apparmor_init(void)
901{
902	int error;
903
904	if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
905		aa_info_message("AppArmor disabled by boot time parameter");
906		apparmor_enabled = 0;
907		return 0;
 
 
908	}
909
910	error = aa_alloc_root_ns();
911	if (error) {
912		AA_ERROR("Unable to allocate default profile namespace\n");
913		goto alloc_out;
914	}
915
916	error = set_init_cxt();
917	if (error) {
918		AA_ERROR("Failed to set context on init task\n");
919		goto register_security_out;
 
 
 
 
 
 
 
920	}
921
922	error = register_security(&apparmor_ops);
923	if (error) {
924		AA_ERROR("Unable to register AppArmor\n");
925		goto set_init_cxt_out;
 
926	}
 
 
927
928	/* Report that AppArmor successfully initialized */
929	apparmor_initialized = 1;
930	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
931		aa_info_message("AppArmor initialized: complain mode enabled");
932	else if (aa_g_profile_mode == APPARMOR_KILL)
933		aa_info_message("AppArmor initialized: kill mode enabled");
934	else
935		aa_info_message("AppArmor initialized");
936
937	return error;
938
939set_init_cxt_out:
940	aa_free_task_context(current->real_cred->security);
941
942register_security_out:
943	aa_free_root_ns();
944
945alloc_out:
946	aa_destroy_aafs();
 
947
948	apparmor_enabled = 0;
949	return error;
950}
951
952security_initcall(apparmor_init);
 
 
 
 
 
 
v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * AppArmor security module
   4 *
   5 * This file contains AppArmor LSM hooks.
   6 *
   7 * Copyright (C) 1998-2008 Novell/SUSE
   8 * Copyright 2009-2010 Canonical Ltd.
 
 
 
 
 
   9 */
  10
  11#include <linux/lsm_hooks.h>
  12#include <linux/moduleparam.h>
  13#include <linux/mm.h>
  14#include <linux/mman.h>
  15#include <linux/mount.h>
  16#include <linux/namei.h>
  17#include <linux/ptrace.h>
  18#include <linux/ctype.h>
  19#include <linux/sysctl.h>
  20#include <linux/audit.h>
  21#include <linux/user_namespace.h>
  22#include <linux/netfilter_ipv4.h>
  23#include <linux/netfilter_ipv6.h>
  24#include <linux/zlib.h>
  25#include <net/sock.h>
  26#include <uapi/linux/mount.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/cred.h"
  33#include "include/file.h"
  34#include "include/ipc.h"
  35#include "include/net.h"
  36#include "include/path.h"
  37#include "include/label.h"
  38#include "include/policy.h"
  39#include "include/policy_ns.h"
  40#include "include/procattr.h"
  41#include "include/mount.h"
  42#include "include/secid.h"
  43
  44/* Flag indicating whether initialization completed */
  45int apparmor_initialized;
  46
  47union aa_buffer {
  48	struct list_head list;
  49	char buffer[1];
  50};
  51
  52#define RESERVE_COUNT 2
  53static int reserve_count = RESERVE_COUNT;
  54static int buffer_count;
  55
  56static LIST_HEAD(aa_global_buffers);
  57static DEFINE_SPINLOCK(aa_buffers_lock);
  58
  59/*
  60 * LSM hook functions
  61 */
  62
  63/*
  64 * put the associated labels
  65 */
  66static void apparmor_cred_free(struct cred *cred)
  67{
  68	aa_put_label(cred_label(cred));
  69	set_cred_label(cred, NULL);
  70}
  71
  72/*
  73 * allocate the apparmor part of blank credentials
  74 */
  75static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
  76{
  77	set_cred_label(cred, NULL);
 
 
 
 
 
  78	return 0;
  79}
  80
  81/*
  82 * prepare new cred label for modification by prepare_cred block
  83 */
  84static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
  85				 gfp_t gfp)
  86{
  87	set_cred_label(new, aa_get_newest_label(cred_label(old)));
 
 
 
 
 
 
  88	return 0;
  89}
  90
  91/*
  92 * transfer the apparmor data to a blank set of creds
  93 */
  94static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
  95{
  96	set_cred_label(new, aa_get_newest_label(cred_label(old)));
  97}
  98
  99static void apparmor_task_free(struct task_struct *task)
 100{
 101
 102	aa_free_task_ctx(task_ctx(task));
 103}
 104
 105static int apparmor_task_alloc(struct task_struct *task,
 106			       unsigned long clone_flags)
 107{
 108	struct aa_task_ctx *new = task_ctx(task);
 109
 110	aa_dup_task_ctx(new, task_ctx(current));
 111
 112	return 0;
 113}
 114
 115static int apparmor_ptrace_access_check(struct task_struct *child,
 116					unsigned int mode)
 117{
 118	struct aa_label *tracer, *tracee;
 119	int error;
 120
 121	tracer = __begin_current_label_crit_section();
 122	tracee = aa_get_task_label(child);
 123	error = aa_may_ptrace(tracer, tracee,
 124			(mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
 125						  : AA_PTRACE_TRACE);
 126	aa_put_label(tracee);
 127	__end_current_label_crit_section(tracer);
 128
 129	return error;
 130}
 131
 132static int apparmor_ptrace_traceme(struct task_struct *parent)
 133{
 134	struct aa_label *tracer, *tracee;
 135	int error;
 136
 137	tracee = __begin_current_label_crit_section();
 138	tracer = aa_get_task_label(parent);
 139	error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
 140	aa_put_label(tracer);
 141	__end_current_label_crit_section(tracee);
 142
 143	return error;
 144}
 145
 146/* Derived from security/commoncap.c:cap_capget */
 147static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
 148			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
 149{
 150	struct aa_label *label;
 151	const struct cred *cred;
 152
 153	rcu_read_lock();
 154	cred = __task_cred(target);
 155	label = aa_get_newest_cred_label(cred);
 156
 157	/*
 158	 * cap_capget is stacked ahead of this and will
 159	 * initialize effective and permitted.
 160	 */
 161	if (!unconfined(label)) {
 162		struct aa_profile *profile;
 163		struct label_it i;
 164
 165		label_for_each_confined(i, label, profile) {
 166			if (COMPLAIN_MODE(profile))
 167				continue;
 168			*effective = cap_intersect(*effective,
 169						   profile->caps.allow);
 170			*permitted = cap_intersect(*permitted,
 171						   profile->caps.allow);
 172		}
 173	}
 174	rcu_read_unlock();
 175	aa_put_label(label);
 176
 177	return 0;
 178}
 179
 180static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
 181			    int cap, unsigned int opts)
 182{
 183	struct aa_label *label;
 184	int error = 0;
 185
 186	label = aa_get_newest_cred_label(cred);
 187	if (!unconfined(label))
 188		error = aa_capable(label, cap, opts);
 189	aa_put_label(label);
 190
 191	return error;
 192}
 193
 194/**
 195 * common_perm - basic common permission check wrapper fn for paths
 196 * @op: operation being checked
 197 * @path: path to check permission of  (NOT NULL)
 198 * @mask: requested permissions mask
 199 * @cond: conditional info for the permission request  (NOT NULL)
 200 *
 201 * Returns: %0 else error code if error or permission denied
 202 */
 203static int common_perm(const char *op, const struct path *path, u32 mask,
 204		       struct path_cond *cond)
 205{
 206	struct aa_label *label;
 207	int error = 0;
 208
 209	label = __begin_current_label_crit_section();
 210	if (!unconfined(label))
 211		error = aa_path_perm(op, label, path, 0, mask, cond);
 212	__end_current_label_crit_section(label);
 213
 214	return error;
 215}
 216
 217/**
 218 * common_perm_cond - common permission wrapper around inode cond
 219 * @op: operation being checked
 220 * @path: location to check (NOT NULL)
 
 221 * @mask: requested permissions mask
 
 222 *
 223 * Returns: %0 else error code if error or permission denied
 224 */
 225static int common_perm_cond(const char *op, const struct path *path, u32 mask)
 
 
 226{
 227	struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
 228				  d_backing_inode(path->dentry)->i_mode
 229	};
 230
 231	if (!path_mediated_fs(path->dentry))
 232		return 0;
 233
 234	return common_perm(op, path, mask, &cond);
 235}
 236
 237/**
 238 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
 239 * @op: operation being checked
 240 * @dir: directory of the dentry  (NOT NULL)
 241 * @dentry: dentry to check  (NOT NULL)
 242 * @mask: requested permissions mask
 243 * @cond: conditional info for the permission request  (NOT NULL)
 244 *
 245 * Returns: %0 else error code if error or permission denied
 246 */
 247static int common_perm_dir_dentry(const char *op, const struct path *dir,
 248				  struct dentry *dentry, u32 mask,
 249				  struct path_cond *cond)
 250{
 251	struct path path = { .mnt = dir->mnt, .dentry = dentry };
 
 
 
 252
 253	return common_perm(op, &path, mask, cond);
 254}
 255
 256/**
 257 * common_perm_rm - common permission wrapper for operations doing rm
 258 * @op: operation being checked
 259 * @dir: directory that the dentry is in  (NOT NULL)
 260 * @dentry: dentry being rm'd  (NOT NULL)
 261 * @mask: requested permission mask
 262 *
 263 * Returns: %0 else error code if error or permission denied
 264 */
 265static int common_perm_rm(const char *op, const struct path *dir,
 266			  struct dentry *dentry, u32 mask)
 267{
 268	struct inode *inode = d_backing_inode(dentry);
 269	struct path_cond cond = { };
 270
 271	if (!inode || !path_mediated_fs(dentry))
 272		return 0;
 273
 274	cond.uid = inode->i_uid;
 275	cond.mode = inode->i_mode;
 276
 277	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 278}
 279
 280/**
 281 * common_perm_create - common permission wrapper for operations doing create
 282 * @op: operation being checked
 283 * @dir: directory that dentry will be created in  (NOT NULL)
 284 * @dentry: dentry to create   (NOT NULL)
 285 * @mask: request permission mask
 286 * @mode: created file mode
 287 *
 288 * Returns: %0 else error code if error or permission denied
 289 */
 290static int common_perm_create(const char *op, const struct path *dir,
 291			      struct dentry *dentry, u32 mask, umode_t mode)
 292{
 293	struct path_cond cond = { current_fsuid(), mode };
 294
 295	if (!path_mediated_fs(dir->dentry))
 296		return 0;
 297
 298	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 299}
 300
 301static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
 302{
 303	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
 304}
 305
 306static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
 307			       umode_t mode)
 308{
 309	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
 310				  S_IFDIR);
 311}
 312
 313static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
 314{
 315	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
 316}
 317
 318static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
 319			       umode_t mode, unsigned int dev)
 320{
 321	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
 322}
 323
 324static int apparmor_path_truncate(const struct path *path)
 325{
 326	return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
 
 
 
 
 
 
 
 
 327}
 328
 329static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
 330				 const char *old_name)
 331{
 332	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
 333				  S_IFLNK);
 334}
 335
 336static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
 337			      struct dentry *new_dentry)
 338{
 339	struct aa_label *label;
 340	int error = 0;
 341
 342	if (!path_mediated_fs(old_dentry))
 343		return 0;
 344
 345	label = begin_current_label_crit_section();
 346	if (!unconfined(label))
 347		error = aa_path_link(label, old_dentry, new_dir, new_dentry);
 348	end_current_label_crit_section(label);
 349
 350	return error;
 351}
 352
 353static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
 354				const struct path *new_dir, struct dentry *new_dentry)
 355{
 356	struct aa_label *label;
 357	int error = 0;
 358
 359	if (!path_mediated_fs(old_dentry))
 360		return 0;
 361
 362	label = begin_current_label_crit_section();
 363	if (!unconfined(label)) {
 364		struct path old_path = { .mnt = old_dir->mnt,
 365					 .dentry = old_dentry };
 366		struct path new_path = { .mnt = new_dir->mnt,
 367					 .dentry = new_dentry };
 368		struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
 369					  d_backing_inode(old_dentry)->i_mode
 370		};
 371
 372		error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
 373				     MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
 374				     AA_MAY_SETATTR | AA_MAY_DELETE,
 375				     &cond);
 376		if (!error)
 377			error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
 378					     0, MAY_WRITE | AA_MAY_SETATTR |
 379					     AA_MAY_CREATE, &cond);
 380
 381	}
 382	end_current_label_crit_section(label);
 383
 384	return error;
 385}
 386
 387static int apparmor_path_chmod(const struct path *path, umode_t mode)
 
 388{
 389	return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
 
 
 
 390}
 391
 392static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
 393{
 394	return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
 
 
 
 
 
 
 
 395}
 396
 397static int apparmor_inode_getattr(const struct path *path)
 398{
 399	return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
 
 
 
 
 400}
 401
 402static int apparmor_file_open(struct file *file)
 403{
 404	struct aa_file_ctx *fctx = file_ctx(file);
 405	struct aa_label *label;
 406	int error = 0;
 407
 408	if (!path_mediated_fs(file->f_path.dentry))
 409		return 0;
 410
 411	/* If in exec, permission is handled by bprm hooks.
 412	 * Cache permissions granted by the previous exec check, with
 413	 * implicit read and executable mmap which are required to
 414	 * actually execute the image.
 415	 */
 416	if (current->in_execve) {
 417		fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
 418		return 0;
 419	}
 420
 421	label = aa_get_newest_cred_label(file->f_cred);
 422	if (!unconfined(label)) {
 423		struct inode *inode = file_inode(file);
 424		struct path_cond cond = { inode->i_uid, inode->i_mode };
 425
 426		error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
 427				     aa_map_file_to_perms(file), &cond);
 428		/* todo cache full allowed permissions set and state */
 429		fctx->allow = aa_map_file_to_perms(file);
 430	}
 431	aa_put_label(label);
 432
 433	return error;
 434}
 435
 436static int apparmor_file_alloc_security(struct file *file)
 437{
 438	struct aa_file_ctx *ctx = file_ctx(file);
 439	struct aa_label *label = begin_current_label_crit_section();
 
 
 
 440
 441	spin_lock_init(&ctx->lock);
 442	rcu_assign_pointer(ctx->label, aa_get_label(label));
 443	end_current_label_crit_section(label);
 444	return 0;
 445}
 446
 447static void apparmor_file_free_security(struct file *file)
 448{
 449	struct aa_file_ctx *ctx = file_ctx(file);
 450
 451	if (ctx)
 452		aa_put_label(rcu_access_pointer(ctx->label));
 453}
 454
 455static int common_file_perm(const char *op, struct file *file, u32 mask,
 456			    bool in_atomic)
 457{
 458	struct aa_label *label;
 
 459	int error = 0;
 460
 461	/* don't reaudit files closed during inheritance */
 462	if (file->f_path.dentry == aa_null.dentry)
 463		return -EACCES;
 
 
 464
 465	label = __begin_current_label_crit_section();
 466	error = aa_file_perm(op, label, file, mask, in_atomic);
 467	__end_current_label_crit_section(label);
 
 
 
 
 
 
 
 
 
 468
 469	return error;
 470}
 471
 472static int apparmor_file_receive(struct file *file)
 473{
 474	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
 475				false);
 476}
 477
 478static int apparmor_file_permission(struct file *file, int mask)
 479{
 480	return common_file_perm(OP_FPERM, file, mask, false);
 481}
 482
 483static int apparmor_file_lock(struct file *file, unsigned int cmd)
 484{
 485	u32 mask = AA_MAY_LOCK;
 486
 487	if (cmd == F_WRLCK)
 488		mask |= MAY_WRITE;
 489
 490	return common_file_perm(OP_FLOCK, file, mask, false);
 491}
 492
 493static int common_mmap(const char *op, struct file *file, unsigned long prot,
 494		       unsigned long flags, bool in_atomic)
 495{
 
 496	int mask = 0;
 497
 498	if (!file || !file_ctx(file))
 499		return 0;
 500
 501	if (prot & PROT_READ)
 502		mask |= MAY_READ;
 503	/*
 504	 * Private mappings don't require write perms since they don't
 505	 * write back to the files
 506	 */
 507	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
 508		mask |= MAY_WRITE;
 509	if (prot & PROT_EXEC)
 510		mask |= AA_EXEC_MMAP;
 511
 512	return common_file_perm(op, file, mask, in_atomic);
 
 513}
 514
 515static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
 516			      unsigned long prot, unsigned long flags)
 
 517{
 518	return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
 
 
 
 
 
 
 
 519}
 520
 521static int apparmor_file_mprotect(struct vm_area_struct *vma,
 522				  unsigned long reqprot, unsigned long prot)
 523{
 524	return common_mmap(OP_FMPROT, vma->vm_file, prot,
 525			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
 526			   false);
 527}
 528
 529static int apparmor_sb_mount(const char *dev_name, const struct path *path,
 530			     const char *type, unsigned long flags, void *data)
 531{
 532	struct aa_label *label;
 533	int error = 0;
 534
 535	/* Discard magic */
 536	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
 537		flags &= ~MS_MGC_MSK;
 538
 539	flags &= ~AA_MS_IGNORE_MASK;
 540
 541	label = __begin_current_label_crit_section();
 542	if (!unconfined(label)) {
 543		if (flags & MS_REMOUNT)
 544			error = aa_remount(label, path, flags, data);
 545		else if (flags & MS_BIND)
 546			error = aa_bind_mount(label, path, dev_name, flags);
 547		else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
 548				  MS_UNBINDABLE))
 549			error = aa_mount_change_type(label, path, flags);
 550		else if (flags & MS_MOVE)
 551			error = aa_move_mount(label, path, dev_name);
 552		else
 553			error = aa_new_mount(label, dev_name, path, type,
 554					     flags, data);
 555	}
 556	__end_current_label_crit_section(label);
 557
 558	return error;
 559}
 560
 561static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
 562{
 563	struct aa_label *label;
 564	int error = 0;
 565
 566	label = __begin_current_label_crit_section();
 567	if (!unconfined(label))
 568		error = aa_umount(label, mnt, flags);
 569	__end_current_label_crit_section(label);
 570
 571	return error;
 572}
 573
 574static int apparmor_sb_pivotroot(const struct path *old_path,
 575				 const struct path *new_path)
 576{
 577	struct aa_label *label;
 578	int error = 0;
 579
 580	label = aa_get_current_label();
 581	if (!unconfined(label))
 582		error = aa_pivotroot(label, old_path, new_path);
 583	aa_put_label(label);
 584
 585	return error;
 586}
 587
 588static int apparmor_getprocattr(struct task_struct *task, char *name,
 589				char **value)
 590{
 591	int error = -ENOENT;
 
 592	/* released below */
 593	const struct cred *cred = get_task_cred(task);
 594	struct aa_task_ctx *ctx = task_ctx(current);
 595	struct aa_label *label = NULL;
 596
 597	if (strcmp(name, "current") == 0)
 598		label = aa_get_newest_label(cred_label(cred));
 599	else if (strcmp(name, "prev") == 0  && ctx->previous)
 600		label = aa_get_newest_label(ctx->previous);
 601	else if (strcmp(name, "exec") == 0 && ctx->onexec)
 602		label = aa_get_newest_label(ctx->onexec);
 
 
 
 603	else
 604		error = -EINVAL;
 605
 606	if (label)
 607		error = aa_getprocattr(label, value);
 608
 609	aa_put_label(label);
 610	put_cred(cred);
 611
 612	return error;
 613}
 614
 615static int apparmor_setprocattr(const char *name, void *value,
 616				size_t size)
 617{
 618	char *command, *largs = NULL, *args = value;
 619	size_t arg_size;
 620	int error;
 621	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
 622
 623	if (size == 0)
 624		return -EINVAL;
 625
 626	/* AppArmor requires that the buffer must be null terminated atm */
 
 
 627	if (args[size - 1] != '\0') {
 628		/* null terminate */
 629		largs = args = kmalloc(size + 1, GFP_KERNEL);
 630		if (!args)
 631			return -ENOMEM;
 632		memcpy(args, value, size);
 633		args[size] = '\0';
 634	}
 635
 636	error = -EINVAL;
 
 
 
 
 637	args = strim(args);
 638	command = strsep(&args, " ");
 639	if (!args)
 640		goto out;
 641	args = skip_spaces(args);
 642	if (!*args)
 643		goto out;
 644
 645	arg_size = size - (args - (largs ? largs : (char *) value));
 646	if (strcmp(name, "current") == 0) {
 647		if (strcmp(command, "changehat") == 0) {
 648			error = aa_setprocattr_changehat(args, arg_size,
 649							 AA_CHANGE_NOFLAGS);
 650		} else if (strcmp(command, "permhat") == 0) {
 651			error = aa_setprocattr_changehat(args, arg_size,
 652							 AA_CHANGE_TEST);
 653		} else if (strcmp(command, "changeprofile") == 0) {
 654			error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
 
 655		} else if (strcmp(command, "permprofile") == 0) {
 656			error = aa_change_profile(args, AA_CHANGE_TEST);
 657		} else if (strcmp(command, "stack") == 0) {
 658			error = aa_change_profile(args, AA_CHANGE_STACK);
 659		} else
 660			goto fail;
 
 
 
 
 
 
 
 
 
 661	} else if (strcmp(name, "exec") == 0) {
 662		if (strcmp(command, "exec") == 0)
 663			error = aa_change_profile(args, AA_CHANGE_ONEXEC);
 664		else if (strcmp(command, "stack") == 0)
 665			error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
 666							 AA_CHANGE_STACK));
 667		else
 668			goto fail;
 669	} else
 670		/* only support the "current" and "exec" process attributes */
 671		goto fail;
 672
 673	if (!error)
 674		error = size;
 675out:
 676	kfree(largs);
 677	return error;
 678
 679fail:
 680	aad(&sa)->label = begin_current_label_crit_section();
 681	aad(&sa)->info = name;
 682	aad(&sa)->error = error = -EINVAL;
 683	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
 684	end_current_label_crit_section(aad(&sa)->label);
 685	goto out;
 686}
 687
 688/**
 689 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
 690 * @bprm: binprm for the exec  (NOT NULL)
 691 */
 692static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
 693{
 694	struct aa_label *label = aa_current_raw_label();
 695	struct aa_label *new_label = cred_label(bprm->cred);
 696
 697	/* bail out if unconfined or not changing profile */
 698	if ((new_label->proxy == label->proxy) ||
 699	    (unconfined(new_label)))
 700		return;
 701
 702	aa_inherit_files(bprm->cred, current->files);
 703
 704	current->pdeath_signal = 0;
 705
 706	/* reset soft limits and set hard limits for the new label */
 707	__aa_transition_rlimits(label, new_label);
 708}
 709
 710/**
 711 * apparmor_bprm_committed_cred - do cleanup after new creds committed
 712 * @bprm: binprm for the exec  (NOT NULL)
 713 */
 714static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
 715{
 716	/* clear out temporary/transitional state from the context */
 717	aa_clear_task_ctx_trans(task_ctx(current));
 718
 719	return;
 720}
 721
 722static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
 723{
 724	struct aa_label *label = aa_get_task_label(p);
 725	*secid = label->secid;
 726	aa_put_label(label);
 727}
 728
 729static int apparmor_task_setrlimit(struct task_struct *task,
 730		unsigned int resource, struct rlimit *new_rlim)
 731{
 732	struct aa_label *label = __begin_current_label_crit_section();
 733	int error = 0;
 734
 735	if (!unconfined(label))
 736		error = aa_task_setrlimit(label, task, resource, new_rlim);
 737	__end_current_label_crit_section(label);
 738
 739	return error;
 740}
 741
 742static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
 743			      int sig, const struct cred *cred)
 744{
 745	struct aa_label *cl, *tl;
 746	int error;
 747
 748	if (cred) {
 749		/*
 750		 * Dealing with USB IO specific behavior
 751		 */
 752		cl = aa_get_newest_cred_label(cred);
 753		tl = aa_get_task_label(target);
 754		error = aa_may_signal(cl, tl, sig);
 755		aa_put_label(cl);
 756		aa_put_label(tl);
 757		return error;
 758	}
 759
 760	cl = __begin_current_label_crit_section();
 761	tl = aa_get_task_label(target);
 762	error = aa_may_signal(cl, tl, sig);
 763	aa_put_label(tl);
 764	__end_current_label_crit_section(cl);
 765
 766	return error;
 767}
 768
 769/**
 770 * apparmor_sk_alloc_security - allocate and attach the sk_security field
 771 */
 772static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
 773{
 774	struct aa_sk_ctx *ctx;
 775
 776	ctx = kzalloc(sizeof(*ctx), flags);
 777	if (!ctx)
 778		return -ENOMEM;
 779
 780	SK_CTX(sk) = ctx;
 781
 782	return 0;
 783}
 784
 785/**
 786 * apparmor_sk_free_security - free the sk_security field
 787 */
 788static void apparmor_sk_free_security(struct sock *sk)
 789{
 790	struct aa_sk_ctx *ctx = SK_CTX(sk);
 791
 792	SK_CTX(sk) = NULL;
 793	aa_put_label(ctx->label);
 794	aa_put_label(ctx->peer);
 795	kfree(ctx);
 796}
 797
 798/**
 799 * apparmor_clone_security - clone the sk_security field
 800 */
 801static void apparmor_sk_clone_security(const struct sock *sk,
 802				       struct sock *newsk)
 803{
 804	struct aa_sk_ctx *ctx = SK_CTX(sk);
 805	struct aa_sk_ctx *new = SK_CTX(newsk);
 806
 807	if (new->label)
 808		aa_put_label(new->label);
 809	new->label = aa_get_label(ctx->label);
 810
 811	if (new->peer)
 812		aa_put_label(new->peer);
 813	new->peer = aa_get_label(ctx->peer);
 814}
 815
 816/**
 817 * apparmor_socket_create - check perms before creating a new socket
 818 */
 819static int apparmor_socket_create(int family, int type, int protocol, int kern)
 820{
 821	struct aa_label *label;
 822	int error = 0;
 823
 824	AA_BUG(in_interrupt());
 825
 826	label = begin_current_label_crit_section();
 827	if (!(kern || unconfined(label)))
 828		error = af_select(family,
 829				  create_perm(label, family, type, protocol),
 830				  aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
 831					     family, type, protocol));
 832	end_current_label_crit_section(label);
 833
 834	return error;
 835}
 836
 837/**
 838 * apparmor_socket_post_create - setup the per-socket security struct
 839 *
 840 * Note:
 841 * -   kernel sockets currently labeled unconfined but we may want to
 842 *     move to a special kernel label
 843 * -   socket may not have sk here if created with sock_create_lite or
 844 *     sock_alloc. These should be accept cases which will be handled in
 845 *     sock_graft.
 846 */
 847static int apparmor_socket_post_create(struct socket *sock, int family,
 848				       int type, int protocol, int kern)
 849{
 850	struct aa_label *label;
 851
 852	if (kern) {
 853		struct aa_ns *ns = aa_get_current_ns();
 854
 855		label = aa_get_label(ns_unconfined(ns));
 856		aa_put_ns(ns);
 857	} else
 858		label = aa_get_current_label();
 859
 860	if (sock->sk) {
 861		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
 862
 863		aa_put_label(ctx->label);
 864		ctx->label = aa_get_label(label);
 865	}
 866	aa_put_label(label);
 867
 868	return 0;
 869}
 870
 871/**
 872 * apparmor_socket_bind - check perms before bind addr to socket
 873 */
 874static int apparmor_socket_bind(struct socket *sock,
 875				struct sockaddr *address, int addrlen)
 876{
 877	AA_BUG(!sock);
 878	AA_BUG(!sock->sk);
 879	AA_BUG(!address);
 880	AA_BUG(in_interrupt());
 881
 882	return af_select(sock->sk->sk_family,
 883			 bind_perm(sock, address, addrlen),
 884			 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
 885}
 886
 887/**
 888 * apparmor_socket_connect - check perms before connecting @sock to @address
 889 */
 890static int apparmor_socket_connect(struct socket *sock,
 891				   struct sockaddr *address, int addrlen)
 892{
 893	AA_BUG(!sock);
 894	AA_BUG(!sock->sk);
 895	AA_BUG(!address);
 896	AA_BUG(in_interrupt());
 897
 898	return af_select(sock->sk->sk_family,
 899			 connect_perm(sock, address, addrlen),
 900			 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
 901}
 902
 903/**
 904 * apparmor_socket_list - check perms before allowing listen
 905 */
 906static int apparmor_socket_listen(struct socket *sock, int backlog)
 907{
 908	AA_BUG(!sock);
 909	AA_BUG(!sock->sk);
 910	AA_BUG(in_interrupt());
 911
 912	return af_select(sock->sk->sk_family,
 913			 listen_perm(sock, backlog),
 914			 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
 915}
 916
 917/**
 918 * apparmor_socket_accept - check perms before accepting a new connection.
 919 *
 920 * Note: while @newsock is created and has some information, the accept
 921 *       has not been done.
 922 */
 923static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
 924{
 925	AA_BUG(!sock);
 926	AA_BUG(!sock->sk);
 927	AA_BUG(!newsock);
 928	AA_BUG(in_interrupt());
 929
 930	return af_select(sock->sk->sk_family,
 931			 accept_perm(sock, newsock),
 932			 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
 933}
 934
 935static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
 936			    struct msghdr *msg, int size)
 937{
 938	AA_BUG(!sock);
 939	AA_BUG(!sock->sk);
 940	AA_BUG(!msg);
 941	AA_BUG(in_interrupt());
 942
 943	return af_select(sock->sk->sk_family,
 944			 msg_perm(op, request, sock, msg, size),
 945			 aa_sk_perm(op, request, sock->sk));
 946}
 947
 948/**
 949 * apparmor_socket_sendmsg - check perms before sending msg to another socket
 950 */
 951static int apparmor_socket_sendmsg(struct socket *sock,
 952				   struct msghdr *msg, int size)
 953{
 954	return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
 955}
 
 
 
 
 956
 957/**
 958 * apparmor_socket_recvmsg - check perms before receiving a message
 959 */
 960static int apparmor_socket_recvmsg(struct socket *sock,
 961				   struct msghdr *msg, int size, int flags)
 962{
 963	return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
 964}
 965
 966/* revaliation, get/set attr, shutdown */
 967static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
 968{
 969	AA_BUG(!sock);
 970	AA_BUG(!sock->sk);
 971	AA_BUG(in_interrupt());
 972
 973	return af_select(sock->sk->sk_family,
 974			 sock_perm(op, request, sock),
 975			 aa_sk_perm(op, request, sock->sk));
 976}
 977
 978/**
 979 * apparmor_socket_getsockname - check perms before getting the local address
 980 */
 981static int apparmor_socket_getsockname(struct socket *sock)
 982{
 983	return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
 984}
 985
 986/**
 987 * apparmor_socket_getpeername - check perms before getting remote address
 988 */
 989static int apparmor_socket_getpeername(struct socket *sock)
 990{
 991	return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
 992}
 993
 994/* revaliation, get/set attr, opt */
 995static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
 996			    int level, int optname)
 997{
 998	AA_BUG(!sock);
 999	AA_BUG(!sock->sk);
1000	AA_BUG(in_interrupt());
1001
1002	return af_select(sock->sk->sk_family,
1003			 opt_perm(op, request, sock, level, optname),
1004			 aa_sk_perm(op, request, sock->sk));
1005}
1006
1007/**
1008 * apparmor_getsockopt - check perms before getting socket options
1009 */
1010static int apparmor_socket_getsockopt(struct socket *sock, int level,
1011				      int optname)
1012{
1013	return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1014				level, optname);
1015}
1016
1017/**
1018 * apparmor_setsockopt - check perms before setting socket options
1019 */
1020static int apparmor_socket_setsockopt(struct socket *sock, int level,
1021				      int optname)
1022{
1023	return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1024				level, optname);
1025}
1026
1027/**
1028 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1029 */
1030static int apparmor_socket_shutdown(struct socket *sock, int how)
1031{
1032	return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1033}
1034
1035#ifdef CONFIG_NETWORK_SECMARK
1036/**
1037 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1038 *
1039 * Note: can not sleep may be called with locks held
1040 *
1041 * dont want protocol specific in __skb_recv_datagram()
1042 * to deny an incoming connection  socket_sock_rcv_skb()
1043 */
1044static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1045{
1046	struct aa_sk_ctx *ctx = SK_CTX(sk);
1047
1048	if (!skb->secmark)
1049		return 0;
1050
1051	return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1052				      skb->secmark, sk);
1053}
1054#endif
1055
1056
1057static struct aa_label *sk_peer_label(struct sock *sk)
1058{
1059	struct aa_sk_ctx *ctx = SK_CTX(sk);
1060
1061	if (ctx->peer)
1062		return ctx->peer;
1063
1064	return ERR_PTR(-ENOPROTOOPT);
1065}
1066
1067/**
1068 * apparmor_socket_getpeersec_stream - get security context of peer
1069 *
1070 * Note: for tcp only valid if using ipsec or cipso on lan
1071 */
1072static int apparmor_socket_getpeersec_stream(struct socket *sock,
1073					     char __user *optval,
1074					     int __user *optlen,
1075					     unsigned int len)
1076{
1077	char *name;
1078	int slen, error = 0;
1079	struct aa_label *label;
1080	struct aa_label *peer;
1081
1082	label = begin_current_label_crit_section();
1083	peer = sk_peer_label(sock->sk);
1084	if (IS_ERR(peer)) {
1085		error = PTR_ERR(peer);
1086		goto done;
1087	}
1088	slen = aa_label_asxprint(&name, labels_ns(label), peer,
1089				 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1090				 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1091	/* don't include terminating \0 in slen, it breaks some apps */
1092	if (slen < 0) {
1093		error = -ENOMEM;
1094	} else {
1095		if (slen > len) {
1096			error = -ERANGE;
1097		} else if (copy_to_user(optval, name, slen)) {
1098			error = -EFAULT;
1099			goto out;
1100		}
1101		if (put_user(slen, optlen))
1102			error = -EFAULT;
1103out:
1104		kfree(name);
1105
1106	}
1107
1108done:
1109	end_current_label_crit_section(label);
1110
1111	return error;
1112}
1113
1114/**
1115 * apparmor_socket_getpeersec_dgram - get security label of packet
1116 * @sock: the peer socket
1117 * @skb: packet data
1118 * @secid: pointer to where to put the secid of the packet
1119 *
1120 * Sets the netlabel socket state on sk from parent
1121 */
1122static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1123					    struct sk_buff *skb, u32 *secid)
1124
1125{
1126	/* TODO: requires secid support */
1127	return -ENOPROTOOPT;
1128}
1129
1130/**
1131 * apparmor_sock_graft - Initialize newly created socket
1132 * @sk: child sock
1133 * @parent: parent socket
1134 *
1135 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1136 *       just set sk security information off of current creating process label
1137 *       Labeling of sk for accept case - probably should be sock based
1138 *       instead of task, because of the case where an implicitly labeled
1139 *       socket is shared by different tasks.
1140 */
1141static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1142{
1143	struct aa_sk_ctx *ctx = SK_CTX(sk);
1144
1145	if (!ctx->label)
1146		ctx->label = aa_get_current_label();
1147}
1148
1149#ifdef CONFIG_NETWORK_SECMARK
1150static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
1151				      struct request_sock *req)
1152{
1153	struct aa_sk_ctx *ctx = SK_CTX(sk);
1154
1155	if (!skb->secmark)
1156		return 0;
1157
1158	return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1159				      skb->secmark, sk);
1160}
1161#endif
1162
1163/*
1164 * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
1165 */
1166struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
1167	.lbs_cred = sizeof(struct aa_task_ctx *),
1168	.lbs_file = sizeof(struct aa_file_ctx),
1169	.lbs_task = sizeof(struct aa_task_ctx),
1170};
1171
1172static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1173	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1174	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1175	LSM_HOOK_INIT(capget, apparmor_capget),
1176	LSM_HOOK_INIT(capable, apparmor_capable),
1177
1178	LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1179	LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1180	LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1181
1182	LSM_HOOK_INIT(path_link, apparmor_path_link),
1183	LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1184	LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1185	LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1186	LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1187	LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1188	LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1189	LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1190	LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1191	LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1192	LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1193
1194	LSM_HOOK_INIT(file_open, apparmor_file_open),
1195	LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1196	LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1197	LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1198	LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1199	LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1200	LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1201	LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1202
1203	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1204	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1205
1206	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1207	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1208	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1209
1210	LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1211	LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1212	LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1213	LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1214	LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1215	LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1216	LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1217	LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1218	LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1219	LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1220	LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1221	LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1222	LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1223#ifdef CONFIG_NETWORK_SECMARK
1224	LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1225#endif
1226	LSM_HOOK_INIT(socket_getpeersec_stream,
1227		      apparmor_socket_getpeersec_stream),
1228	LSM_HOOK_INIT(socket_getpeersec_dgram,
1229		      apparmor_socket_getpeersec_dgram),
1230	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1231#ifdef CONFIG_NETWORK_SECMARK
1232	LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1233#endif
1234
1235	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1236	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1237	LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1238	LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1239
1240	LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1241	LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1242	LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1243
1244	LSM_HOOK_INIT(task_free, apparmor_task_free),
1245	LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1246	LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
1247	LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1248	LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1249
1250#ifdef CONFIG_AUDIT
1251	LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1252	LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1253	LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1254	LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1255#endif
1256
1257	LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1258	LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1259	LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1260};
1261
1262/*
1263 * AppArmor sysfs module parameters
1264 */
1265
1266static int param_set_aabool(const char *val, const struct kernel_param *kp);
1267static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1268#define param_check_aabool param_check_bool
1269static const struct kernel_param_ops param_ops_aabool = {
1270	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1271	.set = param_set_aabool,
1272	.get = param_get_aabool
1273};
1274
1275static int param_set_aauint(const char *val, const struct kernel_param *kp);
1276static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1277#define param_check_aauint param_check_uint
1278static const struct kernel_param_ops param_ops_aauint = {
1279	.set = param_set_aauint,
1280	.get = param_get_aauint
1281};
1282
1283static int param_set_aacompressionlevel(const char *val,
1284					const struct kernel_param *kp);
1285static int param_get_aacompressionlevel(char *buffer,
1286					const struct kernel_param *kp);
1287#define param_check_aacompressionlevel param_check_int
1288static const struct kernel_param_ops param_ops_aacompressionlevel = {
1289	.set = param_set_aacompressionlevel,
1290	.get = param_get_aacompressionlevel
1291};
1292
1293static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1294static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1295#define param_check_aalockpolicy param_check_bool
1296static const struct kernel_param_ops param_ops_aalockpolicy = {
1297	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1298	.set = param_set_aalockpolicy,
1299	.get = param_get_aalockpolicy
1300};
1301
1302static int param_set_audit(const char *val, const struct kernel_param *kp);
1303static int param_get_audit(char *buffer, const struct kernel_param *kp);
1304
1305static int param_set_mode(const char *val, const struct kernel_param *kp);
1306static int param_get_mode(char *buffer, const struct kernel_param *kp);
1307
1308/* Flag values, also controllable via /sys/module/apparmor/parameters
1309 * We define special types as we want to do additional mediation.
1310 */
1311
1312/* AppArmor global enforcement switch - complain, enforce, kill */
1313enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1314module_param_call(mode, param_set_mode, param_get_mode,
1315		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1316
1317/* whether policy verification hashing is enabled */
1318bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1319#ifdef CONFIG_SECURITY_APPARMOR_HASH
1320module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1321#endif
1322
1323/* policy loaddata compression level */
1324int aa_g_rawdata_compression_level = Z_DEFAULT_COMPRESSION;
1325module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1326		   aacompressionlevel, 0400);
1327
1328/* Debug mode */
1329bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1330module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1331
1332/* Audit mode */
1333enum audit_mode aa_g_audit;
1334module_param_call(audit, param_set_audit, param_get_audit,
1335		  &aa_g_audit, S_IRUSR | S_IWUSR);
1336
1337/* Determines if audit header is included in audited messages.  This
1338 * provides more context if the audit daemon is not running
1339 */
1340bool aa_g_audit_header = true;
1341module_param_named(audit_header, aa_g_audit_header, aabool,
1342		   S_IRUSR | S_IWUSR);
1343
1344/* lock out loading/removal of policy
1345 * TODO: add in at boot loading of policy, which is the only way to
1346 *       load policy, if lock_policy is set
1347 */
1348bool aa_g_lock_policy;
1349module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1350		   S_IRUSR | S_IWUSR);
1351
1352/* Syscall logging mode */
1353bool aa_g_logsyscall;
1354module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1355
1356/* Maximum pathname length before accesses will start getting rejected */
1357unsigned int aa_g_path_max = 2 * PATH_MAX;
1358module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1359
1360/* Determines how paranoid loading of policy is and how much verification
1361 * on the loaded policy is done.
1362 * DEPRECATED: read only as strict checking of load is always done now
1363 * that none root users (user namespaces) can load policy.
1364 */
1365bool aa_g_paranoid_load = true;
1366module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
 
1367
1368static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1369static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1370#define param_check_aaintbool param_check_int
1371static const struct kernel_param_ops param_ops_aaintbool = {
1372	.set = param_set_aaintbool,
1373	.get = param_get_aaintbool
1374};
1375/* Boot time disable flag */
1376static int apparmor_enabled __lsm_ro_after_init = 1;
1377module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1378
1379static int __init apparmor_enabled_setup(char *str)
1380{
1381	unsigned long enabled;
1382	int error = kstrtoul(str, 0, &enabled);
1383	if (!error)
1384		apparmor_enabled = enabled ? 1 : 0;
1385	return 1;
1386}
1387
1388__setup("apparmor=", apparmor_enabled_setup);
1389
1390/* set global flag turning off the ability to load policy */
1391static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1392{
1393	if (!apparmor_enabled)
1394		return -EINVAL;
1395	if (apparmor_initialized && !policy_admin_capable(NULL))
1396		return -EPERM;
 
 
1397	return param_set_bool(val, kp);
1398}
1399
1400static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1401{
1402	if (!apparmor_enabled)
1403		return -EINVAL;
1404	if (apparmor_initialized && !policy_view_capable(NULL))
1405		return -EPERM;
1406	return param_get_bool(buffer, kp);
1407}
1408
1409static int param_set_aabool(const char *val, const struct kernel_param *kp)
1410{
1411	if (!apparmor_enabled)
1412		return -EINVAL;
1413	if (apparmor_initialized && !policy_admin_capable(NULL))
1414		return -EPERM;
1415	return param_set_bool(val, kp);
1416}
1417
1418static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1419{
1420	if (!apparmor_enabled)
1421		return -EINVAL;
1422	if (apparmor_initialized && !policy_view_capable(NULL))
1423		return -EPERM;
1424	return param_get_bool(buffer, kp);
1425}
1426
1427static int param_set_aauint(const char *val, const struct kernel_param *kp)
1428{
1429	int error;
1430
1431	if (!apparmor_enabled)
1432		return -EINVAL;
1433	/* file is ro but enforce 2nd line check */
1434	if (apparmor_initialized)
1435		return -EPERM;
1436
1437	error = param_set_uint(val, kp);
1438	aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
1439	pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1440
1441	return error;
1442}
1443
1444static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1445{
1446	if (!apparmor_enabled)
1447		return -EINVAL;
1448	if (apparmor_initialized && !policy_view_capable(NULL))
1449		return -EPERM;
1450	return param_get_uint(buffer, kp);
1451}
1452
1453/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1454static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1455{
1456	struct kernel_param kp_local;
1457	bool value;
1458	int error;
1459
1460	if (apparmor_initialized)
1461		return -EPERM;
1462
1463	/* Create local copy, with arg pointing to bool type. */
1464	value = !!*((int *)kp->arg);
1465	memcpy(&kp_local, kp, sizeof(kp_local));
1466	kp_local.arg = &value;
1467
1468	error = param_set_bool(val, &kp_local);
1469	if (!error)
1470		*((int *)kp->arg) = *((bool *)kp_local.arg);
1471	return error;
1472}
1473
1474/*
1475 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1476 * 1/0, this converts the "int that is actually bool" back to bool for
1477 * display in the /sys filesystem, while keeping it "int" for the LSM
1478 * infrastructure.
1479 */
1480static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1481{
1482	struct kernel_param kp_local;
1483	bool value;
1484
1485	/* Create local copy, with arg pointing to bool type. */
1486	value = !!*((int *)kp->arg);
1487	memcpy(&kp_local, kp, sizeof(kp_local));
1488	kp_local.arg = &value;
1489
1490	return param_get_bool(buffer, &kp_local);
1491}
1492
1493static int param_set_aacompressionlevel(const char *val,
1494					const struct kernel_param *kp)
1495{
1496	int error;
1497
1498	if (!apparmor_enabled)
1499		return -EINVAL;
1500	if (apparmor_initialized)
1501		return -EPERM;
1502
1503	error = param_set_int(val, kp);
1504
1505	aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
1506					       Z_NO_COMPRESSION,
1507					       Z_BEST_COMPRESSION);
1508	pr_info("AppArmor: policy rawdata compression level set to %u\n",
1509		aa_g_rawdata_compression_level);
1510
1511	return error;
1512}
1513
1514static int param_get_aacompressionlevel(char *buffer,
1515					const struct kernel_param *kp)
1516{
1517	if (!apparmor_enabled)
1518		return -EINVAL;
1519	if (apparmor_initialized && !policy_view_capable(NULL))
1520		return -EPERM;
1521	return param_get_int(buffer, kp);
1522}
1523
1524static int param_get_audit(char *buffer, const struct kernel_param *kp)
1525{
1526	if (!apparmor_enabled)
1527		return -EINVAL;
1528	if (apparmor_initialized && !policy_view_capable(NULL))
1529		return -EPERM;
1530	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1531}
1532
1533static int param_set_audit(const char *val, const struct kernel_param *kp)
1534{
1535	int i;
1536
1537	if (!apparmor_enabled)
1538		return -EINVAL;
1539	if (!val)
1540		return -EINVAL;
1541	if (apparmor_initialized && !policy_admin_capable(NULL))
1542		return -EPERM;
1543
1544	i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1545	if (i < 0)
1546		return -EINVAL;
 
 
 
1547
1548	aa_g_audit = i;
1549	return 0;
1550}
1551
1552static int param_get_mode(char *buffer, const struct kernel_param *kp)
1553{
 
 
 
1554	if (!apparmor_enabled)
1555		return -EINVAL;
1556	if (apparmor_initialized && !policy_view_capable(NULL))
1557		return -EPERM;
1558
1559	return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1560}
1561
1562static int param_set_mode(const char *val, const struct kernel_param *kp)
1563{
1564	int i;
 
 
1565
1566	if (!apparmor_enabled)
1567		return -EINVAL;
 
1568	if (!val)
1569		return -EINVAL;
1570	if (apparmor_initialized && !policy_admin_capable(NULL))
1571		return -EPERM;
1572
1573	i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1574			 val);
1575	if (i < 0)
1576		return -EINVAL;
1577
1578	aa_g_profile_mode = i;
1579	return 0;
1580}
1581
1582char *aa_get_buffer(bool in_atomic)
1583{
1584	union aa_buffer *aa_buf;
1585	bool try_again = true;
1586	gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1587
1588retry:
1589	spin_lock(&aa_buffers_lock);
1590	if (buffer_count > reserve_count ||
1591	    (in_atomic && !list_empty(&aa_global_buffers))) {
1592		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1593					  list);
1594		list_del(&aa_buf->list);
1595		buffer_count--;
1596		spin_unlock(&aa_buffers_lock);
1597		return &aa_buf->buffer[0];
1598	}
1599	if (in_atomic) {
1600		/*
1601		 * out of reserve buffers and in atomic context so increase
1602		 * how many buffers to keep in reserve
1603		 */
1604		reserve_count++;
1605		flags = GFP_ATOMIC;
1606	}
1607	spin_unlock(&aa_buffers_lock);
1608
1609	if (!in_atomic)
1610		might_sleep();
1611	aa_buf = kmalloc(aa_g_path_max, flags);
1612	if (!aa_buf) {
1613		if (try_again) {
1614			try_again = false;
1615			goto retry;
1616		}
1617		pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
1618		return NULL;
1619	}
1620	return &aa_buf->buffer[0];
1621}
1622
1623void aa_put_buffer(char *buf)
1624{
1625	union aa_buffer *aa_buf;
1626
1627	if (!buf)
1628		return;
1629	aa_buf = container_of(buf, union aa_buffer, buffer[0]);
1630
1631	spin_lock(&aa_buffers_lock);
1632	list_add(&aa_buf->list, &aa_global_buffers);
1633	buffer_count++;
1634	spin_unlock(&aa_buffers_lock);
1635}
1636
1637/*
1638 * AppArmor init functions
1639 */
1640
1641/**
1642 * set_init_ctx - set a task context and profile on the first task.
1643 *
1644 * TODO: allow setting an alternate profile than unconfined
1645 */
1646static int __init set_init_ctx(void)
1647{
1648	struct cred *cred = (__force struct cred *)current->real_cred;
 
1649
1650	set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1651
1652	return 0;
1653}
1654
1655static void destroy_buffers(void)
1656{
1657	union aa_buffer *aa_buf;
1658
1659	spin_lock(&aa_buffers_lock);
1660	while (!list_empty(&aa_global_buffers)) {
1661		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1662					 list);
1663		list_del(&aa_buf->list);
1664		spin_unlock(&aa_buffers_lock);
1665		kfree(aa_buf);
1666		spin_lock(&aa_buffers_lock);
1667	}
1668	spin_unlock(&aa_buffers_lock);
1669}
1670
1671static int __init alloc_buffers(void)
1672{
1673	union aa_buffer *aa_buf;
1674	int i, num;
1675
1676	/*
1677	 * A function may require two buffers at once. Usually the buffers are
1678	 * used for a short period of time and are shared. On UP kernel buffers
1679	 * two should be enough, with more CPUs it is possible that more
1680	 * buffers will be used simultaneously. The preallocated pool may grow.
1681	 * This preallocation has also the side-effect that AppArmor will be
1682	 * disabled early at boot if aa_g_path_max is extremly high.
1683	 */
1684	if (num_online_cpus() > 1)
1685		num = 4 + RESERVE_COUNT;
1686	else
1687		num = 2 + RESERVE_COUNT;
1688
1689	for (i = 0; i < num; i++) {
1690
1691		aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
1692				 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1693		if (!aa_buf) {
1694			destroy_buffers();
1695			return -ENOMEM;
1696		}
1697		aa_put_buffer(&aa_buf->buffer[0]);
1698	}
1699	return 0;
1700}
1701
1702#ifdef CONFIG_SYSCTL
1703static int apparmor_dointvec(struct ctl_table *table, int write,
1704			     void *buffer, size_t *lenp, loff_t *ppos)
1705{
1706	if (!policy_admin_capable(NULL))
1707		return -EPERM;
1708	if (!apparmor_enabled)
1709		return -EINVAL;
1710
1711	return proc_dointvec(table, write, buffer, lenp, ppos);
1712}
1713
1714static struct ctl_path apparmor_sysctl_path[] = {
1715	{ .procname = "kernel", },
1716	{ }
1717};
1718
1719static struct ctl_table apparmor_sysctl_table[] = {
1720	{
1721		.procname       = "unprivileged_userns_apparmor_policy",
1722		.data           = &unprivileged_userns_apparmor_policy,
1723		.maxlen         = sizeof(int),
1724		.mode           = 0600,
1725		.proc_handler   = apparmor_dointvec,
1726	},
1727	{ }
1728};
1729
1730static int __init apparmor_init_sysctl(void)
1731{
1732	return register_sysctl_paths(apparmor_sysctl_path,
1733				     apparmor_sysctl_table) ? 0 : -ENOMEM;
1734}
1735#else
1736static inline int apparmor_init_sysctl(void)
1737{
1738	return 0;
1739}
1740#endif /* CONFIG_SYSCTL */
1741
1742#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1743static unsigned int apparmor_ip_postroute(void *priv,
1744					  struct sk_buff *skb,
1745					  const struct nf_hook_state *state)
1746{
1747	struct aa_sk_ctx *ctx;
1748	struct sock *sk;
1749
1750	if (!skb->secmark)
1751		return NF_ACCEPT;
1752
1753	sk = skb_to_full_sk(skb);
1754	if (sk == NULL)
1755		return NF_ACCEPT;
1756
1757	ctx = SK_CTX(sk);
1758	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
1759				    skb->secmark, sk))
1760		return NF_ACCEPT;
1761
1762	return NF_DROP_ERR(-ECONNREFUSED);
1763
1764}
1765
1766static unsigned int apparmor_ipv4_postroute(void *priv,
1767					    struct sk_buff *skb,
1768					    const struct nf_hook_state *state)
1769{
1770	return apparmor_ip_postroute(priv, skb, state);
1771}
1772
1773#if IS_ENABLED(CONFIG_IPV6)
1774static unsigned int apparmor_ipv6_postroute(void *priv,
1775					    struct sk_buff *skb,
1776					    const struct nf_hook_state *state)
1777{
1778	return apparmor_ip_postroute(priv, skb, state);
1779}
1780#endif
1781
1782static const struct nf_hook_ops apparmor_nf_ops[] = {
1783	{
1784		.hook =         apparmor_ipv4_postroute,
1785		.pf =           NFPROTO_IPV4,
1786		.hooknum =      NF_INET_POST_ROUTING,
1787		.priority =     NF_IP_PRI_SELINUX_FIRST,
1788	},
1789#if IS_ENABLED(CONFIG_IPV6)
1790	{
1791		.hook =         apparmor_ipv6_postroute,
1792		.pf =           NFPROTO_IPV6,
1793		.hooknum =      NF_INET_POST_ROUTING,
1794		.priority =     NF_IP6_PRI_SELINUX_FIRST,
1795	},
1796#endif
1797};
1798
1799static int __net_init apparmor_nf_register(struct net *net)
1800{
1801	int ret;
1802
1803	ret = nf_register_net_hooks(net, apparmor_nf_ops,
1804				    ARRAY_SIZE(apparmor_nf_ops));
1805	return ret;
1806}
1807
1808static void __net_exit apparmor_nf_unregister(struct net *net)
1809{
1810	nf_unregister_net_hooks(net, apparmor_nf_ops,
1811				ARRAY_SIZE(apparmor_nf_ops));
1812}
1813
1814static struct pernet_operations apparmor_net_ops = {
1815	.init = apparmor_nf_register,
1816	.exit = apparmor_nf_unregister,
1817};
1818
1819static int __init apparmor_nf_ip_init(void)
1820{
1821	int err;
1822
1823	if (!apparmor_enabled)
1824		return 0;
1825
1826	err = register_pernet_subsys(&apparmor_net_ops);
1827	if (err)
1828		panic("Apparmor: register_pernet_subsys: error %d\n", err);
1829
1830	return 0;
1831}
1832__initcall(apparmor_nf_ip_init);
1833#endif
1834
1835static int __init apparmor_init(void)
1836{
1837	int error;
1838
1839	aa_secids_init();
1840
1841	error = aa_setup_dfa_engine();
1842	if (error) {
1843		AA_ERROR("Unable to setup dfa engine\n");
1844		goto alloc_out;
1845	}
1846
1847	error = aa_alloc_root_ns();
1848	if (error) {
1849		AA_ERROR("Unable to allocate default profile namespace\n");
1850		goto alloc_out;
1851	}
1852
1853	error = apparmor_init_sysctl();
1854	if (error) {
1855		AA_ERROR("Unable to register sysctls\n");
1856		goto alloc_out;
1857
1858	}
1859
1860	error = alloc_buffers();
1861	if (error) {
1862		AA_ERROR("Unable to allocate work buffers\n");
1863		goto alloc_out;
1864	}
1865
1866	error = set_init_ctx();
1867	if (error) {
1868		AA_ERROR("Failed to set context on init task\n");
1869		aa_free_root_ns();
1870		goto buffers_out;
1871	}
1872	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1873				"apparmor");
1874
1875	/* Report that AppArmor successfully initialized */
1876	apparmor_initialized = 1;
1877	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1878		aa_info_message("AppArmor initialized: complain mode enabled");
1879	else if (aa_g_profile_mode == APPARMOR_KILL)
1880		aa_info_message("AppArmor initialized: kill mode enabled");
1881	else
1882		aa_info_message("AppArmor initialized");
1883
1884	return error;
1885
1886buffers_out:
1887	destroy_buffers();
 
 
 
 
1888alloc_out:
1889	aa_destroy_aafs();
1890	aa_teardown_dfa_engine();
1891
1892	apparmor_enabled = false;
1893	return error;
1894}
1895
1896DEFINE_LSM(apparmor) = {
1897	.name = "apparmor",
1898	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
1899	.enabled = &apparmor_enabled,
1900	.blobs = &apparmor_blob_sizes,
1901	.init = apparmor_init,
1902};