summaryrefslogblamecommitdiffstats
path: root/security/apparmor/lsm.c
blob: 8b8b70620bbe753e35db3fe5e679334dab8ebb83 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128













                                                                 
                            








                              
                                 





                               
                         

                         
                        
                         
                          
                           
                              
                             
                          
                          

                                                      
                         
 


                                              




                     
                            


                                                 

                                       






                                                                  
                                



                 
                                                                



                                                                          
                                                               







                                                                            
                                                               

 














                                                                
                                                
                             
 
                 




                                                                  





                                                    

                                                                     



                                               



                                                              









                                                               





                                                                               
                               



                                   
                                               
 



                                                       











                                                                        

                          
                            



                 

                                                                               
 
                               

                      

                                               
                                                      
                            
 











                                                                   
                                                                         

                                              
                               

                      

                                                     
                                                                     
                                                




                     
                                                                 
                               
                                      
                                    


                                                            
                                                                              
 


                                                                       
 



                                                  


   
                                                                              
                               

                                            
                                    
                                                                 


                                                            


                                                                         
 
                                                                 
 
                                                  










                                                                     
                                                                 

                                                          
                                                      

                                    
                                                

















                                                                             
                                                                     
                                                                            


                                                          
                                           




                                                                    
                                                                              



                                                                     
                                                                             
                                            




                                                                       
                                                                             



                                                                    
                                                                             
                                                              



                                                                              
                                                          
 
                                                                            

 
                                                                               





                                                                         
                                                                                    

                                                        
                               

                      
                                          

                         

                                                   
                                                                             
                                              
 


                     

                                                                                      
 
                               

                      
                                          

                         

                                                   



                                                                

                                                                             

                  
                                                                        

                                                                            

                                            
                                                                              
                                                                            


                                                                   
                                              
 


                     
                                                                     
 
                                                              

 
                                                                               
 
                                                              

 
                                                          
 
                                                                  

 
                                                
 

                                                  

                      
                                                   







                                                                     
                                                                 


                         
                                                       
                                 
                                                       

                                                                        
                                                                      

                                                                        
                                                         
         
                            





                                                          

                      
                                                  
                                                                    
                                                                

                                
                                              
 
                     



                                                          
                                         

 
                                                                        
 
                               

                      



                                                           
                                                     
                                                    
                                                



                     




                                                                               














                                                                  
                                                                             

                                           

                     
                                     












                                                                      


                                                

                                                                       
 









                                                                            


























































                                                                               



                                                                     

                                                      
                                                    
                                      

                                         
                                                              
                                                             
                                                           
                                                          
                                                         


                                
                  
                                                     
 
                            




                       

                                                              
 
                                                    

                        
                                                                   


                               
 










                                                                           


                                     
                         

                                 
                         
 
                                                                    


                                                                        
                                                                            

                                                                        
                                                                         
                                                                   
                                                                           
                                                                 
                                                                        

                                                                         

                                  
                                               
                                                 
                                                                          


                                                                           


                                  
                                                                              
                          
 

                             

                     
                     

     
                                                             

                                          
                                                       
                                                        
                 

 





                                                                           
                                                        
                                                            

                                                            

                                                 

                       

                                                     

                                   
                                                                     
                                                  







                                                                      
                                                                     
                                                   
 


               






                                                                     

                                                               
 
                                                                      

                      
                               
                                                                           
                                                



                     
                                                                               
                                                               



                                 


                                                        
                   







                                                    








                                                  














































































































































































































































































































































































                                                                               
                                                                         




                                                                         



                                                           












                                                             
                                                           



                                                                         





                                                             























                                                                         







                                                                             
 

                                                       
                                                             
                                                               
                                                     
 






                                                             


                                                                 





                                   

                                                                            
                                           
                                                         
                                           


                                
 

                                                                            
                                           
                                                         


                                
 

                                                                                  
                                                 
                                                               
                                           


                                      
 

                                                                           
 

                                                                          









                                                                     
                                                    
                                                                          
                                    
                                                                             
      
 
                
                                                                      









                                                                    
                              






                                                                   
                      



                                                               
                     



                                                                           
                                                             


                                                                         

                                                                      
   
                               
                                                                       

                            
                                                                        
                                                             



                                                   
                                               







                                                            
                                                                                 
 


                                                                
                              


                                       
                                                                              
 

                               

                                                               


                                          
                                                                           
 

                               

                                                                


                                       
                                                                        
 

                               

                                                               


                                          
                                                                           
 

                  

                               

                                                   
                              




                                                                          

 
                                                                        
 

                               

                                                               


                                          
                                                                       
 

                               

                                                               


                                                                   
                                                                          

              


                               

                               

                                                                
 


                                                                 
 

                       

 
                                                                      
 

                               

                                                               
 
                                                                               

 
                                                                         

              


                               

                               

                                                                
 



                                                                              
 

                              






                          
                                                                   


                                                           
                                    

                                                              
                                
 
                                            
                 

                               
                                                                
                                



                 




































                                                                                







































                                                                             



                                     
                                                                       
                                                                            
                                         


                         

                         





                                                         





                                                                           






                                                         





                                                              
                               

                                                                 
                                  
                                 
         

                                                                      











                                                                               


                          

                          
                                 
 
                                 
                     


                                 
/*
 * AppArmor security module
 *
 * This file contains AppArmor LSM hooks.
 *
 * Copyright (C) 1998-2008 Novell/SUSE
 * Copyright 2009-2010 Canonical Ltd.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 */

#include <linux/lsm_hooks.h>
#include <linux/moduleparam.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/ptrace.h>
#include <linux/ctype.h>
#include <linux/sysctl.h>
#include <linux/audit.h>
#include <linux/user_namespace.h>
#include <net/sock.h>

#include "include/apparmor.h"
#include "include/apparmorfs.h"
#include "include/audit.h"
#include "include/capability.h"
#include "include/cred.h"
#include "include/file.h"
#include "include/ipc.h"
#include "include/net.h"
#include "include/path.h"
#include "include/label.h"
#include "include/policy.h"
#include "include/policy_ns.h"
#include "include/procattr.h"
#include "include/mount.h"
#include "include/secid.h"

/* Flag indicating whether initialization completed */
int apparmor_initialized;

DEFINE_PER_CPU(struct aa_buffers, aa_buffers);


/*
 * LSM hook functions
 */

/*
 * put the associated labels
 */
static void apparmor_cred_free(struct cred *cred)
{
	aa_put_label(cred_label(cred));
	cred_label(cred) = NULL;
}

/*
 * allocate the apparmor part of blank credentials
 */
static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
	cred_label(cred) = NULL;
	return 0;
}

/*
 * prepare new cred label for modification by prepare_cred block
 */
static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
				 gfp_t gfp)
{
	cred_label(new) = aa_get_newest_label(cred_label(old));
	return 0;
}

/*
 * transfer the apparmor data to a blank set of creds
 */
static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
{
	cred_label(new) = aa_get_newest_label(cred_label(old));
}

static void apparmor_task_free(struct task_struct *task)
{

	aa_free_task_ctx(task_ctx(task));
	task_ctx(task) = NULL;
}

static int apparmor_task_alloc(struct task_struct *task,
			       unsigned long clone_flags)
{
	struct aa_task_ctx *new = aa_alloc_task_ctx(GFP_KERNEL);

	if (!new)
		return -ENOMEM;

	aa_dup_task_ctx(new, task_ctx(current));
	task_ctx(task) = new;

	return 0;
}

static int apparmor_ptrace_access_check(struct task_struct *child,
					unsigned int mode)
{
	struct aa_label *tracer, *tracee;
	int error;

	tracer = begin_current_label_crit_section();
	tracee = aa_get_task_label(child);
	error = aa_may_ptrace(tracer, tracee,
			(mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
						  : AA_PTRACE_TRACE);
	aa_put_label(tracee);
	end_current_label_crit_section(tracer);

	return error;
}

static int apparmor_ptrace_traceme(struct task_struct *parent)
{
	struct aa_label *tracer, *tracee;
	int error;

	tracee = begin_current_label_crit_section();
	tracer = aa_get_task_label(parent);
	error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
	aa_put_label(tracer);
	end_current_label_crit_section(tracee);

	return error;
}

/* Derived from security/commoncap.c:cap_capget */
static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
{
	struct aa_label *label;
	const struct cred *cred;

	rcu_read_lock();
	cred = __task_cred(target);
	label = aa_get_newest_cred_label(cred);

	/*
	 * cap_capget is stacked ahead of this and will
	 * initialize effective and permitted.
	 */
	if (!unconfined(label)) {
		struct aa_profile *profile;
		struct label_it i;

		label_for_each_confined(i, label, profile) {
			if (COMPLAIN_MODE(profile))
				continue;
			*effective = cap_intersect(*effective,
						   profile->caps.allow);
			*permitted = cap_intersect(*permitted,
						   profile->caps.allow);
		}
	}
	rcu_read_unlock();
	aa_put_label(label);

	return 0;
}

static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
			    int cap, int audit)
{
	struct aa_label *label;
	int error = 0;

	label = aa_get_newest_cred_label(cred);
	if (!unconfined(label))
		error = aa_capable(label, cap, audit);
	aa_put_label(label);

	return error;
}

/**
 * common_perm - basic common permission check wrapper fn for paths
 * @op: operation being checked
 * @path: path to check permission of  (NOT NULL)
 * @mask: requested permissions mask
 * @cond: conditional info for the permission request  (NOT NULL)
 *
 * Returns: %0 else error code if error or permission denied
 */
static int common_perm(const char *op, const struct path *path, u32 mask,
		       struct path_cond *cond)
{
	struct aa_label *label;
	int error = 0;

	label = __begin_current_label_crit_section();
	if (!unconfined(label))
		error = aa_path_perm(op, label, path, 0, mask, cond);
	__end_current_label_crit_section(label);

	return error;
}

/**
 * common_perm_cond - common permission wrapper around inode cond
 * @op: operation being checked
 * @path: location to check (NOT NULL)
 * @mask: requested permissions mask
 *
 * Returns: %0 else error code if error or permission denied
 */
static int common_perm_cond(const char *op, const struct path *path, u32 mask)
{
	struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
				  d_backing_inode(path->dentry)->i_mode
	};

	if (!path_mediated_fs(path->dentry))
		return 0;

	return common_perm(op, path, mask, &cond);
}

/**
 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
 * @op: operation being checked
 * @dir: directory of the dentry  (NOT NULL)
 * @dentry: dentry to check  (NOT NULL)
 * @mask: requested permissions mask
 * @cond: conditional info for the permission request  (NOT NULL)
 *
 * Returns: %0 else error code if error or permission denied
 */
static int common_perm_dir_dentry(const char *op, const struct path *dir,
				  struct dentry *dentry, u32 mask,
				  struct path_cond *cond)
{
	struct path path = { .mnt = dir->mnt, .dentry = dentry };

	return common_perm(op, &path, mask, cond);
}

/**
 * common_perm_rm - common permission wrapper for operations doing rm
 * @op: operation being checked
 * @dir: directory that the dentry is in  (NOT NULL)
 * @dentry: dentry being rm'd  (NOT NULL)
 * @mask: requested permission mask
 *
 * Returns: %0 else error code if error or permission denied
 */
static int common_perm_rm(const char *op, const struct path *dir,
			  struct dentry *dentry, u32 mask)
{
	struct inode *inode = d_backing_inode(dentry);
	struct path_cond cond = { };

	if (!inode || !path_mediated_fs(dentry))
		return 0;

	cond.uid = inode->i_uid;
	cond.mode = inode->i_mode;

	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
}

/**
 * common_perm_create - common permission wrapper for operations doing create
 * @op: operation being checked
 * @dir: directory that dentry will be created in  (NOT NULL)
 * @dentry: dentry to create   (NOT NULL)
 * @mask: request permission mask
 * @mode: created file mode
 *
 * Returns: %0 else error code if error or permission denied
 */
static int common_perm_create(const char *op, const struct path *dir,
			      struct dentry *dentry, u32 mask, umode_t mode)
{
	struct path_cond cond = { current_fsuid(), mode };

	if (!path_mediated_fs(dir->dentry))
		return 0;

	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
}

static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
{
	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
}

static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
			       umode_t mode)
{
	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
				  S_IFDIR);
}

static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
{
	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
}

static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
			       umode_t mode, unsigned int dev)
{
	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
}

static int apparmor_path_truncate(const struct path *path)
{
	return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
}

static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
				 const char *old_name)
{
	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
				  S_IFLNK);
}

static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
			      struct dentry *new_dentry)
{
	struct aa_label *label;
	int error = 0;

	if (!path_mediated_fs(old_dentry))
		return 0;

	label = begin_current_label_crit_section();
	if (!unconfined(label))
		error = aa_path_link(label, old_dentry, new_dir, new_dentry);
	end_current_label_crit_section(label);

	return error;
}

static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
				const struct path *new_dir, struct dentry *new_dentry)
{
	struct aa_label *label;
	int error = 0;

	if (!path_mediated_fs(old_dentry))
		return 0;

	label = begin_current_label_crit_section();
	if (!unconfined(label)) {
		struct path old_path = { .mnt = old_dir->mnt,
					 .dentry = old_dentry };
		struct path new_path = { .mnt = new_dir->mnt,
					 .dentry = new_dentry };
		struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
					  d_backing_inode(old_dentry)->i_mode
		};

		error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
				     MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
				     AA_MAY_SETATTR | AA_MAY_DELETE,
				     &cond);
		if (!error)
			error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
					     0, MAY_WRITE | AA_MAY_SETATTR |
					     AA_MAY_CREATE, &cond);

	}
	end_current_label_crit_section(label);

	return error;
}

static int apparmor_path_chmod(const struct path *path, umode_t mode)
{
	return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
}

static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
{
	return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
}

static int apparmor_inode_getattr(const struct path *path)
{
	return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
}

static int apparmor_file_open(struct file *file)
{
	struct aa_file_ctx *fctx = file_ctx(file);
	struct aa_label *label;
	int error = 0;

	if (!path_mediated_fs(file->f_path.dentry))
		return 0;

	/* If in exec, permission is handled by bprm hooks.
	 * Cache permissions granted by the previous exec check, with
	 * implicit read and executable mmap which are required to
	 * actually execute the image.
	 */
	if (current->in_execve) {
		fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
		return 0;
	}

	label = aa_get_newest_cred_label(file->f_cred);
	if (!unconfined(label)) {
		struct inode *inode = file_inode(file);
		struct path_cond cond = { inode->i_uid, inode->i_mode };

		error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
				     aa_map_file_to_perms(file), &cond);
		/* todo cache full allowed permissions set and state */
		fctx->allow = aa_map_file_to_perms(file);
	}
	aa_put_label(label);

	return error;
}

static int apparmor_file_alloc_security(struct file *file)
{
	int error = 0;

	/* freed by apparmor_file_free_security */
	struct aa_label *label = begin_current_label_crit_section();
	file->f_security = aa_alloc_file_ctx(label, GFP_KERNEL);
	if (!file_ctx(file))
		error = -ENOMEM;
	end_current_label_crit_section(label);

	return error;
}

static void apparmor_file_free_security(struct file *file)
{
	aa_free_file_ctx(file_ctx(file));
}

static int common_file_perm(const char *op, struct file *file, u32 mask)
{
	struct aa_label *label;
	int error = 0;

	/* don't reaudit files closed during inheritance */
	if (file->f_path.dentry == aa_null.dentry)
		return -EACCES;

	label = __begin_current_label_crit_section();
	error = aa_file_perm(op, label, file, mask);
	__end_current_label_crit_section(label);

	return error;
}

static int apparmor_file_receive(struct file *file)
{
	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
}

static int apparmor_file_permission(struct file *file, int mask)
{
	return common_file_perm(OP_FPERM, file, mask);
}

static int apparmor_file_lock(struct file *file, unsigned int cmd)
{
	u32 mask = AA_MAY_LOCK;

	if (cmd == F_WRLCK)
		mask |= MAY_WRITE;

	return common_file_perm(OP_FLOCK, file, mask);
}

static int common_mmap(const char *op, struct file *file, unsigned long prot,
		       unsigned long flags)
{
	int mask = 0;

	if (!file || !file_ctx(file))
		return 0;

	if (prot & PROT_READ)
		mask |= MAY_READ;
	/*
	 * Private mappings don't require write perms since they don't
	 * write back to the files
	 */
	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
		mask |= MAY_WRITE;
	if (prot & PROT_EXEC)
		mask |= AA_EXEC_MMAP;

	return common_file_perm(op, file, mask);
}

static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
			      unsigned long prot, unsigned long flags)
{
	return common_mmap(OP_FMMAP, file, prot, flags);
}

static int apparmor_file_mprotect(struct vm_area_struct *vma,
				  unsigned long reqprot, unsigned long prot)
{
	return common_mmap(OP_FMPROT, vma->vm_file, prot,
			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
}

static int apparmor_sb_mount(const char *dev_name, const struct path *path,
			     const char *type, unsigned long flags, void *data)
{
	struct aa_label *label;
	int error = 0;

	/* Discard magic */
	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
		flags &= ~MS_MGC_MSK;

	flags &= ~AA_MS_IGNORE_MASK;

	label = __begin_current_label_crit_section();
	if (!unconfined(label)) {
		if (flags & MS_REMOUNT)
			error = aa_remount(label, path, flags, data);
		else if (flags & MS_BIND)
			error = aa_bind_mount(label, path, dev_name, flags);
		else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
				  MS_UNBINDABLE))
			error = aa_mount_change_type(label, path, flags);
		else if (flags & MS_MOVE)
			error = aa_move_mount(label, path, dev_name);
		else
			error = aa_new_mount(label, dev_name, path, type,
					     flags, data);
	}
	__end_current_label_crit_section(label);

	return error;
}

static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
{
	struct aa_label *label;
	int error = 0;

	label = __begin_current_label_crit_section();
	if (!unconfined(label))
		error = aa_umount(label, mnt, flags);
	__end_current_label_crit_section(label);

	return error;
}

static int apparmor_sb_pivotroot(const struct path *old_path,
				 const struct path *new_path)
{
	struct aa_label *label;
	int error = 0;

	label = aa_get_current_label();
	if (!unconfined(label))
		error = aa_pivotroot(label, old_path, new_path);
	aa_put_label(label);

	return error;
}

static int apparmor_getprocattr(struct task_struct *task, char *name,
				char **value)
{
	int error = -ENOENT;
	/* released below */
	const struct cred *cred = get_task_cred(task);
	struct aa_task_ctx *ctx = task_ctx(current);
	struct aa_label *label = NULL;

	if (strcmp(name, "current") == 0)
		label = aa_get_newest_label(cred_label(cred));
	else if (strcmp(name, "prev") == 0  && ctx->previous)
		label = aa_get_newest_label(ctx->previous);
	else if (strcmp(name, "exec") == 0 && ctx->onexec)
		label = aa_get_newest_label(ctx->onexec);
	else
		error = -EINVAL;

	if (label)
		error = aa_getprocattr(label, value);

	aa_put_label(label);
	put_cred(cred);

	return error;
}

static int apparmor_setprocattr(const char *name, void *value,
				size_t size)
{
	char *command, *largs = NULL, *args = value;
	size_t arg_size;
	int error;
	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);

	if (size == 0)
		return -EINVAL;

	/* AppArmor requires that the buffer must be null terminated atm */
	if (args[size - 1] != '\0') {
		/* null terminate */
		largs = args = kmalloc(size + 1, GFP_KERNEL);
		if (!args)
			return -ENOMEM;
		memcpy(args, value, size);
		args[size] = '\0';
	}

	error = -EINVAL;
	args = strim(args);
	command = strsep(&args, " ");
	if (!args)
		goto out;
	args = skip_spaces(args);
	if (!*args)
		goto out;

	arg_size = size - (args - (largs ? largs : (char *) value));
	if (strcmp(name, "current") == 0) {
		if (strcmp(command, "changehat") == 0) {
			error = aa_setprocattr_changehat(args, arg_size,
							 AA_CHANGE_NOFLAGS);
		} else if (strcmp(command, "permhat") == 0) {
			error = aa_setprocattr_changehat(args, arg_size,
							 AA_CHANGE_TEST);
		} else if (strcmp(command, "changeprofile") == 0) {
			error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
		} else if (strcmp(command, "permprofile") == 0) {
			error = aa_change_profile(args, AA_CHANGE_TEST);
		} else if (strcmp(command, "stack") == 0) {
			error = aa_change_profile(args, AA_CHANGE_STACK);
		} else
			goto fail;
	} else if (strcmp(name, "exec") == 0) {
		if (strcmp(command, "exec") == 0)
			error = aa_change_profile(args, AA_CHANGE_ONEXEC);
		else if (strcmp(command, "stack") == 0)
			error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
							 AA_CHANGE_STACK));
		else
			goto fail;
	} else
		/* only support the "current" and "exec" process attributes */
		goto fail;

	if (!error)
		error = size;
out:
	kfree(largs);
	return error;

fail:
	aad(&sa)->label = begin_current_label_crit_section();
	aad(&sa)->info = name;
	aad(&sa)->error = error = -EINVAL;
	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
	end_current_label_crit_section(aad(&sa)->label);
	goto out;
}

/**
 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
 * @bprm: binprm for the exec  (NOT NULL)
 */
static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
{
	struct aa_label *label = aa_current_raw_label();
	struct aa_label *new_label = cred_label(bprm->cred);

	/* bail out if unconfined or not changing profile */
	if ((new_label->proxy == label->proxy) ||
	    (unconfined(new_label)))
		return;

	aa_inherit_files(bprm->cred, current->files);

	current->pdeath_signal = 0;

	/* reset soft limits and set hard limits for the new label */
	__aa_transition_rlimits(label, new_label);
}

/**
 * apparmor_bprm_committed_cred - do cleanup after new creds committed
 * @bprm: binprm for the exec  (NOT NULL)
 */
static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
{
	/* clear out temporary/transitional state from the context */
	aa_clear_task_ctx_trans(task_ctx(current));

	return;
}

static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
{
	struct aa_label *label = aa_get_task_label(p);
	*secid = label->secid;
	aa_put_label(label);
}

static int apparmor_task_setrlimit(struct task_struct *task,
		unsigned int resource, struct rlimit *new_rlim)
{
	struct aa_label *label = __begin_current_label_crit_section();
	int error = 0;

	if (!unconfined(label))
		error = aa_task_setrlimit(label, task, resource, new_rlim);
	__end_current_label_crit_section(label);

	return error;
}

static int apparmor_task_kill(struct task_struct *target, struct siginfo *info,
			      int sig, const struct cred *cred)
{
	struct aa_label *cl, *tl;
	int error;

	if (cred) {
		/*
		 * Dealing with USB IO specific behavior
		 */
		cl = aa_get_newest_cred_label(cred);
		tl = aa_get_task_label(target);
		error = aa_may_signal(cl, tl, sig);
		aa_put_label(cl);
		aa_put_label(tl);
		return error;
	}

	cl = __begin_current_label_crit_section();
	tl = aa_get_task_label(target);
	error = aa_may_signal(cl, tl, sig);
	aa_put_label(tl);
	__end_current_label_crit_section(cl);

	return error;
}

/**
 * apparmor_sk_alloc_security - allocate and attach the sk_security field
 */
static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
{
	struct aa_sk_ctx *ctx;

	ctx = kzalloc(sizeof(*ctx), flags);
	if (!ctx)
		return -ENOMEM;

	SK_CTX(sk) = ctx;

	return 0;
}

/**
 * apparmor_sk_free_security - free the sk_security field
 */
static void apparmor_sk_free_security(struct sock *sk)
{
	struct aa_sk_ctx *ctx = SK_CTX(sk);

	SK_CTX(sk) = NULL;
	aa_put_label(ctx->label);
	aa_put_label(ctx->peer);
	kfree(ctx);
}

/**
 * apparmor_clone_security - clone the sk_security field
 */
static void apparmor_sk_clone_security(const struct sock *sk,
				       struct sock *newsk)
{
	struct aa_sk_ctx *ctx = SK_CTX(sk);
	struct aa_sk_ctx *new = SK_CTX(newsk);

	new->label = aa_get_label(ctx->label);
	new->peer = aa_get_label(ctx->peer);
}

/**
 * apparmor_socket_create - check perms before creating a new socket
 */
static int apparmor_socket_create(int family, int type, int protocol, int kern)
{
	struct aa_label *label;
	int error = 0;

	AA_BUG(in_interrupt());

	label = begin_current_label_crit_section();
	if (!(kern || unconfined(label)))
		error = af_select(family,
				  create_perm(label, family, type, protocol),
				  aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
					     family, type, protocol));
	end_current_label_crit_section(label);

	return error;
}

/**
 * apparmor_socket_post_create - setup the per-socket security struct
 *
 * Note:
 * -   kernel sockets currently labeled unconfined but we may want to
 *     move to a special kernel label
 * -   socket may not have sk here if created with sock_create_lite or
 *     sock_alloc. These should be accept cases which will be handled in
 *     sock_graft.
 */
static int apparmor_socket_post_create(struct socket *sock, int family,
				       int type, int protocol, int kern)
{
	struct aa_label *label;

	if (kern) {
		struct aa_ns *ns = aa_get_current_ns();

		label = aa_get_label(ns_unconfined(ns));
		aa_put_ns(ns);
	} else
		label = aa_get_current_label();

	if (sock->sk) {
		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);

		aa_put_label(ctx->label);
		ctx->label = aa_get_label(label);
	}
	aa_put_label(label);

	return 0;
}

/**
 * apparmor_socket_bind - check perms before bind addr to socket
 */
static int apparmor_socket_bind(struct socket *sock,
				struct sockaddr *address, int addrlen)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(!address);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 bind_perm(sock, address, addrlen),
			 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
}

/**
 * apparmor_socket_connect - check perms before connecting @sock to @address
 */
static int apparmor_socket_connect(struct socket *sock,
				   struct sockaddr *address, int addrlen)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(!address);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 connect_perm(sock, address, addrlen),
			 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
}

/**
 * apparmor_socket_list - check perms before allowing listen
 */
static int apparmor_socket_listen(struct socket *sock, int backlog)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 listen_perm(sock, backlog),
			 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
}

/**
 * apparmor_socket_accept - check perms before accepting a new connection.
 *
 * Note: while @newsock is created and has some information, the accept
 *       has not been done.
 */
static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(!newsock);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 accept_perm(sock, newsock),
			 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
}

static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
			    struct msghdr *msg, int size)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(!msg);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 msg_perm(op, request, sock, msg, size),
			 aa_sk_perm(op, request, sock->sk));
}

/**
 * apparmor_socket_sendmsg - check perms before sending msg to another socket
 */
static int apparmor_socket_sendmsg(struct socket *sock,
				   struct msghdr *msg, int size)
{
	return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
}

/**
 * apparmor_socket_recvmsg - check perms before receiving a message
 */
static int apparmor_socket_recvmsg(struct socket *sock,
				   struct msghdr *msg, int size, int flags)
{
	return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
}

/* revaliation, get/set attr, shutdown */
static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 sock_perm(op, request, sock),
			 aa_sk_perm(op, request, sock->sk));
}

/**
 * apparmor_socket_getsockname - check perms before getting the local address
 */
static int apparmor_socket_getsockname(struct socket *sock)
{
	return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
}

/**
 * apparmor_socket_getpeername - check perms before getting remote address
 */
static int apparmor_socket_getpeername(struct socket *sock)
{
	return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
}

/* revaliation, get/set attr, opt */
static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
			    int level, int optname)
{
	AA_BUG(!sock);
	AA_BUG(!sock->sk);
	AA_BUG(in_interrupt());

	return af_select(sock->sk->sk_family,
			 opt_perm(op, request, sock, level, optname),
			 aa_sk_perm(op, request, sock->sk));
}

/**
 * apparmor_getsockopt - check perms before getting socket options
 */
static int apparmor_socket_getsockopt(struct socket *sock, int level,
				      int optname)
{
	return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
				level, optname);
}

/**
 * apparmor_setsockopt - check perms before setting socket options
 */
static int apparmor_socket_setsockopt(struct socket *sock, int level,
				      int optname)
{
	return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
				level, optname);
}

/**
 * apparmor_socket_shutdown - check perms before shutting down @sock conn
 */
static int apparmor_socket_shutdown(struct socket *sock, int how)
{
	return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
}

/**
 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
 *
 * Note: can not sleep may be called with locks held
 *
 * dont want protocol specific in __skb_recv_datagram()
 * to deny an incoming connection  socket_sock_rcv_skb()
 */
static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	return 0;
}


static struct aa_label *sk_peer_label(struct sock *sk)
{
	struct aa_sk_ctx *ctx = SK_CTX(sk);

	if (ctx->peer)
		return ctx->peer;

	return ERR_PTR(-ENOPROTOOPT);
}

/**
 * apparmor_socket_getpeersec_stream - get security context of peer
 *
 * Note: for tcp only valid if using ipsec or cipso on lan
 */
static int apparmor_socket_getpeersec_stream(struct socket *sock,
					     char __user *optval,
					     int __user *optlen,
					     unsigned int len)
{
	char *name;
	int slen, error = 0;
	struct aa_label *label;
	struct aa_label *peer;

	label = begin_current_label_crit_section();
	peer = sk_peer_label(sock->sk);
	if (IS_ERR(peer)) {
		error = PTR_ERR(peer);
		goto done;
	}
	slen = aa_label_asxprint(&name, labels_ns(label), peer,
				 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
				 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
	/* don't include terminating \0 in slen, it breaks some apps */
	if (slen < 0) {
		error = -ENOMEM;
	} else {
		if (slen > len) {
			error = -ERANGE;
		} else if (copy_to_user(optval, name, slen)) {
			error = -EFAULT;
			goto out;
		}
		if (put_user(slen, optlen))
			error = -EFAULT;
out:
		kfree(name);

	}

done:
	end_current_label_crit_section(label);

	return error;
}

/**
 * apparmor_socket_getpeersec_dgram - get security label of packet
 * @sock: the peer socket
 * @skb: packet data
 * @secid: pointer to where to put the secid of the packet
 *
 * Sets the netlabel socket state on sk from parent
 */
static int apparmor_socket_getpeersec_dgram(struct socket *sock,
					    struct sk_buff *skb, u32 *secid)

{
	/* TODO: requires secid support */
	return -ENOPROTOOPT;
}

/**
 * apparmor_sock_graft - Initialize newly created socket
 * @sk: child sock
 * @parent: parent socket
 *
 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
 *       just set sk security information off of current creating process label
 *       Labeling of sk for accept case - probably should be sock based
 *       instead of task, because of the case where an implicitly labeled
 *       socket is shared by different tasks.
 */
static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
{
	struct aa_sk_ctx *ctx = SK_CTX(sk);

	if (!ctx->label)
		ctx->label = aa_get_current_label();
}

static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
	LSM_HOOK_INIT(capget, apparmor_capget),
	LSM_HOOK_INIT(capable, apparmor_capable),

	LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
	LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
	LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),

	LSM_HOOK_INIT(path_link, apparmor_path_link),
	LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
	LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
	LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
	LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
	LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
	LSM_HOOK_INIT(path_rename, apparmor_path_rename),
	LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
	LSM_HOOK_INIT(path_chown, apparmor_path_chown),
	LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
	LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),

	LSM_HOOK_INIT(file_open, apparmor_file_open),
	LSM_HOOK_INIT(file_receive, apparmor_file_receive),
	LSM_HOOK_INIT(file_permission, apparmor_file_permission),
	LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
	LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
	LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
	LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
	LSM_HOOK_INIT(file_lock, apparmor_file_lock),

	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),

	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),

	LSM_HOOK_INIT(socket_create, apparmor_socket_create),
	LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
	LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
	LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
	LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
	LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
	LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
	LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
	LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
	LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
	LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
	LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
	LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
	LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
	LSM_HOOK_INIT(socket_getpeersec_stream,
		      apparmor_socket_getpeersec_stream),
	LSM_HOOK_INIT(socket_getpeersec_dgram,
		      apparmor_socket_getpeersec_dgram),
	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),

	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
	LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
	LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),

	LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
	LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
	LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),

	LSM_HOOK_INIT(task_free, apparmor_task_free),
	LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
	LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
	LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
	LSM_HOOK_INIT(task_kill, apparmor_task_kill),

#ifdef CONFIG_AUDIT
	LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
	LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
	LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
	LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
#endif

	LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
	LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
	LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
};

/*
 * AppArmor sysfs module parameters
 */

static int param_set_aabool(const char *val, const struct kernel_param *kp);
static int param_get_aabool(char *buffer, const struct kernel_param *kp);
#define param_check_aabool param_check_bool
static const struct kernel_param_ops param_ops_aabool = {
	.flags = KERNEL_PARAM_OPS_FL_NOARG,
	.set = param_set_aabool,
	.get = param_get_aabool
};

static int param_set_aauint(const char *val, const struct kernel_param *kp);
static int param_get_aauint(char *buffer, const struct kernel_param *kp);
#define param_check_aauint param_check_uint
static const struct kernel_param_ops param_ops_aauint = {
	.set = param_set_aauint,
	.get = param_get_aauint
};

static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
#define param_check_aalockpolicy param_check_bool
static const struct kernel_param_ops param_ops_aalockpolicy = {
	.flags = KERNEL_PARAM_OPS_FL_NOARG,
	.set = param_set_aalockpolicy,
	.get = param_get_aalockpolicy
};

static int param_set_audit(const char *val, const struct kernel_param *kp);
static int param_get_audit(char *buffer, const struct kernel_param *kp);

static int param_set_mode(const char *val, const struct kernel_param *kp);
static int param_get_mode(char *buffer, const struct kernel_param *kp);

/* Flag values, also controllable via /sys/module/apparmor/parameters
 * We define special types as we want to do additional mediation.
 */

/* AppArmor global enforcement switch - complain, enforce, kill */
enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
module_param_call(mode, param_set_mode, param_get_mode,
		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);

/* whether policy verification hashing is enabled */
bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
#ifdef CONFIG_SECURITY_APPARMOR_HASH
module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
#endif

/* Debug mode */
bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);

/* Audit mode */
enum audit_mode aa_g_audit;
module_param_call(audit, param_set_audit, param_get_audit,
		  &aa_g_audit, S_IRUSR | S_IWUSR);

/* Determines if audit header is included in audited messages.  This
 * provides more context if the audit daemon is not running
 */
bool aa_g_audit_header = true;
module_param_named(audit_header, aa_g_audit_header, aabool,
		   S_IRUSR | S_IWUSR);

/* lock out loading/removal of policy
 * TODO: add in at boot loading of policy, which is the only way to
 *       load policy, if lock_policy is set
 */
bool aa_g_lock_policy;
module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
		   S_IRUSR | S_IWUSR);

/* Syscall logging mode */
bool aa_g_logsyscall;
module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);

/* Maximum pathname length before accesses will start getting rejected */
unsigned int aa_g_path_max = 2 * PATH_MAX;
module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);

/* Determines how paranoid loading of policy is and how much verification
 * on the loaded policy is done.
 * DEPRECATED: read only as strict checking of load is always done now
 * that none root users (user namespaces) can load policy.
 */
bool aa_g_paranoid_load = true;
module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);

/* Boot time disable flag */
static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);

static int __init apparmor_enabled_setup(char *str)
{
	unsigned long enabled;
	int error = kstrtoul(str, 0, &enabled);
	if (!error)
		apparmor_enabled = enabled ? 1 : 0;
	return 1;
}

__setup("apparmor=", apparmor_enabled_setup);

/* set global flag turning off the ability to load policy */
static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_admin_capable(NULL))
		return -EPERM;
	return param_set_bool(val, kp);
}

static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_view_capable(NULL))
		return -EPERM;
	return param_get_bool(buffer, kp);
}

static int param_set_aabool(const char *val, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_admin_capable(NULL))
		return -EPERM;
	return param_set_bool(val, kp);
}

static int param_get_aabool(char *buffer, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_view_capable(NULL))
		return -EPERM;
	return param_get_bool(buffer, kp);
}

static int param_set_aauint(const char *val, const struct kernel_param *kp)
{
	int error;

	if (!apparmor_enabled)
		return -EINVAL;
	/* file is ro but enforce 2nd line check */
	if (apparmor_initialized)
		return -EPERM;

	error = param_set_uint(val, kp);
	pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);

	return error;
}

static int param_get_aauint(char *buffer, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_view_capable(NULL))
		return -EPERM;
	return param_get_uint(buffer, kp);
}

static int param_get_audit(char *buffer, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_view_capable(NULL))
		return -EPERM;
	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
}

static int param_set_audit(const char *val, const struct kernel_param *kp)
{
	int i;

	if (!apparmor_enabled)
		return -EINVAL;
	if (!val)
		return -EINVAL;
	if (apparmor_initialized && !policy_admin_capable(NULL))
		return -EPERM;

	i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
	if (i < 0)
		return -EINVAL;

	aa_g_audit = i;
	return 0;
}

static int param_get_mode(char *buffer, const struct kernel_param *kp)
{
	if (!apparmor_enabled)
		return -EINVAL;
	if (apparmor_initialized && !policy_view_capable(NULL))
		return -EPERM;

	return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
}

static int param_set_mode(const char *val, const struct kernel_param *kp)
{
	int i;

	if (!apparmor_enabled)
		return -EINVAL;
	if (!val)
		return -EINVAL;
	if (apparmor_initialized && !policy_admin_capable(NULL))
		return -EPERM;

	i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
			 val);
	if (i < 0)
		return -EINVAL;

	aa_g_profile_mode = i;
	return 0;
}

/*
 * AppArmor init functions
 */

/**
 * set_init_ctx - set a task context and profile on the first task.
 *
 * TODO: allow setting an alternate profile than unconfined
 */
static int __init set_init_ctx(void)
{
	struct cred *cred = (struct cred *)current->real_cred;
	struct aa_task_ctx *ctx;

	ctx = aa_alloc_task_ctx(GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	cred_label(cred) = aa_get_label(ns_unconfined(root_ns));
	task_ctx(current) = ctx;

	return 0;
}

static void destroy_buffers(void)
{
	u32 i, j;

	for_each_possible_cpu(i) {
		for_each_cpu_buffer(j) {
			kfree(per_cpu(aa_buffers, i).buf[j]);
			per_cpu(aa_buffers, i).buf[j] = NULL;
		}
	}
}

static int __init alloc_buffers(void)
{
	u32 i, j;

	for_each_possible_cpu(i) {
		for_each_cpu_buffer(j) {
			char *buffer;

			if (cpu_to_node(i) > num_online_nodes())
				/* fallback to kmalloc for offline nodes */
				buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
			else
				buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
						      cpu_to_node(i));
			if (!buffer) {
				destroy_buffers();
				return -ENOMEM;
			}
			per_cpu(aa_buffers, i).buf[j] = buffer;
		}
	}

	return 0;
}

#ifdef CONFIG_SYSCTL
static int apparmor_dointvec(struct ctl_table *table, int write,
			     void __user *buffer, size_t *lenp, loff_t *ppos)
{
	if (!policy_admin_capable(NULL))
		return -EPERM;
	if (!apparmor_enabled)
		return -EINVAL;

	return proc_dointvec(table, write, buffer, lenp, ppos);
}

static struct ctl_path apparmor_sysctl_path[] = {
	{ .procname = "kernel", },
	{ }
};

static struct ctl_table apparmor_sysctl_table[] = {
	{
		.procname       = "unprivileged_userns_apparmor_policy",
		.data           = &unprivileged_userns_apparmor_policy,
		.maxlen         = sizeof(int),
		.mode           = 0600,
		.proc_handler   = apparmor_dointvec,
	},
	{ }
};

static int __init apparmor_init_sysctl(void)
{
	return register_sysctl_paths(apparmor_sysctl_path,
				     apparmor_sysctl_table) ? 0 : -ENOMEM;
}
#else
static inline int apparmor_init_sysctl(void)
{
	return 0;
}
#endif /* CONFIG_SYSCTL */

static int __init apparmor_init(void)
{
	int error;

	if (!apparmor_enabled || !security_module_enable("apparmor")) {
		aa_info_message("AppArmor disabled by boot time parameter");
		apparmor_enabled = false;
		return 0;
	}

	aa_secids_init();

	error = aa_setup_dfa_engine();
	if (error) {
		AA_ERROR("Unable to setup dfa engine\n");
		goto alloc_out;
	}

	error = aa_alloc_root_ns();
	if (error) {
		AA_ERROR("Unable to allocate default profile namespace\n");
		goto alloc_out;
	}

	error = apparmor_init_sysctl();
	if (error) {
		AA_ERROR("Unable to register sysctls\n");
		goto alloc_out;

	}

	error = alloc_buffers();
	if (error) {
		AA_ERROR("Unable to allocate work buffers\n");
		goto buffers_out;
	}

	error = set_init_ctx();
	if (error) {
		AA_ERROR("Failed to set context on init task\n");
		aa_free_root_ns();
		goto buffers_out;
	}
	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
				"apparmor");

	/* Report that AppArmor successfully initialized */
	apparmor_initialized = 1;
	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
		aa_info_message("AppArmor initialized: complain mode enabled");
	else if (aa_g_profile_mode == APPARMOR_KILL)
		aa_info_message("AppArmor initialized: kill mode enabled");
	else
		aa_info_message("AppArmor initialized");

	return error;

buffers_out:
	destroy_buffers();

alloc_out:
	aa_destroy_aafs();
	aa_teardown_dfa_engine();

	apparmor_enabled = false;
	return error;
}

security_initcall(apparmor_init);