role_mouse:RMDIR,RENAME,MKDIR;
role_cow:RENAME,RMDIR;
role_tiger:RMDIR,MKDIR;
role_rabbit:RENAME,MKDIR;
role_dragon:MKDIR;
role_snake:RENAME;
role_horse:RMDIR;

1001:role_tiger
1002:role_cow:
1003:role_tiger:

/*
 * Path:include/linux/lsm_hooks.h
 * Description:Security module hook list structure
 *             For use with generic list macros for common operations
 * 
 * */
struct security_hook_list hooks[] = {
    /* Desc:Initializeing a security_hook_list structure takes 
     * up a lot of space in a source file. This macro takes 
     * care of the common case and reduces the amount of 
     * text incolved
     * */
    LSM_HOOK_INIT(inode_mkdir, mkdir_hook),
    LSM_HOOK_INIT(inode_rmdir, rmdir_hook),
    LSM_HOOK_INIT(inode_rename, rename_hook)
};

int mkdir_hook(struct inode *dir, struct dentry *dentry, umode_t mode){
    int gate = lsm_enabled(); 			//查看lsm开启/关闭状态
    int cur_cap;
    int flag;
    if(!gate){
        return 0;
    }
    printk("[Hook mkdir successfully!]");
    cur_cap = get_user_config(); 		//获取user_config以及其对应的role,关键函数
    flag = check_mkdir_auth(cur_cap);
    if(flag){
        printk(KERN_INFO "[+]mkdir accessble");
        return PASS;
    }else{
        printk(KERN_WARNING "[x]You have no permission");
        return NOPASS;
    }
}

int rmdir_hook(struct inode *dir, struct dentry *dentry){
    int gate = lsm_enabled();
    int cur_cap;
    int flag;
    if(!gate){
        return 0;
    }
    printk("[Hook rmdir successfully!]");
    cur_cap = get_user_config();
    flag = check_rmdir_auth(cur_cap);
    if(flag){
        return PASS;
    }else{
        return NOPASS;
    }
}
int rename_hook(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry){
    int gate = lsm_enabled();
    int cur_cap;
    int flag;
    if(!gate){
        return 0;
    }
    printk("[Hook rename successfully!]");
    cur_cap = get_user_config();
    flag = check_rename_auth(cur_cap);
    if(flag){
        return PASS;
    }else{
        return NOPASS;
    }
}

@inode_mkdir:                                                          
 Check permissions to create a new directory in the existing directory 
 associated with inode structure @dir.                                 
 @dir contains the inode structure of parent of the directory          
 to be created.                                                        
 @dentry contains the dentry structure of new directory.               
 @mode contains the mode of new directory.                             
 Return 0 if permission is granted.                                    

static struct security_hook_list pwh_hooks[] __lsm_ro_after_init = {
    /* Desc:Initializeing a security_hook_list structure takes 
     * up a lot of space in a source file. This macro takes 
     * care of the common case and reduces the amount of 
     * text incolved
     * */
    LSM_HOOK_INIT(inode_mkdir, pwh_mkdir_hook),
    LSM_HOOK_INIT(inode_rmdir, pwh_inode_rmdir),
    LSM_HOOK_INIT(inode_rename, pwh_inode_rename), 
};

void __init pwh_add_hooks(void){
    printk(KERN_WARNING "[LSM_INIT]\n");
    security_add_hooks(pwh_hooks,ARRAY_SIZE(pwh_hooks), "pwh");

}

static int __init pwh_init(void){
    pwh_add_hooks();
    return 0;
}

__initcall(pwh_init);