4 * Copyright (C) 2005 Greg Kroah-Hartman <gregkh@suse.de>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version
8 * 2 as published by the Free Software Foundation.
10 * Based on fs/debugfs/inode.c which had the following copyright notice:
11 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
12 * Copyright (C) 2004 IBM Inc.
16 #include <linux/module.h>
18 #include <linux/mount.h>
19 #include <linux/pagemap.h>
20 #include <linux/init.h>
21 #include <linux/namei.h>
22 #include <linux/security.h>
23 #include <linux/magic.h>
25 static struct vfsmount
*mount
;
26 static int mount_count
;
28 static int fill_super(struct super_block
*sb
, void *data
, int silent
)
30 static struct tree_descr files
[] = {{""}};
32 return simple_fill_super(sb
, SECURITYFS_MAGIC
, files
);
35 static struct dentry
*get_sb(struct file_system_type
*fs_type
,
36 int flags
, const char *dev_name
,
39 return mount_single(fs_type
, flags
, data
, fill_super
);
42 static struct file_system_type fs_type
= {
46 .kill_sb
= kill_litter_super
,
49 int securityfs_pin_fs(void)
51 return simple_pin_fs(&fs_type
, &mount
, &mount_count
);
54 int __securityfs_setup_d_inode(struct inode
*dir
, struct dentry
*dentry
,
55 umode_t mode
, void *data
,
56 const struct file_operations
*fops
,
57 const struct inode_operations
*iops
)
59 bool is_dir
= S_ISDIR(mode
);
60 struct inode
*inode
= new_inode(dir
->i_sb
);
64 inode
->i_ino
= get_next_ino();
66 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
67 inode
->i_private
= data
;
69 inode
->i_op
= iops
? iops
: &simple_dir_inode_operations
;
70 inode
->i_fop
= &simple_dir_operations
;
76 d_instantiate(dentry
, inode
);
81 EXPORT_SYMBOL_GPL(__securityfs_setup_d_inode
);
84 * securityfs_create_dentry - create a file/dir in the securityfs filesystem
86 * @name: a pointer to a string containing the name of the file to create.
87 * @mode: the permission that the file should have
88 * @parent: a pointer to the parent dentry for this file. This should be a
89 * directory dentry if set. If this parameter is %NULL, then the
90 * file will be created in the root of the securityfs filesystem.
91 * @data: a pointer to something that the caller will want to get to later
92 * on. The inode.i_private pointer will point to this value on
94 * @fops: a pointer to a struct file_operations that should be used for
96 * @iops: a point to a struct of inode_operations that should be used for
99 * This is the basic "create a xxx" function for securityfs. It allows for a
100 * wide range of flexibility in creating a file, or a directory (if you
101 * want to create a directory, the securityfs_create_dir() function is
102 * recommended to be used instead).
104 * This function returns a pointer to a dentry if it succeeds. This
105 * pointer must be passed to the securityfs_remove() function when the file is
106 * to be removed (no automatic cleanup happens if your module is unloaded,
107 * you are responsible here). If an error occurs, the function will return
108 * the error value (via ERR_PTR).
110 * If securityfs is not enabled in the kernel, the value %-ENODEV is
113 struct dentry
*securityfs_create_dentry(const char *name
, umode_t mode
,
114 struct dentry
*parent
, void *data
,
115 const struct file_operations
*fops
,
116 const struct inode_operations
*iops
)
118 struct dentry
*dentry
;
119 int is_dir
= S_ISDIR(mode
);
125 mode
= (mode
& S_IALLUGO
) | S_IFREG
;
128 pr_debug("securityfs: creating file '%s'\n",name
);
130 error
= simple_pin_fs(&fs_type
, &mount
, &mount_count
);
132 return ERR_PTR(error
);
135 parent
= mount
->mnt_root
;
137 dir
= d_inode(parent
);
140 dentry
= lookup_one_len(name
, parent
, strlen(name
));
144 if (d_really_is_positive(dentry
)) {
149 error
= __securityfs_setup_d_inode(dir
, dentry
, mode
, data
, fops
, iops
);
157 dentry
= ERR_PTR(error
);
160 simple_release_fs(&mount
, &mount_count
);
163 EXPORT_SYMBOL_GPL(securityfs_create_dentry
);
166 * securityfs_create_file - create a file in the securityfs filesystem
168 * @name: a pointer to a string containing the name of the file to create.
169 * @mode: the permission that the file should have
170 * @parent: a pointer to the parent dentry for this file. This should be a
171 * directory dentry if set. If this parameter is %NULL, then the
172 * file will be created in the root of the securityfs filesystem.
173 * @data: a pointer to something that the caller will want to get to later
174 * on. The inode.i_private pointer will point to this value on
176 * @fops: a pointer to a struct file_operations that should be used for
179 * This function creates a file in securityfs with the given @name.
181 * This function returns a pointer to a dentry if it succeeds. This
182 * pointer must be passed to the securityfs_remove() function when the file is
183 * to be removed (no automatic cleanup happens if your module is unloaded,
184 * you are responsible here). If an error occurs, the function will return
185 * the error value (via ERR_PTR).
187 * If securityfs is not enabled in the kernel, the value %-ENODEV is
190 struct dentry
*securityfs_create_file(const char *name
, umode_t mode
,
191 struct dentry
*parent
, void *data
,
192 const struct file_operations
*fops
)
194 return securityfs_create_dentry(name
, mode
, parent
, data
, fops
, NULL
);
196 EXPORT_SYMBOL_GPL(securityfs_create_file
);
199 * securityfs_create_dir - create a directory in the securityfs filesystem
201 * @name: a pointer to a string containing the name of the directory to
203 * @parent: a pointer to the parent dentry for this file. This should be a
204 * directory dentry if set. If this parameter is %NULL, then the
205 * directory will be created in the root of the securityfs filesystem.
207 * This function creates a directory in securityfs with the given @name.
209 * This function returns a pointer to a dentry if it succeeds. This
210 * pointer must be passed to the securityfs_remove() function when the file is
211 * to be removed (no automatic cleanup happens if your module is unloaded,
212 * you are responsible here). If an error occurs, the function will return
213 * the error value (via ERR_PTR).
215 * If securityfs is not enabled in the kernel, the value %-ENODEV is
218 struct dentry
*securityfs_create_dir(const char *name
, struct dentry
*parent
)
220 return securityfs_create_file(name
,
221 S_IFDIR
| S_IRWXU
| S_IRUGO
| S_IXUGO
,
224 EXPORT_SYMBOL_GPL(securityfs_create_dir
);
227 * securityfs_remove - removes a file or directory from the securityfs filesystem
229 * @dentry: a pointer to a the dentry of the file or directory to be removed.
231 * This function removes a file or directory in securityfs that was previously
232 * created with a call to another securityfs function (like
233 * securityfs_create_file() or variants thereof.)
235 * This function is required to be called in order for the file to be
236 * removed. No automatic cleanup of files will happen when a module is
237 * removed; you are responsible here.
239 void securityfs_remove(struct dentry
*dentry
)
243 if (!dentry
|| IS_ERR(dentry
))
246 dir
= d_inode(dentry
->d_parent
);
248 if (simple_positive(dentry
)) {
249 if (d_is_dir(dentry
))
250 simple_rmdir(dir
, dentry
);
252 simple_unlink(dir
, dentry
);
256 simple_release_fs(&mount
, &mount_count
);
258 EXPORT_SYMBOL_GPL(securityfs_remove
);
260 static int __init
securityfs_init(void)
264 retval
= sysfs_create_mount_point(kernel_kobj
, "security");
268 retval
= register_filesystem(&fs_type
);
270 sysfs_remove_mount_point(kernel_kobj
, "security");
274 core_initcall(securityfs_init
);
275 MODULE_LICENSE("GPL");