linux-sg2042/fs/ext4/xattr_security.c

78 lines
1.8 KiB
C

/*
* linux/fs/ext4/xattr_security.c
* Handler for storing security labels as extended attributes.
*/
#include <linux/module.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/smp_lock.h>
#include <linux/ext4_jbd2.h>
#include <linux/ext4_fs.h>
#include <linux/security.h>
#include "xattr.h"
static size_t
ext4_xattr_security_list(struct inode *inode, char *list, size_t list_size,
const char *name, size_t name_len)
{
const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
const size_t total_len = prefix_len + name_len + 1;
if (list && total_len <= list_size) {
memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
memcpy(list+prefix_len, name, name_len);
list[prefix_len + name_len] = '\0';
}
return total_len;
}
static int
ext4_xattr_security_get(struct inode *inode, const char *name,
void *buffer, size_t size)
{
if (strcmp(name, "") == 0)
return -EINVAL;
return ext4_xattr_get(inode, EXT4_XATTR_INDEX_SECURITY, name,
buffer, size);
}
static int
ext4_xattr_security_set(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
if (strcmp(name, "") == 0)
return -EINVAL;
return ext4_xattr_set(inode, EXT4_XATTR_INDEX_SECURITY, name,
value, size, flags);
}
int
ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir)
{
int err;
size_t len;
void *value;
char *name;
err = security_inode_init_security(inode, dir, &name, &value, &len);
if (err) {
if (err == -EOPNOTSUPP)
return 0;
return err;
}
err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY,
name, value, len, 0);
kfree(name);
kfree(value);
return err;
}
struct xattr_handler ext4_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.list = ext4_xattr_security_list,
.get = ext4_xattr_security_get,
.set = ext4_xattr_security_set,
};