alistair23-linux/fs/reiserfs/xattr_security.c
Christoph Hellwig 431547b3c4 sanitize xattr handler prototypes
Add a flags argument to struct xattr_handler and pass it to all xattr
handler methods.  This allows using the same methods for multiple
handlers, e.g. for the ACL methods which perform exactly the same action
for the access and default ACLs, just using a different underlying
attribute.  With a little more groundwork it'll also allow sharing the
methods for the regular user/trusted/secure handlers in extN, ocfs2 and
jffs2 like it's already done for xfs in this patch.

Also change the inode argument to the handlers to a dentry to allow
using the handlers mechnism for filesystems that require it later,
e.g. cifs.

[with GFS2 bits updated by Steven Whitehouse <swhiteho@redhat.com>]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:49 -05:00

119 lines
2.8 KiB
C

#include <linux/reiserfs_fs.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/security.h>
#include <asm/uaccess.h>
static int
security_get(struct dentry *dentry, const char *name, void *buffer, size_t size,
int handler_flags)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(dentry->d_inode))
return -EPERM;
return reiserfs_xattr_get(dentry->d_inode, name, buffer, size);
}
static int
security_set(struct dentry *dentry, const char *name, const void *buffer,
size_t size, int flags, int handler_flags)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(dentry->d_inode))
return -EPERM;
return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags);
}
static size_t security_list(struct dentry *dentry, char *list, size_t list_len,
const char *name, size_t namelen, int handler_flags)
{
const size_t len = namelen + 1;
if (IS_PRIVATE(dentry->d_inode))
return 0;
if (list && len <= list_len) {
memcpy(list, name, namelen);
list[namelen] = '\0';
}
return len;
}
/* Initializes the security context for a new inode and returns the number
* of blocks needed for the transaction. If successful, reiserfs_security
* must be released using reiserfs_security_free when the caller is done. */
int reiserfs_security_init(struct inode *dir, struct inode *inode,
struct reiserfs_security_handle *sec)
{
int blocks = 0;
int error;
sec->name = NULL;
/* Don't add selinux attributes on xattrs - they'll never get used */
if (IS_PRIVATE(dir))
return 0;
error = security_inode_init_security(inode, dir, &sec->name,
&sec->value, &sec->length);
if (error) {
if (error == -EOPNOTSUPP)
error = 0;
sec->name = NULL;
sec->value = NULL;
sec->length = 0;
return error;
}
if (sec->length) {
blocks = reiserfs_xattr_jcreate_nblocks(inode) +
reiserfs_xattr_nblocks(inode, sec->length);
/* We don't want to count the directories twice if we have
* a default ACL. */
REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
}
return blocks;
}
int reiserfs_security_write(struct reiserfs_transaction_handle *th,
struct inode *inode,
struct reiserfs_security_handle *sec)
{
int error;
if (strlen(sec->name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
error = reiserfs_xattr_set_handle(th, inode, sec->name, sec->value,
sec->length, XATTR_CREATE);
if (error == -ENODATA || error == -EOPNOTSUPP)
error = 0;
return error;
}
void reiserfs_security_free(struct reiserfs_security_handle *sec)
{
kfree(sec->name);
kfree(sec->value);
sec->name = NULL;
sec->value = NULL;
}
struct xattr_handler reiserfs_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = security_get,
.set = security_set,
.list = security_list,
};