linux/fs/reiserfs/xattr_security.c
Andreas Gruenbacher d9a82a0403 xattr handlers: Pass handler to operations instead of flags
The xattr_handler operations are currently all passed a file system
specific flags value which the operations can use to disambiguate between
different handlers; some file systems use that to distinguish the xattr
namespace, for example.  In some oprations, it would be useful to also have
access to the handler prefix.  To allow that, pass a pointer to the handler
to operations instead of the flags value alone.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-13 20:34:32 -05:00

122 lines
3.0 KiB
C

#include "reiserfs.h"
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/slab.h>
#include "xattr.h"
#include <linux/security.h>
#include <linux/uaccess.h>
static int
security_get(const struct xattr_handler *handler, struct dentry *dentry,
const char *name, void *buffer, size_t size)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(d_inode(dentry)))
return -EPERM;
return reiserfs_xattr_get(d_inode(dentry), name, buffer, size);
}
static int
security_set(const struct xattr_handler *handler, struct dentry *dentry,
const char *name, const void *buffer, size_t size, int flags)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(d_inode(dentry)))
return -EPERM;
return reiserfs_xattr_set(d_inode(dentry), name, buffer, size, flags);
}
static size_t security_list(const struct xattr_handler *handler,
struct dentry *dentry, char *list, size_t list_len,
const char *name, size_t namelen)
{
const size_t len = namelen + 1;
if (IS_PRIVATE(d_inode(dentry)))
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,
const struct qstr *qstr,
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_old_inode_init_security(inode, dir, qstr, &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 && reiserfs_xattrs_initialized(inode->i_sb)) {
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;
}
const struct xattr_handler reiserfs_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = security_get,
.set = security_set,
.list = security_list,
};