remarkable-linux/include/linux/reiserfs_xattr.h
Eric Paris 2a7dba391e fs/vfs/security: pass last path component to LSM on inode creation
SELinux would like to implement a new labeling behavior of newly created
inodes.  We currently label new inodes based on the parent and the creating
process.  This new behavior would also take into account the name of the
new object when deciding the new label.  This is not the (supposed) full path,
just the last component of the path.

This is very useful because creating /etc/shadow is different than creating
/etc/passwd but the kernel hooks are unable to differentiate these
operations.  We currently require that userspace realize it is doing some
difficult operation like that and than userspace jumps through SELinux hoops
to get things set up correctly.  This patch does not implement new
behavior, that is obviously contained in a seperate SELinux patch, but it
does pass the needed name down to the correct LSM hook.  If no such name
exists it is fine to pass NULL.

Signed-off-by: Eric Paris <eparis@redhat.com>
2011-02-01 11:12:29 -05:00

153 lines
4.5 KiB
C

/*
File: linux/reiserfs_xattr.h
*/
#ifndef _LINUX_REISERFS_XATTR_H
#define _LINUX_REISERFS_XATTR_H
#include <linux/types.h>
/* Magic value in header */
#define REISERFS_XATTR_MAGIC 0x52465841 /* "RFXA" */
struct reiserfs_xattr_header {
__le32 h_magic; /* magic number for identification */
__le32 h_hash; /* hash of the value */
};
struct reiserfs_security_handle {
char *name;
void *value;
size_t length;
};
#ifdef __KERNEL__
#include <linux/init.h>
#include <linux/list.h>
#include <linux/rwsem.h>
#include <linux/reiserfs_fs_i.h>
#include <linux/reiserfs_fs.h>
struct inode;
struct dentry;
struct iattr;
struct super_block;
struct nameidata;
int reiserfs_xattr_register_handlers(void) __init;
void reiserfs_xattr_unregister_handlers(void);
int reiserfs_xattr_init(struct super_block *sb, int mount_flags);
int reiserfs_lookup_privroot(struct super_block *sb);
int reiserfs_delete_xattrs(struct inode *inode);
int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs);
int reiserfs_permission(struct inode *inode, int mask, unsigned int flags);
#ifdef CONFIG_REISERFS_FS_XATTR
#define has_xattr_dir(inode) (REISERFS_I(inode)->i_flags & i_has_xattr_dir)
ssize_t reiserfs_getxattr(struct dentry *dentry, const char *name,
void *buffer, size_t size);
int reiserfs_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags);
ssize_t reiserfs_listxattr(struct dentry *dentry, char *buffer, size_t size);
int reiserfs_removexattr(struct dentry *dentry, const char *name);
int reiserfs_xattr_get(struct inode *, const char *, void *, size_t);
int reiserfs_xattr_set(struct inode *, const char *, const void *, size_t, int);
int reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *,
struct inode *, const char *, const void *,
size_t, int);
extern const struct xattr_handler reiserfs_xattr_user_handler;
extern const struct xattr_handler reiserfs_xattr_trusted_handler;
extern const struct xattr_handler reiserfs_xattr_security_handler;
#ifdef CONFIG_REISERFS_FS_SECURITY
int reiserfs_security_init(struct inode *dir, struct inode *inode,
const struct qstr *qstr,
struct reiserfs_security_handle *sec);
int reiserfs_security_write(struct reiserfs_transaction_handle *th,
struct inode *inode,
struct reiserfs_security_handle *sec);
void reiserfs_security_free(struct reiserfs_security_handle *sec);
#endif
static inline int reiserfs_xattrs_initialized(struct super_block *sb)
{
return REISERFS_SB(sb)->priv_root != NULL;
}
#define xattr_size(size) ((size) + sizeof(struct reiserfs_xattr_header))
static inline loff_t reiserfs_xattr_nblocks(struct inode *inode, loff_t size)
{
loff_t ret = 0;
if (reiserfs_file_data_log(inode)) {
ret = _ROUND_UP(xattr_size(size), inode->i_sb->s_blocksize);
ret >>= inode->i_sb->s_blocksize_bits;
}
return ret;
}
/* We may have to create up to 3 objects: xattr root, xattr dir, xattr file.
* Let's try to be smart about it.
* xattr root: We cache it. If it's not cached, we may need to create it.
* xattr dir: If anything has been loaded for this inode, we can set a flag
* saying so.
* xattr file: Since we don't cache xattrs, we can't tell. We always include
* blocks for it.
*
* However, since root and dir can be created between calls - YOU MUST SAVE
* THIS VALUE.
*/
static inline size_t reiserfs_xattr_jcreate_nblocks(struct inode *inode)
{
size_t nblocks = JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
if ((REISERFS_I(inode)->i_flags & i_has_xattr_dir) == 0) {
nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
if (!REISERFS_SB(inode->i_sb)->xattr_root->d_inode)
nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
}
return nblocks;
}
static inline void reiserfs_init_xattr_rwsem(struct inode *inode)
{
init_rwsem(&REISERFS_I(inode)->i_xattr_sem);
}
#else
#define reiserfs_getxattr NULL
#define reiserfs_setxattr NULL
#define reiserfs_listxattr NULL
#define reiserfs_removexattr NULL
static inline void reiserfs_init_xattr_rwsem(struct inode *inode)
{
}
#endif /* CONFIG_REISERFS_FS_XATTR */
#ifndef CONFIG_REISERFS_FS_SECURITY
static inline int reiserfs_security_init(struct inode *dir,
struct inode *inode,
const struct qstr *qstr,
struct reiserfs_security_handle *sec)
{
return 0;
}
static inline int
reiserfs_security_write(struct reiserfs_transaction_handle *th,
struct inode *inode,
struct reiserfs_security_handle *sec)
{
return 0;
}
static inline void reiserfs_security_free(struct reiserfs_security_handle *sec)
{}
#endif
#endif /* __KERNEL__ */
#endif /* _LINUX_REISERFS_XATTR_H */