/**
* ea.c - Processing of EA's
*
* This module is part of ntfs-3g library
*
* Copyright (c) 2014 Jean-Pierre Andre
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (in the main directory of the NTFS-3G
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include "types.h"
#include "param.h"
#include "layout.h"
#include "attrib.h"
#include "index.h"
#include "dir.h"
#include "ea.h"
#include "misc.h"
#include "logging.h"
#include "xattrs.h"
/*
* Create a needed attribute (EA or EA_INFORMATION)
*
* Returns 0 if successful,
* -1 otherwise, with errno indicating why it failed.
*/
static int ntfs_need_ea(ntfs_inode *ni, ATTR_TYPES type, int size, int flags)
{
u8 dummy;
int res;
res = 0;
if (!ntfs_attr_exist(ni,type, AT_UNNAMED,0)) {
if (!(flags & XATTR_REPLACE)) {
/*
* no needed attribute : add one,
* apparently, this does not feed the new value in
* Note : NTFS version must be >= 3
*/
if (ni->vol->major_ver >= 3) {
res = ntfs_attr_add(ni, type,
AT_UNNAMED,0,&dummy,(s64)size);
if (!res) {
NInoFileNameSetDirty(ni);
}
NInoSetDirty(ni);
} else {
errno = EOPNOTSUPP;
res = -1;
}
} else {
errno = ENODATA;
res = -1;
}
}
return (res);
}
/*
* Restore the old EA_INFORMATION or delete the current one,
* when EA cannot be updated.
*
* As this is used in the context of some other error, the caller
* is responsible for returning the proper error, and errno is
* left unchanged.
* Only double errors are logged here.
*/
static void restore_ea_info(ntfs_attr *nai, const EA_INFORMATION *old_ea_info)
{
s64 written;
int olderrno;
olderrno = errno;
if (old_ea_info) {
written = ntfs_attr_pwrite(nai, 0, sizeof(EA_INFORMATION),
old_ea_info);
if ((size_t)written != sizeof(EA_INFORMATION)) {
ntfs_log_error("Could not restore the EA_INFORMATION,"
" possible inconsistency in inode %lld\n",
(long long)nai->ni->mft_no);
}
} else {
if (ntfs_attr_rm(nai)) {
ntfs_log_error("Could not delete the EA_INFORMATION,"
" possible inconsistency in inode %lld\n",
(long long)nai->ni->mft_no);
}
}
errno = olderrno;
}
/*
* Update both EA and EA_INFORMATION
*/
static int ntfs_update_ea(ntfs_inode *ni, const char *value, size_t size,
const EA_INFORMATION *ea_info,
const EA_INFORMATION *old_ea_info)
{
ntfs_attr *na;
ntfs_attr *nai;
int res;
res = 0;
nai = ntfs_attr_open(ni, AT_EA_INFORMATION, AT_UNNAMED, 0);
if (nai) {
na = ntfs_attr_open(ni, AT_EA, AT_UNNAMED, 0);
if (na) {
/*
* Set EA_INFORMATION first, it is easier to
* restore the old value, if setting EA fails.
*/
if (ntfs_attr_pwrite(nai, 0, sizeof(EA_INFORMATION),
ea_info)
!= (s64)sizeof(EA_INFORMATION)) {
res = -errno;
} else {
if (((na->data_size > (s64)size)
&& ntfs_attr_truncate(na, size))
|| (ntfs_attr_pwrite(na, 0, size, value)
!= (s64)size)) {
res = -errno;
if (old_ea_info)
restore_ea_info(nai,
old_ea_info);
}
}
ntfs_attr_close(na);
}
ntfs_attr_close(nai);
} else {
res = -errno;
}
return (res);
}
/*
* Return the existing EA
*
* The EA_INFORMATION is not examined and the consistency of the
* existing EA is not checked.
*
* If successful, the full attribute is returned unchanged
* and its size is returned.
* If the designated buffer is too small, the needed size is
* returned, and the buffer is left unchanged.
* If there is an error, a negative value is returned and errno
* is set according to the error.
*/
int ntfs_get_ntfs_ea(ntfs_inode *ni, char *value, size_t size)
{
s64 ea_size;
void *ea_buf;
int res = 0;
if (ntfs_attr_exist(ni, AT_EA, AT_UNNAMED, 0)) {
ea_buf = ntfs_attr_readall(ni, AT_EA, (ntfschar*)NULL, 0,
&ea_size);
if (ea_buf) {
if (value && (ea_size <= (s64)size))
memcpy(value, ea_buf, ea_size);
free(ea_buf);
res = ea_size;
} else {
ntfs_log_error("Failed to read EA from inode %lld\n",
(long long)ni->mft_no);
errno = ENODATA;
res = -errno;
}
} else {
errno = ENODATA;
res = -errno;
}
return (res);
}
/*
* Set a new EA, and set EA_INFORMATION accordingly
*
* This is roughly the same as ZwSetEaFile() on Windows, however
* the "offset to next" of the last EA should not be cleared.
*
* Consistency of the new EA is first checked.
*
* EA_INFORMATION is set first, and it is restored to its former
* state if setting EA fails.
*
* Returns 0 if successful
* a negative value if an error occurred.
*/
int ntfs_set_ntfs_ea(ntfs_inode *ni, const char *value, size_t size, int flags)
{
EA_INFORMATION ea_info;
EA_INFORMATION *old_ea_info;
s64 old_ea_size;
int res;
size_t offs;
size_t nextoffs;
BOOL ok;
int ea_count;
int ea_packed;
const EA_ATTR *p_ea;
res = -1;
if (value && (size > 0)) {
/* do consistency checks */
offs = 0;
ok = TRUE;
ea_count = 0;
ea_packed = 0;
nextoffs = 0;
while (ok && (offs < size)) {
p_ea = (const EA_ATTR*)&value[offs];
nextoffs = offs + le32_to_cpu(p_ea->next_entry_offset);
/* null offset to next not allowed */
ok = (nextoffs > offs)
&& (nextoffs <= size)
&& !(nextoffs & 3)
&& p_ea->name_length
/* zero sized value are allowed */
&& ((offs + offsetof(EA_ATTR,name)
+ p_ea->name_length + 1
+ le16_to_cpu(p_ea->value_length))
<= nextoffs)
&& ((offs + offsetof(EA_ATTR,name)
+ p_ea->name_length + 1
+ le16_to_cpu(p_ea->value_length))
>= (nextoffs - 3))
&& !p_ea->name[p_ea->name_length];
/* name not checked, as chkdsk accepts any chars */
if (ok) {
if (p_ea->flags & NEED_EA)
ea_count++;
/*
* Assume ea_packed includes :
* 4 bytes for header (flags and lengths)
* + name length + 1
* + value length
*/
ea_packed += 5 + p_ea->name_length
+ le16_to_cpu(p_ea->value_length);
offs = nextoffs;
}
}
/*
* EA and REPARSE_POINT exclude each other
* see http://msdn.microsoft.com/en-us/library/windows/desktop/aa364404(v=vs.85).aspx
* Also return EINVAL if REPARSE_POINT is present.
*/
if (ok
&& !ntfs_attr_exist(ni, AT_REPARSE_POINT, AT_UNNAMED,0)) {
ea_info.ea_length = cpu_to_le16(ea_packed);
ea_info.need_ea_count = cpu_to_le16(ea_count);
ea_info.ea_query_length = cpu_to_le32(nextoffs);
old_ea_size = 0;
old_ea_info = NULL;
/* Try to save the old EA_INFORMATION */
if (ntfs_attr_exist(ni, AT_EA_INFORMATION,
AT_UNNAMED, 0)) {
old_ea_info = ntfs_attr_readall(ni,
AT_EA_INFORMATION,
(ntfschar*)NULL, 0, &old_ea_size);
}
/*
* no EA or EA_INFORMATION : add them
*/
if (!ntfs_need_ea(ni, AT_EA_INFORMATION,
sizeof(EA_INFORMATION), flags)
&& !ntfs_need_ea(ni, AT_EA, 0, flags)) {
res = ntfs_update_ea(ni, value, size,
&ea_info, old_ea_info);
} else {
res = -errno;
}
if (old_ea_info)
free(old_ea_info);
} else {
errno = EINVAL;
res = -errno;
}
} else {
errno = EINVAL;
res = -errno;
}
return (res);
}
/*
* Remove the EA (including EA_INFORMATION)
*
* EA_INFORMATION is removed first, and it is restored to its former
* state if removing EA fails.
*
* Returns 0, or -1 if there is a problem
*/
int ntfs_remove_ntfs_ea(ntfs_inode *ni)
{
EA_INFORMATION *old_ea_info;
s64 old_ea_size;
int res;
ntfs_attr *na;
ntfs_attr *nai;
res = 0;
if (ni) {
/*
* open and delete the EA_INFORMATION and the EA
*/
nai = ntfs_attr_open(ni, AT_EA_INFORMATION, AT_UNNAMED, 0);
if (nai) {
na = ntfs_attr_open(ni, AT_EA, AT_UNNAMED, 0);
if (na) {
/* Try to save the old EA_INFORMATION */
old_ea_info = ntfs_attr_readall(ni,
AT_EA_INFORMATION,
(ntfschar*)NULL, 0, &old_ea_size);
res = ntfs_attr_rm(na);
NInoFileNameSetDirty(ni);
if (!res) {
res = ntfs_attr_rm(nai);
if (res && old_ea_info) {
/*
* Failed to remove the EA, try to
* restore the EA_INFORMATION
*/
restore_ea_info(nai,
old_ea_info);
}
} else {
ntfs_log_error("Failed to remove the"
" EA_INFORMATION from inode %lld\n",
(long long)ni->mft_no);
}
free(old_ea_info);
ntfs_attr_close(na);
} else {
/* EA_INFORMATION present, but no EA */
res = ntfs_attr_rm(nai);
NInoFileNameSetDirty(ni);
}
ntfs_attr_close(nai);
} else {
errno = ENODATA;
res = -1;
}
NInoSetDirty(ni);
} else {
errno = EINVAL;
res = -1;
}
return (res ? -1 : 0);
}
↑ V614 Uninitialized variable 'dummy' used. Consider checking the fifth actual argument of the 'ntfs_attr_add' function.