usbloadergx/source/libntfs/attrlist.c
2009-12-19 14:06:57 +00:00

315 lines
8.8 KiB
C

/**
* attrlist.c - Attribute list attribute handling code. Originated from the Linux-NTFS
* project.
*
* Copyright (c) 2004-2005 Anton Altaparmakov
* Copyright (c) 2004-2005 Yura Pakhuchiy
* Copyright (c) 2006 Szabolcs Szakacsits
*
* 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_STRING_H
#include <string.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include "types.h"
#include "layout.h"
#include "attrib.h"
#include "attrlist.h"
#include "debug.h"
#include "unistr.h"
#include "logging.h"
#include "misc.h"
/**
* ntfs_attrlist_need - check whether inode need attribute list
* @ni: opened ntfs inode for which perform check
*
* Check whether all are attributes belong to one MFT record, in that case
* attribute list is not needed.
*
* Return 1 if inode need attribute list, 0 if not, -1 on error with errno set
* to the error code. If function succeed errno set to 0. The following error
* codes are defined:
* EINVAL - Invalid arguments passed to function or attribute haven't got
* attribute list.
*/
int ntfs_attrlist_need(ntfs_inode *ni)
{
ATTR_LIST_ENTRY *ale;
if (!ni) {
ntfs_log_trace("Invalid arguments.\n");
errno = EINVAL;
return -1;
}
ntfs_log_trace("Entering for inode 0x%llx.\n", (long long) ni->mft_no);
if (!NInoAttrList(ni)) {
ntfs_log_trace("Inode haven't got attribute list.\n");
errno = EINVAL;
return -1;
}
if (!ni->attr_list) {
ntfs_log_trace("Corrupt in-memory struct.\n");
errno = EINVAL;
return -1;
}
errno = 0;
ale = (ATTR_LIST_ENTRY *)ni->attr_list;
while ((u8*)ale < ni->attr_list + ni->attr_list_size) {
if (MREF_LE(ale->mft_reference) != ni->mft_no)
return 1;
ale = (ATTR_LIST_ENTRY *)((u8*)ale + le16_to_cpu(ale->length));
}
return 0;
}
/**
* ntfs_attrlist_entry_add - add an attribute list attribute entry
* @ni: opened ntfs inode, which contains that attribute
* @attr: attribute record to add to attribute list
*
* Return 0 on success and -1 on error with errno set to the error code. The
* following error codes are defined:
* EINVAL - Invalid arguments passed to function.
* ENOMEM - Not enough memory to allocate necessary buffers.
* EIO - I/O error occurred or damaged filesystem.
* EEXIST - Such attribute already present in attribute list.
*/
int ntfs_attrlist_entry_add(ntfs_inode *ni, ATTR_RECORD *attr)
{
ATTR_LIST_ENTRY *ale;
MFT_REF mref;
ntfs_attr *na = NULL;
ntfs_attr_search_ctx *ctx;
u8 *new_al;
int entry_len, entry_offset, err;
ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n",
(long long) ni->mft_no,
(unsigned) le32_to_cpu(attr->type));
if (!ni || !attr) {
ntfs_log_trace("Invalid arguments.\n");
errno = EINVAL;
return -1;
}
mref = MK_LE_MREF(ni->mft_no, le16_to_cpu(ni->mrec->sequence_number));
if (ni->nr_extents == -1)
ni = ni->base_ni;
if (!NInoAttrList(ni)) {
ntfs_log_trace("Attribute list isn't present.\n");
errno = ENOENT;
return -1;
}
/* Determine size and allocate memory for new attribute list. */
entry_len = (sizeof(ATTR_LIST_ENTRY) + sizeof(ntfschar) *
attr->name_length + 7) & ~7;
new_al = ntfs_calloc(ni->attr_list_size + entry_len);
if (!new_al)
return -1;
/* Find place for the new entry. */
ctx = ntfs_attr_get_search_ctx(ni, NULL);
if (!ctx) {
err = errno;
goto err_out;
}
if (!ntfs_attr_lookup(attr->type, (attr->name_length) ? (ntfschar*)
((u8*)attr + le16_to_cpu(attr->name_offset)) :
AT_UNNAMED, attr->name_length, CASE_SENSITIVE,
(attr->non_resident) ? le64_to_cpu(attr->lowest_vcn) :
0, (attr->non_resident) ? NULL : ((u8*)attr +
le16_to_cpu(attr->value_offset)), (attr->non_resident) ?
0 : le32_to_cpu(attr->value_length), ctx)) {
/* Found some extent, check it to be before new extent. */
if (ctx->al_entry->lowest_vcn == attr->lowest_vcn) {
err = EEXIST;
ntfs_log_trace("Such attribute already present in the "
"attribute list.\n");
ntfs_attr_put_search_ctx(ctx);
goto err_out;
}
/* Add new entry after this extent. */
ale = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry +
le16_to_cpu(ctx->al_entry->length));
} else {
/* Check for real errors. */
if (errno != ENOENT) {
err = errno;
ntfs_log_trace("Attribute lookup failed.\n");
ntfs_attr_put_search_ctx(ctx);
goto err_out;
}
/* No previous extents found. */
ale = ctx->al_entry;
}
/* Don't need it anymore, @ctx->al_entry points to @ni->attr_list. */
ntfs_attr_put_search_ctx(ctx);
/* Determine new entry offset. */
entry_offset = ((u8 *)ale - ni->attr_list);
/* Set pointer to new entry. */
ale = (ATTR_LIST_ENTRY *)(new_al + entry_offset);
/* Zero it to fix valgrind warning. */
memset(ale, 0, entry_len);
/* Form new entry. */
ale->type = attr->type;
ale->length = cpu_to_le16(entry_len);
ale->name_length = attr->name_length;
ale->name_offset = offsetof(ATTR_LIST_ENTRY, name);
if (attr->non_resident)
ale->lowest_vcn = attr->lowest_vcn;
else
ale->lowest_vcn = 0;
ale->mft_reference = mref;
ale->instance = attr->instance;
memcpy(ale->name, (u8 *)attr + le16_to_cpu(attr->name_offset),
attr->name_length * sizeof(ntfschar));
/* Resize $ATTRIBUTE_LIST to new length. */
na = ntfs_attr_open(ni, AT_ATTRIBUTE_LIST, AT_UNNAMED, 0);
if (!na) {
err = errno;
ntfs_log_trace("Failed to open $ATTRIBUTE_LIST attribute.\n");
goto err_out;
}
if (ntfs_attr_truncate(na, ni->attr_list_size + entry_len)) {
err = errno;
ntfs_log_trace("$ATTRIBUTE_LIST resize failed.\n");
goto err_out;
}
/* Copy entries from old attribute list to new. */
memcpy(new_al, ni->attr_list, entry_offset);
memcpy(new_al + entry_offset + entry_len, ni->attr_list +
entry_offset, ni->attr_list_size - entry_offset);
/* Set new runlist. */
free(ni->attr_list);
ni->attr_list = new_al;
ni->attr_list_size = ni->attr_list_size + entry_len;
NInoAttrListSetDirty(ni);
/* Done! */
ntfs_attr_close(na);
return 0;
err_out:
if (na)
ntfs_attr_close(na);
free(new_al);
errno = err;
return -1;
}
/**
* ntfs_attrlist_entry_rm - remove an attribute list attribute entry
* @ctx: attribute search context describing the attribute list entry
*
* Remove the attribute list entry @ctx->al_entry from the attribute list.
*
* Return 0 on success and -1 on error with errno set to the error code.
*/
int ntfs_attrlist_entry_rm(ntfs_attr_search_ctx *ctx)
{
u8 *new_al;
int new_al_len;
ntfs_inode *base_ni;
ntfs_attr *na;
ATTR_LIST_ENTRY *ale;
int err;
if (!ctx || !ctx->ntfs_ino || !ctx->al_entry) {
ntfs_log_trace("Invalid arguments.\n");
errno = EINVAL;
return -1;
}
if (ctx->base_ntfs_ino)
base_ni = ctx->base_ntfs_ino;
else
base_ni = ctx->ntfs_ino;
ale = ctx->al_entry;
ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x, lowest_vcn %lld.\n",
(long long) ctx->ntfs_ino->mft_no,
(unsigned) le32_to_cpu(ctx->al_entry->type),
(long long) le64_to_cpu(ctx->al_entry->lowest_vcn));
if (!NInoAttrList(base_ni)) {
ntfs_log_trace("Attribute list isn't present.\n");
errno = ENOENT;
return -1;
}
/* Allocate memory for new attribute list. */
new_al_len = base_ni->attr_list_size - le16_to_cpu(ale->length);
new_al = ntfs_calloc(new_al_len);
if (!new_al)
return -1;
/* Reisze $ATTRIBUTE_LIST to new length. */
na = ntfs_attr_open(base_ni, AT_ATTRIBUTE_LIST, AT_UNNAMED, 0);
if (!na) {
err = errno;
ntfs_log_trace("Failed to open $ATTRIBUTE_LIST attribute.\n");
goto err_out;
}
if (ntfs_attr_truncate(na, new_al_len)) {
err = errno;
ntfs_log_trace("$ATTRIBUTE_LIST resize failed.\n");
goto err_out;
}
/* Copy entries from old attribute list to new. */
memcpy(new_al, base_ni->attr_list, (u8*)ale - base_ni->attr_list);
memcpy(new_al + ((u8*)ale - base_ni->attr_list), (u8*)ale + le16_to_cpu(
ale->length), new_al_len - ((u8*)ale - base_ni->attr_list));
/* Set new runlist. */
free(base_ni->attr_list);
base_ni->attr_list = new_al;
base_ni->attr_list_size = new_al_len;
NInoAttrListSetDirty(base_ni);
/* Done! */
ntfs_attr_close(na);
return 0;
err_out:
if (na)
ntfs_attr_close(na);
free(new_al);
errno = err;
return -1;
}