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ntfs-3g/libntfs-3g/index.c
Jean-Pierre André 094f9b3f2d Fixed a minor endianness ajustment bug 
The endianness ajustment was the wrong one though it did the correct thing.
2021-01-26 10:06:18 +01:00

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/**
* index.c - NTFS index handling. Originated from the Linux-NTFS project.
*
* Copyright (c) 2004-2005 Anton Altaparmakov
* Copyright (c) 2004-2005 Richard Russon
* Copyright (c) 2005-2006 Yura Pakhuchiy
* Copyright (c) 2005-2008 Szabolcs Szakacsits
* Copyright (c) 2007-2020 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_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include "attrib.h"
#include "debug.h"
#include "index.h"
#include "collate.h"
#include "mst.h"
#include "dir.h"
#include "logging.h"
#include "bitmap.h"
#include "reparse.h"
#include "misc.h"
/**
* ntfs_index_entry_mark_dirty - mark an index entry dirty
* @ictx: ntfs index context describing the index entry
*
* Mark the index entry described by the index entry context @ictx dirty.
*
* If the index entry is in the index root attribute, simply mark the inode
* containing the index root attribute dirty. This ensures the mftrecord, and
* hence the index root attribute, will be written out to disk later.
*
* If the index entry is in an index block belonging to the index allocation
* attribute, set ib_dirty to TRUE, thus index block will be updated during
* ntfs_index_ctx_put.
*/
void ntfs_index_entry_mark_dirty(ntfs_index_context *ictx)
{
if (ictx->is_in_root)
ntfs_inode_mark_dirty(ictx->actx->ntfs_ino);
else
ictx->ib_dirty = TRUE;
}
static s64 ntfs_ib_vcn_to_pos(ntfs_index_context *icx, VCN vcn)
{
return vcn << icx->vcn_size_bits;
}
static VCN ntfs_ib_pos_to_vcn(ntfs_index_context *icx, s64 pos)
{
return pos >> icx->vcn_size_bits;
}
static int ntfs_ib_write(ntfs_index_context *icx, INDEX_BLOCK *ib)
{
s64 ret, vcn = sle64_to_cpu(ib->index_block_vcn);
ntfs_log_trace("vcn: %lld\n", (long long)vcn);
ret = ntfs_attr_mst_pwrite(icx->ia_na, ntfs_ib_vcn_to_pos(icx, vcn),
1, icx->block_size, ib);
if (ret != 1) {
ntfs_log_perror("Failed to write index block %lld, inode %llu",
(long long)vcn, (unsigned long long)icx->ni->mft_no);
return STATUS_ERROR;
}
return STATUS_OK;
}
static int ntfs_icx_ib_write(ntfs_index_context *icx)
{
if (ntfs_ib_write(icx, icx->ib))
return STATUS_ERROR;
icx->ib_dirty = FALSE;
return STATUS_OK;
}
/**
* ntfs_index_ctx_get - allocate and initialize a new index context
* @ni: ntfs inode with which to initialize the context
* @name: name of the which context describes
* @name_len: length of the index name
*
* Allocate a new index context, initialize it with @ni and return it.
* Return NULL if allocation failed.
*/
ntfs_index_context *ntfs_index_ctx_get(ntfs_inode *ni,
ntfschar *name, u32 name_len)
{
ntfs_index_context *icx;
ntfs_log_trace("Entering\n");
if (!ni) {
errno = EINVAL;
return NULL;
}
if (ni->nr_extents == -1)
ni = ni->base_ni;
icx = ntfs_calloc(sizeof(ntfs_index_context));
if (icx)
*icx = (ntfs_index_context) {
.ni = ni,
.name = name,
.name_len = name_len,
};
return icx;
}
static void ntfs_index_ctx_free(ntfs_index_context *icx)
{
ntfs_log_trace("Entering\n");
if (!icx->bad_index && !icx->entry)
return;
if (icx->actx)
ntfs_attr_put_search_ctx(icx->actx);
if (!icx->is_in_root) {
if (icx->ib_dirty) {
/* FIXME: Error handling!!! */
ntfs_ib_write(icx, icx->ib);
}
free(icx->ib);
}
ntfs_attr_close(icx->ia_na);
}
/**
* ntfs_index_ctx_put - release an index context
* @icx: index context to free
*
* Release the index context @icx, releasing all associated resources.
*/
void ntfs_index_ctx_put(ntfs_index_context *icx)
{
ntfs_index_ctx_free(icx);
free(icx);
}
/**
* ntfs_index_ctx_reinit - reinitialize an index context
* @icx: index context to reinitialize
*
* Reinitialize the index context @icx so it can be used for ntfs_index_lookup.
*/
void ntfs_index_ctx_reinit(ntfs_index_context *icx)
{
ntfs_log_trace("Entering\n");
ntfs_index_ctx_free(icx);
*icx = (ntfs_index_context) {
.ni = icx->ni,
.name = icx->name,
.name_len = icx->name_len,
};
}
static leVCN *ntfs_ie_get_vcn_addr(INDEX_ENTRY *ie)
{
return (leVCN *)((u8 *)ie + le16_to_cpu(ie->length) - sizeof(leVCN));
}
/**
* Get the subnode vcn to which the index entry refers.
*/
VCN ntfs_ie_get_vcn(INDEX_ENTRY *ie)
{
return sle64_to_cpup(ntfs_ie_get_vcn_addr(ie));
}
static INDEX_ENTRY *ntfs_ie_get_first(INDEX_HEADER *ih)
{
return (INDEX_ENTRY *)((u8 *)ih + le32_to_cpu(ih->entries_offset));
}
static INDEX_ENTRY *ntfs_ie_get_next(INDEX_ENTRY *ie)
{
return (INDEX_ENTRY *)((char *)ie + le16_to_cpu(ie->length));
}
static u8 *ntfs_ie_get_end(INDEX_HEADER *ih)
{
/* FIXME: check if it isn't overflowing the index block size */
return (u8 *)ih + le32_to_cpu(ih->index_length);
}
static int ntfs_ie_end(INDEX_ENTRY *ie)
{
return ie->ie_flags & INDEX_ENTRY_END || !ie->length;
}
/**
* Find the last entry in the index block
*/
static INDEX_ENTRY *ntfs_ie_get_last(INDEX_ENTRY *ie, char *ies_end)
{
ntfs_log_trace("Entering\n");
while ((char *)ie < ies_end && !ntfs_ie_end(ie))
ie = ntfs_ie_get_next(ie);
return ie;
}
static INDEX_ENTRY *ntfs_ie_get_by_pos(INDEX_HEADER *ih, int pos)
{
INDEX_ENTRY *ie;
ntfs_log_trace("pos: %d\n", pos);
ie = ntfs_ie_get_first(ih);
while (pos-- > 0)
ie = ntfs_ie_get_next(ie);
return ie;
}
static INDEX_ENTRY *ntfs_ie_prev(INDEX_HEADER *ih, INDEX_ENTRY *ie)
{
INDEX_ENTRY *ie_prev = NULL;
INDEX_ENTRY *tmp;
ntfs_log_trace("Entering\n");
tmp = ntfs_ie_get_first(ih);
while (tmp != ie) {
ie_prev = tmp;
tmp = ntfs_ie_get_next(tmp);
}
return ie_prev;
}
char *ntfs_ie_filename_get(INDEX_ENTRY *ie)
{
FILE_NAME_ATTR *fn;
fn = (FILE_NAME_ATTR *)&ie->key;
return ntfs_attr_name_get(fn->file_name, fn->file_name_length);
}
void ntfs_ie_filename_dump(INDEX_ENTRY *ie)
{
char *s;
s = ntfs_ie_filename_get(ie);
ntfs_log_debug("'%s' ", s);
ntfs_attr_name_free(&s);
}
void ntfs_ih_filename_dump(INDEX_HEADER *ih)
{
INDEX_ENTRY *ie;
ntfs_log_trace("Entering\n");
ie = ntfs_ie_get_first(ih);
while (!ntfs_ie_end(ie)) {
ntfs_ie_filename_dump(ie);
ie = ntfs_ie_get_next(ie);
}
}
static int ntfs_ih_numof_entries(INDEX_HEADER *ih)
{
int n;
INDEX_ENTRY *ie;
u8 *end;
ntfs_log_trace("Entering\n");
end = ntfs_ie_get_end(ih);
ie = ntfs_ie_get_first(ih);
for (n = 0; !ntfs_ie_end(ie) && (u8 *)ie < end; n++)
ie = ntfs_ie_get_next(ie);
return n;
}
static int ntfs_ih_one_entry(INDEX_HEADER *ih)
{
return (ntfs_ih_numof_entries(ih) == 1);
}
static int ntfs_ih_zero_entry(INDEX_HEADER *ih)
{
return (ntfs_ih_numof_entries(ih) == 0);
}
static void ntfs_ie_delete(INDEX_HEADER *ih, INDEX_ENTRY *ie)
{
u32 new_size;
ntfs_log_trace("Entering\n");
new_size = le32_to_cpu(ih->index_length) - le16_to_cpu(ie->length);
ih->index_length = cpu_to_le32(new_size);
memmove(ie, (u8 *)ie + le16_to_cpu(ie->length),
new_size - ((u8 *)ie - (u8 *)ih));
}
static void ntfs_ie_set_vcn(INDEX_ENTRY *ie, VCN vcn)
{
*ntfs_ie_get_vcn_addr(ie) = cpu_to_sle64(vcn);
}
/**
* Insert @ie index entry at @pos entry. Used @ih values should be ok already.
*/
static void ntfs_ie_insert(INDEX_HEADER *ih, INDEX_ENTRY *ie, INDEX_ENTRY *pos)
{
int ie_size = le16_to_cpu(ie->length);
ntfs_log_trace("Entering\n");
ih->index_length = cpu_to_le32(le32_to_cpu(ih->index_length) + ie_size);
memmove((u8 *)pos + ie_size, pos,
le32_to_cpu(ih->index_length) - ((u8 *)pos - (u8 *)ih) - ie_size);
memcpy(pos, ie, ie_size);
}
static INDEX_ENTRY *ntfs_ie_dup(INDEX_ENTRY *ie)
{
INDEX_ENTRY *dup;
ntfs_log_trace("Entering\n");
dup = ntfs_malloc(le16_to_cpu(ie->length));
if (dup)
memcpy(dup, ie, le16_to_cpu(ie->length));
return dup;
}
static INDEX_ENTRY *ntfs_ie_dup_novcn(INDEX_ENTRY *ie)
{
INDEX_ENTRY *dup;
int size = le16_to_cpu(ie->length);
ntfs_log_trace("Entering\n");
if (ie->ie_flags & INDEX_ENTRY_NODE)
size -= sizeof(VCN);
dup = ntfs_malloc(size);
if (dup) {
memcpy(dup, ie, size);
dup->ie_flags &= ~INDEX_ENTRY_NODE;
dup->length = cpu_to_le16(size);
}
return dup;
}
static int ntfs_ia_check(ntfs_index_context *icx, INDEX_BLOCK *ib, VCN vcn)
{
u32 ib_size = (unsigned)le32_to_cpu(ib->index.allocated_size) + 0x18;
ntfs_log_trace("Entering\n");
if (!ntfs_is_indx_record(ib->magic)) {
ntfs_log_error("Corrupt index block signature: vcn %lld inode "
"%llu\n", (long long)vcn,
(unsigned long long)icx->ni->mft_no);
return -1;
}
if (sle64_to_cpu(ib->index_block_vcn) != vcn) {
ntfs_log_error("Corrupt index block: VCN (%lld) is different "
"from expected VCN (%lld) in inode %llu\n",
(long long)sle64_to_cpu(ib->index_block_vcn),
(long long)vcn,
(unsigned long long)icx->ni->mft_no);
return -1;
}
if (ib_size != icx->block_size) {
ntfs_log_error("Corrupt index block : VCN (%lld) of inode %llu "
"has a size (%u) differing from the index "
"specified size (%u)\n", (long long)vcn,
(unsigned long long)icx->ni->mft_no, ib_size,
icx->block_size);
return -1;
}
return 0;
}
static INDEX_ROOT *ntfs_ir_lookup(ntfs_inode *ni, ntfschar *name,
u32 name_len, ntfs_attr_search_ctx **ctx)
{
ATTR_RECORD *a;
INDEX_ROOT *ir = NULL;
ntfs_log_trace("Entering\n");
*ctx = ntfs_attr_get_search_ctx(ni, NULL);
if (!*ctx)
return NULL;
if (ntfs_attr_lookup(AT_INDEX_ROOT, name, name_len, CASE_SENSITIVE,
0, NULL, 0, *ctx)) {
ntfs_log_perror("Failed to lookup $INDEX_ROOT");
goto err_out;
}
a = (*ctx)->attr;
if (a->non_resident) {
errno = EINVAL;
ntfs_log_perror("Non-resident $INDEX_ROOT detected");
goto err_out;
}
ir = (INDEX_ROOT *)((char *)a + le16_to_cpu(a->value_offset));
err_out:
if (!ir) {
ntfs_attr_put_search_ctx(*ctx);
*ctx = NULL;
}
return ir;
}
static INDEX_ROOT *ntfs_ir_lookup2(ntfs_inode *ni, ntfschar *name, u32 len)
{
ntfs_attr_search_ctx *ctx;
INDEX_ROOT *ir;
ir = ntfs_ir_lookup(ni, name, len, &ctx);
if (ir)
ntfs_attr_put_search_ctx(ctx);
return ir;
}
/**
* Find a key in the index block.
*
* Return values:
* STATUS_OK with errno set to ESUCCESS if we know for sure that the
* entry exists and @ie_out points to this entry.
* STATUS_NOT_FOUND with errno set to ENOENT if we know for sure the
* entry doesn't exist and @ie_out is the insertion point.
* STATUS_KEEP_SEARCHING if we can't answer the above question and
* @vcn will contain the node index block.
* STATUS_ERROR with errno set if on unexpected error during lookup.
*/
static int ntfs_ie_lookup(const void *key, const int key_len,
ntfs_index_context *icx, INDEX_HEADER *ih,
VCN *vcn, INDEX_ENTRY **ie_out)
{
INDEX_ENTRY *ie;
u8 *index_end;
int rc, item = 0;
ntfs_log_trace("Entering\n");
index_end = ntfs_ie_get_end(ih);
/*
* Loop until we exceed valid memory (corruption case) or until we
* reach the last entry.
*/
for (ie = ntfs_ie_get_first(ih); ; ie = ntfs_ie_get_next(ie)) {
/* Bounds checks. */
if ((u8 *)ie + sizeof(INDEX_ENTRY_HEADER) > index_end ||
(u8 *)ie + le16_to_cpu(ie->length) > index_end) {
errno = ERANGE;
ntfs_log_error("Index entry out of bounds in inode "
"%llu.\n",
(unsigned long long)icx->ni->mft_no);
return STATUS_ERROR;
}
/*
* The last entry cannot contain a key. It can however contain
* a pointer to a child node in the B+tree so we just break out.
*/
if (ntfs_ie_end(ie))
break;
/*
* Not a perfect match, need to do full blown collation so we
* know which way in the B+tree we have to go.
*/
if (!icx->collate) {
ntfs_log_error("Collation function not defined\n");
errno = EOPNOTSUPP;
return STATUS_ERROR;
}
rc = icx->collate(icx->ni->vol, key, key_len,
&ie->key, le16_to_cpu(ie->key_length));
if (rc == NTFS_COLLATION_ERROR) {
ntfs_log_error("Collation error. Perhaps a filename "
"contains invalid characters?\n");
errno = ERANGE;
return STATUS_ERROR;
}
/*
* If @key collates before the key of the current entry, there
* is definitely no such key in this index but we might need to
* descend into the B+tree so we just break out of the loop.
*/
if (rc == -1)
break;
if (!rc) {
*ie_out = ie;
errno = 0;
icx->parent_pos[icx->pindex] = item;
return STATUS_OK;
}
item++;
}
/*
* We have finished with this index block without success. Check for the
* presence of a child node and if not present return with errno ENOENT,
* otherwise we will keep searching in another index block.
*/
if (!(ie->ie_flags & INDEX_ENTRY_NODE)) {
ntfs_log_debug("Index entry wasn't found.\n");
*ie_out = ie;
errno = ENOENT;
return STATUS_NOT_FOUND;
}
/* Get the starting vcn of the index_block holding the child node. */
*vcn = ntfs_ie_get_vcn(ie);
if (*vcn < 0) {
errno = EINVAL;
ntfs_log_perror("Negative vcn in inode %llu",
(unsigned long long)icx->ni->mft_no);
return STATUS_ERROR;
}
ntfs_log_trace("Parent entry number %d\n", item);
icx->parent_pos[icx->pindex] = item;
return STATUS_KEEP_SEARCHING;
}
static ntfs_attr *ntfs_ia_open(ntfs_index_context *icx, ntfs_inode *ni)
{
ntfs_attr *na;
na = ntfs_attr_open(ni, AT_INDEX_ALLOCATION, icx->name, icx->name_len);
if (!na) {
ntfs_log_perror("Failed to open index allocation of inode "
"%llu", (unsigned long long)ni->mft_no);
return NULL;
}
return na;
}
static int ntfs_ib_read(ntfs_index_context *icx, VCN vcn, INDEX_BLOCK *dst)
{
s64 pos, ret;
ntfs_log_trace("vcn: %lld\n", (long long)vcn);
pos = ntfs_ib_vcn_to_pos(icx, vcn);
ret = ntfs_attr_mst_pread(icx->ia_na, pos, 1, icx->block_size, (u8 *)dst);
if (ret != 1) {
if (ret == -1)
ntfs_log_perror("Failed to read index block");
else
ntfs_log_error("Failed to read full index block at "
"%lld\n", (long long)pos);
return -1;
}
if (ntfs_ia_check(icx, dst, vcn))
return -1;
return 0;
}
static int ntfs_icx_parent_inc(ntfs_index_context *icx)
{
icx->pindex++;
if (icx->pindex >= MAX_PARENT_VCN) {
errno = EOPNOTSUPP;
ntfs_log_perror("Index is over %d level deep", MAX_PARENT_VCN);
return STATUS_ERROR;
}
return STATUS_OK;
}
static int ntfs_icx_parent_dec(ntfs_index_context *icx)
{
icx->pindex--;
if (icx->pindex < 0) {
errno = EINVAL;
ntfs_log_perror("Corrupt index pointer (%d)", icx->pindex);
return STATUS_ERROR;
}
return STATUS_OK;
}
/**
* ntfs_index_lookup - find a key in an index and return its index entry
* @key: [IN] key for which to search in the index
* @key_len: [IN] length of @key in bytes
* @icx: [IN/OUT] context describing the index and the returned entry
*
* Before calling ntfs_index_lookup(), @icx must have been obtained from a
* call to ntfs_index_ctx_get().
*
* Look for the @key in the index specified by the index lookup context @icx.
* ntfs_index_lookup() walks the contents of the index looking for the @key.
*
* If the @key is found in the index, 0 is returned and @icx is setup to
* describe the index entry containing the matching @key. @icx->entry is the
* index entry and @icx->data and @icx->data_len are the index entry data and
* its length in bytes, respectively.
*
* If the @key is not found in the index, -1 is returned, errno = ENOENT and
* @icx is setup to describe the index entry whose key collates immediately
* after the search @key, i.e. this is the position in the index at which
* an index entry with a key of @key would need to be inserted.
*
* If an error occurs return -1, set errno to error code and @icx is left
* untouched.
*
* When finished with the entry and its data, call ntfs_index_ctx_put() to free
* the context and other associated resources.
*
* If the index entry was modified, call ntfs_index_entry_mark_dirty() before
* the call to ntfs_index_ctx_put() to ensure that the changes are written
* to disk.
*/
int ntfs_index_lookup(const void *key, const int key_len, ntfs_index_context *icx)
{
VCN old_vcn, vcn;
ntfs_inode *ni = icx->ni;
INDEX_ROOT *ir;
INDEX_ENTRY *ie;
INDEX_BLOCK *ib = NULL;
int ret, err = 0;
ntfs_log_trace("Entering\n");
if (!key || key_len <= 0) {
errno = EINVAL;
ntfs_log_perror("key: %p key_len: %d", key, key_len);
return -1;
}
ir = ntfs_ir_lookup(ni, icx->name, icx->name_len, &icx->actx);
if (!ir) {
if (errno == ENOENT)
errno = EIO;
return -1;
}
icx->block_size = le32_to_cpu(ir->index_block_size);
if (icx->block_size < NTFS_BLOCK_SIZE) {
errno = EINVAL;
ntfs_log_perror("Index block size (%d) is smaller than the "
"sector size (%d)", icx->block_size, NTFS_BLOCK_SIZE);
goto err_out;
}
if (ni->vol->cluster_size <= icx->block_size)
icx->vcn_size_bits = ni->vol->cluster_size_bits;
else
icx->vcn_size_bits = NTFS_BLOCK_SIZE_BITS;
/* get the appropriate collation function */
icx->collate = ntfs_get_collate_function(ir->collation_rule);
if (!icx->collate) {
err = errno = EOPNOTSUPP;
ntfs_log_perror("Unknown collation rule 0x%x",
(unsigned)le32_to_cpu(ir->collation_rule));
goto err_out;
}
old_vcn = VCN_INDEX_ROOT_PARENT;
/*
* FIXME: check for both ir and ib that the first index entry is
* within the index block.
*/
ret = ntfs_ie_lookup(key, key_len, icx, &ir->index, &vcn, &ie);
if (ret == STATUS_ERROR) {
err = errno;
goto err_lookup;
}
icx->ir = ir;
if (ret != STATUS_KEEP_SEARCHING) {
/* STATUS_OK or STATUS_NOT_FOUND */
err = errno;
icx->is_in_root = TRUE;
icx->parent_vcn[icx->pindex] = old_vcn;
goto done;
}
/* Child node present, descend into it. */
icx->ia_na = ntfs_ia_open(icx, ni);
if (!icx->ia_na)
goto err_out;
ib = ntfs_malloc(icx->block_size);
if (!ib) {
err = errno;
goto err_out;
}
descend_into_child_node:
icx->parent_vcn[icx->pindex] = old_vcn;
if (ntfs_icx_parent_inc(icx)) {
err = errno;
goto err_out;
}
old_vcn = vcn;
ntfs_log_debug("Descend into node with VCN %lld\n", (long long)vcn);
if (ntfs_ib_read(icx, vcn, ib))
goto err_out;
ret = ntfs_ie_lookup(key, key_len, icx, &ib->index, &vcn, &ie);
if (ret != STATUS_KEEP_SEARCHING) {
err = errno;
if (ret == STATUS_ERROR)
goto err_out;
/* STATUS_OK or STATUS_NOT_FOUND */
icx->is_in_root = FALSE;
icx->ib = ib;
icx->parent_vcn[icx->pindex] = vcn;
goto done;
}
if ((ib->index.ih_flags & NODE_MASK) == LEAF_NODE) {
ntfs_log_error("Index entry with child node found in a leaf "
"node in inode 0x%llx.\n",
(unsigned long long)ni->mft_no);
goto err_out;
}
goto descend_into_child_node;
err_out:
icx->bad_index = TRUE; /* Force icx->* to be freed */
err_lookup:
free(ib);
if (!err)
err = EIO;
errno = err;
return -1;
done:
icx->entry = ie;
icx->data = (u8 *)ie + offsetof(INDEX_ENTRY, key);
icx->data_len = le16_to_cpu(ie->key_length);
ntfs_log_trace("Done.\n");
if (err) {
errno = err;
return -1;
}
return 0;
}
static INDEX_BLOCK *ntfs_ib_alloc(VCN ib_vcn, u32 ib_size,
INDEX_HEADER_FLAGS node_type)
{
INDEX_BLOCK *ib;
int ih_size = sizeof(INDEX_HEADER);
ntfs_log_trace("ib_vcn: %lld ib_size: %u\n", (long long)ib_vcn, ib_size);
ib = ntfs_calloc(ib_size);
if (!ib)
return NULL;
ib->magic = magic_INDX;
ib->usa_ofs = const_cpu_to_le16(sizeof(INDEX_BLOCK));
ib->usa_count = cpu_to_le16(ib_size / NTFS_BLOCK_SIZE + 1);
/* Set USN to 1 */
*(le16 *)((char *)ib + le16_to_cpu(ib->usa_ofs)) = const_cpu_to_le16(1);
ib->lsn = const_cpu_to_sle64(0);
ib->index_block_vcn = cpu_to_sle64(ib_vcn);
ib->index.entries_offset = cpu_to_le32((ih_size +
le16_to_cpu(ib->usa_count) * 2 + 7) & ~7);
ib->index.index_length = const_cpu_to_le32(0);
ib->index.allocated_size = cpu_to_le32(ib_size -
(sizeof(INDEX_BLOCK) - ih_size));
ib->index.ih_flags = node_type;
return ib;
}
/**
* Find the median by going through all the entries
*/
static INDEX_ENTRY *ntfs_ie_get_median(INDEX_HEADER *ih)
{
INDEX_ENTRY *ie, *ie_start;
u8 *ie_end;
int i = 0, median;
ntfs_log_trace("Entering\n");
ie = ie_start = ntfs_ie_get_first(ih);
ie_end = (u8 *)ntfs_ie_get_end(ih);
while ((u8 *)ie < ie_end && !ntfs_ie_end(ie)) {
ie = ntfs_ie_get_next(ie);
i++;
}
/*
* NOTE: this could be also the entry at the half of the index block.
*/
median = i / 2 - 1;
ntfs_log_trace("Entries: %d median: %d\n", i, median);
for (i = 0, ie = ie_start; i <= median; i++)
ie = ntfs_ie_get_next(ie);
return ie;
}
static s64 ntfs_ibm_vcn_to_pos(ntfs_index_context *icx, VCN vcn)
{
return ntfs_ib_vcn_to_pos(icx, vcn) / icx->block_size;
}
static s64 ntfs_ibm_pos_to_vcn(ntfs_index_context *icx, s64 pos)
{
return ntfs_ib_pos_to_vcn(icx, pos * icx->block_size);
}
static int ntfs_ibm_add(ntfs_index_context *icx)
{
u8 bmp[8];
ntfs_log_trace("Entering\n");
if (ntfs_attr_exist(icx->ni, AT_BITMAP, icx->name, icx->name_len))
return STATUS_OK;
/*
* AT_BITMAP must be at least 8 bytes.
*/
memset(bmp, 0, sizeof(bmp));
if (ntfs_attr_add(icx->ni, AT_BITMAP, icx->name, icx->name_len,
bmp, sizeof(bmp))) {
ntfs_log_perror("Failed to add AT_BITMAP");
return STATUS_ERROR;
}
return STATUS_OK;
}
static int ntfs_ibm_modify(ntfs_index_context *icx, VCN vcn, int set)
{
u8 byte;
s64 pos = ntfs_ibm_vcn_to_pos(icx, vcn);
u32 bpos = pos / 8;
u32 bit = 1 << (pos % 8);
ntfs_attr *na;
int ret = STATUS_ERROR;
ntfs_log_trace("%s vcn: %lld\n", set ? "set" : "clear", (long long)vcn);
na = ntfs_attr_open(icx->ni, AT_BITMAP, icx->name, icx->name_len);
if (!na) {
ntfs_log_perror("Failed to open $BITMAP attribute");
return -1;
}
if (set) {
if (na->data_size < bpos + 1) {
if (ntfs_attr_truncate(na, (na->data_size + 8) & ~7)) {
ntfs_log_perror("Failed to truncate AT_BITMAP");
goto err_na;
}
}
}
if (ntfs_attr_pread(na, bpos, 1, &byte) != 1) {
ntfs_log_perror("Failed to read $BITMAP");
goto err_na;
}
if (set)
byte |= bit;
else
byte &= ~bit;
if (ntfs_attr_pwrite(na, bpos, 1, &byte) != 1) {
ntfs_log_perror("Failed to write $Bitmap");
goto err_na;
}
ret = STATUS_OK;
err_na:
ntfs_attr_close(na);
return ret;
}
static int ntfs_ibm_set(ntfs_index_context *icx, VCN vcn)
{
return ntfs_ibm_modify(icx, vcn, 1);
}
static int ntfs_ibm_clear(ntfs_index_context *icx, VCN vcn)
{
return ntfs_ibm_modify(icx, vcn, 0);
}
static VCN ntfs_ibm_get_free(ntfs_index_context *icx)
{
u8 *bm;
int bit;
s64 vcn, byte, size;
ntfs_log_trace("Entering\n");
bm = ntfs_attr_readall(icx->ni, AT_BITMAP, icx->name, icx->name_len,
&size);
if (!bm)
return (VCN)-1;
for (byte = 0; byte < size; byte++) {
if (bm[byte] == 255)
continue;
for (bit = 0; bit < 8; bit++) {
if (!(bm[byte] & (1 << bit))) {
vcn = ntfs_ibm_pos_to_vcn(icx, byte * 8 + bit);
goto out;
}
}
}
vcn = ntfs_ibm_pos_to_vcn(icx, size * 8);
out:
ntfs_log_trace("allocated vcn: %lld\n", (long long)vcn);
if (ntfs_ibm_set(icx, vcn))
vcn = (VCN)-1;
free(bm);
return vcn;
}
static INDEX_BLOCK *ntfs_ir_to_ib(INDEX_ROOT *ir, VCN ib_vcn)
{
INDEX_BLOCK *ib;
INDEX_ENTRY *ie_last;
char *ies_start, *ies_end;
int i;
ntfs_log_trace("Entering\n");
ib = ntfs_ib_alloc(ib_vcn, le32_to_cpu(ir->index_block_size), LEAF_NODE);
if (!ib)
return NULL;
ies_start = (char *)ntfs_ie_get_first(&ir->index);
ies_end = (char *)ntfs_ie_get_end(&ir->index);
ie_last = ntfs_ie_get_last((INDEX_ENTRY *)ies_start, ies_end);
/*
* Copy all entries, including the termination entry
* as well, which can never have any data.
*/
i = (char *)ie_last - ies_start + le16_to_cpu(ie_last->length);
memcpy(ntfs_ie_get_first(&ib->index), ies_start, i);
ib->index.ih_flags = ir->index.ih_flags;
ib->index.index_length = cpu_to_le32(i +
le32_to_cpu(ib->index.entries_offset));
return ib;
}
static void ntfs_ir_nill(INDEX_ROOT *ir)
{
INDEX_ENTRY *ie_last;
char *ies_start, *ies_end;
ntfs_log_trace("Entering\n");
/*
* TODO: This function could be much simpler.
*/
ies_start = (char *)ntfs_ie_get_first(&ir->index);
ies_end = (char *)ntfs_ie_get_end(&ir->index);
ie_last = ntfs_ie_get_last((INDEX_ENTRY *)ies_start, ies_end);
/*
* Move the index root termination entry forward
*/
if ((char *)ie_last > ies_start) {
memmove(ies_start, (char *)ie_last, le16_to_cpu(ie_last->length));
ie_last = (INDEX_ENTRY *)ies_start;
}
}
static int ntfs_ib_copy_tail(ntfs_index_context *icx, INDEX_BLOCK *src,
INDEX_ENTRY *median, VCN new_vcn)
{
u8 *ies_end;
INDEX_ENTRY *ie_head; /* first entry after the median */
int tail_size, ret;
INDEX_BLOCK *dst;
ntfs_log_trace("Entering\n");
dst = ntfs_ib_alloc(new_vcn, icx->block_size,
src->index.ih_flags & NODE_MASK);
if (!dst)
return STATUS_ERROR;
ie_head = ntfs_ie_get_next(median);
ies_end = (u8 *)ntfs_ie_get_end(&src->index);
tail_size = ies_end - (u8 *)ie_head;
memcpy(ntfs_ie_get_first(&dst->index), ie_head, tail_size);
dst->index.index_length = cpu_to_le32(tail_size +
le32_to_cpu(dst->index.entries_offset));
ret = ntfs_ib_write(icx, dst);
free(dst);
return ret;
}
static int ntfs_ib_cut_tail(ntfs_index_context *icx, INDEX_BLOCK *ib,
INDEX_ENTRY *ie)
{
char *ies_start, *ies_end;
INDEX_ENTRY *ie_last;
ntfs_log_trace("Entering\n");
ies_start = (char *)ntfs_ie_get_first(&ib->index);
ies_end = (char *)ntfs_ie_get_end(&ib->index);
ie_last = ntfs_ie_get_last((INDEX_ENTRY *)ies_start, ies_end);
if (ie_last->ie_flags & INDEX_ENTRY_NODE)
ntfs_ie_set_vcn(ie_last, ntfs_ie_get_vcn(ie));
memcpy(ie, ie_last, le16_to_cpu(ie_last->length));
ib->index.index_length = cpu_to_le32(((char *)ie - ies_start) +
le16_to_cpu(ie->length) + le32_to_cpu(ib->index.entries_offset));
if (ntfs_ib_write(icx, ib))
return STATUS_ERROR;
return STATUS_OK;
}
static int ntfs_ia_add(ntfs_index_context *icx)
{
ntfs_log_trace("Entering\n");
if (ntfs_ibm_add(icx))
return -1;
if (!ntfs_attr_exist(icx->ni, AT_INDEX_ALLOCATION, icx->name, icx->name_len)) {
if (ntfs_attr_add(icx->ni, AT_INDEX_ALLOCATION, icx->name,
icx->name_len, NULL, 0)) {
ntfs_log_perror("Failed to add AT_INDEX_ALLOCATION");
return -1;
}
}
icx->ia_na = ntfs_ia_open(icx, icx->ni);
if (!icx->ia_na)
return -1;
return 0;
}
static int ntfs_ir_reparent(ntfs_index_context *icx)
{
ntfs_attr_search_ctx *ctx = NULL;
INDEX_ROOT *ir;
INDEX_ENTRY *ie;
INDEX_BLOCK *ib = NULL;
VCN new_ib_vcn;
int ix_root_size;
int ret = STATUS_ERROR;
ntfs_log_trace("Entering\n");
ir = ntfs_ir_lookup2(icx->ni, icx->name, icx->name_len);
if (!ir)
goto out;
if ((ir->index.ih_flags & NODE_MASK) == SMALL_INDEX)
if (ntfs_ia_add(icx))
goto out;
new_ib_vcn = ntfs_ibm_get_free(icx);
if (new_ib_vcn == -1)
goto out;
ir = ntfs_ir_lookup2(icx->ni, icx->name, icx->name_len);
if (!ir)
goto clear_bmp;
ib = ntfs_ir_to_ib(ir, new_ib_vcn);
if (ib == NULL) {
ntfs_log_perror("Failed to move index root to index block");
goto clear_bmp;
}
if (ntfs_ib_write(icx, ib))
goto clear_bmp;
retry :
ir = ntfs_ir_lookup(icx->ni, icx->name, icx->name_len, &ctx);
if (!ir)
goto clear_bmp;
ntfs_ir_nill(ir);
ie = ntfs_ie_get_first(&ir->index);
ie->ie_flags |= INDEX_ENTRY_NODE;
ie->length = const_cpu_to_le16(sizeof(INDEX_ENTRY_HEADER) + sizeof(VCN));
ir->index.ih_flags = LARGE_INDEX;
ir->index.index_length = cpu_to_le32(le32_to_cpu(ir->index.entries_offset)
+ le16_to_cpu(ie->length));
ir->index.allocated_size = ir->index.index_length;
ix_root_size = sizeof(INDEX_ROOT) - sizeof(INDEX_HEADER)
+ le32_to_cpu(ir->index.allocated_size);
if (ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr,
ix_root_size)) {
/*
* When there is no space to build a non-resident
* index, we may have to move the root to an extent
*/
if ((errno == ENOSPC)
&& (ctx->al_entry || !ntfs_inode_add_attrlist(icx->ni))) {
ntfs_attr_put_search_ctx(ctx);
ctx = (ntfs_attr_search_ctx*)NULL;
ir = ntfs_ir_lookup(icx->ni, icx->name, icx->name_len,
&ctx);
if (ir
&& !ntfs_attr_record_move_away(ctx, ix_root_size
- le32_to_cpu(ctx->attr->value_length))) {
ntfs_attr_put_search_ctx(ctx);
ctx = (ntfs_attr_search_ctx*)NULL;
goto retry;
}
}
/* FIXME: revert index root */
goto clear_bmp;
}
/*
* FIXME: do it earlier if we have enough space in IR (should always),
* so in error case we wouldn't lose the IB.
*/
ntfs_ie_set_vcn(ie, new_ib_vcn);
ret = STATUS_OK;
err_out:
free(ib);
ntfs_attr_put_search_ctx(ctx);
out:
return ret;
clear_bmp:
ntfs_ibm_clear(icx, new_ib_vcn);
goto err_out;
}
/**
* ntfs_ir_truncate - Truncate index root attribute
*
* Returns STATUS_OK, STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT or STATUS_ERROR.
*/
static int ntfs_ir_truncate(ntfs_index_context *icx, int data_size)
{
ntfs_attr *na;
int ret;
ntfs_log_trace("Entering\n");
na = ntfs_attr_open(icx->ni, AT_INDEX_ROOT, icx->name, icx->name_len);
if (!na) {
ntfs_log_perror("Failed to open INDEX_ROOT");
return STATUS_ERROR;
}
/*
* INDEX_ROOT must be resident and its entries can be moved to
* INDEX_BLOCK, so ENOSPC isn't a real error.
*/
ret = ntfs_attr_truncate(na, data_size + offsetof(INDEX_ROOT, index));
if (ret == STATUS_OK) {
icx->ir = ntfs_ir_lookup2(icx->ni, icx->name, icx->name_len);
if (!icx->ir)
return STATUS_ERROR;
icx->ir->index.allocated_size = cpu_to_le32(data_size);
} else if (ret == STATUS_ERROR)
ntfs_log_perror("Failed to truncate INDEX_ROOT");
ntfs_attr_close(na);
return ret;
}
/**
* ntfs_ir_make_space - Make more space for the index root attribute
*
* On success return STATUS_OK or STATUS_KEEP_SEARCHING.
* On error return STATUS_ERROR.
*/
static int ntfs_ir_make_space(ntfs_index_context *icx, int data_size)
{
int ret;
ntfs_log_trace("Entering\n");
ret = ntfs_ir_truncate(icx, data_size);
if (ret == STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT) {
ret = ntfs_ir_reparent(icx);
if (ret == STATUS_OK)
ret = STATUS_KEEP_SEARCHING;
else
ntfs_log_perror("Failed to nodify INDEX_ROOT");
}
return ret;
}
/*
* NOTE: 'ie' must be a copy of a real index entry.
*/
static int ntfs_ie_add_vcn(INDEX_ENTRY **ie)
{
INDEX_ENTRY *p, *old = *ie;
old->length = cpu_to_le16(le16_to_cpu(old->length) + sizeof(VCN));
p = realloc(old, le16_to_cpu(old->length));
if (!p)
return STATUS_ERROR;
p->ie_flags |= INDEX_ENTRY_NODE;
*ie = p;
return STATUS_OK;
}
static int ntfs_ih_insert(INDEX_HEADER *ih, INDEX_ENTRY *orig_ie, VCN new_vcn,
int pos)
{
INDEX_ENTRY *ie_node, *ie;
int ret = STATUS_ERROR;
VCN old_vcn;
ntfs_log_trace("Entering\n");
ie = ntfs_ie_dup(orig_ie);
if (!ie)
return STATUS_ERROR;
if (!(ie->ie_flags & INDEX_ENTRY_NODE))
if (ntfs_ie_add_vcn(&ie))
goto out;
ie_node = ntfs_ie_get_by_pos(ih, pos);
old_vcn = ntfs_ie_get_vcn(ie_node);
ntfs_ie_set_vcn(ie_node, new_vcn);
ntfs_ie_insert(ih, ie, ie_node);
ntfs_ie_set_vcn(ie_node, old_vcn);
ret = STATUS_OK;
out:
free(ie);
return ret;
}
static VCN ntfs_icx_parent_vcn(ntfs_index_context *icx)
{
return icx->parent_vcn[icx->pindex];
}
static VCN ntfs_icx_parent_pos(ntfs_index_context *icx)
{
return icx->parent_pos[icx->pindex];
}
static int ntfs_ir_insert_median(ntfs_index_context *icx, INDEX_ENTRY *median,
VCN new_vcn)
{
u32 new_size;
int ret;
ntfs_log_trace("Entering\n");
icx->ir = ntfs_ir_lookup2(icx->ni, icx->name, icx->name_len);
if (!icx->ir)
return STATUS_ERROR;
new_size = le32_to_cpu(icx->ir->index.index_length) +
le16_to_cpu(median->length);
if (!(median->ie_flags & INDEX_ENTRY_NODE))
new_size += sizeof(VCN);
ret = ntfs_ir_make_space(icx, new_size);
if (ret != STATUS_OK)
return ret;
icx->ir = ntfs_ir_lookup2(icx->ni, icx->name, icx->name_len);
if (!icx->ir)
return STATUS_ERROR;
return ntfs_ih_insert(&icx->ir->index, median, new_vcn,
ntfs_icx_parent_pos(icx));
}
static int ntfs_ib_split(ntfs_index_context *icx, INDEX_BLOCK *ib);
/**
* On success return STATUS_OK or STATUS_KEEP_SEARCHING.
* On error return STATUS_ERROR.
*/
static int ntfs_ib_insert(ntfs_index_context *icx, INDEX_ENTRY *ie, VCN new_vcn)
{
INDEX_BLOCK *ib;
u32 idx_size, allocated_size;
int err = STATUS_ERROR;
VCN old_vcn;
ntfs_log_trace("Entering\n");
ib = ntfs_malloc(icx->block_size);
if (!ib)
return -1;
old_vcn = ntfs_icx_parent_vcn(icx);
if (ntfs_ib_read(icx, old_vcn, ib))
goto err_out;
idx_size = le32_to_cpu(ib->index.index_length);
allocated_size = le32_to_cpu(ib->index.allocated_size);
/* FIXME: sizeof(VCN) should be included only if ie has no VCN */
if (idx_size + le16_to_cpu(ie->length) + sizeof(VCN) > allocated_size) {
err = ntfs_ib_split(icx, ib);
if (err == STATUS_OK)
err = STATUS_KEEP_SEARCHING;
goto err_out;
}
if (ntfs_ih_insert(&ib->index, ie, new_vcn, ntfs_icx_parent_pos(icx)))
goto err_out;
if (ntfs_ib_write(icx, ib))
goto err_out;
err = STATUS_OK;
err_out:
free(ib);
return err;
}
/**
* ntfs_ib_split - Split an index block
*
* On success return STATUS_OK or STATUS_KEEP_SEARCHING.
* On error return is STATUS_ERROR.
*/
static int ntfs_ib_split(ntfs_index_context *icx, INDEX_BLOCK *ib)
{
INDEX_ENTRY *median;
VCN new_vcn;
int ret;
ntfs_log_trace("Entering\n");
if (ntfs_icx_parent_dec(icx))
return STATUS_ERROR;
median = ntfs_ie_get_median(&ib->index);
new_vcn = ntfs_ibm_get_free(icx);
if (new_vcn == -1)
return STATUS_ERROR;
if (ntfs_ib_copy_tail(icx, ib, median, new_vcn)) {
ntfs_ibm_clear(icx, new_vcn);
return STATUS_ERROR;
}
if (ntfs_icx_parent_vcn(icx) == VCN_INDEX_ROOT_PARENT)
ret = ntfs_ir_insert_median(icx, median, new_vcn);
else
ret = ntfs_ib_insert(icx, median, new_vcn);
if (ret != STATUS_OK) {
ntfs_ibm_clear(icx, new_vcn);
return ret;
}
ret = ntfs_ib_cut_tail(icx, ib, median);
return ret;
}
/* JPA static */
int ntfs_ie_add(ntfs_index_context *icx, INDEX_ENTRY *ie)
{
INDEX_HEADER *ih;
int allocated_size, new_size;
int ret = STATUS_ERROR;
#ifdef DEBUG
/* removed by JPA to make function usable for security indexes
char *fn;
fn = ntfs_ie_filename_get(ie);
ntfs_log_trace("file: '%s'\n", fn);
ntfs_attr_name_free(&fn);
*/
#endif
while (1) {
if (!ntfs_index_lookup(&ie->key, le16_to_cpu(ie->key_length), icx)) {
errno = EEXIST;
ntfs_log_perror("Index already have such entry");
goto err_out;
}
if (errno != ENOENT) {
ntfs_log_perror("Failed to find place for new entry");
goto err_out;
}
if (icx->is_in_root)
ih = &icx->ir->index;
else
ih = &icx->ib->index;
allocated_size = le32_to_cpu(ih->allocated_size);
new_size = le32_to_cpu(ih->index_length) + le16_to_cpu(ie->length);
if (new_size <= allocated_size)
break;
ntfs_log_trace("index block sizes: allocated: %d needed: %d\n",
allocated_size, new_size);
if (icx->is_in_root) {
if (ntfs_ir_make_space(icx, new_size) == STATUS_ERROR)
goto err_out;
} else {
if (ntfs_ib_split(icx, icx->ib) == STATUS_ERROR)
goto err_out;
}
ntfs_inode_mark_dirty(icx->actx->ntfs_ino);
ntfs_index_ctx_reinit(icx);
}
ntfs_ie_insert(ih, ie, icx->entry);
ntfs_index_entry_mark_dirty(icx);
ret = STATUS_OK;
err_out:
ntfs_log_trace("%s\n", ret ? "Failed" : "Done");
return ret;
}
/**
* ntfs_index_add_filename - add filename to directory index
* @ni: ntfs inode describing directory to which index add filename
* @fn: FILE_NAME attribute to add
* @mref: reference of the inode which @fn describes
*
* Return 0 on success or -1 on error with errno set to the error code.
*/
int ntfs_index_add_filename(ntfs_inode *ni, FILE_NAME_ATTR *fn, MFT_REF mref)
{
INDEX_ENTRY *ie;
ntfs_index_context *icx;
int fn_size, ie_size, err, ret = -1;
ntfs_log_trace("Entering\n");
if (!ni || !fn) {
ntfs_log_error("Invalid arguments.\n");
errno = EINVAL;
return -1;
}
fn_size = (fn->file_name_length * sizeof(ntfschar)) +
sizeof(FILE_NAME_ATTR);
ie_size = (sizeof(INDEX_ENTRY_HEADER) + fn_size + 7) & ~7;
ie = ntfs_calloc(ie_size);
if (!ie)
return -1;
ie->indexed_file = cpu_to_le64(mref);
ie->length = cpu_to_le16(ie_size);
ie->key_length = cpu_to_le16(fn_size);
memcpy(&ie->key, fn, fn_size);
icx = ntfs_index_ctx_get(ni, NTFS_INDEX_I30, 4);
if (!icx)
goto out;
ret = ntfs_ie_add(icx, ie);
err = errno;
ntfs_index_ctx_put(icx);
errno = err;
out:
free(ie);
return ret;
}
static int ntfs_ih_takeout(ntfs_index_context *icx, INDEX_HEADER *ih,
INDEX_ENTRY *ie, INDEX_BLOCK *ib)
{
INDEX_ENTRY *ie_roam;
int freed_space;
BOOL full;
int ret = STATUS_ERROR;
ntfs_log_trace("Entering\n");
full = ih->index_length == ih->allocated_size;
ie_roam = ntfs_ie_dup_novcn(ie);
if (!ie_roam)
return STATUS_ERROR;
ntfs_ie_delete(ih, ie);
if (ntfs_icx_parent_vcn(icx) == VCN_INDEX_ROOT_PARENT) {
/*
* Recover the space which may have been freed
* while deleting an entry from root index
*/
freed_space = le32_to_cpu(ih->allocated_size)
- le32_to_cpu(ih->index_length);
if (full && (freed_space > 0) && !(freed_space & 7)) {
ntfs_ir_truncate(icx, le32_to_cpu(ih->index_length));
/* do nothing if truncation fails */
}
ntfs_inode_mark_dirty(icx->actx->ntfs_ino);
} else
if (ntfs_ib_write(icx, ib))
goto out;
ntfs_index_ctx_reinit(icx);
ret = ntfs_ie_add(icx, ie_roam);
out:
free(ie_roam);
return ret;
}
/**
* Used if an empty index block to be deleted has END entry as the parent
* in the INDEX_ROOT which is the only one there.
*/
static void ntfs_ir_leafify(ntfs_index_context *icx, INDEX_HEADER *ih)
{
INDEX_ENTRY *ie;
ntfs_log_trace("Entering\n");
ie = ntfs_ie_get_first(ih);
ie->ie_flags &= ~INDEX_ENTRY_NODE;
ie->length = cpu_to_le16(le16_to_cpu(ie->length) - sizeof(VCN));
ih->index_length = cpu_to_le32(le32_to_cpu(ih->index_length) - sizeof(VCN));
ih->ih_flags &= ~LARGE_INDEX;
/* Not fatal error */
ntfs_ir_truncate(icx, le32_to_cpu(ih->index_length));
}
/**
* Used if an empty index block to be deleted has END entry as the parent
* in the INDEX_ROOT which is not the only one there.
*/
static int ntfs_ih_reparent_end(ntfs_index_context *icx, INDEX_HEADER *ih,
INDEX_BLOCK *ib)
{
INDEX_ENTRY *ie, *ie_prev;
ntfs_log_trace("Entering\n");
ie = ntfs_ie_get_by_pos(ih, ntfs_icx_parent_pos(icx));
ie_prev = ntfs_ie_prev(ih, ie);
ntfs_ie_set_vcn(ie, ntfs_ie_get_vcn(ie_prev));
return ntfs_ih_takeout(icx, ih, ie_prev, ib);
}
static int ntfs_index_rm_leaf(ntfs_index_context *icx)
{
INDEX_BLOCK *ib = NULL;
INDEX_HEADER *parent_ih;
INDEX_ENTRY *ie;
int ret = STATUS_ERROR;
ntfs_log_trace("pindex: %d\n", icx->pindex);
if (ntfs_icx_parent_dec(icx))
return STATUS_ERROR;
if (ntfs_ibm_clear(icx, icx->parent_vcn[icx->pindex + 1]))
return STATUS_ERROR;
if (ntfs_icx_parent_vcn(icx) == VCN_INDEX_ROOT_PARENT)
parent_ih = &icx->ir->index;
else {
ib = ntfs_malloc(icx->block_size);
if (!ib)
return STATUS_ERROR;
if (ntfs_ib_read(icx, ntfs_icx_parent_vcn(icx), ib))
goto out;
parent_ih = &ib->index;
}
ie = ntfs_ie_get_by_pos(parent_ih, ntfs_icx_parent_pos(icx));
if (!ntfs_ie_end(ie)) {
ret = ntfs_ih_takeout(icx, parent_ih, ie, ib);
goto out;
}
if (ntfs_ih_zero_entry(parent_ih)) {
if (ntfs_icx_parent_vcn(icx) == VCN_INDEX_ROOT_PARENT) {
ntfs_ir_leafify(icx, parent_ih);
goto ok;
}
ret = ntfs_index_rm_leaf(icx);
goto out;
}
if (ntfs_ih_reparent_end(icx, parent_ih, ib))
goto out;
ok:
ret = STATUS_OK;
out:
free(ib);
return ret;
}
static int ntfs_index_rm_node(ntfs_index_context *icx)
{
int entry_pos, pindex;
VCN vcn;
INDEX_BLOCK *ib = NULL;
INDEX_ENTRY *ie_succ, *ie, *entry = icx->entry;
INDEX_HEADER *ih;
u32 new_size;
int delta, ret = STATUS_ERROR;
ntfs_log_trace("Entering\n");
if (!icx->ia_na) {
icx->ia_na = ntfs_ia_open(icx, icx->ni);
if (!icx->ia_na)
return STATUS_ERROR;
}
ib = ntfs_malloc(icx->block_size);
if (!ib)
return STATUS_ERROR;
ie_succ = ntfs_ie_get_next(icx->entry);
entry_pos = icx->parent_pos[icx->pindex]++;
pindex = icx->pindex;
descend:
vcn = ntfs_ie_get_vcn(ie_succ);
if (ntfs_ib_read(icx, vcn, ib))
goto out;
ie_succ = ntfs_ie_get_first(&ib->index);
if (ntfs_icx_parent_inc(icx))
goto out;
icx->parent_vcn[icx->pindex] = vcn;
icx->parent_pos[icx->pindex] = 0;
if ((ib->index.ih_flags & NODE_MASK) == INDEX_NODE)
goto descend;
if (ntfs_ih_zero_entry(&ib->index)) {
errno = EIO;
ntfs_log_perror("Empty index block");
goto out;
}
ie = ntfs_ie_dup(ie_succ);
if (!ie)
goto out;
if (ntfs_ie_add_vcn(&ie))
goto out2;
ntfs_ie_set_vcn(ie, ntfs_ie_get_vcn(icx->entry));
if (icx->is_in_root)
ih = &icx->ir->index;
else
ih = &icx->ib->index;
delta = le16_to_cpu(ie->length) - le16_to_cpu(icx->entry->length);
new_size = le32_to_cpu(ih->index_length) + delta;
if (delta > 0) {
if (icx->is_in_root) {
ret = ntfs_ir_make_space(icx, new_size);
if (ret != STATUS_OK)
goto out2;
ih = &icx->ir->index;
entry = ntfs_ie_get_by_pos(ih, entry_pos);
} else if (new_size > le32_to_cpu(ih->allocated_size)) {
icx->pindex = pindex;
ret = ntfs_ib_split(icx, icx->ib);
if (ret == STATUS_OK)
ret = STATUS_KEEP_SEARCHING;
goto out2;
}
}
ntfs_ie_delete(ih, entry);
ntfs_ie_insert(ih, ie, entry);
if (icx->is_in_root) {
if (ntfs_ir_truncate(icx, new_size))
goto out2;
} else
if (ntfs_icx_ib_write(icx))
goto out2;
ntfs_ie_delete(&ib->index, ie_succ);
if (ntfs_ih_zero_entry(&ib->index)) {
if (ntfs_index_rm_leaf(icx))
goto out2;
} else
if (ntfs_ib_write(icx, ib))
goto out2;
ret = STATUS_OK;
out2:
free(ie);
out:
free(ib);
return ret;
}
/**
* ntfs_index_rm - remove entry from the index
* @icx: index context describing entry to delete
*
* Delete entry described by @icx from the index. Index context is always
* reinitialized after use of this function, so it can be used for index
* lookup once again.
*
* Return 0 on success or -1 on error with errno set to the error code.
*/
/*static JPA*/
int ntfs_index_rm(ntfs_index_context *icx)
{
INDEX_HEADER *ih;
int err, ret = STATUS_OK;
ntfs_log_trace("Entering\n");
if (!icx || (!icx->ib && !icx->ir) || ntfs_ie_end(icx->entry)) {
ntfs_log_error("Invalid arguments.\n");
errno = EINVAL;
goto err_out;
}
if (icx->is_in_root)
ih = &icx->ir->index;
else
ih = &icx->ib->index;
if (icx->entry->ie_flags & INDEX_ENTRY_NODE) {
ret = ntfs_index_rm_node(icx);
} else if (icx->is_in_root || !ntfs_ih_one_entry(ih)) {
ntfs_ie_delete(ih, icx->entry);
if (icx->is_in_root) {
err = ntfs_ir_truncate(icx, le32_to_cpu(ih->index_length));
if (err != STATUS_OK)
goto err_out;
} else
if (ntfs_icx_ib_write(icx))
goto err_out;
} else {
if (ntfs_index_rm_leaf(icx))
goto err_out;
}
out:
return ret;
err_out:
ret = STATUS_ERROR;
goto out;
}
int ntfs_index_remove(ntfs_inode *dir_ni,
ntfs_inode *ni __attribute__((unused)),
const void *key, const int keylen)
{
int ret = STATUS_ERROR;
ntfs_index_context *icx;
icx = ntfs_index_ctx_get(dir_ni, NTFS_INDEX_I30, 4);
if (!icx)
return -1;
while (1) {
if (ntfs_index_lookup(key, keylen, icx))
goto err_out;
ret = ntfs_index_rm(icx);
if (ret == STATUS_ERROR)
goto err_out;
else if (ret == STATUS_OK)
break;
ntfs_inode_mark_dirty(icx->actx->ntfs_ino);
ntfs_index_ctx_reinit(icx);
}
ntfs_inode_mark_dirty(icx->actx->ntfs_ino);
out:
ntfs_index_ctx_put(icx);
return ret;
err_out:
ret = STATUS_ERROR;
ntfs_log_perror("Delete failed");
goto out;
}
/**
* ntfs_index_root_get - read the index root of an attribute
* @ni: open ntfs inode in which the ntfs attribute resides
* @attr: attribute for which we want its index root
*
* This function will read the related index root an ntfs attribute.
*
* On success a buffer is allocated with the content of the index root
* and which needs to be freed when it's not needed anymore.
*
* On error NULL is returned with errno set to the error code.
*/
INDEX_ROOT *ntfs_index_root_get(ntfs_inode *ni, ATTR_RECORD *attr)
{
ntfs_attr_search_ctx *ctx;
ntfschar *name;
INDEX_ROOT *root = NULL;
name = (ntfschar *)((u8 *)attr + le16_to_cpu(attr->name_offset));
if (!ntfs_ir_lookup(ni, name, attr->name_length, &ctx))
return NULL;
root = ntfs_malloc(sizeof(INDEX_ROOT));
if (!root)
goto out;
*root = *((INDEX_ROOT *)((u8 *)ctx->attr +
le16_to_cpu(ctx->attr->value_offset)));
out:
ntfs_attr_put_search_ctx(ctx);
return root;
}
/*
* Walk down the index tree (leaf bound)
* until there are no subnode in the first index entry
* returns the entry at the bottom left in subnode
*/
static INDEX_ENTRY *ntfs_index_walk_down(INDEX_ENTRY *ie,
ntfs_index_context *ictx)
{
INDEX_ENTRY *entry;
s64 vcn;
entry = ie;
do {
vcn = ntfs_ie_get_vcn(entry);
if (ictx->is_in_root) {
/* down from level zero */
ictx->ir = (INDEX_ROOT*)NULL;
ictx->ib = (INDEX_BLOCK*)ntfs_malloc(ictx->block_size);
ictx->pindex = 1;
ictx->is_in_root = FALSE;
} else {
/* down from non-zero level */
ictx->pindex++;
}
ictx->parent_pos[ictx->pindex] = 0;
ictx->parent_vcn[ictx->pindex] = vcn;
if (!ntfs_ib_read(ictx,vcn,ictx->ib)) {
ictx->entry = ntfs_ie_get_first(&ictx->ib->index);
entry = ictx->entry;
} else
entry = (INDEX_ENTRY*)NULL;
} while (entry && (entry->ie_flags & INDEX_ENTRY_NODE));
return (entry);
}
/*
* Walk up the index tree (root bound)
* until there is a valid data entry in parent
* returns the parent entry or NULL if no more parent
*/
static INDEX_ENTRY *ntfs_index_walk_up(INDEX_ENTRY *ie,
ntfs_index_context *ictx)
{
INDEX_ENTRY *entry;
s64 vcn;
entry = ie;
if (ictx->pindex > 0) {
do {
ictx->pindex--;
if (!ictx->pindex) {
/* we have reached the root */
free(ictx->ib);
ictx->ib = (INDEX_BLOCK*)NULL;
ictx->is_in_root = TRUE;
/* a new search context is to be allocated */
if (ictx->actx)
free(ictx->actx);
ictx->ir = ntfs_ir_lookup(ictx->ni,
ictx->name, ictx->name_len,
&ictx->actx);
if (ictx->ir)
entry = ntfs_ie_get_by_pos(
&ictx->ir->index,
ictx->parent_pos[ictx->pindex]);
else
entry = (INDEX_ENTRY*)NULL;
} else {
/* up into non-root node */
vcn = ictx->parent_vcn[ictx->pindex];
if (!ntfs_ib_read(ictx,vcn,ictx->ib)) {
entry = ntfs_ie_get_by_pos(
&ictx->ib->index,
ictx->parent_pos[ictx->pindex]);
} else
entry = (INDEX_ENTRY*)NULL;
}
ictx->entry = entry;
} while (entry && (ictx->pindex > 0)
&& (entry->ie_flags & INDEX_ENTRY_END));
} else
entry = (INDEX_ENTRY*)NULL;
return (entry);
}
/*
* Get next entry in an index according to collating sequence.
* Must be initialized through a ntfs_index_lookup()
*
* Returns next entry or NULL if none
*
* Sample layout :
*
* +---+---+---+---+---+---+---+---+ n ptrs to subnodes
* | | | 10| 25| 33| | | | n-1 keys in between
* +---+---+---+---+---+---+---+---+ no key in last entry
* | A | A
* | | | +-------------------------------+
* +--------------------------+ | +-----+ |
* | +--+ | |
* V | V |
* +---+---+---+---+---+---+---+---+ | +---+---+---+---+---+---+---+---+
* | 11| 12| 13| 14| 15| 16| 17| | | | 26| 27| 28| 29| 30| 31| 32| |
* +---+---+---+---+---+---+---+---+ | +---+---+---+---+---+---+---+---+
* | |
* +-----------------------+ |
* | |
* +---+---+---+---+---+---+---+---+
* | 18| 19| 20| 21| 22| 23| 24| |
* +---+---+---+---+---+---+---+---+
*/
INDEX_ENTRY *ntfs_index_next(INDEX_ENTRY *ie, ntfs_index_context *ictx)
{
INDEX_ENTRY *next;
le16 flags;
/*
* lookup() may have returned an invalid node
* when searching for a partial key
* if this happens, walk up
*/
if (ie->ie_flags & INDEX_ENTRY_END)
next = ntfs_index_walk_up(ie, ictx);
else {
/*
* get next entry in same node
* there is always one after any entry with data
*/
next = (INDEX_ENTRY*)((char*)ie + le16_to_cpu(ie->length));
++ictx->parent_pos[ictx->pindex];
flags = next->ie_flags;
/* walk down if it has a subnode */
if (flags & INDEX_ENTRY_NODE) {
next = ntfs_index_walk_down(next,ictx);
} else {
/* walk up it has no subnode, nor data */
if (flags & INDEX_ENTRY_END) {
next = ntfs_index_walk_up(next, ictx);
}
}
}
/* return NULL if stuck at end of a block */
if (next && (next->ie_flags & INDEX_ENTRY_END))
next = (INDEX_ENTRY*)NULL;
return (next);
}
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