/**
* 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 VCN *ntfs_ie_get_vcn_addr(INDEX_ENTRY *ie)
{
return (VCN *)((u8 *)ie + le16_to_cpu(ie->length) - sizeof(VCN));
}
/**
* 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;
}
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_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_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 JPA*/
int ntfs_index_rm(ntfs_index_context *icx)
{
INDEX_HEADER *ih = NULL;
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(NULL == ih)
{
errno = EINVAL;
goto err_out;
}
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;
}
/**
* 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;
}
