summaryrefslogtreecommitdiffstats
path: root/lib/ldb/common/ldb_pack.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/ldb/common/ldb_pack.c')
-rw-r--r--lib/ldb/common/ldb_pack.c1360
1 files changed, 1360 insertions, 0 deletions
diff --git a/lib/ldb/common/ldb_pack.c b/lib/ldb/common/ldb_pack.c
new file mode 100644
index 0000000..28b9a8d
--- /dev/null
+++ b/lib/ldb/common/ldb_pack.c
@@ -0,0 +1,1360 @@
+/*
+ ldb database library
+
+ Copyright (C) Andrew Tridgell 2004
+
+ ** NOTE! The following LGPL license applies to the ldb
+ ** library. This does NOT imply that all of Samba is released
+ ** under the LGPL
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3 of the License, or (at your option) any later version.
+
+ This library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ * Name: ldb
+ *
+ * Component: ldb pack/unpack
+ *
+ * Description: pack/unpack routines for ldb messages as key/value blobs
+ *
+ * Author: Andrew Tridgell
+ */
+
+#include "ldb_private.h"
+
+/*
+ * These macros are from byte_array.h via libssh
+ * TODO: This will be replaced with use of the byte_array.h header when it
+ * becomes available.
+ *
+ * Macros for handling integer types in byte arrays
+ *
+ * This file is originally from the libssh.org project
+ *
+ * Copyright (c) 2018 Andreas Schneider <asn@cryptomilk.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#define _DATA_BYTE_CONST(data, pos) \
+ ((uint8_t)(((const uint8_t *)(data))[(pos)]))
+#define PULL_LE_U8(data, pos) \
+ (_DATA_BYTE_CONST(data, pos))
+#define PULL_LE_U16(data, pos) \
+ ((uint16_t)PULL_LE_U8(data, pos) |\
+ ((uint16_t)(PULL_LE_U8(data, (pos) + 1))) << 8)
+#define PULL_LE_U32(data, pos) \
+ ((uint32_t)(PULL_LE_U16(data, pos) |\
+ ((uint32_t)PULL_LE_U16(data, (pos) + 2)) << 16))
+
+#define _DATA_BYTE(data, pos) \
+ (((uint8_t *)(data))[(pos)])
+#define PUSH_LE_U8(data, pos, val) \
+ (_DATA_BYTE(data, pos) = ((uint8_t)(val)))
+#define PUSH_LE_U16(data, pos, val) \
+ (PUSH_LE_U8((data), (pos), (uint8_t)((uint16_t)(val) & 0xff)),\
+ PUSH_LE_U8((data), (pos) + 1,\
+ (uint8_t)((uint16_t)(val) >> 8)))
+#define PUSH_LE_U32(data, pos, val) \
+ (PUSH_LE_U16((data), (pos), (uint16_t)((uint32_t)(val) & 0xffff)),\
+ PUSH_LE_U16((data), (pos) + 2, (uint16_t)((uint32_t)(val) >> 16)))
+
+#define U32_LEN 4
+#define U16_LEN 2
+#define U8_LEN 1
+#define NULL_PAD_BYTE_LEN 1
+
+static int attribute_storable_values(const struct ldb_message_element *el)
+{
+ if (el->num_values == 0) return 0;
+
+ if (ldb_attr_cmp(el->name, "distinguishedName") == 0) return 0;
+
+ return el->num_values;
+}
+
+static int ldb_pack_data_v1(struct ldb_context *ldb,
+ const struct ldb_message *message,
+ struct ldb_val *data)
+{
+ unsigned int i, j, real_elements=0;
+ size_t size, dn_len, attr_len, value_len;
+ const char *dn;
+ uint8_t *p;
+ size_t len;
+
+ dn = ldb_dn_get_linearized(message->dn);
+ if (dn == NULL) {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ /* work out how big it needs to be */
+ size = U32_LEN * 2 + NULL_PAD_BYTE_LEN;
+
+ dn_len = strlen(dn);
+ if (size + dn_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += dn_len;
+
+ /*
+ * First calcuate the buffer size we need, and check for
+ * overflows
+ */
+ for (i=0;i<message->num_elements;i++) {
+ if (attribute_storable_values(&message->elements[i]) == 0) {
+ continue;
+ }
+
+ real_elements++;
+
+ if (size + U32_LEN + NULL_PAD_BYTE_LEN < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += U32_LEN + NULL_PAD_BYTE_LEN;
+
+ attr_len = strlen(message->elements[i].name);
+ if (size + attr_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += attr_len;
+
+ for (j=0;j<message->elements[i].num_values;j++) {
+ if (size + U32_LEN + NULL_PAD_BYTE_LEN < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += U32_LEN + NULL_PAD_BYTE_LEN;
+
+ value_len = message->elements[i].values[j].length;
+ if (size + value_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += value_len;
+ }
+ }
+
+ /* allocate it */
+ data->data = talloc_array(ldb, uint8_t, size);
+ if (!data->data) {
+ errno = ENOMEM;
+ return -1;
+ }
+ data->length = size;
+
+ p = data->data;
+ PUSH_LE_U32(p, 0, LDB_PACKING_FORMAT);
+ p += U32_LEN;
+ PUSH_LE_U32(p, 0, real_elements);
+ p += U32_LEN;
+
+ /* the dn needs to be packed so we can be case preserving
+ while hashing on a case folded dn */
+ len = dn_len;
+ memcpy(p, dn, len+NULL_PAD_BYTE_LEN);
+ p += len + NULL_PAD_BYTE_LEN;
+
+ for (i=0;i<message->num_elements;i++) {
+ if (attribute_storable_values(&message->elements[i]) == 0) {
+ continue;
+ }
+ len = strlen(message->elements[i].name);
+ memcpy(p, message->elements[i].name, len+NULL_PAD_BYTE_LEN);
+ p += len + NULL_PAD_BYTE_LEN;
+ PUSH_LE_U32(p, 0, message->elements[i].num_values);
+ p += U32_LEN;
+ for (j=0;j<message->elements[i].num_values;j++) {
+ PUSH_LE_U32(p, 0,
+ message->elements[i].values[j].length);
+ p += U32_LEN;
+ memcpy(p, message->elements[i].values[j].data,
+ message->elements[i].values[j].length);
+ p[message->elements[i].values[j].length] = 0;
+ p += message->elements[i].values[j].length +
+ NULL_PAD_BYTE_LEN;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * New pack version designed based on performance profiling of version 1.
+ * The approach is to separate value data from the rest of the record's data.
+ * This improves performance because value data is not needed during unpacking
+ * or filtering of the message's attribute list. During filtering we only copy
+ * attributes which are present in the attribute list, however at the parse
+ * stage we need to point to all attributes as they may be referenced in the
+ * search expression.
+ * With this new format, we don't lose time loading data (eg via
+ * talloc_memdup()) that is never needed (for the vast majority of attributes
+ * are are never found in either the search expression or attribute list).
+ * Additional changes include adding a canonicalized DN (for later
+ * optimizations) and variable width length fields for faster unpacking.
+ * The pack and unpack performance improvement is tested in the torture
+ * test torture_ldb_pack_format_perf.
+ *
+ * Layout:
+ *
+ * Version (4 bytes)
+ * Number of Elements (4 bytes)
+ * DN length (4 bytes)
+ * DN with null terminator (DN length + 1 bytes)
+ * Canonicalized DN length (4 bytes)
+ * Canonicalized DN with null terminator (Canonicalized DN length + 1 bytes)
+ * Number of bytes from here to value data section (4 bytes)
+ * # For each element:
+ * Element name length (4 bytes)
+ * Element name with null terminator (Element name length + 1 bytes)
+ * Number of values (4 bytes)
+ * Width of value lengths
+ * # For each value:
+ * Value data length (#bytes given by width field above)
+ * # For each element:
+ * # For each value:
+ * Value data (#bytes given by corresponding length above)
+ */
+static int ldb_pack_data_v2(struct ldb_context *ldb,
+ const struct ldb_message *message,
+ struct ldb_val *data)
+{
+ unsigned int i, j, real_elements=0;
+ size_t size, dn_len, dn_canon_len, attr_len, value_len;
+ const char *dn, *dn_canon;
+ uint8_t *p, *q;
+ size_t len;
+ size_t max_val_len;
+ uint8_t val_len_width;
+
+ /*
+ * First half of this function will calculate required size for
+ * packed data. Initial size is 20 = 5 * 4. 5 fixed fields are:
+ * version, num elements, dn len, canon dn len, attr section len
+ */
+ size = U32_LEN * 5;
+
+ /*
+ * Get linearized and canonicalized form of the DN and add the lengths
+ * of each to size, plus 1 for null terminator.
+ */
+ dn = ldb_dn_get_linearized(message->dn);
+ if (dn == NULL) {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ dn_len = strlen(dn) + NULL_PAD_BYTE_LEN;
+ if (size + dn_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += dn_len;
+
+ if (ldb_dn_is_special(message->dn)) {
+ dn_canon_len = NULL_PAD_BYTE_LEN;
+ dn_canon = discard_const_p(char, "\0");
+ } else {
+ dn_canon = ldb_dn_canonical_string(message->dn, message->dn);
+ if (dn_canon == NULL) {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ dn_canon_len = strlen(dn_canon) + NULL_PAD_BYTE_LEN;
+ if (size + dn_canon_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ }
+ size += dn_canon_len;
+
+ /* Add the size required by each element */
+ for (i=0;i<message->num_elements;i++) {
+ if (attribute_storable_values(&message->elements[i]) == 0) {
+ continue;
+ }
+
+ real_elements++;
+
+ /*
+ * Add length of element name + 9 for:
+ * 1 for null terminator
+ * 4 for element name length field
+ * 4 for number of values field
+ */
+ attr_len = strlen(message->elements[i].name);
+ if (size + attr_len + U32_LEN * 2 + NULL_PAD_BYTE_LEN < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += attr_len + U32_LEN * 2 + NULL_PAD_BYTE_LEN;
+
+ /*
+ * Find the max value length, so we can calculate the width
+ * required for the value length fields.
+ */
+ max_val_len = 0;
+ for (j=0;j<message->elements[i].num_values;j++) {
+ value_len = message->elements[i].values[j].length;
+ if (value_len > max_val_len) {
+ max_val_len = value_len;
+ }
+
+ if (size + value_len + NULL_PAD_BYTE_LEN < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += value_len + NULL_PAD_BYTE_LEN;
+ }
+
+ if (max_val_len <= UCHAR_MAX) {
+ val_len_width = U8_LEN;
+ } else if (max_val_len <= USHRT_MAX) {
+ val_len_width = U16_LEN;
+ } else if (max_val_len <= UINT_MAX) {
+ val_len_width = U32_LEN;
+ } else {
+ errno = EMSGSIZE;
+ return -1;
+ }
+
+ /* Total size required for val lengths (re-using variable) */
+ max_val_len = (val_len_width*message->elements[i].num_values);
+
+ /* Add one for storing the width */
+ max_val_len += U8_LEN;
+ if (size + max_val_len < size) {
+ errno = ENOMEM;
+ return -1;
+ }
+ size += max_val_len;
+ }
+
+ /* Allocate */
+ data->data = talloc_array(ldb, uint8_t, size);
+ if (!data->data) {
+ errno = ENOMEM;
+ return -1;
+ }
+ data->length = size;
+
+ /* Packing format version and number of element */
+ p = data->data;
+ PUSH_LE_U32(p, 0, LDB_PACKING_FORMAT_V2);
+ p += U32_LEN;
+ PUSH_LE_U32(p, 0, real_elements);
+ p += U32_LEN;
+
+ /* Pack DN and Canonicalized DN */
+ PUSH_LE_U32(p, 0, dn_len-NULL_PAD_BYTE_LEN);
+ p += U32_LEN;
+ memcpy(p, dn, dn_len);
+ p += dn_len;
+
+ PUSH_LE_U32(p, 0, dn_canon_len-NULL_PAD_BYTE_LEN);
+ p += U32_LEN;
+ memcpy(p, dn_canon, dn_canon_len);
+ p += dn_canon_len;
+
+ /*
+ * Save pointer at this point and leave a U32_LEN gap for
+ * storing the size of the attribute names and value lengths
+ * section
+ */
+ q = p;
+ p += U32_LEN;
+
+ for (i=0;i<message->num_elements;i++) {
+ if (attribute_storable_values(&message->elements[i]) == 0) {
+ continue;
+ }
+
+ /* Length of el name */
+ len = strlen(message->elements[i].name);
+ PUSH_LE_U32(p, 0, len);
+ p += U32_LEN;
+
+ /*
+ * Even though we have the element name's length, put a null
+ * terminator at the end so if any code uses the name
+ * directly, it'll be safe to do things requiring null
+ * termination like strlen
+ */
+ memcpy(p, message->elements[i].name, len+NULL_PAD_BYTE_LEN);
+ p += len + NULL_PAD_BYTE_LEN;
+ /* Num values */
+ PUSH_LE_U32(p, 0, message->elements[i].num_values);
+ p += U32_LEN;
+
+ /*
+ * Calculate value length width again. It's faster to
+ * calculate it again than do the array management to
+ * store the result during size calculation.
+ */
+ max_val_len = 0;
+ for (j=0;j<message->elements[i].num_values;j++) {
+ value_len = message->elements[i].values[j].length;
+ if (value_len > max_val_len) {
+ max_val_len = value_len;
+ }
+ }
+
+ if (max_val_len <= UCHAR_MAX) {
+ val_len_width = U8_LEN;
+ } else if (max_val_len <= USHRT_MAX) {
+ val_len_width = U16_LEN;
+ } else if (max_val_len <= UINT_MAX) {
+ val_len_width = U32_LEN;
+ } else {
+ errno = EMSGSIZE;
+ return -1;
+ }
+
+ /* Pack the width */
+ *p = val_len_width & 0xFF;
+ p += U8_LEN;
+
+ /*
+ * Pack each value's length using the minimum number of bytes
+ * required, which we just calculated. We repeat the loop
+ * for each case here so the compiler can inline code.
+ */
+ if (val_len_width == U8_LEN) {
+ for (j=0;j<message->elements[i].num_values;j++) {
+ PUSH_LE_U8(p, 0,
+ message->elements[i].values[j].length);
+ p += U8_LEN;
+ }
+ } else if (val_len_width == U16_LEN) {
+ for (j=0;j<message->elements[i].num_values;j++) {
+ PUSH_LE_U16(p, 0,
+ message->elements[i].values[j].length);
+ p += U16_LEN;
+ }
+ } else if (val_len_width == U32_LEN) {
+ for (j=0;j<message->elements[i].num_values;j++) {
+ PUSH_LE_U32(p, 0,
+ message->elements[i].values[j].length);
+ p += U32_LEN;
+ }
+ }
+ }
+
+ /*
+ * We've finished packing the attr names and value lengths
+ * section, so store the size in the U32_LEN gap we left
+ * earlier
+ */
+ PUSH_LE_U32(q, 0, p-q);
+
+ /* Now pack the values */
+ for (i=0;i<message->num_elements;i++) {
+ if (attribute_storable_values(&message->elements[i]) == 0) {
+ continue;
+ }
+ for (j=0;j<message->elements[i].num_values;j++) {
+ memcpy(p, message->elements[i].values[j].data,
+ message->elements[i].values[j].length);
+
+ /*
+ * Even though we have the data length, put a null
+ * terminator at the end of each value's data so if
+ * any code uses the data directly, it'll be safe to
+ * do things requiring null termination like strlen.
+ */
+ p[message->elements[i].values[j].length] = 0;
+ p += message->elements[i].values[j].length +
+ NULL_PAD_BYTE_LEN;
+ }
+ }
+
+ /*
+ * If we didn't end up at the end of the data here, something has
+ * gone very wrong.
+ */
+ if (p != data->data + size) {
+ errno = ENOMEM;
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ pack a ldb message into a linear buffer in a ldb_val
+
+ note that this routine avoids saving elements with zero values,
+ as these are equivalent to having no element
+
+ caller frees the data buffer after use
+*/
+int ldb_pack_data(struct ldb_context *ldb,
+ const struct ldb_message *message,
+ struct ldb_val *data,
+ uint32_t pack_format_version) {
+
+ if (pack_format_version == LDB_PACKING_FORMAT) {
+ return ldb_pack_data_v1(ldb, message, data);
+ } else if (pack_format_version == LDB_PACKING_FORMAT_V2) {
+ return ldb_pack_data_v2(ldb, message, data);
+ } else {
+ errno = EINVAL;
+ return -1;
+ }
+}
+
+/*
+ * Unpack a ldb message from a linear buffer in ldb_val
+ */
+static int ldb_unpack_data_flags_v1(struct ldb_context *ldb,
+ const struct ldb_val *data,
+ struct ldb_message *message,
+ unsigned int flags,
+ unsigned format)
+{
+ uint8_t *p;
+ size_t remaining;
+ size_t dn_len;
+ unsigned int i, j;
+ unsigned int nelem = 0;
+ size_t len;
+ struct ldb_val *ldb_val_single_array = NULL;
+
+ message->elements = NULL;
+
+ p = data->data;
+
+ /* Format (U32, already read) + U32 for num_elements */
+ if (data->length < U32_LEN * 2) {
+ errno = EIO;
+ goto failed;
+ }
+
+ /* Skip first 4 bytes, format already read */
+ p += U32_LEN;
+ message->num_elements = PULL_LE_U32(p, 0);
+ p += U32_LEN;
+
+ remaining = data->length - U32_LEN * 2;
+
+ switch (format) {
+ case LDB_PACKING_FORMAT_NODN:
+ message->dn = NULL;
+ break;
+
+ case LDB_PACKING_FORMAT:
+ /*
+ * With this check, we know that the DN at p is \0
+ * terminated.
+ */
+ dn_len = strnlen((char *)p, remaining);
+ if (dn_len == remaining) {
+ errno = EIO;
+ goto failed;
+ }
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_DN) {
+ message->dn = NULL;
+ } else {
+ struct ldb_val blob;
+ blob.data = discard_const_p(uint8_t, p);
+ blob.length = dn_len;
+ message->dn = ldb_dn_from_ldb_val(message, ldb, &blob);
+ if (message->dn == NULL) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+ /*
+ * Redundant: by definition, remaining must be more
+ * than one less than dn_len, as otherwise it would be
+ * == dn_len
+ */
+ if (remaining < dn_len + NULL_PAD_BYTE_LEN) {
+ errno = EIO;
+ goto failed;
+ }
+ remaining -= dn_len + NULL_PAD_BYTE_LEN;
+ p += dn_len + NULL_PAD_BYTE_LEN;
+ break;
+
+ default:
+ errno = EIO;
+ goto failed;
+ }
+
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_ATTRS) {
+ return 0;
+ }
+
+ if (message->num_elements == 0) {
+ return 0;
+ }
+
+ if (message->num_elements > remaining / 6) {
+ errno = EIO;
+ goto failed;
+ }
+
+ message->elements = talloc_zero_array(message, struct ldb_message_element,
+ message->num_elements);
+ if (!message->elements) {
+ errno = ENOMEM;
+ goto failed;
+ }
+
+ /*
+ * In typical use, most values are single-valued. This makes
+ * it quite expensive to allocate an array of ldb_val for each
+ * of these, just to then hold the pointer to the data buffer
+ * So with LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC we allocate this
+ * ahead of time and use it for the single values where possible.
+ * (This is used the the normal search case, but not in the
+ * index case because of caller requirements).
+ */
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC) {
+ ldb_val_single_array = talloc_array(message->elements, struct ldb_val,
+ message->num_elements);
+ if (ldb_val_single_array == NULL) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+
+ for (i=0;i<message->num_elements;i++) {
+ const char *attr = NULL;
+ size_t attr_len;
+ struct ldb_message_element *element = NULL;
+
+ /*
+ * Sanity check: Element must be at least the size of empty
+ * attr name and value and NULL terms for each.
+ */
+ if (remaining < U32_LEN * 2 + NULL_PAD_BYTE_LEN * 2) {
+ errno = EIO;
+ goto failed;
+ }
+
+ /*
+ * With this check, we know that the attribute name at
+ * p is \0 terminated.
+ */
+ attr_len = strnlen((char *)p, remaining-6);
+ if (attr_len == remaining-6) {
+ errno = EIO;
+ goto failed;
+ }
+ if (attr_len == 0) {
+ errno = EIO;
+ goto failed;
+ }
+ attr = (char *)p;
+
+ element = &message->elements[nelem];
+ element->name = attr;
+ element->flags = 0;
+
+ if (remaining < (attr_len + NULL_PAD_BYTE_LEN)) {
+ errno = EIO;
+ goto failed;
+ }
+ remaining -= attr_len + NULL_PAD_BYTE_LEN;
+ p += attr_len + NULL_PAD_BYTE_LEN;
+ element->num_values = PULL_LE_U32(p, 0);
+ element->values = NULL;
+ if ((flags & LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC) && element->num_values == 1) {
+ element->values = &ldb_val_single_array[nelem];
+ element->flags |= LDB_FLAG_INTERNAL_SHARED_VALUES;
+ } else if (element->num_values != 0) {
+ element->values = talloc_array(message->elements,
+ struct ldb_val,
+ element->num_values);
+ if (!element->values) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+ p += U32_LEN;
+ if (remaining < U32_LEN) {
+ errno = EIO;
+ goto failed;
+ }
+ remaining -= U32_LEN;
+ for (j = 0; j < element->num_values; j++) {
+ /*
+ * Sanity check: Value must be at least the size of
+ * empty val and NULL terminator.
+ */
+ if (remaining < U32_LEN + NULL_PAD_BYTE_LEN) {
+ errno = EIO;
+ goto failed;
+ }
+ remaining -= U32_LEN + NULL_PAD_BYTE_LEN;
+
+ len = PULL_LE_U32(p, 0);
+ if (remaining < len) {
+ errno = EIO;
+ goto failed;
+ }
+ if (len + NULL_PAD_BYTE_LEN < len) {
+ errno = EIO;
+ goto failed;
+ }
+
+ element->values[j].length = len;
+ element->values[j].data = p + U32_LEN;
+ remaining -= len;
+ p += len + U32_LEN + NULL_PAD_BYTE_LEN;
+ }
+ nelem++;
+ }
+ /*
+ * Adapt the number of elements to the real number of unpacked elements,
+ * it means that we overallocated elements array.
+ */
+ message->num_elements = nelem;
+
+ /*
+ * Shrink the allocated size. On current talloc behaviour
+ * this will help if we skipped 32 or more attributes.
+ */
+ message->elements = talloc_realloc(message, message->elements,
+ struct ldb_message_element,
+ message->num_elements);
+
+ if (remaining != 0) {
+ ldb_debug(ldb, LDB_DEBUG_ERROR,
+ "Error: %zu bytes unread in ldb_unpack_data_flags",
+ remaining);
+ }
+
+ return 0;
+
+failed:
+ talloc_free(message->elements);
+ return -1;
+}
+
+/*
+ * Unpack a ldb message from a linear buffer in ldb_val
+ */
+static int ldb_unpack_data_flags_v2(struct ldb_context *ldb,
+ const struct ldb_val *data,
+ struct ldb_message *message,
+ unsigned int flags)
+{
+ uint8_t *p, *q, *end_p, *value_section_p;
+ unsigned int i, j;
+ unsigned int nelem = 0;
+ size_t len;
+ struct ldb_val *ldb_val_single_array = NULL;
+ uint8_t val_len_width;
+
+ message->elements = NULL;
+
+ p = data->data;
+ end_p = p + data->length;
+
+ /* Skip first 4 bytes, format already read */
+ p += U32_LEN;
+
+ /* First fields are fixed: num_elements, DN length */
+ if (p + U32_LEN * 2 > end_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ message->num_elements = PULL_LE_U32(p, 0);
+ p += U32_LEN;
+
+ len = PULL_LE_U32(p, 0);
+ p += U32_LEN;
+
+ if (p + len + NULL_PAD_BYTE_LEN > end_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_DN) {
+ message->dn = NULL;
+ } else {
+ struct ldb_val blob;
+ blob.data = discard_const_p(uint8_t, p);
+ blob.length = len;
+ message->dn = ldb_dn_from_ldb_val(message, ldb, &blob);
+ if (message->dn == NULL) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+
+ p += len + NULL_PAD_BYTE_LEN;
+
+ if (*(p-NULL_PAD_BYTE_LEN) != '\0') {
+ errno = EINVAL;
+ goto failed;
+ }
+
+ /* Now skip the canonicalized DN and its length */
+ len = PULL_LE_U32(p, 0) + NULL_PAD_BYTE_LEN;
+ p += U32_LEN;
+
+ if (p + len > end_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ p += len;
+
+ if (*(p-NULL_PAD_BYTE_LEN) != '\0') {
+ errno = EINVAL;
+ goto failed;
+ }
+
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_ATTRS) {
+ return 0;
+ }
+
+ if (message->num_elements == 0) {
+ return 0;
+ }
+
+ /*
+ * Sanity check (17 bytes is the minimum element size)
+ */
+ if (message->num_elements > (end_p - p) / 17) {
+ errno = EIO;
+ goto failed;
+ }
+
+ message->elements = talloc_zero_array(message,
+ struct ldb_message_element,
+ message->num_elements);
+ if (!message->elements) {
+ errno = ENOMEM;
+ goto failed;
+ }
+
+ /*
+ * In typical use, most values are single-valued. This makes
+ * it quite expensive to allocate an array of ldb_val for each
+ * of these, just to then hold the pointer to the data buffer.
+ * So with LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC we allocate this
+ * ahead of time and use it for the single values where possible.
+ * (This is used the the normal search case, but not in the
+ * index case because of caller requirements).
+ */
+ if (flags & LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC) {
+ ldb_val_single_array = talloc_array(message->elements,
+ struct ldb_val,
+ message->num_elements);
+ if (ldb_val_single_array == NULL) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+
+ q = p + PULL_LE_U32(p, 0);
+ value_section_p = q;
+ p += U32_LEN;
+
+ for (i=0;i<message->num_elements;i++) {
+ const char *attr = NULL;
+ size_t attr_len;
+ struct ldb_message_element *element = NULL;
+
+ /* Sanity check: minimum element size */
+ if (p + (U32_LEN * 2) + /* attr name len, num values */
+ (U8_LEN * 2) + /* value length width, one val length */
+ (NULL_PAD_BYTE_LEN * 2) /* null for attr name + val */
+ > value_section_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ attr_len = PULL_LE_U32(p, 0);
+ p += U32_LEN;
+
+ if (attr_len == 0) {
+ errno = EIO;
+ goto failed;
+ }
+ attr = (char *)p;
+
+ p += attr_len + NULL_PAD_BYTE_LEN;
+ /*
+ * num_values, val_len_width
+ *
+ * val_len_width is the width specifier
+ * for the variable length encoding
+ */
+ if (p + U32_LEN + U8_LEN > value_section_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ if (*(p-NULL_PAD_BYTE_LEN) != '\0') {
+ errno = EINVAL;
+ goto failed;
+ }
+
+ element = &message->elements[nelem];
+ element->name = attr;
+ element->flags = 0;
+
+ element->num_values = PULL_LE_U32(p, 0);
+ element->values = NULL;
+ if ((flags & LDB_UNPACK_DATA_FLAG_NO_VALUES_ALLOC) &&
+ element->num_values == 1) {
+ element->values = &ldb_val_single_array[nelem];
+ element->flags |= LDB_FLAG_INTERNAL_SHARED_VALUES;
+ } else if (element->num_values != 0) {
+ element->values = talloc_array(message->elements,
+ struct ldb_val,
+ element->num_values);
+ if (!element->values) {
+ errno = ENOMEM;
+ goto failed;
+ }
+ }
+
+ p += U32_LEN;
+
+ /*
+ * Here we read how wide the remaining lengths are
+ * which avoids storing and parsing a lot of leading
+ * 0s
+ */
+ val_len_width = *p;
+ p += U8_LEN;
+
+ if (p + val_len_width * element->num_values >
+ value_section_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ /*
+ * This is structured weird for compiler optimization
+ * purposes, but we need to pull the array of widths
+ * with different macros depending on how wide the
+ * biggest one is (specified by val_len_width)
+ */
+ if (val_len_width == U8_LEN) {
+ for (j = 0; j < element->num_values; j++) {
+ element->values[j].length = PULL_LE_U8(p, 0);
+ p += U8_LEN;
+ }
+ } else if (val_len_width == U16_LEN) {
+ for (j = 0; j < element->num_values; j++) {
+ element->values[j].length = PULL_LE_U16(p, 0);
+ p += U16_LEN;
+ }
+ } else if (val_len_width == U32_LEN) {
+ for (j = 0; j < element->num_values; j++) {
+ element->values[j].length = PULL_LE_U32(p, 0);
+ p += U32_LEN;
+ }
+ } else {
+ errno = ERANGE;
+ goto failed;
+ }
+
+ for (j = 0; j < element->num_values; j++) {
+ len = element->values[j].length;
+ if (len + NULL_PAD_BYTE_LEN < len) {
+ errno = EIO;
+ goto failed;
+ }
+ if (q + len + NULL_PAD_BYTE_LEN > end_p) {
+ errno = EIO;
+ goto failed;
+ }
+
+ element->values[j].data = q;
+ q += len + NULL_PAD_BYTE_LEN;
+ }
+ nelem++;
+ }
+
+ /*
+ * If p isn't now pointing at the beginning of the value section,
+ * something went very wrong.
+ */
+ if (p != value_section_p) {
+ ldb_debug(ldb, LDB_DEBUG_ERROR,
+ "Error: Data corruption in ldb_unpack_data_flags");
+ errno = EIO;
+ goto failed;
+ }
+
+ /*
+ * Adapt the number of elements to the real number of unpacked
+ * elements it means that we overallocated elements array.
+ */
+ message->num_elements = nelem;
+
+ /*
+ * Shrink the allocated size. On current talloc behaviour
+ * this will help if we skipped 32 or more attributes.
+ */
+ message->elements = talloc_realloc(message, message->elements,
+ struct ldb_message_element,
+ message->num_elements);
+
+ if (q != end_p) {
+ ldb_debug(ldb, LDB_DEBUG_ERROR,
+ "Error: %zu bytes unread in ldb_unpack_data_flags",
+ end_p - q);
+ errno = EIO;
+ goto failed;
+ }
+
+ return 0;
+
+failed:
+ talloc_free(message->elements);
+ return -1;
+}
+
+int ldb_unpack_get_format(const struct ldb_val *data,
+ uint32_t *pack_format_version)
+{
+ if (data->length < U32_LEN) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+ *pack_format_version = PULL_LE_U32(data->data, 0);
+ return LDB_SUCCESS;
+}
+
+/*
+ * Unpack a ldb message from a linear buffer in ldb_val
+ */
+int ldb_unpack_data_flags(struct ldb_context *ldb,
+ const struct ldb_val *data,
+ struct ldb_message *message,
+ unsigned int flags)
+{
+ unsigned format;
+
+ if (data->length < U32_LEN) {
+ errno = EIO;
+ return -1;
+ }
+
+ format = PULL_LE_U32(data->data, 0);
+ if (format == LDB_PACKING_FORMAT_V2) {
+ return ldb_unpack_data_flags_v2(ldb, data, message, flags);
+ }
+
+ /*
+ * The v1 function we're about to call takes either LDB_PACKING_FORMAT
+ * or LDB_PACKING_FORMAT_NODN packing format versions, and will error
+ * if given some other version, so we don't need to do any further
+ * checks on 'format'.
+ */
+ return ldb_unpack_data_flags_v1(ldb, data, message, flags, format);
+}
+
+
+/*
+ * Unpack a ldb message from a linear buffer in ldb_val
+ *
+ * Free with ldb_unpack_data_free()
+ */
+int ldb_unpack_data(struct ldb_context *ldb,
+ const struct ldb_val *data,
+ struct ldb_message *message)
+{
+ return ldb_unpack_data_flags(ldb, data, message, 0);
+}
+
+/*
+ add the special distinguishedName element
+*/
+int ldb_msg_add_distinguished_name(struct ldb_message *msg)
+{
+ const char *dn_attr = "distinguishedName";
+ char *dn = NULL;
+
+ if (ldb_msg_find_element(msg, dn_attr)) {
+ /*
+ * This should not happen, but this is
+ * existing behaviour...
+ */
+ return LDB_SUCCESS;
+ }
+
+ dn = ldb_dn_alloc_linearized(msg, msg->dn);
+ if (dn == NULL) {
+ return LDB_ERR_OPERATIONS_ERROR;
+ }
+
+ return ldb_msg_add_steal_string(msg, dn_attr, dn);
+}
+
+/*
+ * filter the specified list of attributes from msg,
+ * adding requested attributes, and perhaps all for *,
+ * but not the DN to filtered_msg.
+ */
+int ldb_filter_attrs(struct ldb_context *ldb,
+ const struct ldb_message *msg,
+ const char *const *attrs,
+ struct ldb_message *filtered_msg)
+{
+ unsigned int i;
+ bool keep_all = false;
+ bool add_dn = false;
+ uint32_t num_elements;
+ uint32_t elements_size;
+
+ if (attrs) {
+ /* check for special attrs */
+ for (i = 0; attrs[i]; i++) {
+ int cmp = strcmp(attrs[i], "*");
+ if (cmp == 0) {
+ keep_all = true;
+ break;
+ }
+ cmp = ldb_attr_cmp(attrs[i], "distinguishedName");
+ if (cmp == 0) {
+ add_dn = true;
+ }
+ }
+ } else {
+ keep_all = true;
+ }
+
+ if (keep_all) {
+ add_dn = true;
+ elements_size = msg->num_elements + 1;
+
+ /* Shortcuts for the simple cases */
+ } else if (add_dn && i == 1) {
+ if (ldb_msg_add_distinguished_name(filtered_msg) != 0) {
+ goto failed;
+ }
+ return 0;
+ } else if (i == 0) {
+ return 0;
+
+ /*
+ * Otherwise we are copying at most as many elements as we
+ * have attributes
+ */
+ } else {
+ elements_size = i;
+ }
+
+ filtered_msg->elements = talloc_array(filtered_msg,
+ struct ldb_message_element,
+ elements_size);
+ if (filtered_msg->elements == NULL) goto failed;
+
+ num_elements = 0;
+
+ for (i = 0; i < msg->num_elements; i++) {
+ struct ldb_message_element *el = &msg->elements[i];
+
+ /*
+ * el2 is assigned after the Pigeonhole principle
+ * check below for clarity
+ */
+ struct ldb_message_element *el2 = NULL;
+ unsigned int j;
+
+ if (keep_all == false) {
+ bool found = false;
+ for (j = 0; attrs[j]; j++) {
+ int cmp = ldb_attr_cmp(el->name, attrs[j]);
+ if (cmp == 0) {
+ found = true;
+ break;
+ }
+ }
+ if (found == false) {
+ continue;
+ }
+ }
+
+ /*
+ * Pigeonhole principle: we can't have more elements
+ * than the number of attributes if they are unique in
+ * the DB.
+ */
+ if (num_elements >= elements_size) {
+ goto failed;
+ }
+
+ el2 = &filtered_msg->elements[num_elements];
+
+ *el2 = *el;
+ el2->name = talloc_strdup(filtered_msg->elements,
+ el->name);
+ if (el2->name == NULL) {
+ goto failed;
+ }
+ el2->values = talloc_array(filtered_msg->elements,
+ struct ldb_val, el->num_values);
+ if (el2->values == NULL) {
+ goto failed;
+ }
+ for (j=0;j<el->num_values;j++) {
+ el2->values[j] = ldb_val_dup(el2->values, &el->values[j]);
+ if (el2->values[j].data == NULL && el->values[j].length != 0) {
+ goto failed;
+ }
+ }
+ num_elements++;
+ }
+
+ filtered_msg->num_elements = num_elements;
+
+ if (add_dn) {
+ if (ldb_msg_add_distinguished_name(filtered_msg) != 0) {
+ goto failed;
+ }
+ }
+
+ if (filtered_msg->num_elements > 0) {
+ filtered_msg->elements
+ = talloc_realloc(filtered_msg,
+ filtered_msg->elements,
+ struct ldb_message_element,
+ filtered_msg->num_elements);
+ if (filtered_msg->elements == NULL) {
+ goto failed;
+ }
+ } else {
+ TALLOC_FREE(filtered_msg->elements);
+ }
+
+ return 0;
+failed:
+ TALLOC_FREE(filtered_msg->elements);
+ return -1;
+}
+
+/*
+ * filter the specified list of attributes from msg,
+ * adding requested attributes, and perhaps all for *.
+ * Unlike ldb_filter_attrs(), the DN will not be added
+ * if it is missing.
+ */
+int ldb_filter_attrs_in_place(struct ldb_message *msg,
+ const char *const *attrs)
+{
+ unsigned int i = 0;
+ bool keep_all = false;
+ unsigned int num_del = 0;
+
+ if (attrs) {
+ /* check for special attrs */
+ for (i = 0; attrs[i]; i++) {
+ int cmp = strcmp(attrs[i], "*");
+ if (cmp == 0) {
+ keep_all = true;
+ break;
+ }
+ }
+ if (!keep_all && i == 0) {
+ msg->num_elements = 0;
+ return LDB_SUCCESS;
+ }
+ } else {
+ keep_all = true;
+ }
+
+ for (i = 0; i < msg->num_elements; i++) {
+ bool found = false;
+ unsigned int j;
+
+ if (keep_all) {
+ found = true;
+ } else {
+ for (j = 0; attrs[j]; j++) {
+ int cmp = ldb_attr_cmp(msg->elements[i].name, attrs[j]);
+ if (cmp == 0) {
+ found = true;
+ break;
+ }
+ }
+ }
+
+ if (!found) {
+ ++num_del;
+ } else if (num_del != 0) {
+ msg->elements[i - num_del] = msg->elements[i];
+ }
+ }
+
+ msg->num_elements -= num_del;
+
+ return LDB_SUCCESS;
+}
+
+/* Have an unpacked ldb message take talloc ownership of its elements. */
+int ldb_msg_elements_take_ownership(struct ldb_message *msg)
+{
+ unsigned int i = 0;
+
+ for (i = 0; i < msg->num_elements; i++) {
+ struct ldb_message_element *el = &msg->elements[i];
+ const char *name;
+ unsigned int j;
+
+ name = talloc_strdup(msg->elements,
+ el->name);
+ if (name == NULL) {
+ return -1;
+ }
+ el->name = name;
+
+ if (el->flags & LDB_FLAG_INTERNAL_SHARED_VALUES) {
+ struct ldb_val *values = talloc_memdup(msg->elements, el->values,
+ sizeof(struct ldb_val) * el->num_values);
+ if (values == NULL) {
+ return -1;
+ }
+ el->values = values;
+ el->flags &= ~LDB_FLAG_INTERNAL_SHARED_VALUES;
+ }
+
+ for (j = 0; j < el->num_values; j++) {
+ struct ldb_val val = ldb_val_dup(el->values, &el->values[j]);
+ if (val.data == NULL && el->values[j].length != 0) {
+ return -1;
+ }
+ el->values[j] = val;
+ }
+ }
+
+ return LDB_SUCCESS;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 19:01:11 +0000