Secure the BVLC decoders by replacing deprecated primitive and complex data decoders. (#1241)

This commit is contained in:
Steve Karg
2026-02-20 10:30:46 -06:00
committed by GitHub
parent 7d78889aa9
commit 578f507125
3 changed files with 44 additions and 94 deletions
+29 -94
View File
@@ -670,129 +670,64 @@ int bvlc_broadcast_distribution_table_encode(
/**
* @brief Decode the Broadcast-Distribution-Table for Network Port object
* @param apdu - the APDU buffer
* @param apdu_len - the APDU buffer length
* @param apdu_size - the APDU buffer length
* @param bdt_head - head of a BDT linked list
* @return length of the APDU buffer decoded, or ERROR, REJECT, or ABORT
*/
int bvlc_broadcast_distribution_table_decode(
const uint8_t *apdu,
uint16_t apdu_len,
uint16_t apdu_size,
BACNET_ERROR_CODE *error_code,
BACNET_IP_BROADCAST_DISTRIBUTION_TABLE_ENTRY *bdt_head)
{
int len = 0;
BACNET_OCTET_STRING octet_string = { 0 };
int len = 0, apdu_len = 0;
BACNET_IP_BROADCAST_DISTRIBUTION_TABLE_ENTRY *bdt_entry = NULL;
uint8_t tag_number = 0;
uint32_t len_value_type = 0;
BACNET_UNSIGNED_INTEGER unsigned_value = 0;
BACNET_HOST_N_PORT_MINIMAL host_n_port = { 0 };
/* default reject code */
if (error_code) {
*error_code = ERROR_CODE_REJECT_MISSING_REQUIRED_PARAMETER;
}
/* check for value pointers */
if ((apdu_len == 0) || (!apdu)) {
if ((apdu_size == 0) || (!apdu)) {
return BACNET_STATUS_REJECT;
}
bdt_entry = bdt_head;
while (bdt_entry) {
/* bbmd-address [0] BACnetHostNPort - opening */
if (!decode_is_opening_tag_number(&apdu[len++], 0)) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
len = host_n_port_minimal_context_decode(
&apdu[apdu_len], apdu_size - apdu_len, 0, error_code, &host_n_port);
if (len > 0) {
apdu_len += len;
bdt_entry->dest_address.port = host_n_port.port;
if (host_n_port.tag == BACNET_HOST_ADDRESS_TAG_IP_ADDRESS) {
bdt_entry->valid = true;
bdt_entry->dest_address.address[0] =
host_n_port.host.ip_address.address[0];
bdt_entry->dest_address.address[1] =
host_n_port.host.ip_address.address[1];
bdt_entry->dest_address.address[2] =
host_n_port.host.ip_address.address[2];
bdt_entry->dest_address.address[3] =
host_n_port.host.ip_address.address[3];
} else {
bdt_entry->valid = false;
}
return BACNET_STATUS_REJECT;
}
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
/* host [0] BACnetHostAddress - opening */
if (!decode_is_opening_tag_number(&apdu[len++], 0)) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
/* CHOICE - ip-address [1] OCTET STRING */
len += decode_tag_number_and_value(
&apdu[len], &tag_number, &len_value_type);
if (tag_number != 1) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
len += decode_octet_string(&apdu[len], len_value_type, &octet_string);
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
(void)octetstring_copy_value(
&bdt_entry->dest_address.address[0], IP_ADDRESS_MAX, &octet_string);
/* host [0] BACnetHostAddress - closing */
if (!decode_is_closing_tag_number(&apdu[len++], 0)) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
/* port [1] Unsigned16 */
len += decode_tag_number_and_value(
&apdu[len], &tag_number, &len_value_type);
if (tag_number != 1) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
len += decode_unsigned(&apdu[len], len_value_type, &unsigned_value);
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
if (unsigned_value <= UINT16_MAX) {
bdt_entry->dest_address.port = unsigned_value;
} else {
if (error_code) {
*error_code = ERROR_CODE_REJECT_PARAMETER_OUT_OF_RANGE;
}
return BACNET_STATUS_REJECT;
}
/* bbmd-address [0] BACnetHostNPort - closing */
if (!decode_is_closing_tag_number(&apdu[len++], 0)) {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
/* broadcast-mask [1] OCTET STRING */
len += decode_tag_number_and_value(
&apdu[len], &tag_number, &len_value_type);
if (tag_number != 1) {
len = bacnet_octet_string_buffer_context_decode(
&apdu[apdu_len], apdu_size - apdu_len, 1,
bdt_entry->broadcast_mask.address,
sizeof(bdt_entry->broadcast_mask.address));
if (len > 0) {
apdu_len += len;
} else {
if (error_code) {
*error_code = ERROR_CODE_REJECT_INVALID_TAG;
}
return BACNET_STATUS_REJECT;
}
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
len += decode_octet_string(&apdu[len], len_value_type, &octet_string);
if (len > apdu_len) {
return BACNET_STATUS_REJECT;
}
(void)octetstring_copy_value(
&bdt_entry->broadcast_mask.address[0], IP_ADDRESS_MAX,
&octet_string);
bdt_entry->valid = true;
/* next entry */
bdt_entry = bdt_entry->next;
}