static void
dissect_v8_message_data(tvbuff_t *message_tvb, packet_info *pinfo, proto_item *m2pa_item, proto_tree *m2pa_tree, proto_tree *tree)
{
guint32 message_data_length;
guint8 type;
tvbuff_t *message_data_tvb;
message_data_length = tvb_get_ntohl(message_tvb, V8_LENGTH_OFFSET) - V8_HEADER_LENGTH;
if ((gint) message_data_length < 1) {
if (m2pa_tree)
proto_tree_add_text(m2pa_tree, message_tvb, V8_LENGTH_OFFSET, 4,
"Invalid message data length: %u", message_data_length);
THROW(ReportedBoundsError);
}
message_data_tvb = tvb_new_subset(message_tvb, V8_MESSAGE_DATA_OFFSET, message_data_length, message_data_length);
type = tvb_get_guint8(message_tvb, V8_TYPE_OFFSET);
switch(type) {
case V8_USER_DATA_TYPE:
dissect_v8_user_data_message(message_data_tvb, pinfo, m2pa_item, m2pa_tree, tree);
break;
case V8_LINK_STATUS_TYPE:
dissect_v8_link_status_message(message_data_tvb, pinfo, m2pa_tree);
break;
default:
dissect_unknown_message(message_data_tvb, m2pa_tree);
}
}
static void
dissect_v2_message_data(tvbuff_t *message_tvb, packet_info *pinfo, proto_item *m2pa_item, proto_tree *m2pa_tree, proto_tree *tree)
{
guint32 message_data_length;
guint16 type;
tvbuff_t *message_data_tvb;
message_data_length = (gint) tvb_get_ntohl(message_tvb, V2_LENGTH_OFFSET);
if ((gint) message_data_length < 1) {
proto_tree_add_expert_format(m2pa_tree, pinfo, &ei_length, message_tvb, V2_LENGTH_OFFSET, 4,
"Invalid message data length: %u", message_data_length);
return;
}
message_data_tvb = tvb_new_subset_length(message_tvb, V2_MESSAGE_DATA_OFFSET, message_data_length);
type = tvb_get_ntohs(message_tvb, V2_TYPE_OFFSET);
switch(type) {
case V2_USER_DATA_TYPE:
dissect_v2_user_data_message(message_data_tvb, pinfo, m2pa_item, m2pa_tree, tree);
break;
case V2_LINK_STATUS_TYPE:
dissect_v2_link_status_message(message_data_tvb, pinfo, m2pa_tree);
break;
default:
dissect_unknown_message(message_data_tvb, m2pa_tree);
}
}
static void
dissect_v8_message_data(tvbuff_t *message_tvb, packet_info *pinfo, proto_item *m2pa_item, proto_tree *m2pa_tree, proto_tree *tree)
{
guint32 message_data_length;
guint8 type;
tvbuff_t *message_data_tvb;
message_data_length = tvb_get_ntohl(message_tvb, V8_LENGTH_OFFSET) - V8_HEADER_LENGTH;
if ((gint) message_data_length < 1) {
proto_tree_add_expert_format(m2pa_tree, pinfo, &ei_length, message_tvb, V8_LENGTH_OFFSET, 4,
"Invalid message data length: %u", message_data_length);
/* XXX - is this really necessary? Can we just return since the expert info can
still find the "malformed" packet? */
THROW(ReportedBoundsError);
}
message_data_tvb = tvb_new_subset_length(message_tvb, V8_MESSAGE_DATA_OFFSET, message_data_length);
type = tvb_get_guint8(message_tvb, V8_TYPE_OFFSET);
switch(type) {
case V8_USER_DATA_TYPE:
dissect_v8_user_data_message(message_data_tvb, pinfo, m2pa_item, m2pa_tree, tree);
break;
case V8_LINK_STATUS_TYPE:
dissect_v8_link_status_message(message_data_tvb, pinfo, m2pa_tree);
break;
default:
dissect_unknown_message(message_data_tvb, m2pa_tree);
}
}
static void
dissect_v12_message_data(tvbuff_t *message_tvb, packet_info *pinfo, proto_item *m2pa_item, proto_tree *m2pa_tree, proto_tree *tree)
{
guint32 message_data_length;
guint8 type;
tvbuff_t *message_data_tvb;
message_data_length = tvb_get_ntohl(message_tvb, V12_LENGTH_OFFSET) - V8_HEADER_LENGTH;
message_data_tvb = tvb_new_subset(message_tvb, V12_MESSAGE_DATA_OFFSET, message_data_length, message_data_length);
type = tvb_get_guint8(message_tvb, V12_TYPE_OFFSET);
switch(type) {
case V12_USER_DATA_TYPE:
dissect_v12_user_data_message(message_data_tvb, pinfo, m2pa_item, m2pa_tree, tree);
break;
case V12_LINK_STATUS_TYPE:
dissect_v12_link_status_message(message_data_tvb, pinfo, m2pa_tree);
break;
default:
dissect_unknown_message(message_data_tvb, m2pa_tree);
}
}
static void
dissect_message_data(tvbuff_t *message_tvb, packet_info *pinfo, proto_item *m2pa_item, proto_tree *m2pa_tree, proto_tree *tree)
{
guint32 length, message_data_length, actual_length;
guint8 type;
tvbuff_t *message_data_tvb;
length = tvb_get_ntohl(message_tvb, LENGTH_OFFSET);
message_data_length = length - HEADER_LENGTH;
message_data_tvb = tvb_new_subset(message_tvb, MESSAGE_DATA_OFFSET, message_data_length, message_data_length);
type = tvb_get_guint8(message_tvb, TYPE_OFFSET);
switch(type) {
case USER_DATA_TYPE:
dissect_user_data_message(message_data_tvb, pinfo, m2pa_item, m2pa_tree, tree);
break;
case LINK_STATUS_TYPE:
dissect_link_status_message(message_data_tvb, pinfo, m2pa_tree);
break;
default:
dissect_unknown_message(message_data_tvb, m2pa_tree);
}
actual_length = tvb_reported_length(message_tvb);
if (actual_length > length)
{
proto_item *pi;
pi = proto_tree_add_item(m2pa_tree, hf_undecode_data, message_tvb, length, (actual_length - length), ENC_NA);
expert_add_info_format(pinfo, pi, PI_MALFORMED, PI_WARN,
"There are %d bytes of data which is greater than M2PA's length parameter (%d)",
actual_length, length);
}
}
