osmocom
/
wireshark
11
0
Fork 1
Code Issues Pull Requests Projects Releases Wiki Activity

MQTT v5 malformed packet fixes. 

PUBACK, PUBREC, PUBREL, and PUBCOMP can all have abbreviated packets
which are not currently handled, leading to those forms being marked as
malformed.

Bug: 15428
Change-Id: I1e6e5dbbca29e7e731683d5c166f9abf978f62b2
Reviewed-on: https://code.wireshark.org/review/31580
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
This commit is contained in:
Roger Light 2019-01-17 19:06:24 +00:00 committed by Anders Broman
parent 362be299d0
commit 10bcb40c5e
1 changed files with 12 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
epan/dissectors/packet-mqtt.c
View File

@ -1205,12 +1205,22 @@ static int dissect_mqtt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, voi
offset += 2;
col_append_fstr(pinfo->cinfo, COL_INFO, " (id=%u)", mqtt_msgid);
if (mqtt->runtime_proto_version == MQTT_PROTO_V50)
/* MQTT v5.0: The Reason Code and Property Length can be omitted if the
* Reason Code is 0x00 and there are no Properties.
* In this case, the PUB* has a Remaining Length of 2.
*/
if (mqtt->runtime_proto_version == MQTT_PROTO_V50 && mqtt_msg_len > 2)
{
dissect_mqtt_reason_code(mqtt_tree, tvb, offset, mqtt_msg_type);
offset += 1;
offset += dissect_mqtt_properties(tvb, mqtt_tree, offset, hf_mqtt_property);
/* If the Remaining Length is less than 4, the Property Length is not
* present and has a value of 0.
*/
if (mqtt_msg_len > 3)
{
offset += dissect_mqtt_properties(tvb, mqtt_tree, offset, hf_mqtt_property);
}
}
break;