diff options
| author | Valentin Vidic <Valentin.Vidic@CARNet.hr> | 2018-02-19 12:10:03 +0100 |
|---|---|---|
| committer | Anders Broman <a.broman58@gmail.com> | 2018-02-19 15:48:56 +0000 |
| commit | 70608effe4d23bb5f05dc783b21c1ab9d2e5aa66 (patch) | |
| tree | 6dba8dbfa05835baadcbd0265a2889528924edd4 | |
| parent | 8da569b6ad5beb9fa8c6aa49279e8a805ffbdfda (diff) | |
TWAMP: Handle short TWAMP-Test packets
Requests packets have a minimum length of 14 bytes and only
responses have additional 27 bytes of fields. Without this
patch short packets generate an exception and get reported
as malformed.
Change-Id: If75fa5556059b13f40fc49273edcbd32508fa0fc
Reviewed-on: https://code.wireshark.org/review/25897
Petri-Dish: Alexis La Goutte <alexis.lagoutte@gmail.com>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>
| -rw-r--r-- | epan/dissectors/packet-twamp.c | 31 |
1 files changed, 17 insertions, 14 deletions
diff --git a/epan/dissectors/packet-twamp.c b/epan/dissectors/packet-twamp.c index cec61bcd45..9497f447ad 100644 --- a/epan/dissectors/packet-twamp.c +++ b/epan/dissectors/packet-twamp.c @@ -553,23 +553,26 @@ dissect_twamp_test(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *da proto_tree_add_bitmask(twamp_tree, tvb, offset, hf_twamp_error_estimate, ett_twamp_error_estimate, twamp_error_estimate_flags, ENC_BIG_ENDIAN); offset += 2; - proto_tree_add_item (twamp_tree, hf_twamp_mbz1, tvb, offset, 2, ENC_BIG_ENDIAN); - offset += 2; - proto_tree_add_item(twamp_tree, hf_twamp_receive_timestamp, tvb, offset, 8, ENC_TIME_NTP | ENC_BIG_ENDIAN); - offset += 8; + /* Responder sends TWAMP-Test packets with additional fields */ + if (tvb_reported_length(tvb) - offset >= 27) { + proto_tree_add_item (twamp_tree, hf_twamp_mbz1, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + proto_tree_add_item(twamp_tree, hf_twamp_receive_timestamp, tvb, offset, 8, ENC_TIME_NTP | ENC_BIG_ENDIAN); + offset += 8; - proto_tree_add_item (twamp_tree, hf_twamp_sender_seq_number, tvb, offset, 4, ENC_BIG_ENDIAN); - offset += 4; + proto_tree_add_item (twamp_tree, hf_twamp_sender_seq_number, tvb, offset, 4, ENC_BIG_ENDIAN); + offset += 4; - proto_tree_add_item(twamp_tree, hf_twamp_sender_timestamp, tvb, offset, 8, ENC_TIME_NTP | ENC_BIG_ENDIAN); - offset += 8; + proto_tree_add_item(twamp_tree, hf_twamp_sender_timestamp, tvb, offset, 8, ENC_TIME_NTP | ENC_BIG_ENDIAN); + offset += 8; - proto_tree_add_item (twamp_tree, hf_twamp_sender_error_estimate, tvb, offset, 2, ENC_BIG_ENDIAN); - offset += 2; - proto_tree_add_item (twamp_tree, hf_twamp_mbz2, tvb, offset, 2, ENC_BIG_ENDIAN); - offset += 2; - proto_tree_add_item (twamp_tree, hf_twamp_sender_ttl, tvb, offset, 1, ENC_BIG_ENDIAN); - offset += 1; + proto_tree_add_item (twamp_tree, hf_twamp_sender_error_estimate, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + proto_tree_add_item (twamp_tree, hf_twamp_mbz2, tvb, offset, 2, ENC_BIG_ENDIAN); + offset += 2; + proto_tree_add_item (twamp_tree, hf_twamp_sender_ttl, tvb, offset, 1, ENC_BIG_ENDIAN); + offset += 1; + } padding = tvb_reported_length(tvb) - offset; if (padding > 0) { |