diff options
| author | Martin Kaiser <wireshark@kaiser.cx> | 2018-12-08 15:30:26 +0100 |
|---|---|---|
| committer | Jaap Keuter <jaap.keuter@xs4all.nl> | 2018-12-08 16:35:16 +0000 |
| commit | ac4c11f26eb5544788d08c918252da6c4b1b0b43 (patch) | |
| tree | 123cd2fb6cd36361b4f01aa45d8062f9722e84aa /epan/dissectors/packet-cattp.c | |
| parent | a02d592c76fb1430eff0b1bc7a4a45d39ac4e9eb (diff) | |
cattp: use the version bits in the heristic check
The CAT-TP specification says explicitly that the version bits must be
zero. Fail the heuristic check if they aren't.
I checked ETSI TS 102 127 V15.0.0 from
https://www.etsi.org/deliver/etsi_ts/102100_102199/102127/15.00.00_60/ts_102127v150000p.pdf
Bug: 15342
Change-Id: I05a886ccd5811f367abdb9faead4983d137c12c6
Reviewed-on: https://code.wireshark.org/review/30970
Reviewed-by: Martin Kaiser <wireshark@kaiser.cx>
Petri-Dish: Martin Kaiser <wireshark@kaiser.cx>
Tested-by: Petri Dish Buildbot
Reviewed-by: Jaap Keuter <jaap.keuter@xs4all.nl>
Diffstat (limited to 'epan/dissectors/packet-cattp.c')
| -rw-r--r-- | epan/dissectors/packet-cattp.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/epan/dissectors/packet-cattp.c b/epan/dissectors/packet-cattp.c index f000a739e7..6be847104d 100644 --- a/epan/dissectors/packet-cattp.c +++ b/epan/dissectors/packet-cattp.c @@ -321,7 +321,7 @@ static gboolean dissect_cattp_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) { if (tvb_captured_length(tvb) >= CATTP_HBLEN) { /* check of data is big enough for base header. */ - guint8 flags, hlen; + guint8 flags, ver, hlen; guint16 plen; hlen = tvb_get_guint8(tvb, 3); /* header len */ @@ -330,6 +330,12 @@ dissect_cattp_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *da if (hlen+plen != tvb_reported_length(tvb)) /* check if data length is ok. */ return FALSE; + /* ETSI TS 102 127 V15.0.0 and earlier releases say explicitly that + the version bits must be 0. */ + ver = tvb_get_guint8(tvb, 0) & M_VERSION; + if (ver != 0) + return FALSE; + flags = tvb_get_guint8(tvb, 0) & M_FLAGS; if ( (flags & M_PDU_SYN) == F_SYN || (flags & M_PDU_RST) == F_RST || |