forked from osmocom/wireshark
![Michael Mann](/assets/img/avatar_default.png)
This saves many dissectors the need to find the data dissector and store a handle to it. There were also some that were finding it, but not using it. For others this was the only reason for their handoff function, so it could be eliminated. Change-Id: I5d3f951ee1daa3d30c060d21bd12bbc881a8027b Reviewed-on: https://code.wireshark.org/review/14530 Petri-Dish: Michael Mann <mmann78@netscape.net> Reviewed-by: Michael Mann <mmann78@netscape.net>
785 lines
21 KiB
C
785 lines
21 KiB
C
/* packet-lapsat.c
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*
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* Routines for GMR-1 LAPSat dissection in wireshark.
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*
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* Link Access Procedures (LAP) for the Satellite Channel (LAPSat).
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* LAPSat is the protocol for signalling transfer between an Access
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* Terminal (MES) and a Gateway Station (GS) in the GeoMobile (GMR-1) network.
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*
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* Copyright (c) 2011 Sylvain Munaut <tnt@246tNt.com>
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* Inspired on LAPDm code by Duncan Salerno <duncan.salerno@googlemail.com>
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*
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* References:
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* [1] ETSI TS 101 376-4-6 V1.2.1 - GMR-1 04.006
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include "config.h"
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#include <epan/packet.h>
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#include <epan/reassemble.h>
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void proto_register_lapsat(void);
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static int proto_lapsat = -1;
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static reassembly_table lapsat_reassembly_table;
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static dissector_table_t lapsat_sapi_dissector_table;
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static gint ett_lapsat = -1;
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static gint ett_lapsat_address = -1;
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static gint ett_lapsat_control = -1;
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static gint ett_lapsat_fragment = -1;
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static gint ett_lapsat_fragments = -1;
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static int hf_lapsat_addr = -1;
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static int hf_lapsat_addr_sst = -1;
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static int hf_lapsat_addr_cr = -1;
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static int hf_lapsat_addr_sapi = -1;
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static int hf_lapsat_addr_si = -1;
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static int hf_lapsat_addr_lpd = -1;
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static int hf_lapsat_addr_lfi = -1;
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static int hf_lapsat_ctl = -1;
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static int hf_lapsat_ctl_ftype_i = -1;
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static int hf_lapsat_ctl_ftype_s_u = -1;
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static int hf_lapsat_ctl_s_ftype = -1;
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static int hf_lapsat_ctl_u_modifier_cmd = -1;
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static int hf_lapsat_ctl_u_modifier_resp = -1;
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static int hf_lapsat_ctl_n_r = -1;
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static int hf_lapsat_ctl_n_s = -1;
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static int hf_lapsat_ctl_p = -1;
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static int hf_lapsat_ctl_f = -1;
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static int hf_lapsat_ctl_mii = -1;
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static int hf_lapsat_payload_last_nibble = -1;
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static int hf_lapsat_len = -1;
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static int hf_lapsat_fragment_data = -1;
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static int hf_lapsat_fragments = -1;
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static int hf_lapsat_fragment = -1;
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static int hf_lapsat_fragment_overlap = -1;
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static int hf_lapsat_fragment_overlap_conflicts = -1;
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static int hf_lapsat_fragment_multiple_tails = -1;
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static int hf_lapsat_fragment_too_long_fragment = -1;
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static int hf_lapsat_fragment_error = -1;
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static int hf_lapsat_fragment_count = -1;
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static int hf_lapsat_reassembled_in = -1;
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static int hf_lapsat_reassembled_length = -1;
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#define LAPSAT_HEADER_LEN 3
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#define LAPSAT_SAPI_RR_CC_MM 0
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#define LAPSAT_SAPI_SMS 3
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/*
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* Address field bits
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*/
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#define LAPSAT_SST 0x01 /* SACCH status bit */
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#define LAPSAT_CR 0x02 /* Command/Response bit */
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#define LAPSAT_SAPI_MSK 0x0c /* Service Access Point Identifier */
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#define LAPSAT_SAPI_SHIFT 2
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#define LAPSAT_SI 0x10 /* Segment Indicator */
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#define LAPSAT_LPD_MSK 0x60 /* DL for LAPSat or SMS-CB */
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#define LAPSAT_LPD_SHIFT 6
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#define LAPSAT_LFI 0x80 /* Length Field Indicator */
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static const value_string lapsat_addr_sst_vals[] = {
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{ 0, "FACCH and all other messages" },
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{ 1, "SACCH message" },
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{ 0 , NULL }
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};
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static const value_string lapsat_addr_sapi_vals[] = {
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{ LAPSAT_SAPI_RR_CC_MM, "RR/MM/CC" },
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{ LAPSAT_SAPI_SMS, "SMS/SS" },
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{ 0, NULL }
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};
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static const value_string lapsat_addr_lpd_vals[] = {
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{ 0, "Normal GMR-1" },
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{ 1, "Cell broadcast service" },
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{ 0, NULL }
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};
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static const value_string lapsat_addr_si_vals[] = {
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{ 0, "Complete/Last Segment of L3 message" },
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{ 1, "Segment only" },
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{ 0, NULL }
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};
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static const value_string lapsat_addr_lfi_vals[] = {
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{ 0, "Length Field not present (all data valid)" },
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{ 1, "Length Field present" },
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{ 0, NULL }
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};
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/*
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* Frame types
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*/
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#define LAPSAT_CTL_TYPE_S 0x001
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#define LAPSAT_CTL_TYPE_U 0x003
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#define LAPSAT_CTL_TYPE_S_U_MSK 0x003
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#define LAPSAT_CTL_TYPE_I 0x000
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#define LAPSAT_CTL_TYPE_I_MSK 0x001
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static const value_string lapsat_ctl_ftype_vals[] = {
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{ LAPSAT_CTL_TYPE_I, "Information frame" },
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{ LAPSAT_CTL_TYPE_S, "Supervisory frame" },
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{ LAPSAT_CTL_TYPE_U, "Unnumbered frame" },
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{ 0, NULL }
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};
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/*
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* S-format frame types
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*/
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#define LAPSAT_CTL_S_FTYPE_MSK 0x00c
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#define LAPSAT_RR 0x000
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#define LAPSAT_GREJ 0x008
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static const value_string lapsat_ctl_s_ftype_vals[] = {
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{ LAPSAT_RR >> 2, "Receiver ready" },
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{ LAPSAT_GREJ >> 2, "Group reject" },
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{ 0, NULL}
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};
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/*
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* U-format modifiers
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*/
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#define LAPSAT_CTL_U_MODIFIER_MSK 0x18c
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#define LAPSAT_SABM 0x08c
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#define LAPSAT_DM 0x00c
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#define LAPSAT_DISC 0x100
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#define LAPSAT_UA 0x180
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#define LAPSAT_UI 0x000
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static const value_string lapsat_ctl_u_modifier_vals_cmd[] = {
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{ LAPSAT_SABM >> 2, "Set Asynchronous Balanced Mode" },
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{ LAPSAT_DISC >> 2, "Disconnect" },
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{ LAPSAT_UI >> 2, "Unnumbered Information" },
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{ 0, NULL}
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};
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static const value_string lapsat_ctl_u_modifier_vals_resp[] = {
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{ LAPSAT_DM >> 2, "Disconnected mode" },
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{ LAPSAT_UA >> 2, "Unnumbered Acknowledge" },
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{ 0, NULL}
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};
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/*
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* Control fields
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*/
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#define LAPSAT_CTL_P_F 0x040
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#define LAPSAT_CTL_MII 0x200
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#define LAPSAT_CTL_N_R_MSK 0xf80
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#define LAPSAT_CTL_N_R_SHIFT 7
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#define LAPSAT_CTL_N_S_MSK 0x03e
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#define LAPSAT_CTL_N_S_SHIFT 1
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/*
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* Fragment stuff
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*/
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static const value_string true_false_vals[] = {
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{ 0, "False" },
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{ 1, "True" },
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{ 0, NULL },
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};
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static const fragment_items lapsat_frag_items = {
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/* Fragment subtrees */
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&ett_lapsat_fragment,
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&ett_lapsat_fragments,
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/* Fragment fields */
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&hf_lapsat_fragments,
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&hf_lapsat_fragment,
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&hf_lapsat_fragment_overlap,
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&hf_lapsat_fragment_overlap_conflicts,
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&hf_lapsat_fragment_multiple_tails,
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&hf_lapsat_fragment_too_long_fragment,
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&hf_lapsat_fragment_error,
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&hf_lapsat_fragment_count,
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/* Reassembled in field */
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&hf_lapsat_reassembled_in,
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/* Reassembled length field */
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&hf_lapsat_reassembled_length,
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/* Reassembled data field */
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NULL,
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/* Tag */
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"fragments"
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};
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static void
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lapsat_defragment_init(void)
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{
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reassembly_table_init(&lapsat_reassembly_table,
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&addresses_reassembly_table_functions);
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}
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static void
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lapsat_defragment_cleanup(void)
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{
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reassembly_table_destroy(&lapsat_reassembly_table);
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}
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/*
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* Main dissection functions
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*/
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static guint16
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dissect_control(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int is_response)
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{
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proto_tree *ctl_tree;
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proto_item *ctl_ti;
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guint16 ctl, poll_final;
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const char *frame_type;
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char *info;
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info = (char *)wmem_alloc(wmem_packet_scope(), 80);
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/* Grab complete control field */
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ctl = tvb_get_ntohs(tvb, 1) >> 4;
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poll_final = ctl & LAPSAT_CTL_P_F;
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/* Generate small 'descriptive' text */
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switch (ctl & LAPSAT_CTL_TYPE_S_U_MSK) {
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case LAPSAT_CTL_TYPE_S:
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/*
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* Supervisory frame.
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*/
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switch (ctl & LAPSAT_CTL_S_FTYPE_MSK) {
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case LAPSAT_RR:
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frame_type = "RR";
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break;
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case LAPSAT_GREJ:
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frame_type = "GREJ";
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break;
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default:
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frame_type = "Unknown";
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break;
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}
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g_snprintf(info, 80, "S%s, func=%s, N(R)=%u",
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poll_final ? (is_response ? " F" : " P") : "",
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frame_type,
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(ctl & LAPSAT_CTL_N_R_MSK) >> LAPSAT_CTL_N_R_SHIFT);
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break;
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case LAPSAT_CTL_TYPE_U:
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/*
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* Unnumbered frame
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*/
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switch (ctl & LAPSAT_CTL_U_MODIFIER_MSK) {
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case LAPSAT_SABM:
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frame_type = (ctl & LAPSAT_CTL_MII) ?
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"SABM, MII=1" : "SABM, MII=0";
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break;
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case LAPSAT_DM:
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frame_type = "DM";
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break;
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case LAPSAT_DISC:
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frame_type = "DISC";
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break;
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case LAPSAT_UA:
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frame_type = "UA";
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break;
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case LAPSAT_UI:
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frame_type = "UI";
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break;
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default:
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frame_type = "Unknown";
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break;
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}
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g_snprintf(info, 80, "U%s, func=%s",
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poll_final ? (is_response ? " F" : " P") : "",
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frame_type);
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break;
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default:
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/*
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* Information frame
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*/
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g_snprintf(info, 80, "I%s, N(R)=%u, N(S)=%u",
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poll_final ? " P" : "",
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(ctl & LAPSAT_CTL_N_R_MSK) >> LAPSAT_CTL_N_R_SHIFT,
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(ctl & LAPSAT_CTL_N_S_MSK) >> LAPSAT_CTL_N_S_SHIFT);
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break;
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}
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/* Add info */
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col_add_str(pinfo->cinfo, COL_INFO, info);
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/* Create item & subtree */
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ctl_ti = proto_tree_add_uint_format_value(
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tree, hf_lapsat_ctl,
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tvb, 1, 2, (guint32)ctl,
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"%s (0x%03x)", info, ctl
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);
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ctl_tree = proto_item_add_subtree(ctl_ti, ett_lapsat_control);
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/* Add all fields */
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switch (ctl & LAPSAT_CTL_TYPE_S_U_MSK) {
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case LAPSAT_CTL_TYPE_S:
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/*
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* Supervisory frame.
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*/
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_ftype_s_u,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_s_ftype,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_n_r,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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if (poll_final)
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proto_tree_add_item(ctl_tree,
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is_response ? hf_lapsat_ctl_f : hf_lapsat_ctl_p,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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break;
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case LAPSAT_CTL_TYPE_U:
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/*
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* Unnumbered frame
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*/
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_ftype_s_u,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(ctl_tree,
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is_response ? hf_lapsat_ctl_u_modifier_resp :
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hf_lapsat_ctl_u_modifier_cmd,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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if (poll_final)
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proto_tree_add_item(ctl_tree,
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is_response ? hf_lapsat_ctl_f : hf_lapsat_ctl_p,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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if (((ctl & LAPSAT_CTL_U_MODIFIER_MSK) == LAPSAT_SABM) &&
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(ctl & LAPSAT_CTL_MII))
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_mii,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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break;
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default:
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/*
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* Information frame
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*/
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_ftype_i,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_n_r,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_n_s,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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if (poll_final)
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proto_tree_add_item(ctl_tree, hf_lapsat_ctl_p,
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tvb, 1, 2, ENC_BIG_ENDIAN);
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break;
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}
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return ctl;
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}
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static int
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dissect_lapsat(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* dissector_data _U_)
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{
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proto_tree *lapsat_tree, *addr_tree;
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proto_item *lapsat_ti, *addr_ti;
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tvbuff_t *payload;
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guint8 addr, sapi, cr;
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guint16 control;
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unsigned int hlen, is_response = 0, plen;
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/* Check that there's enough data */
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if (tvb_captured_length(tvb) < LAPSAT_HEADER_LEN)
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return 0;
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/* Set protocol column */
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "LAPSat");
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/* Grab a couple of fields */
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addr = tvb_get_guint8(tvb, 0);
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sapi = (addr & LAPSAT_SAPI_MSK) >> LAPSAT_SAPI_SHIFT;
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cr = addr & LAPSAT_CR;
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if (pinfo->p2p_dir == P2P_DIR_RECV) {
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is_response = cr ? FALSE : TRUE;
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}
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else if (pinfo->p2p_dir == P2P_DIR_SENT) {
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is_response = cr ? TRUE : FALSE;
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}
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hlen = LAPSAT_HEADER_LEN;
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if (addr & LAPSAT_LFI)
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hlen++;
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/* FIXME if "S func=GREJ", extend */
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/* Create LAPSat tree */
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lapsat_ti = proto_tree_add_item(tree, proto_lapsat, tvb, 0, hlen, ENC_NA);
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lapsat_tree = proto_item_add_subtree(lapsat_ti, ett_lapsat);
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/* Dissect address field */
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addr_ti = proto_tree_add_item(lapsat_tree, hf_lapsat_addr, tvb, 0, 1, ENC_BIG_ENDIAN);
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addr_tree = proto_item_add_subtree(addr_ti, ett_lapsat_address);
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proto_tree_add_item(addr_tree, hf_lapsat_addr_sst, tvb, 0, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(addr_tree, hf_lapsat_addr_cr, tvb, 0, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(addr_tree, hf_lapsat_addr_sapi, tvb, 0, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(addr_tree, hf_lapsat_addr_si, tvb, 0, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(addr_tree, hf_lapsat_addr_lpd, tvb, 0, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(addr_tree, hf_lapsat_addr_lfi, tvb, 0, 1, ENC_BIG_ENDIAN);
|
|
|
|
/* Dissect control field */
|
|
control = dissect_control(tvb, pinfo, lapsat_tree, is_response);
|
|
|
|
/* Last payload nibble */
|
|
proto_tree_add_item(lapsat_tree, hf_lapsat_payload_last_nibble, tvb, 2, 1, ENC_BIG_ENDIAN);
|
|
|
|
/* Optional length field */
|
|
if (addr & LAPSAT_LFI)
|
|
proto_tree_add_item(lapsat_tree, hf_lapsat_len, tvb, 3, 1, ENC_BIG_ENDIAN);
|
|
|
|
/* If frame is "S func=GREJ", then add Na(R) & Nb(R) */
|
|
/* FIXME */
|
|
|
|
/* Get the payload */
|
|
plen = (addr & LAPSAT_LFI) ?
|
|
tvb_get_guint8(tvb, 3) : tvb_captured_length(tvb) - hlen;
|
|
|
|
if (!plen)
|
|
return 3; /* No point in doing more if there is no payload */
|
|
|
|
DISSECTOR_ASSERT((plen + hlen) <= tvb_captured_length(tvb));
|
|
|
|
if ((plen + hlen) == tvb_captured_length(tvb)) {
|
|
/* Need to integrate the last nibble */
|
|
guint8 *data = (guint8 *)tvb_memdup(NULL, tvb, hlen, plen);
|
|
data[plen-1] |= tvb_get_guint8(tvb, 2) << 4;
|
|
payload = tvb_new_child_real_data(tvb, data, plen, plen);
|
|
tvb_set_free_cb(payload, g_free);
|
|
} else {
|
|
/* Last nibble doesn't need merging */
|
|
payload = tvb_new_subset(tvb, hlen, plen, -1);
|
|
}
|
|
|
|
add_new_data_source(pinfo, payload, "LAPSat Payload");
|
|
|
|
/* Handle fragments */
|
|
if ((control & LAPSAT_CTL_TYPE_I_MSK) == LAPSAT_CTL_TYPE_I) {
|
|
/*
|
|
* Potentially fragmented I frames
|
|
*/
|
|
fragment_head *fd_m = NULL;
|
|
tvbuff_t *reassembled = NULL;
|
|
guint32 fragment_id;
|
|
gboolean save_fragmented = pinfo->fragmented;
|
|
|
|
/* Is this a fragment ? */
|
|
pinfo->fragmented = !!(addr & LAPSAT_SI);
|
|
|
|
/* Rely on caller to provide a way to group fragments */
|
|
fragment_id = (pinfo->circuit_id << 3) | (sapi << 1) | pinfo->p2p_dir;
|
|
|
|
/* Fragment reconstruction helpers */
|
|
fd_m = fragment_add_seq_next(
|
|
&lapsat_reassembly_table,
|
|
payload, 0,
|
|
pinfo,
|
|
fragment_id, /* To group fragments */
|
|
NULL,
|
|
plen,
|
|
!!(addr & LAPSAT_SI) /* More fragment ? */
|
|
);
|
|
|
|
reassembled = process_reassembled_data(
|
|
payload, 0, pinfo,
|
|
"Reassembled LAPSat", fd_m, &lapsat_frag_items,
|
|
NULL, lapsat_tree
|
|
);
|
|
|
|
/* Reassembled into this packet ? */
|
|
if (fd_m && pinfo->num == fd_m->reassembled_in) {
|
|
/* Yes, so handoff to upper layers */
|
|
if (!dissector_try_uint(lapsat_sapi_dissector_table, sapi,
|
|
reassembled, pinfo, tree))
|
|
call_data_dissector(reassembled, pinfo, tree);
|
|
} else {
|
|
/* No, just add infos */
|
|
col_append_str(pinfo->cinfo, COL_INFO, " (Fragment)");
|
|
proto_tree_add_item(lapsat_tree, hf_lapsat_fragment_data, payload, 0, -1, ENC_NA);
|
|
}
|
|
|
|
/* Now reset fragmentation information in pinfo */
|
|
pinfo->fragmented = save_fragmented;
|
|
} else {
|
|
/*
|
|
* Whole frame
|
|
*/
|
|
if (!dissector_try_uint(lapsat_sapi_dissector_table, sapi, payload, pinfo, tree))
|
|
call_data_dissector(payload, pinfo, tree);
|
|
}
|
|
return tvb_captured_length(tvb);
|
|
}
|
|
|
|
void
|
|
proto_register_lapsat(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
/* Address field */
|
|
{ &hf_lapsat_addr,
|
|
{ "Address Field", "lapsat.address",
|
|
FT_UINT8, BASE_HEX, NULL, 0x00,
|
|
NULL, HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_sst,
|
|
{ "SST", "lapsat.address.sst",
|
|
FT_UINT8, BASE_DEC, VALS(lapsat_addr_sst_vals), LAPSAT_SST,
|
|
"SACCH status bit", HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_cr,
|
|
{ "C/R", "lapsat.address.cr",
|
|
FT_UINT8, BASE_DEC, NULL, LAPSAT_CR,
|
|
"Command/response bit", HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_sapi,
|
|
{ "SAPI", "lapsat.address.sapi",
|
|
FT_UINT8, BASE_DEC, VALS(lapsat_addr_sapi_vals), LAPSAT_SAPI_MSK,
|
|
"Service access point identifier", HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_si,
|
|
{ "SI", "lapsat.address.si",
|
|
FT_UINT8, BASE_DEC, VALS(lapsat_addr_si_vals), LAPSAT_SI,
|
|
"Segment Indicator", HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_lpd,
|
|
{ "LPD", "lapsat.address.lpd",
|
|
FT_UINT8, BASE_DEC, VALS(lapsat_addr_lpd_vals), LAPSAT_LPD_MSK,
|
|
"Link Protocol Discriminator", HFILL },
|
|
},
|
|
{ &hf_lapsat_addr_lfi,
|
|
{ "LFI", "lapsat.address.lfi",
|
|
FT_UINT8, BASE_DEC, VALS(lapsat_addr_lfi_vals), LAPSAT_LFI,
|
|
"Length Field Indicator", HFILL },
|
|
},
|
|
|
|
/* Control field */
|
|
{ &hf_lapsat_ctl,
|
|
{ "Control Field", "lapsat.control_field",
|
|
FT_UINT16, BASE_HEX, NULL, 0x00,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_ftype_i,
|
|
{ "Frame type", "lapsat.control.ftype",
|
|
FT_UINT16, BASE_DEC, VALS(lapsat_ctl_ftype_vals), LAPSAT_CTL_TYPE_I_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_ftype_s_u,
|
|
{ "Frame type", "lapsat.control.ftype",
|
|
FT_UINT16, BASE_DEC, VALS(lapsat_ctl_ftype_vals), LAPSAT_CTL_TYPE_S_U_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_s_ftype,
|
|
{ "Supervisory frame type", "lapsat.control.s_ftype",
|
|
FT_UINT16, BASE_DEC, VALS(lapsat_ctl_s_ftype_vals), LAPSAT_CTL_S_FTYPE_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_u_modifier_cmd,
|
|
{ "Command", "lapsat.control.u_modifier_cmd",
|
|
FT_UINT16, BASE_HEX, VALS(lapsat_ctl_u_modifier_vals_cmd),
|
|
LAPSAT_CTL_U_MODIFIER_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_u_modifier_resp,
|
|
{ "Response", "lapsat.control.u_modifier_resp",
|
|
FT_UINT16, BASE_HEX, VALS(lapsat_ctl_u_modifier_vals_resp),
|
|
LAPSAT_CTL_U_MODIFIER_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_n_r,
|
|
{ "N(R)", "lapsat.control.n_r",
|
|
FT_UINT16, BASE_DEC, NULL, LAPSAT_CTL_N_R_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_n_s,
|
|
{ "N(S)", "lapsat.control.n_s",
|
|
FT_UINT16, BASE_DEC, NULL, LAPSAT_CTL_N_S_MSK << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_p,
|
|
{ "Poll", "lapsat.control.p",
|
|
FT_UINT16, BASE_DEC, VALS(true_false_vals), LAPSAT_CTL_P_F << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_f,
|
|
{ "Final", "lapsat.control.f",
|
|
FT_UINT16, BASE_DEC, VALS(true_false_vals), LAPSAT_CTL_P_F << 4,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_ctl_mii,
|
|
{ "MII", "lapsat.control.mii",
|
|
FT_UINT16, BASE_DEC, VALS(true_false_vals), LAPSAT_CTL_MII << 4,
|
|
"Mobile Identity Indicator", HFILL }
|
|
},
|
|
|
|
/* Payload last nibble */
|
|
{ &hf_lapsat_payload_last_nibble,
|
|
{ "Payload last nibble", "lapsat.payload.last_nibble",
|
|
FT_UINT8, BASE_HEX, NULL, 0x0f,
|
|
NULL, HFILL }
|
|
},
|
|
|
|
/* Length field */
|
|
{ &hf_lapsat_len,
|
|
{ "Length Field", "lapsat.length",
|
|
FT_UINT8, BASE_DEC, NULL, 0x00,
|
|
NULL, HFILL },
|
|
},
|
|
|
|
/* Fragment reassembly */
|
|
{ &hf_lapsat_fragment_data,
|
|
{ "Fragment Data", "lapsat.fragment_data",
|
|
FT_BYTES, BASE_NONE, NULL, 0x00,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_fragments,
|
|
{ "Message fragments", "lapsat.fragments",
|
|
FT_NONE, BASE_NONE, NULL, 0x00,
|
|
"LAPSat Message fragments", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment,
|
|
{ "Message fragment", "lapsat.fragment",
|
|
FT_FRAMENUM, BASE_NONE, NULL, 0x00,
|
|
"LAPSat Message fragment", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_overlap,
|
|
{ "Message fragment overlap", "lapsat.fragment.overlap",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"LAPSat Message fragment overlaps with other fragment(s)", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_overlap_conflicts,
|
|
{ "Message fragment overlapping with conflicting data",
|
|
"lapsat.fragment.overlap.conflicts",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"LAPSat Message fragment overlaps with conflicting data", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_multiple_tails,
|
|
{ "Message has multiple tail fragments", "lapsat.fragment.multiple_tails",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"LAPSat Message fragment has multiple tail fragments", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_too_long_fragment,
|
|
{ "Message fragment too long", "lapsat.fragment.too_long_fragment",
|
|
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
|
|
"LAPSat Message fragment data goes beyond the packet end", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_error,
|
|
{ "Message defragmentation error", "lapsat.fragment.error",
|
|
FT_FRAMENUM, BASE_NONE, NULL, 0x00,
|
|
"LAPSat Message defragmentation error due to illegal fragments", HFILL }
|
|
},
|
|
{ &hf_lapsat_fragment_count,
|
|
{ "Message fragment count", "lapsat.fragment.count",
|
|
FT_UINT32, BASE_DEC, NULL, 0x00,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_lapsat_reassembled_in,
|
|
{ "Reassembled in", "lapsat.reassembled.in",
|
|
FT_FRAMENUM, BASE_NONE, NULL, 0x00,
|
|
"LAPSat Message has been reassembled in this packet.", HFILL }
|
|
},
|
|
{ &hf_lapsat_reassembled_length,
|
|
{ "Reassembled LAPSat length", "lapsat.reassembled.length",
|
|
FT_UINT32, BASE_DEC, NULL, 0x00,
|
|
"The total length of the reassembled payload", HFILL }
|
|
},
|
|
};
|
|
|
|
static gint *ett[] = {
|
|
&ett_lapsat,
|
|
&ett_lapsat_address,
|
|
&ett_lapsat_control,
|
|
&ett_lapsat_fragment,
|
|
&ett_lapsat_fragments,
|
|
};
|
|
|
|
proto_lapsat = proto_register_protocol("Link Access Procedure, Satellite channel (LAPSat)", "LAPSat", "lapsat");
|
|
|
|
proto_register_field_array (proto_lapsat, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
|
|
register_dissector("lapsat", dissect_lapsat, proto_lapsat);
|
|
|
|
lapsat_sapi_dissector_table = register_dissector_table("lapsat.sapi", "LAPSat SAPI", proto_lapsat, FT_UINT8, BASE_DEC, DISSECTOR_TABLE_NOT_ALLOW_DUPLICATE);
|
|
|
|
register_init_routine (lapsat_defragment_init);
|
|
register_cleanup_routine (lapsat_defragment_cleanup);
|
|
}
|
|
|
|
|
|
/*
|
|
* Editor modelines - http://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local variables:
|
|
* c-basic-offset: 8
|
|
* tab-width: 8
|
|
* indent-tabs-mode: t
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
|
|
* :indentSize=8:tabSize=8:noTabs=false:
|
|
*/
|