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Diffstat (limited to 'epan/dissectors/asn1/atn-cm/packet-atn-cm-template.c')
| -rw-r--r-- | epan/dissectors/asn1/atn-cm/packet-atn-cm-template.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/epan/dissectors/asn1/atn-cm/packet-atn-cm-template.c b/epan/dissectors/asn1/atn-cm/packet-atn-cm-template.c new file mode 100644 index 0000000000..5dc966e69c --- /dev/null +++ b/epan/dissectors/asn1/atn-cm/packet-atn-cm-template.c @@ -0,0 +1,244 @@ +/* packet-atn-cm.c + * By Mathias Guettler <guettler@web.de> + * Copyright 2013 + * + * Routines for ATN context management protocol packet disassembly. + * ATN context management allows an aircraft + * to log on to a ground facility. + + * details see: + * http://en.wikipedia.org/wiki/CPDLC + * http://members.optusnet.com.au/~cjr/introduction.htm + + * standards: + * http://legacy.icao.int/anb/panels/acp/repository.cfm + + * note: + * We are dealing with ATN/CPDLC aka ICAO Doc 9705 Ed2 here + * (CPDLC may also be transmitted via ACARS/AOA aka "FANS-1/A "). + + + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/exceptions.h> +#include <epan/conversation.h> +#include "packet-ber.h" +#include "packet-per.h" +#include "packet-atn-ulcs.h" + +#define ATN_CM_PROTO "ICAO Doc9705 CM" + +void proto_register_atn_cm(void); +void proto_reg_handoff_atn_cm(void); + +#include "packet-atn-cm-hf.c" + +#include "packet-atn-cm-ett.c" +static gint ett_atn_cm = -1; + +#include "packet-atn-cm-fn.c" +static int proto_atn_cm = -1; + +static int +dissect_atn_cm( + tvbuff_t *tvb, + packet_info *pinfo, + proto_tree *tree, + void *data _U_) +{ + int type; + proto_tree *sub_tree; + + sub_tree = proto_tree_add_subtree( + tree, tvb, 0, -1, ett_atn_cm, NULL, ATN_CM_PROTO); + + /* ti = proto_tree_add_item(tree, proto_atn_cm, tvb, 0, 0 , ENC_NA); */ + /* sub_tree = proto_item_add_subtree(ti, ett_atn_cm_pdu); */ + + /* determine whether it is uplink or downlink */ + type = check_heur_msg_type(pinfo); + + switch(type){ + case um: + dissect_CMGroundMessage_PDU( + tvb, + pinfo, + sub_tree, NULL); + break; + case dm: + dissect_CMAircraftMessage_PDU( + tvb, + pinfo, + sub_tree, NULL); + break; + default: + break; + } + return tvb_reported_length_remaining(tvb, 0); +} + +static gboolean +dissect_atn_cm_heur( + tvbuff_t *tvb, + packet_info *pinfo, + proto_tree *tree, + void *data _U_) +{ + atn_conversation_t *volatile atn_cv = NULL; + volatile gboolean is_atn_cm = FALSE; + int type; + + /* determine whether it is uplink or downlink */ + type = check_heur_msg_type(pinfo); + + /* heuristically decode message */ + switch(type){ + case um: + TRY { + dissect_CMGroundMessage_PDU( + tvb, + pinfo, + NULL, NULL); + /* no exception thrown: looks like it is a CM PDU */ + is_atn_cm = TRUE; } + CATCH_ALL { + is_atn_cm = FALSE; } + ENDTRY; + break; + case dm: + TRY { + dissect_CMAircraftMessage_PDU( + tvb, + pinfo, + NULL, NULL); + /* no exception thrown: looks like it is a CM PDU */ + is_atn_cm = TRUE;} + CATCH_ALL { + is_atn_cm = FALSE; } + ENDTRY; + break; + default: + break; + } + + if (is_atn_cm == TRUE) { + /* note: */ + /* all subsequent PDU's belonging to this conversation are considered CM */ + /* if the first CM PDU has been decoded successfully */ + /* (This is done in "atn-ulcs" by using "call_dissector_with_data()") */ + + /* DT: dstref present, srcref is always zero */ + if((pinfo->clnp_dstref) && + (!pinfo->clnp_srcref)){ + + atn_cv = find_atn_conversation( + &pinfo->dst, + pinfo->clnp_dstref, + &pinfo->src ); + } + /* CR: srcref present, dstref is always zero */ + if((!pinfo->clnp_dstref) && + (pinfo->clnp_srcref)){ + + atn_cv = find_atn_conversation( + &pinfo->src, + pinfo->clnp_srcref, + &pinfo->dst ); + + } + /* CC: srcref and dstref present */ + if((pinfo->clnp_dstref) && + (pinfo->clnp_srcref)){ + atn_cv = find_atn_conversation( + &pinfo->src, + pinfo->clnp_srcref, + &pinfo->dst ); + } + if(atn_cv){ + atn_cv->ae_qualifier = cma; + } + dissect_atn_cm( + tvb, + pinfo, + tree, + NULL); + } + + return is_atn_cm; +} + + +void proto_register_atn_cm (void) +{ + static hf_register_info hf_atn_cm[] = { + #include "packet-atn-cm-hfarr.c" + }; + static gint *ett[] = { + #include "packet-atn-cm-ettarr.c" + &ett_atn_cm + }; + + /* register CM application */ + proto_atn_cm = proto_register_protocol( + ATN_CM_PROTO , + "ATN-CM", + "atn-cm"); + + proto_register_field_array( + proto_atn_cm, + hf_atn_cm, + array_length(hf_atn_cm)); + + proto_register_subtree_array( + ett, + array_length(ett)); + + register_dissector( + "atn-cm", + dissect_atn_cm, + proto_atn_cm); +} + +void proto_reg_handoff_atn_cm(void) +{ + /* add session dissector to subdissector list*/ + heur_dissector_add( + "atn-ulcs", + dissect_atn_cm_heur, + "ATN-CM over ATN-ULCS", + "atn-cm-ulcs", + proto_atn_cm, HEURISTIC_ENABLE); +} + +/* + * Editor modelines - http://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ |