/* packet-pw-hdlc.c * Routines for HDLC PW dissection as per RFC4618. * Copyright 2009, Dmitry Trebich, Artem Tamazov * * $Id$ * * Wireshark - Network traffic analyzer * By Gerald Combs * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * History: * --------------------------------- * 02.03.2009 Initial implementation, supports: * - HDLC mode (rfc4618 5.1), no CW, payload is PPP (PPP in HDLC-like Framing (rfc1662)). * - FR port mode (rfc4618 5.2), no CW. * * [informative: Not supported yet: * - All kinds of HDLC PW with CW. * - PPP mode (rfc4618 5.3). * - For HDLC mode, decoding payloads other than PPP.] */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include #include "packet-mpls.h" static dissector_handle_t ppp_handle; static dissector_handle_t fr_handle; static gint proto_pw_hdlc_nocw_fr = -1; static gint proto_pw_hdlc_nocw_hdlc_ppp = -1; static gint ett_pw_hdlc = -1; static int hf_pw_hdlc = -1; static int hf_pw_hdlc_address_field = -1; static int hf_pw_hdlc_address = -1; static int hf_pw_hdlc_cr_bit = -1; static int hf_pw_hdlc_control_field = -1; static int hf_pw_hdlc_pf_bit = -1; static void dissect_pw_hdlc_nocw_fr( tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree ) { call_dissector( fr_handle, tvb, pinfo, tree ); } static void dissect_pw_hdlc_nocw_hdlc_ppp( tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree ) { if (tvb_reported_length_remaining(tvb, 0) < 2) { if (tree) { proto_tree_add_text(tree, tvb, 0, -1, "Error processing message"); } return; } if (tree) { proto_tree *tr; proto_item *item; proto_item *item_address; proto_item *item_control; guint8 address; guint8 control; address = tvb_get_guint8(tvb, 0); control = tvb_get_guint8(tvb, 1); item = proto_tree_add_item( tree, proto_pw_hdlc_nocw_hdlc_ppp, tvb, 0, 2, FALSE ); tr = proto_item_add_subtree( item, ett_pw_hdlc ); item_address = proto_tree_add_uint( tr, hf_pw_hdlc_address_field, tvb, 0, 1, address ); item_control = proto_tree_add_uint_format( tr, hf_pw_hdlc_control_field, tvb, 1, 1, control, "Control field: 0x%x", control ); tr = proto_item_add_subtree( item_address, ett_pw_hdlc ); if ( 0x3F == (( address & 0xFC ) >> 2 )) proto_tree_add_uint_format( tr, hf_pw_hdlc_address, tvb, 0, 1, 0xFC, "Address: 0x%x (All stations)", 0x3F ); else proto_tree_add_uint( tr, hf_pw_hdlc_address, tvb, 0, 1, ( address & 0xFC ) >> 2 ); proto_tree_add_uint( tr, hf_pw_hdlc_cr_bit, tvb, 0, 1, ( address & 2 ) >> 1 ); tr = proto_item_add_subtree( item_control, ett_pw_hdlc ); if ( control & 1 ) { if ( control & 2 ) { guint8 modifier2; guint8 modifier3; proto_tree_add_text( tr, tvb, 1, 1, "U frame" ); proto_tree_add_uint( tr, hf_pw_hdlc_pf_bit, tvb, 1, 1, ( control & 0x10 ) >> 4 ); modifier2 = (( control & 0xC ) >> 2 ); modifier3 = (( control & 0xE0 ) >> 5 ); /**/ if ( modifier2 == 0 && modifier3 == 0 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: UI - Unnumbered information" ); else if ( modifier2 == 0 && modifier3 == 1 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: UP - Unnumbered poll" ); else if ( modifier2 == 0 && modifier3 == 2 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: DISC/RD - Disconnect/Request disconnect" ); else if ( modifier2 == 0 && modifier3 == 3 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: UA - Unnumbered acknowledgment" ); else if ( modifier2 == 0 && modifier3 == 4 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SNRM - Set normal response mode" ); else if ( modifier2 == 0 && modifier3 == 7 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: TEST - Test" ); else if ( modifier2 == 1 && modifier3 == 0 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SIM/RIM" " - Set initialization mode/Request initialization mode" ); else if ( modifier2 == 1 && modifier3 == 4 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: FRMR - Frame reject" ); else if ( modifier2 == 3 && modifier3 == 0 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SARM/DM" " - Set asynchronous response mode/Disconnect mode" ); else if ( modifier2 == 3 && modifier3 == 1 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SABM - Set asynchronous balanced mode" ); else if ( modifier2 == 3 && modifier3 == 2 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SARME - Set asynchronous response extended mode" ); else if ( modifier2 == 3 && modifier3 == 3 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SABME - Set asynchronous balanced extended mode" ); else if ( modifier2 == 3 && modifier3 == 4 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: RSET - Reset" ); else if ( modifier2 == 3 && modifier3 == 5 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: XID - Exchange identification" ); else if ( modifier2 == 3 && modifier3 == 6 ) proto_tree_add_text( tr, tvb, 1, 1, "Modifier: SNRME - Set normal response extended mode" ); } else { proto_tree_add_text( tr, tvb, 1, 1, "S frame" ); } } else { proto_tree_add_text( tr, tvb, 1, 1, "I frame" ); } } call_dissector( ppp_handle, tvb_new_subset_remaining(tvb, 2), pinfo, tree ); } void proto_register_pw_hdlc(void) { static hf_register_info hf[] = { { &hf_pw_hdlc, { "PW HDLC", "pw_hdlc", FT_NONE, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_pw_hdlc_address_field, { "Address field", "pw_hdlc.address_field", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_pw_hdlc_address, { "Address", "pw_hdlc.address", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_pw_hdlc_cr_bit, { "C/R bit", "pw_hdlc.cr_bit", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_pw_hdlc_control_field, { "Control field", "pw_hdlc.control_field", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_pw_hdlc_pf_bit, { "Poll/Final bit", "pw_hdlc.pf_bit", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL } } }; static gint *ett[] = { &ett_pw_hdlc }; proto_pw_hdlc_nocw_fr = proto_register_protocol("HDLC PW, FR port mode (no CW)", /*not displayed*/ "HDLC PW, FR port mode (no CW)", "pw_hdlc_nocw_fr" ); proto_pw_hdlc_nocw_hdlc_ppp = proto_register_protocol("HDLC-like framing for PPP", "HDLC PW with PPP payload (no CW)", "pw_hdlc_nocw_hdlc_ppp" ); proto_register_field_array(proto_pw_hdlc_nocw_fr, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("pw_hdlc_nocw_fr", dissect_pw_hdlc_nocw_fr, proto_pw_hdlc_nocw_fr ); register_dissector("pw_hdlc_nocw_hdlc_ppp", dissect_pw_hdlc_nocw_hdlc_ppp, proto_pw_hdlc_nocw_hdlc_ppp ); } void proto_reg_handoff_pw_hdlc(void) { dissector_handle_t handle; handle = find_dissector("pw_hdlc_nocw_fr"); dissector_add( "mpls.label", LABEL_INVALID, handle ); handle = find_dissector("pw_hdlc_nocw_hdlc_ppp"); dissector_add( "mpls.label", LABEL_INVALID, handle ); ppp_handle = find_dissector( "ppp" ); fr_handle = find_dissector( "fr" ); }