From e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 22:34:10 +0200 Subject: Adding upstream version 4.2.2. Signed-off-by: Daniel Baumann --- epan/dissectors/packet-sdlc.c | 212 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 212 insertions(+) create mode 100644 epan/dissectors/packet-sdlc.c (limited to 'epan/dissectors/packet-sdlc.c') diff --git a/epan/dissectors/packet-sdlc.c b/epan/dissectors/packet-sdlc.c new file mode 100644 index 00000000..78a571a6 --- /dev/null +++ b/epan/dissectors/packet-sdlc.c @@ -0,0 +1,212 @@ +/* packet-sdlc.c + * Routines for SDLC frame disassembly + * + * Wireshark - Network traffic analyzer + * By Gerald Combs + * Copyright 1998 + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "config.h" + +#include +#include +#include + +/* + * See: + * + * http://web.archive.org/web/20020206033700/http://www.wanresources.com/snacell.html + * + * http://web.archive.org/web/20150522015710/http://www.protocols.com/pbook/sna.htm + * + * Systems Network Architecture Formats, GA27-3136-20: + * https://publibz.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/D50A5007/CCONTENTS + */ +void proto_register_sdlc(void); +void proto_reg_handoff_sdlc(void); + +static dissector_handle_t sdlc_handle; + +static int proto_sdlc = -1; +static int hf_sdlc_address = -1; +static int hf_sdlc_control = -1; +static int hf_sdlc_n_r = -1; +static int hf_sdlc_n_s = -1; +static int hf_sdlc_p = -1; +static int hf_sdlc_f = -1; +static int hf_sdlc_s_ftype = -1; +static int hf_sdlc_u_modifier_cmd = -1; +static int hf_sdlc_u_modifier_resp = -1; +static int hf_sdlc_ftype_i = -1; +static int hf_sdlc_ftype_s_u = -1; + +static gint ett_sdlc = -1; +static gint ett_sdlc_control = -1; + +static dissector_handle_t sna_handle; + +static const xdlc_cf_items sdlc_cf_items = { + &hf_sdlc_n_r, + &hf_sdlc_n_s, + &hf_sdlc_p, + &hf_sdlc_f, + &hf_sdlc_s_ftype, + &hf_sdlc_u_modifier_cmd, + &hf_sdlc_u_modifier_resp, + &hf_sdlc_ftype_i, + &hf_sdlc_ftype_s_u +}; + +static int +dissect_sdlc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) +{ + proto_tree *sdlc_tree; + proto_item *sdlc_ti; + guint8 addr; + guint16 control; + int sdlc_header_len; + gboolean is_response; + tvbuff_t *next_tvb; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "SDLC"); + col_clear(pinfo->cinfo, COL_INFO); + + addr = tvb_get_guint8(tvb, 0); + sdlc_header_len = 1; /* address */ + + /* + * XXX - is there something in the SDLC header that indicates + * how to interpret "command vs. response" based on the + * direction? + */ + if (pinfo->p2p_dir == P2P_DIR_SENT) { + is_response = FALSE; + col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DCE"); + col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DTE"); + } + else { + /* XXX - what if the direction is unknown? */ + is_response = TRUE; + col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DTE"); + col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DCE"); + } + + sdlc_ti = proto_tree_add_item(tree, proto_sdlc, tvb, 0, -1, + ENC_NA); + sdlc_tree = proto_item_add_subtree(sdlc_ti, ett_sdlc); + + proto_tree_add_uint(sdlc_tree, hf_sdlc_address, tvb, 0, 1, + addr); + + /* + * XXX - SDLC has a mod-128 mode as well as a mod-7 mode. + * We can infer the mode from an SNRM/SRME frame, but if + * we don't see one of them, we may have to have a preference + * to control what to use. + */ + control = dissect_xdlc_control(tvb, 1, pinfo, sdlc_tree, hf_sdlc_control, + ett_sdlc_control, &sdlc_cf_items, NULL, NULL, NULL, + is_response, FALSE, FALSE); + sdlc_header_len += XDLC_CONTROL_LEN(control, FALSE); + + proto_item_set_len(sdlc_ti, sdlc_header_len); + + /* + * XXX - is there an FCS at the end, at least in Sniffer + * captures? (There doesn't appear to be.) + */ + next_tvb = tvb_new_subset_remaining(tvb, sdlc_header_len); + if (XDLC_IS_INFORMATION(control)) { + /* call the SNA dissector */ + call_dissector(sna_handle, next_tvb, pinfo, tree); + } else + call_data_dissector(next_tvb, pinfo, tree); + + return tvb_captured_length(tvb); +} + +void +proto_register_sdlc(void) +{ + static hf_register_info hf[] = { + { &hf_sdlc_address, + { "Address Field", "sdlc.address", FT_UINT8, BASE_HEX, + NULL, 0x0, "Address", HFILL }}, + + { &hf_sdlc_control, + { "Control Field", "sdlc.control", FT_UINT16, BASE_HEX, + NULL, 0x0, NULL, HFILL }}, + + { &hf_sdlc_n_r, + { "N(R)", "sdlc.control.n_r", FT_UINT8, BASE_DEC, + NULL, XDLC_N_R_MASK, NULL, HFILL }}, + + { &hf_sdlc_n_s, + { "N(S)", "sdlc.control.n_s", FT_UINT8, BASE_DEC, + NULL, XDLC_N_S_MASK, NULL, HFILL }}, + + { &hf_sdlc_p, + { "Poll", "sdlc.control.p", FT_BOOLEAN, 8, + TFS(&tfs_set_notset), XDLC_P_F, NULL, HFILL }}, + + { &hf_sdlc_f, + { "Final", "sdlc.control.f", FT_BOOLEAN, 8, + TFS(&tfs_set_notset), XDLC_P_F, NULL, HFILL }}, + + { &hf_sdlc_s_ftype, + { "Supervisory frame type", "sdlc.control.s_ftype", FT_UINT8, BASE_HEX, + VALS(stype_vals), XDLC_S_FTYPE_MASK, NULL, HFILL }}, + + { &hf_sdlc_u_modifier_cmd, + { "Command", "sdlc.control.u_modifier_cmd", FT_UINT8, BASE_HEX, + VALS(modifier_vals_cmd), XDLC_U_MODIFIER_MASK, NULL, HFILL }}, + + { &hf_sdlc_u_modifier_resp, + { "Response", "sdlc.control.u_modifier_resp", FT_UINT8, BASE_HEX, + VALS(modifier_vals_resp), XDLC_U_MODIFIER_MASK, NULL, HFILL }}, + + { &hf_sdlc_ftype_i, + { "Frame type", "sdlc.control.ftype", FT_UINT8, BASE_HEX, + VALS(ftype_vals), XDLC_I_MASK, NULL, HFILL }}, + + { &hf_sdlc_ftype_s_u, + { "Frame type", "sdlc.control.ftype", FT_UINT8, BASE_HEX, + VALS(ftype_vals), XDLC_S_U_MASK, NULL, HFILL }}, + }; + static gint *ett[] = { + &ett_sdlc, + &ett_sdlc_control, + }; + + proto_sdlc = proto_register_protocol("Synchronous Data Link Control (SDLC)", "SDLC", "sdlc"); + proto_register_field_array(proto_sdlc, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + sdlc_handle = register_dissector("sdlc", dissect_sdlc, proto_sdlc); +} + +void +proto_reg_handoff_sdlc(void) +{ + /* + * Get handle for the SNA dissector. + */ + sna_handle = find_dissector_add_dependency("sna", proto_sdlc); + + dissector_add_uint("wtap_encap", WTAP_ENCAP_SDLC, sdlc_handle); +} + +/* + * Editor modelines - https://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: + */ -- cgit v1.2.3