/* packet-flip.c * Routines for FLIP packet dissection * * Copyright 2009, Juha Siltanen * * $Id$ * * 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. */ /* * FLIP (Flow Layer Internal Protocol) is a proprietary protocol * developed by Nokia Siemens Networks. */ /* * Version information * * Version 0.0.1, November 23rd, 2009. * * Support for the basic and checksum headers. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include static int proto_flip = -1; /* BASIC */ static int hf_flip_basic_e = -1; static int hf_flip_basic_reserved = -1; static int hf_flip_basic_flowid = -1; static int hf_flip_basic_seqnum = -1; static int hf_flip_basic_len = -1; /* CHECKSUM */ static int hf_flip_chksum_etype = -1; static int hf_flip_chksum_spare = -1; static int hf_flip_chksum_e = -1; static int hf_flip_chksum_chksum = -1; #define FLIP_BASIC (0) #define FLIP_CHKSUM (1) #define FLIP_BASIC_HDR_LEN (8) #define FLIP_CHKSUM_HDR_LEN (4) #define FLIP_EXTENSION_HDR_MIN_LEN (4) static const value_string flip_short_header_names[]={ { FLIP_BASIC, "BASIC" }, { FLIP_CHKSUM, "CHKSUM"}, { 0, NULL} }; static const value_string flip_long_header_names[] = { { FLIP_BASIC, "Basic"}, { FLIP_CHKSUM, "Checksum"}, { 0, NULL } }; static const value_string flip_boolean[] = { {0, "No"}, {1, "Yes"}, {0, NULL} }; static const value_string flip_etype[] = { { FLIP_CHKSUM, "Checksum" }, { 0, NULL } }; static gint ett_flip = -1; static gint ett_flip_basic = -1; static gint ett_flip_chksum = -1; static gint ett_flip_payload = -1; /* Dissect the checksum extension header. */ static int dissect_flip_chksum_hdr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint16 computed_chksum, gboolean *ext_hdr_follows_ptr) { proto_item *item; proto_tree *chksum_hdr_tree; guint32 dw; guint8 chksum_hdr_etype; guint8 chksum_hdr_spare; guint8 chksum_hdr_ext; guint16 chksum_hdr_chksum; gint bytes_dissected; gint offset; item = NULL; chksum_hdr_tree = NULL; bytes_dissected = 0; offset = 0; dw = tvb_get_ntohl(tvb, offset); chksum_hdr_etype = (guint8) ((dw & 0xFF000000) >> 24); chksum_hdr_spare = (guint8) ((dw & 0x00FE0000) >> 17); chksum_hdr_ext = (guint8) ((dw & 0x00010000) >> 16); chksum_hdr_chksum = (guint16) (dw & 0x0000FFFF); /* The actually shouldn't be any headers after checksum. */ if (chksum_hdr_ext == 1) { *ext_hdr_follows_ptr = TRUE; } else { *ext_hdr_follows_ptr = FALSE; } if (tree) { item = proto_tree_add_text(tree, tvb, offset + 0, 4, "Checksum Header"); chksum_hdr_tree = proto_item_add_subtree(item, ett_flip_chksum); /* ETYPE: 8 bits */ proto_tree_add_uint_format_value(chksum_hdr_tree, hf_flip_chksum_etype, tvb, offset + 0, 1, dw, "%s", val_to_str(chksum_hdr_etype, flip_etype, "Unknown")); /* SPARE: 7 bits */ proto_tree_add_uint_format_value(chksum_hdr_tree, hf_flip_chksum_spare, tvb, offset + 1, 1, dw, "%d (0x%02x)", chksum_hdr_spare, chksum_hdr_spare); /* EXT HDR: 1 bit */ proto_tree_add_uint_format_value(chksum_hdr_tree, hf_flip_chksum_e, tvb, offset + 1, 1, dw, "%s", val_to_str(chksum_hdr_ext, flip_boolean, "Unknown")); /* CHKSUM: 16 bits. */ proto_tree_add_uint_format_value( chksum_hdr_tree, hf_flip_chksum_chksum, tvb, offset + 2, 2, chksum_hdr_chksum, "0x%04x [%s] (computed 0x%04x)", chksum_hdr_chksum, ((chksum_hdr_chksum == computed_chksum) ? "Correct" : "Incorrect"), computed_chksum); } /* Show faulty checksums. */ if (computed_chksum != chksum_hdr_chksum) { col_add_fstr(pinfo->cinfo, COL_INFO, "Checksum 0x%04x [%s] (computed 0x%04x)", chksum_hdr_chksum, ((chksum_hdr_chksum == computed_chksum) ? "Correct" : "Incorrect"), computed_chksum); } bytes_dissected += FLIP_CHKSUM_HDR_LEN; return bytes_dissected; } /* dissect_flip_chksum_hdr() */ /* Protocol dissection */ static int dissect_flip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { proto_item *item; proto_item *ti; proto_tree *flip_tree; proto_tree *basic_hdr_tree; proto_tree *payload_hdr_tree; tvbuff_t *flip_tvb; guint32 dw1; guint32 dw2; /* Basic header fields. */ guint8 basic_hdr_ext; guint8 basic_hdr_reserved; guint32 basic_hdr_flow_id; guint16 basic_hdr_seqnum; guint16 basic_hdr_len; gboolean ext_hdr; gint bytes_dissected; gint payload_len; gint frame_len; gint flip_len; gint offset; /* Error handling for basic header. */ gboolean is_faulty_frame; gboolean is_short_flip_len; gboolean is_invalid_flip_len; item = NULL; ti = NULL; flip_tree = NULL; basic_hdr_tree = NULL; payload_hdr_tree = NULL; flip_tvb = NULL; ext_hdr = FALSE; bytes_dissected = 0; payload_len = 0; frame_len = 0; flip_len = 0; offset = 0; is_faulty_frame = FALSE; is_short_flip_len = FALSE; is_invalid_flip_len = FALSE; /* Show this protocol as FLIP. */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "FLIP"); /* * The frame can be faulty in several ways: * - too short (even for the basic header) * - length inconsistent (header and frame info different) * - checksum doesn't check out * - extension header is indicated, but the frame is too short for it * - unknown extension header type */ /* Check that there's enough data at least for the basic header. */ frame_len = tvb_length(tvb); if (frame_len < FLIP_BASIC_HDR_LEN) { /* Not enough. This must be a malformed packet. */ goto DISSECT_FLIP_EXIT; } bytes_dissected += FLIP_BASIC_HDR_LEN; /* Process the first 32 bits of the basic header. */ dw1 = tvb_get_ntohl(tvb, offset + 0); basic_hdr_ext = ((dw1 & 0x80000000) >> 31); basic_hdr_reserved = ((dw1 & 0x70000000) >> 24); basic_hdr_flow_id = (dw1 & 0x0FFFFFFF); /* Process the second 32 bits of the basic header. */ dw2 = tvb_get_ntohl(tvb, offset + 4); basic_hdr_seqnum = (guint16) ((dw2 & 0xFFFF0000) >> 16); basic_hdr_len = (guint16) (dw2 & 0x0000FFFF); /* Does the basic header indicate that an extension is next? */ if (basic_hdr_ext == 1) { ext_hdr = TRUE; } flip_len = basic_hdr_len; /* * Check the length value. */ if ((flip_len < FLIP_BASIC_HDR_LEN) || (flip_len > frame_len)) { /* Faulty frame. Show the basic header anyway for debugging. */ is_faulty_frame = TRUE; } /* Fill in the info column. */ col_add_fstr(pinfo->cinfo, COL_INFO, "FlowID %s", val_to_str(basic_hdr_flow_id, NULL, "0x%08x")); flip_tvb = tvb_new_subset(tvb, 0, frame_len, frame_len); /* We are asked for details. */ if (tree) { ti = proto_tree_add_item(tree, proto_flip, flip_tvb, 0, flip_len, FALSE); flip_tree = proto_item_add_subtree(ti, ett_flip); /* basic header */ item = proto_tree_add_text(flip_tree, flip_tvb, 0, 8, "Basic Header"); basic_hdr_tree = proto_item_add_subtree(item, ett_flip_basic); /* Extension header follows? 1 bit. */ proto_tree_add_uint_format_value(basic_hdr_tree, hf_flip_basic_e, flip_tvb, offset + 0, 1, dw1, "%s", val_to_str(basic_hdr_ext, flip_boolean, "Unknown")); /* Reserved: 3 bits. */ proto_tree_add_uint_format_value(basic_hdr_tree, hf_flip_basic_reserved, flip_tvb, offset + 0, 1, dw1, "%d", basic_hdr_reserved); /* Flow ID: 28 bits. */ proto_tree_add_item(basic_hdr_tree, hf_flip_basic_flowid, flip_tvb, offset + 0, 4, FALSE); /* Sequence number: 16 bits. */ proto_tree_add_uint_format_value(basic_hdr_tree, hf_flip_basic_seqnum, flip_tvb, offset + 4, 2, dw2, "%d (0x%04x)", basic_hdr_seqnum, basic_hdr_seqnum); /* Packet length: 16 bits. */ proto_tree_add_uint_format_value(basic_hdr_tree, hf_flip_basic_len, flip_tvb, offset + 6, 2, dw2, "%d (0x%04x)", basic_hdr_len, basic_hdr_len); } offset += FLIP_BASIC_HDR_LEN; /* * Process faults found when parsing the basic header. */ if (is_faulty_frame == TRUE) { if (flip_len > frame_len) { col_add_fstr(pinfo->cinfo, COL_INFO, "Length mismatch: frame %d bytes, hdr %d bytes", frame_len, flip_len); } else if (flip_len < FLIP_BASIC_HDR_LEN) { col_add_fstr(pinfo->cinfo, COL_INFO, "Invalid length in basic header: %d bytes", flip_len); } goto DISSECT_FLIP_EXIT; } /* * Now we know that the basic header is sensible. */ payload_len = basic_hdr_len; payload_len -= FLIP_BASIC_HDR_LEN; /* * Dissect extension headers (if any). */ if ((ext_hdr == TRUE) && (payload_len < FLIP_EXTENSION_HDR_MIN_LEN)) { col_add_fstr(pinfo->cinfo, COL_INFO, "Extension header indicated, but not enough data"); goto DISSECT_FLIP_EXIT; } while ((ext_hdr == TRUE) && (payload_len >= FLIP_EXTENSION_HDR_MIN_LEN)) { /* Detect the next header type. */ guint8 ext_hdr_type; gint bytes_handled; guint16 computed_chksum; tvbuff_t *chksum_tvb; ext_hdr_type = tvb_get_guint8(flip_tvb, offset); switch (ext_hdr_type) { case FLIP_CHKSUM: /* Calculate checksum, let the chksum dissector verify it. */ { vec_t vec[2]; vec[0].ptr = tvb_get_ptr(flip_tvb, 0, bytes_dissected + 2); vec[0].len = bytes_dissected + 2; vec[1].ptr = tvb_get_ptr(flip_tvb, bytes_dissected + 4, flip_len - (bytes_dissected + 4)); vec[1].len = flip_len - (bytes_dissected + 4); computed_chksum = in_cksum(&vec[0], 2); /* Checksums handled in network order. */ computed_chksum = g_htons(computed_chksum); } chksum_tvb = tvb_new_subset(flip_tvb, offset, FLIP_CHKSUM_HDR_LEN, FLIP_CHKSUM_HDR_LEN); /* Note that flip_tree is NULL if no details are requested. */ bytes_handled = dissect_flip_chksum_hdr(chksum_tvb, pinfo, flip_tree, computed_chksum, &ext_hdr); bytes_dissected += bytes_handled; payload_len -= bytes_handled; offset += bytes_handled; break; default: /* Unknown header type. */ col_add_fstr(pinfo->cinfo, COL_INFO, "Invalid extension header type 0x%02x", ext_hdr_type); goto DISSECT_FLIP_EXIT; break; } } /* * Show payload (if any) as bytes. */ if (payload_len > 0) { if (tree) { tvbuff_t *payload_tvb; payload_tvb = tvb_new_subset(flip_tvb, offset, payload_len, payload_len); item = proto_tree_add_text(flip_tree, payload_tvb, 0, payload_len, "Payload (%d bytes)", payload_len); payload_hdr_tree = proto_item_add_subtree(item, ett_flip_payload); } bytes_dissected += payload_len; } DISSECT_FLIP_EXIT: return bytes_dissected; } /* dissect_flip() */ /* Protocol initialization */ void proto_register_flip(void) { static hf_register_info hf[] = { /* * Basic header. */ {&hf_flip_basic_e, {"Extension Header Follows", "flip.basic.e", FT_UINT32, BASE_DEC, VALS(flip_boolean), 0x80000000, NULL, HFILL} }, {&hf_flip_basic_reserved, {"Reserved", "flip.basic.reserved", FT_UINT32, BASE_DEC, NULL, 0x70000000, "Basic Header Reserved", HFILL} }, {&hf_flip_basic_flowid, {"FlowID", "flip.basic.flowid", FT_UINT32, BASE_HEX, NULL, 0x0FFFFFFF, "Basic Header Flow ID", HFILL} }, {&hf_flip_basic_seqnum, {"Seqnum", "flip.basic.seqnum", FT_UINT32, BASE_DEC, NULL, 0xFFFF0000, "Basic Header Sequence Number", HFILL} }, {&hf_flip_basic_len, {"Len", "flip.basic.len", FT_UINT32, BASE_DEC, NULL, 0x0000FFFF, "Basic Header Packet Length", HFILL} }, /* * Checksum header. */ {&hf_flip_chksum_etype, {"Extension Type", "flip.chksum.etype", FT_UINT32, BASE_DEC, VALS(flip_etype), 0xFF000000, "Checksum Header Extension Type", HFILL} }, {&hf_flip_chksum_spare, {"Spare", "flip.chksum.spare", FT_UINT32, BASE_DEC, NULL, 0x00FE0000, "Checksum Header Spare", HFILL} }, {&hf_flip_chksum_e, {"Extension Header Follows", "flip.chksum.e", FT_UINT32, BASE_DEC, VALS(flip_boolean), 0x00010000, NULL, HFILL} }, {&hf_flip_chksum_chksum, {"Checksum", "flip.chksum.chksum", FT_UINT32, BASE_HEX, NULL, 0x0000FFFF, NULL, HFILL} } }; static gint *ett[] = { &ett_flip, &ett_flip_basic, &ett_flip_chksum, &ett_flip_payload }; proto_flip = proto_register_protocol( "NSN FLIP", /* name */ "FLIP", /* short name */ "flip" /* abbrev */ ); proto_register_field_array(proto_flip, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); } /* proto_register_flip() */ /* Protocol handoff */ void proto_reg_handoff_flip(void) { dissector_handle_t flip_handle; flip_handle = new_create_dissector_handle(dissect_flip, proto_flip); dissector_add("ethertype", ETHERTYPE_FLIP, flip_handle); } /* proto_reg_handoff_flip() */ /* end of file packet-flip.c */