/* packet-brdwlk.c * Routines for decoding MDS Port Analyzer Adapter (FC in Eth) Header * Copyright 2001, Dinesh G Dutt * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include #include "packet-fc.h" #define BRDWLK_MAX_PACKET_CNT 0xFFFF #define BRDWLK_TRUNCATED_BIT 0x8 #define BRDWLK_HAS_PLEN 0x1 #define FCM_DELIM_SOFC1 0x01 #define FCM_DELIM_SOFI1 0x02 #define FCM_DELIM_SOFI2 0x04 #define FCM_DELIM_SOFI3 0x06 #define FCM_DELIM_SOFN1 0x03 #define FCM_DELIM_SOFN2 0x05 #define FCM_DELIM_SOFN3 0x07 #define FCM_DELIM_SOFF 0x08 #define FCM_DELIM_SOFC4 0x09 #define FCM_DELIM_SOFI4 0x0A #define FCM_DELIM_SOFN4 0x0B #define FCM_DELIM_EOFT 0x01 #define FCM_DELIM_EOFDT 0x02 #define FCM_DELIM_EOFN 0x03 #define FCM_DELIM_EOFA 0x04 #define FCM_DELIM_EOFNI 0x07 #define FCM_DELIM_EOFDTI 0x06 #define FCM_DELIM_EOFRT 0x0A #define FCM_DELIM_EOFRTI 0x0E #define FCM_DELIM_NOEOF 0xF0 #define FCM_DELIM_EOFJUMBO 0xF1 void proto_register_brdwlk(void); void proto_reg_handoff_brdwlk(void); static const value_string brdwlk_sof_vals[] = { {FCM_DELIM_SOFI1, "SOFi1"}, {FCM_DELIM_SOFI2, "SOFi2"}, {FCM_DELIM_SOFI3, "SOFi3"}, {FCM_DELIM_SOFN1, "SOFn1"}, {FCM_DELIM_SOFN2, "SOFn2"}, {FCM_DELIM_SOFN3, "SOFn3"}, {FCM_DELIM_SOFF, "SOFf"}, {0, NULL}, }; static const value_string brdwlk_eof_vals[] = { {FCM_DELIM_EOFDT, "EOFdt"}, {FCM_DELIM_EOFA, "EOFa"}, {FCM_DELIM_EOFN, "EOFn"}, {FCM_DELIM_EOFT, "EOFt"}, {0, NULL}, }; static int hf_brdwlk_sof; static int hf_brdwlk_eof; static int hf_brdwlk_error; static int hf_brdwlk_vsan; static int hf_brdwlk_pktcnt; static int hf_brdwlk_drop; static int hf_brdwlk_plen; static int hf_brdwlk_error_plp; static int hf_brdwlk_error_ef; static int hf_brdwlk_error_nd; static int hf_brdwlk_error_tr; static int hf_brdwlk_error_badcrc; static int hf_brdwlk_error_ff; static int hf_brdwlk_error_jumbo; static int hf_brdwlk_error_ctrl; /* Initialize the subtree pointers */ static int ett_brdwlk; static int ett_brdwlk_error; static int proto_brdwlk; static uint16_t packet_count; static bool first_pkt = true; /* start of capture */ static dissector_handle_t fc_dissector_handle; static dissector_handle_t brdwlk_handle; static const true_false_string tfs_error_plp = { "Packet Length is PRESENT", "Packet length is NOT present" }; static const true_false_string tfs_error_ef = { "This is an Empty Frame", "Frame is NOT empty" }; static const true_false_string tfs_error_nd = { "This Frame has NO Data", "This frame carries data" }; static const true_false_string tfs_error_tr = { "This frame is TRUNCATED", "This frame is NOT truncated" }; static const true_false_string tfs_error_crc = { "This Frame has a BAD FC CRC", "This frame has a valid crc" }; static const true_false_string tfs_error_ff = { "Fifo is Full", "Fifo is NOT full" }; static const true_false_string tfs_error_jumbo = { "This is a JUMBO FC Frame", "This is a NORMAL FC Frame" }; static const true_false_string tfs_error_ctrl = { "Ctrl Characters inside the frame", "No ctrl chars inside the frame" }; static void dissect_brdwlk_err(proto_tree *parent_tree, tvbuff_t *tvb, int offset) { static int * const flags[] = { &hf_brdwlk_error_plp, &hf_brdwlk_error_ef, &hf_brdwlk_error_nd, &hf_brdwlk_error_tr, &hf_brdwlk_error_badcrc, &hf_brdwlk_error_ff, &hf_brdwlk_error_jumbo, &hf_brdwlk_error_ctrl, NULL }; proto_tree_add_bitmask_with_flags(parent_tree, tvb, offset, hf_brdwlk_error, ett_brdwlk_error, flags, ENC_NA, BMT_NO_FALSE|BMT_NO_TFS); } /* Code to actually dissect the packets */ static int dissect_brdwlk(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { /* Set up structures needed to add the protocol subtree and manage it */ proto_item *ti, *hidden_item; proto_tree *brdwlk_tree; tvbuff_t *next_tvb; uint8_t error, eof, sof; int hdrlen = 2, offset = 0; int len, reported_len, plen; uint16_t pkt_cnt; bool dropped_packets; fc_data_t fc_data; /* Make entries in Protocol column and Info column on summary display */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "Boardwalk"); col_clear(pinfo->cinfo, COL_INFO); sof = (tvb_get_uint8(tvb, offset) & 0xF0) >> 4; fc_data.sof_eof = 0; if ((sof == FCM_DELIM_SOFI3) || (sof == FCM_DELIM_SOFI2) || (sof == FCM_DELIM_SOFI1) || (sof == FCM_DELIM_SOFI4)) { fc_data.sof_eof = FC_DATA_SOF_FIRST_FRAME; } else if (sof == FCM_DELIM_SOFF) { fc_data.sof_eof = FC_DATA_SOF_SOFF; } ti = proto_tree_add_protocol_format(tree, proto_brdwlk, tvb, 0, hdrlen, "Boardwalk"); brdwlk_tree = proto_item_add_subtree(ti, ett_brdwlk); proto_tree_add_item(brdwlk_tree, hf_brdwlk_sof, tvb, offset, 1, ENC_BIG_ENDIAN); proto_tree_add_item(brdwlk_tree, hf_brdwlk_vsan, tvb, offset, 2, ENC_BIG_ENDIAN); /* Locate EOF which is the last 4 bytes of the frame */ len = tvb_captured_length_remaining(tvb, hdrlen); reported_len = tvb_reported_length_remaining(tvb, hdrlen); if (reported_len < 4) { /* * This packet is claimed not to even have enough data for * a 4-byte EOF. * Don't try to process the EOF. */ ; } else if (len < reported_len) { /* * This packet is claimed to have enough data for a 4-byte EOF, * but we didn't capture all of the packet. * Slice off the 4-byte EOF from the reported length, and trim * the captured length so it's no more than the reported length; * that will slice off what of the EOF, if any, is in the * captured length. */ reported_len -= 4; if (len > reported_len) len = reported_len; } else { /* * We have the entire packet, and it includes a 4-byte EOF. * Slice it off, and put it into the tree if we're building * a tree. */ len -= 4; reported_len -= 4; offset = tvb_reported_length(tvb) - 4; pkt_cnt = tvb_get_ntohs(tvb, offset); if (tree) { proto_tree_add_uint(brdwlk_tree, hf_brdwlk_pktcnt, tvb, offset, 2, pkt_cnt); } dropped_packets = false; if (pinfo->fd->visited) { /* * This isn't the first pass, so we can't use the global * "packet_count" variable to determine whether there were * any dropped frames or not. * We therefore attach a non-null pointer as frame data to * any frame preceded by dropped packets. */ if (p_get_proto_data(wmem_file_scope(), pinfo, proto_brdwlk, 0) != NULL) dropped_packets = true; } else { /* * This is the first pass, so we have to use the global * "packet_count" variable to determine whether there were * any dropped frames or not. * * XXX - can there be more than one stream of packets, so that * we can't just use a global variable? */ if (pkt_cnt != packet_count + 1) { if (!first_pkt && (pkt_cnt != 0 || (packet_count != BRDWLK_MAX_PACKET_CNT))) { dropped_packets = true; /* * Mark this frame as having been preceded by dropped * packets. (The data we use as the frame data doesn't * matter - it just matters that it's non-null.) */ p_add_proto_data(wmem_file_scope(), pinfo, proto_brdwlk, 0, &packet_count); } } } hidden_item = proto_tree_add_boolean(brdwlk_tree, hf_brdwlk_drop, tvb, offset, 0, dropped_packets); proto_item_set_hidden(hidden_item); packet_count = pkt_cnt; error=tvb_get_uint8(tvb, offset+2); dissect_brdwlk_err(brdwlk_tree, tvb, offset+2); eof = tvb_get_uint8(tvb, offset+3); if (eof != FCM_DELIM_EOFN) { fc_data.sof_eof |= FC_DATA_EOF_LAST_FRAME; } else if (eof != FCM_DELIM_EOFT) { fc_data.sof_eof |= FC_DATA_EOF_INVALID; } proto_tree_add_item(brdwlk_tree, hf_brdwlk_eof, tvb, offset+3, 1, ENC_BIG_ENDIAN); if ((error & BRDWLK_HAS_PLEN) && tree) { /* In newer Boardwalks, if this bit is set, the actual frame length * is also provided. This length is the size between SOF & EOF * including FC CRC. */ plen = tvb_get_ntohl(tvb, offset-4); plen *= 4; proto_tree_add_uint(brdwlk_tree, hf_brdwlk_plen, tvb, offset-4, 4, plen); #if 0 /* XXX - this would throw an exception if it would increase * the reported length. */ if (error & BRDWLK_TRUNCATED_BIT) { tvb_set_reported_length(tvb, plen); } #endif } } fc_data.ethertype = ETHERTYPE_BRDWALK; next_tvb = tvb_new_subset_length_caplen(tvb, 2, len, reported_len); call_dissector_with_data(fc_dissector_handle, next_tvb, pinfo, tree, &fc_data); return tvb_captured_length(tvb); } static void brdwlk_init(void) { packet_count = 0; first_pkt = true; } /* Register the protocol with Wireshark */ /* this format is require because a script is used to build the C function that calls all the protocol registration. */ void proto_register_brdwlk(void) { /* Setup list of header fields See Section 1.6.1 for details*/ static hf_register_info hf[] = { { &hf_brdwlk_sof, {"SOF", "brdwlk.sof", FT_UINT8, BASE_HEX, VALS(brdwlk_sof_vals), 0xF0, NULL, HFILL}}, { &hf_brdwlk_eof, {"EOF", "brdwlk.eof", FT_UINT8, BASE_HEX, VALS(brdwlk_eof_vals), 0x0F, NULL, HFILL}}, { &hf_brdwlk_error, {"Error", "brdwlk.error", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL}}, { &hf_brdwlk_pktcnt, {"Packet Count", "brdwlk.pktcnt", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL}}, { &hf_brdwlk_drop, {"Packet Dropped", "brdwlk.drop", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL}}, { &hf_brdwlk_vsan, {"VSAN", "brdwlk.vsan", FT_UINT16, BASE_DEC, NULL, 0x0FFF, NULL, HFILL}}, { &hf_brdwlk_plen, {"Original Packet Length", "brdwlk.plen", FT_UINT32, BASE_DEC, NULL, 0x0, NULL, HFILL}}, { &hf_brdwlk_error_plp, {"Packet Length Present", "brdwlk.error.plp", FT_BOOLEAN, 8, TFS(&tfs_error_plp), 0x01, NULL, HFILL}}, { &hf_brdwlk_error_ef, {"Empty Frame", "brdwlk.error.ef", FT_BOOLEAN, 8, TFS(&tfs_error_ef), 0x02, NULL, HFILL}}, { &hf_brdwlk_error_nd, {"No Data", "brdwlk.error.nd", FT_BOOLEAN, 8, TFS(&tfs_error_nd), 0x04, NULL, HFILL}}, { &hf_brdwlk_error_tr, {"Truncated", "brdwlk.error.tr", FT_BOOLEAN, 8, TFS(&tfs_error_tr), 0x08, NULL, HFILL}}, { &hf_brdwlk_error_badcrc, {"CRC", "brdwlk.error.crc", FT_BOOLEAN, 8, TFS(&tfs_error_crc), 0x10, NULL, HFILL}}, { &hf_brdwlk_error_ff, {"Fifo Full", "brdwlk.error.ff", FT_BOOLEAN, 8, TFS(&tfs_error_ff), 0x20, NULL, HFILL}}, { &hf_brdwlk_error_jumbo, {"Jumbo FC Frame", "brdwlk.error.jumbo", FT_BOOLEAN, 8, TFS(&tfs_error_jumbo), 0x40, NULL, HFILL}}, { &hf_brdwlk_error_ctrl, {"Ctrl Char Inside Frame", "brdwlk.error.ctrl", FT_BOOLEAN, 8, TFS(&tfs_error_ctrl), 0x80, NULL, HFILL}}, }; /* Setup protocol subtree array */ static int *ett[] = { &ett_brdwlk, &ett_brdwlk_error, }; /* Register the protocol name and description */ proto_brdwlk = proto_register_protocol("Boardwalk", "Boardwalk", "brdwlk"); /* Required function calls to register the header fields and subtrees used */ proto_register_field_array(proto_brdwlk, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_init_routine(&brdwlk_init); /* Register the dissector */ brdwlk_handle = register_dissector("brdwlk", dissect_brdwlk, proto_brdwlk); } void proto_reg_handoff_brdwlk(void) { dissector_add_uint("ethertype", ETHERTYPE_BRDWALK, brdwlk_handle); dissector_add_uint("ethertype", 0xABCD, brdwlk_handle); fc_dissector_handle = find_dissector_add_dependency("fc", proto_brdwlk); } /* * Editor modelines - https://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: */