epan/dissectors/packet-idp.c

   1 /* packet-idp.c
   2  * Routines for XNS IDP
   3  * Based on the Netware IPX dissector by Gilbert Ramirez <gram@alumni.rice.edu>
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #include "config.h"
  13
  14 #include <epan/packet.h>
  15 #include "packet-idp.h"
  16 #include <epan/etypes.h>
  17 #include <epan/unit_strings.h>
  18
  19 void proto_register_idp(void);
  20 void proto_reg_handoff_idp(void);
  21
  22 static dissector_handle_t idp_handle;
  23
  24 static int proto_idp;
  25 static int hf_idp_checksum;
  26 static int hf_idp_len;
  27 /* static int hf_idp_src; */
  28 /* static int hf_idp_dst; */
  29 static int hf_idp_hops;
  30 static int hf_idp_packet_type;
  31 static int hf_idp_dnet;
  32 static int hf_idp_dnode;
  33 static int hf_idp_dsocket;
  34 static int hf_idp_snet;
  35 static int hf_idp_snode;
  36 static int hf_idp_ssocket;
  37
  38 static int ett_idp;
  39
  40 static dissector_table_t idp_type_dissector_table;
  41
  42 /*
  43  * See
  44  *
  45  *      "Internet Transport Protocols", XSIS 028112, December 1981
  46  *
  47  * if you can find it; this is based on the headers in the BSD XNS
  48  * implementation.
  49  */
  50
  51 #define IDP_HEADER_LEN  30              /* It's *always* 30 bytes */
  52
  53 static const value_string idp_packet_type_vals[] = {
  54         { IDP_PACKET_TYPE_RIP,          "RIP" },
  55         { IDP_PACKET_TYPE_ECHO,         "Echo" },
  56         { IDP_PACKET_TYPE_ERROR,        "Error" },
  57         { IDP_PACKET_TYPE_PEP,          "PEP" },
  58         { IDP_PACKET_TYPE_SPP,          "SPP" },
  59         { 0,                            NULL }
  60 };
  61
  62 static const value_string idp_socket_vals[] = {
  63         { IDP_SOCKET_SMB,               "SMB" },
  64         { 0,                            NULL }
  65 };
  66
  67 static int
  68 dissect_idp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  69 {
  70         proto_tree      *idp_tree;
  71         proto_item      *ti;
  72         uint16_t                length;
  73         uint8_t         type;
  74         tvbuff_t        *next_tvb;
  75
  76         col_set_str(pinfo->cinfo, COL_PROTOCOL, "IDP");
  77         col_clear(pinfo->cinfo, COL_INFO);
  78
  79         ti = proto_tree_add_item(tree, proto_idp, tvb, 0, IDP_HEADER_LEN, ENC_NA);
  80         idp_tree = proto_item_add_subtree(ti, ett_idp);
  81
  82         proto_tree_add_checksum(idp_tree, tvb, 0, hf_idp_checksum, -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
  83         length = tvb_get_ntohs(tvb, 2);
  84         proto_tree_add_uint(idp_tree, hf_idp_len, tvb, 2, 2, length);
  85         /* Adjust the tvbuff length to include only the IDP datagram. */
  86         set_actual_length(tvb, length);
  87         proto_tree_add_item(idp_tree, hf_idp_hops, tvb, 4, 1, ENC_BIG_ENDIAN);
  88         type = tvb_get_uint8(tvb, 5);
  89         proto_tree_add_uint(idp_tree, hf_idp_packet_type, tvb, 5, 1, type);
  90
  91         pinfo->ptype = PT_IDP;
  92
  93         /* Destination */
  94         proto_tree_add_item(idp_tree, hf_idp_dnet, tvb, 6, 4, ENC_BIG_ENDIAN);
  95         proto_tree_add_item(idp_tree, hf_idp_dnode, tvb, 10, 6, ENC_NA);
  96         pinfo->destport = tvb_get_ntohs(tvb, 16);
  97         proto_tree_add_uint(idp_tree, hf_idp_dsocket, tvb, 16, 2,
  98             pinfo->destport);
  99
 100         /* Source */
 101         proto_tree_add_item(idp_tree, hf_idp_snet, tvb, 18, 4, ENC_BIG_ENDIAN);
 102         proto_tree_add_item(idp_tree, hf_idp_snode, tvb, 22, 6, ENC_NA);
 103         pinfo->srcport = tvb_get_ntohs(tvb, 28);
 104         proto_tree_add_uint(idp_tree, hf_idp_ssocket, tvb, 28, 2,
 105             pinfo->srcport);
 106
 107         /* Make the next tvbuff */
 108         next_tvb = tvb_new_subset_remaining(tvb, IDP_HEADER_LEN);
 109
 110         /*
 111          * Hand off to the dissector for the packet type.
 112          */
 113         if (!dissector_try_uint(idp_type_dissector_table, type, next_tvb,
 114                 pinfo, tree))
 115         {
 116                 call_data_dissector(next_tvb, pinfo, tree);
 117         }
 118         return tvb_captured_length(tvb);
 119 }
 120
 121 void
 122 proto_register_idp(void)
 123 {
 124         static hf_register_info hf_idp[] = {
 125                 { &hf_idp_checksum,
 126                     { "Checksum",       "idp.checksum", FT_UINT16, BASE_HEX,
 127                         NULL, 0x0, NULL, HFILL }},
 128
 129 #if 0
 130                 { &hf_idp_src,
 131                     { "Source Address", "idp.src", FT_STRING, BASE_NONE,
 132                         NULL, 0x0, NULL, HFILL }},
 133 #endif
 134
 135 #if 0
 136                 { &hf_idp_dst,
 137                     { "Destination Address",    "idp.dst", FT_STRING, BASE_NONE,
 138                         NULL, 0x0,  NULL, HFILL }},
 139 #endif
 140
 141                 { &hf_idp_len,
 142                     { "Length",         "idp.len", FT_UINT16, BASE_DEC|BASE_UNIT_STRING,
 143                         UNS(&units_byte_bytes), 0x0, NULL, HFILL }},
 144
 145                 /* XXX - does this have separate hop count and time subfields? */
 146                 { &hf_idp_hops,
 147                     { "Transport Control (Hops)", "idp.hops", FT_UINT8, BASE_DEC,
 148                         NULL, 0x0, NULL, HFILL }},
 149
 150                 { &hf_idp_packet_type,
 151                     { "Packet Type",    "idp.packet_type", FT_UINT8, BASE_DEC,
 152                         VALS(idp_packet_type_vals), 0x0, NULL, HFILL }},
 153
 154                 { &hf_idp_dnet,
 155                     { "Destination Network","idp.dst.net", FT_UINT32, BASE_HEX,
 156                         NULL, 0x0, NULL, HFILL }},
 157
 158                 { &hf_idp_dnode,
 159                     { "Destination Node",       "idp.dst.node", FT_ETHER, BASE_NONE,
 160                         NULL, 0x0, NULL, HFILL }},
 161
 162                 { &hf_idp_dsocket,
 163                     { "Destination Socket",     "idp.dst.socket", FT_UINT16, BASE_HEX,
 164                         VALS(idp_socket_vals), 0x0, NULL, HFILL }},
 165
 166                 { &hf_idp_snet,
 167                     { "Source Network","idp.src.net", FT_UINT32, BASE_HEX,
 168                         NULL, 0x0, NULL, HFILL }},
 169
 170                 { &hf_idp_snode,
 171                     { "Source Node",    "idp.src.node", FT_ETHER, BASE_NONE,
 172                         NULL, 0x0, NULL, HFILL }},
 173
 174                 { &hf_idp_ssocket,
 175                     { "Source Socket",  "idp.src.socket", FT_UINT16, BASE_HEX,
 176                         VALS(idp_socket_vals), 0x0, NULL, HFILL }},
 177         };
 178
 179         static int *ett[] = {
 180                 &ett_idp,
 181         };
 182
 183         proto_idp = proto_register_protocol("Internetwork Datagram Protocol",
 184             "IDP", "idp");
 185         proto_register_field_array(proto_idp, hf_idp, array_length(hf_idp));
 186         proto_register_subtree_array(ett, array_length(ett));
 187
 188         idp_type_dissector_table = register_dissector_table("idp.packet_type",
 189             "IDP packet type", proto_idp, FT_UINT8, BASE_DEC);
 190
 191         idp_handle = register_dissector("idp", dissect_idp, proto_idp);
 192 }
 193
 194 void
 195 proto_reg_handoff_idp(void)
 196 {
 197         dissector_add_uint("ethertype", ETHERTYPE_XNS_IDP, idp_handle);
 198         dissector_add_uint("chdlc.protocol", ETHERTYPE_XNS_IDP, idp_handle);
 199 }
 200
 201 /*
 202  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 203  *
 204  * Local variables:
 205  * c-basic-offset: 8
 206  * tab-width: 8
 207  * indent-tabs-mode: t
 208  * End:
 209  *
 210  * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 211  * :indentSize=8:tabSize=8:noTabs=false:
 212  */