epan/dissectors/packet-openflow.c

   1 /* packet-openflow.c
   2  * Routines for OpenFlow dissection
   3  * Copyright 2013, Anders Broman <anders.broman@ericsson.com>
   4  * Copyright 2013, Zoltan Lajos Kis <zoltan.lajos.kis@ericsson.com>
   5  *
   6  * $Id$
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  25  *
  26  * Ref https://www.opennetworking.org/sdn-resources/onf-specifications/openflow
  27  */
  28
  29 #include "config.h"
  30
  31 #include <glib.h>
  32
  33 #include <epan/packet.h>
  34 #include <epan/prefs.h>
  35
  36 #include "packet-tcp.h"
  37
  38 void proto_register_openflow(void);
  39 void proto_reg_handoff_openflow(void);
  40
  41 static int g_openflow_port = 0;
  42
  43 static dissector_handle_t openflow_v1_handle;
  44 static dissector_handle_t openflow_v4_handle;
  45
  46 /* Initialize the protocol and registered fields */
  47 static int proto_openflow = -1;
  48 static int hf_openflow_version = -1;
  49
  50 static gboolean openflow_desegment = TRUE;
  51
  52 #define OFP_VERSION_1_0 1
  53 #define OFP_VERSION_1_1 2
  54 #define OFP_VERSION_1_2 3
  55 #define OFP_VERSION_1_3 4
  56
  57 static const value_string openflow_version_values[] = {
  58     { 0x01, "1.0" },
  59     { 0x02, "1.1" },
  60     { 0x03, "1.2" },
  61     { 0x04, "1.3.1" },
  62     { 0, NULL }
  63 };
  64
  65
  66 static guint
  67 get_openflow_pdu_length(packet_info *pinfo _U_, tvbuff_t *tvb, int offset)
  68 {
  69     return tvb_get_ntohs(tvb, offset + 2);
  70 }
  71
  72
  73 static int
  74 dissect_openflow_tcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  75 {
  76     guint offset = 0;
  77     guint8 version;
  78
  79     version = tvb_get_guint8(tvb, 0);
  80     /* Set the Protocol column to the constant string of openflow */
  81     col_set_str(pinfo->cinfo, COL_PROTOCOL, "OpenFlow");
  82     col_clear(pinfo->cinfo,COL_INFO);
  83
  84     switch(version){
  85     case OFP_VERSION_1_0:
  86         call_dissector(openflow_v1_handle, tvb, pinfo, tree);
  87         break;
  88     case OFP_VERSION_1_3:
  89         call_dissector(openflow_v4_handle, tvb, pinfo, tree);
  90         break;
  91     default:
  92         proto_tree_add_item(tree, hf_openflow_version, tvb, offset, 1, ENC_BIG_ENDIAN);
  93         proto_tree_add_text(tree, tvb, offset, -1, "Unsuported version not dissected");
  94         break;
  95     }
  96     return tvb_length(tvb);
  97 }
  98
  99
 100 #define OFP_HEADER_LEN  8
 101 static int
 102 dissect_openflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 103 {
 104     tcp_dissect_pdus(tvb, pinfo, tree, openflow_desegment, OFP_HEADER_LEN,
 105                      get_openflow_pdu_length, dissect_openflow_tcp_pdu, data);
 106     return tvb_length(tvb);
 107 }
 108
 109 /*
 110  * Register the protocol with Wireshark.
 111  */
 112 void
 113 proto_register_openflow(void)
 114 {
 115     static hf_register_info hf[] = {
 116         { &hf_openflow_version,
 117             { "Version", "openflow.version",
 118                FT_UINT8, BASE_HEX, VALS(openflow_version_values), 0x7f,
 119                NULL, HFILL }
 120         }
 121     };
 122
 123     module_t *openflow_module;
 124
 125     /* Register the protocol name and description */
 126     proto_openflow = proto_register_protocol("OpenFlow",
 127             "openflow", "openflow");
 128
 129     new_register_dissector("openflow", dissect_openflow, proto_openflow);
 130
 131     /* Required function calls to register the header fields and subtrees */
 132     proto_register_field_array(proto_openflow, hf, array_length(hf));
 133
 134     openflow_module = prefs_register_protocol(proto_openflow, proto_reg_handoff_openflow);
 135
 136     /* Register port preference */
 137     prefs_register_uint_preference(openflow_module, "tcp.port", "openflow TCP Port",
 138             " openflow TCP port if other than the default",
 139             10, &g_openflow_port);
 140
 141     /* Register desegment preference */
 142     prefs_register_bool_preference(openflow_module, "desegment",
 143                                   "Reassemble OpenFlow messages spanning multiple TCP segments",
 144                                   "Whether the OpenFlow dissector should reassemble messages spanning multiple TCP segments."
 145                                   " To use this option, you must also enable \"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.",
 146                                   &openflow_desegment);
 147 }
 148
 149 void
 150 proto_reg_handoff_openflow(void)
 151 {
 152     static gboolean initialized = FALSE;
 153     static dissector_handle_t openflow_handle;
 154     static int currentPort;
 155
 156     if (!initialized) {
 157         openflow_handle = new_create_dissector_handle(dissect_openflow, proto_openflow);
 158         initialized = TRUE;
 159
 160     } else {
 161         dissector_delete_uint("tcp.port", currentPort, openflow_handle);
 162     }
 163
 164     currentPort = g_openflow_port;
 165
 166     dissector_add_uint("tcp.port", currentPort, openflow_handle);
 167
 168     openflow_v1_handle = find_dissector("openflow_v1");
 169     openflow_v4_handle = find_dissector("openflow_v4");
 170
 171 }
 172
 173
 174 /*
 175  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 176  *
 177  * Local variables:
 178  * c-basic-offset: 4
 179  * tab-width: 8
 180  * indent-tabs-mode: nil
 181  * End:
 182  *
 183  * vi: set shiftwidth=4 tabstop=8 expandtab:
 184  * :indentSize=4:tabSize=8:noTabs=true:
 185  */