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  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * SPDX-License-Identifier: GPL-2.0-or-later
  11  *
  12  * Ref https://www.opennetworking.org/sdn-resources/onf-specifications/openflow
  13  */
  14
  15 #include "config.h"
  16
  17 #include <epan/packet.h>
  18 #include <epan/expert.h>
  19 #include <epan/prefs.h>
  20
  21 #include "packet-tcp.h"
  22
  23 void proto_register_openflow(void);
  24 void proto_reg_handoff_openflow(void);
  25
  26 #define OFP_LEGACY_PORT 6633
  27 #define OFP_LEGACY2_PORT 6634
  28 #define OFP_IANA_PORT 6653
  29 static range_t *g_openflow_ports;
  30
  31 static dissector_handle_t openflow_handle;
  32 static dissector_handle_t openflow_v1_handle;
  33 static dissector_handle_t openflow_v4_handle;
  34 static dissector_handle_t openflow_v5_handle;
  35 static dissector_handle_t openflow_v6_handle;
  36
  37 /* Initialize the protocol and registered fields */
  38 static int proto_openflow;
  39 static int hf_openflow_version;
  40
  41 static expert_field ei_openflow_version;
  42
  43 static bool openflow_desegment = true;
  44
  45 #define OFP_VERSION_1_0 1
  46 #define OFP_VERSION_1_1 2
  47 #define OFP_VERSION_1_2 3
  48 #define OFP_VERSION_1_3 4
  49 #define OFP_VERSION_1_4 5
  50 #define OFP_VERSION_1_5 6
  51
  52 static const value_string openflow_version_values[] = {
  53     { OFP_VERSION_1_0, "1.0" },
  54     { OFP_VERSION_1_1, "1.1" },
  55     { OFP_VERSION_1_2, "1.2" },
  56     { OFP_VERSION_1_3, "1.3" },
  57     { OFP_VERSION_1_4, "1.4" },
  58     { OFP_VERSION_1_5, "1.5" },
  59     { 0, NULL }
  60 };
  61
  62 static unsigned
  63 get_openflow_pdu_length(packet_info *pinfo _U_, tvbuff_t *tvb,
  64                         int offset, void *data _U_)
  65 {
  66     return tvb_get_ntohs(tvb, offset + 2);
  67 }
  68
  69 static int
  70 dissect_openflow_tcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  71 {
  72     unsigned offset = 0;
  73     uint8_t version;
  74     proto_item* ti;
  75
  76     version = tvb_get_uint8(tvb, 0);
  77     /* Set the Protocol column to the constant string of openflow */
  78     col_set_str(pinfo->cinfo, COL_PROTOCOL, "OpenFlow");
  79     col_clear(pinfo->cinfo,COL_INFO);
  80
  81     switch(version){
  82     case OFP_VERSION_1_0:
  83         call_dissector(openflow_v1_handle, tvb, pinfo, tree);
  84         break;
  85     case OFP_VERSION_1_3:
  86         call_dissector(openflow_v4_handle, tvb, pinfo, tree);
  87         break;
  88     case OFP_VERSION_1_4:
  89         call_dissector(openflow_v5_handle, tvb, pinfo, tree);
  90         break;
  91     case OFP_VERSION_1_5:
  92         call_dissector(openflow_v6_handle, tvb, pinfo, tree);
  93         break;
  94     default:
  95         ti = proto_tree_add_item(tree, hf_openflow_version, tvb, offset, 1, ENC_BIG_ENDIAN);
  96         expert_add_info(pinfo, ti, &ei_openflow_version);
  97         break;
  98     }
  99     return tvb_reported_length(tvb);
 100 }
 101
 102 #define OFP_HEADER_LEN  8
 103 static int
 104 dissect_openflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 105 {
 106     tcp_dissect_pdus(tvb, pinfo, tree, openflow_desegment, OFP_HEADER_LEN,
 107                      get_openflow_pdu_length, dissect_openflow_tcp_pdu, data);
 108     return tvb_captured_length(tvb);
 109 }
 110
 111 static bool
 112 dissect_openflow_heur(tvbuff_t *tvb, packet_info *pinfo,
 113                      proto_tree *tree, void *data)
 114 {
 115     conversation_t *conversation = NULL;
 116
 117     if ((pinfo->destport != OFP_LEGACY_PORT) &&
 118         (pinfo->destport != OFP_LEGACY2_PORT) &&
 119         (pinfo->destport != OFP_IANA_PORT) &&
 120         (!value_is_in_range(g_openflow_ports, pinfo->destport))) {
 121         return false;
 122     }
 123
 124     conversation = find_or_create_conversation(pinfo);
 125     conversation_set_dissector(conversation, openflow_handle);
 126
 127     dissect_openflow(tvb, pinfo, tree, data);
 128     return true;
 129 }
 130
 131 static void
 132 apply_openflow_prefs(void)
 133 {
 134     /* Openflow uses the port preference for heuristics */
 135     g_openflow_ports = prefs_get_range_value("openflow", "tcp.port");
 136 }
 137
 138 /*
 139  * Register the protocol with Wireshark.
 140  */
 141 void
 142 proto_register_openflow(void)
 143 {
 144     static hf_register_info hf[] = {
 145         { &hf_openflow_version,
 146             { "Version", "openflow.version",
 147                FT_UINT8, BASE_HEX, VALS(openflow_version_values), 0x7f,
 148                NULL, HFILL }
 149         }
 150     };
 151
 152     static ei_register_info ei[] = {
 153         { &ei_openflow_version, { "openflow.version.unknown", PI_UNDECODED, PI_WARN, "Unsupported version not dissected", EXPFILL }},
 154     };
 155
 156     module_t *openflow_module;
 157     expert_module_t* expert_openflow;
 158
 159     /* Register the protocol name and description */
 160     proto_openflow = proto_register_protocol("OpenFlow", "OpenFlow", "openflow");
 161
 162     openflow_handle = register_dissector("openflow", dissect_openflow, proto_openflow);
 163
 164     /* Required function calls to register the header fields and subtrees */
 165     proto_register_field_array(proto_openflow, hf, array_length(hf));
 166     expert_openflow = expert_register_protocol(proto_openflow);
 167     expert_register_field_array(expert_openflow, ei, array_length(ei));
 168
 169     openflow_module = prefs_register_protocol(proto_openflow, apply_openflow_prefs);
 170
 171     /* Register heuristic preference */
 172     prefs_register_obsolete_preference(openflow_module, "heuristic");
 173
 174     /* Register desegment preference */
 175     prefs_register_bool_preference(openflow_module, "desegment",
 176                                   "Reassemble OpenFlow messages spanning multiple TCP segments",
 177                                   "Whether the OpenFlow dissector should reassemble messages spanning multiple TCP segments."
 178                                   " To use this option, you must also enable \"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.",
 179                                   &openflow_desegment);
 180 }
 181
 182 void
 183 proto_reg_handoff_openflow(void)
 184 {
 185     heur_dissector_add("tcp", dissect_openflow_heur, "OpenFlow over TCP", "openflow_tcp", proto_openflow, HEURISTIC_ENABLE);
 186
 187     dissector_add_uint_with_preference("tcp.port", OFP_IANA_PORT, openflow_handle);
 188
 189     openflow_v1_handle = find_dissector_add_dependency("openflow_v1", proto_openflow);
 190     openflow_v4_handle = find_dissector_add_dependency("openflow_v4", proto_openflow);
 191     openflow_v5_handle = find_dissector_add_dependency("openflow_v5", proto_openflow);
 192     openflow_v6_handle = find_dissector_add_dependency("openflow_v6", proto_openflow);
 193     apply_openflow_prefs();
 194 }
 195
 196 /*
 197  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 198  *
 199  * Local variables:
 200  * c-basic-offset: 4
 201  * tab-width: 8
 202  * indent-tabs-mode: nil
 203  * End:
 204  *
 205  * vi: set shiftwidth=4 tabstop=8 expandtab:
 206  * :indentSize=4:tabSize=8:noTabs=true:
 207  */