epan/dissectors/packet-ipfc.c

   1 /* packet-ipfc.c
   2  * Routines for Decoding Network_Header for IP-over-FC when we only
   3  * capture the frame starting at the Network_Header (as opposed to
   4  * when we have the full FC frame).
   5  * See RFC 2625.
   6  * Copyright 2001, Dinesh G Dutt <ddutt@cisco.com>
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * SPDX-License-Identifier: GPL-2.0-or-later
  13  */
  14
  15 #include "config.h"
  16
  17 #include <epan/packet.h>
  18 #include <epan/capture_dissectors.h>
  19 #include <epan/to_str.h>
  20
  21 #include "packet-llc.h"
  22
  23 void proto_register_ipfc(void);
  24 void proto_reg_handoff_ipfc(void);
  25
  26 static dissector_handle_t ipfc_handle;
  27 static capture_dissector_handle_t ipfc_cap_handle;
  28
  29 /* Initialize the protocol and registered fields */
  30 static int proto_ipfc;
  31 static int hf_ipfc_network_da;
  32 static int hf_ipfc_network_sa;
  33
  34 /* Initialize the subtree pointers */
  35 static int ett_ipfc;
  36 static dissector_handle_t llc_handle;
  37 static capture_dissector_handle_t llc_cap_handle;
  38
  39 static bool
  40 capture_ipfc (const unsigned char *pd, int offset _U_, int len, capture_packet_info_t *cpinfo, const union wtap_pseudo_header *pseudo_header _U_)
  41 {
  42   if (!BYTES_ARE_IN_FRAME(0, len, 16))
  43     return false;
  44
  45   return call_capture_dissector(llc_cap_handle, pd, 16, len, cpinfo, pseudo_header);
  46 }
  47
  48 static int
  49 dissect_ipfc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  50 {
  51
  52 /* Set up structures needed to add the protocol subtree and manage it */
  53     proto_item *ti;
  54     proto_tree *ipfc_tree;
  55     int offset = 0;
  56     tvbuff_t *next_tvb;
  57
  58     /* Make entries in Protocol column and Info column on summary display */
  59     col_set_str(pinfo->cinfo, COL_PROTOCOL, "IP/FC");
  60
  61     if (tree) {
  62         ti = proto_tree_add_protocol_format (tree, proto_ipfc, tvb, offset, 16,
  63                                          "IP Over FC Network_Header");
  64         ipfc_tree = proto_item_add_subtree (ti, ett_ipfc);
  65
  66         proto_tree_add_item (ipfc_tree, hf_ipfc_network_da, tvb, offset, 8, ENC_NA);
  67         proto_tree_add_item (ipfc_tree, hf_ipfc_network_sa, tvb, offset+8, 8, ENC_NA);
  68     }
  69
  70     next_tvb = tvb_new_subset_remaining (tvb, 16);
  71     call_dissector(llc_handle, next_tvb, pinfo, tree);
  72     return tvb_captured_length(tvb);
  73 }
  74
  75 /* Register the protocol with Wireshark */
  76
  77 /* this format is require because a script is used to build the C function
  78    that calls all the protocol registration.
  79 */
  80
  81 void
  82 proto_register_ipfc (void)
  83 {
  84
  85 /* Setup list of header fields  See Section 1.6.1 for details*/
  86     static hf_register_info hf[] = {
  87         { &hf_ipfc_network_da,
  88           {"Network DA", "ipfc.nh.da", FT_FCWWN, BASE_NONE, NULL,
  89            0x0, NULL, HFILL}},
  90         { &hf_ipfc_network_sa,
  91           {"Network SA", "ipfc.nh.sa", FT_FCWWN, BASE_NONE, NULL,
  92            0x0, NULL, HFILL}},
  93     };
  94
  95     /* Setup protocol subtree array */
  96     static int *ett[] = {
  97         &ett_ipfc,
  98     };
  99
 100     /* Register the protocol name and description */
 101     proto_ipfc = proto_register_protocol("IP Over FC", "IPFC", "ipfc");
 102
 103     /* Required function calls to register the header fields and subtrees used */
 104     proto_register_field_array(proto_ipfc, hf, array_length(hf));
 105     proto_register_subtree_array(ett, array_length(ett));
 106
 107     ipfc_handle = register_dissector("ipfc", dissect_ipfc, proto_ipfc);
 108     ipfc_cap_handle = register_capture_dissector("ipfc", capture_ipfc, proto_ipfc);
 109 }
 110
 111 /* If this dissector uses sub-dissector registration add a registration routine.
 112    This format is required because a script is used to find these routines and
 113    create the code that calls these routines.
 114 */
 115 void
 116 proto_reg_handoff_ipfc (void)
 117 {
 118     dissector_add_uint("wtap_encap", WTAP_ENCAP_IP_OVER_FC, ipfc_handle);
 119
 120     llc_handle = find_dissector_add_dependency("llc", proto_ipfc);
 121     llc_cap_handle = find_capture_dissector("llc");
 122
 123     capture_dissector_add_uint("wtap_encap", WTAP_ENCAP_IP_OVER_FC, ipfc_cap_handle);
 124 }
 125
 126 /*
 127  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 128  *
 129  * Local variables:
 130  * c-basic-offset: 4
 131  * tab-width: 8
 132  * indent-tabs-mode: nil
 133  * End:
 134  *
 135  * vi: set shiftwidth=4 tabstop=8 expandtab:
 136  * :indentSize=4:tabSize=8:noTabs=true:
 137  */