diff options
Diffstat (limited to 'epan/dissectors/packet-ieee802a.c')
| -rw-r--r-- | epan/dissectors/packet-ieee802a.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/epan/dissectors/packet-ieee802a.c b/epan/dissectors/packet-ieee802a.c new file mode 100644 index 00000000..450abb8a --- /dev/null +++ b/epan/dissectors/packet-ieee802a.c @@ -0,0 +1,186 @@ +/* packet-ieee802a.c + * Routines for IEEE 802a + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/addr_resolv.h> +#include <epan/etypes.h> + +#include "packet-ieee802a.h" + +void proto_register_ieee802a(void); +void proto_reg_handoff_ieee802a(void); + +static dissector_handle_t ieee802a_handle; + +static int proto_ieee802a = -1; +static int hf_ieee802a_oui = -1; +static int hf_ieee802a_pid = -1; + +static gint ett_ieee802a = -1; + +/* + * Hash table for translating OUIs to a dissector table/field info pair; + * the dissector table maps PID values to dissectors, and the field + * corresponds to the PID for that OUI. + */ +typedef struct { + dissector_table_t table; + hf_register_info *field_info; +} oui_info_t; + +static GHashTable *oui_info_table = NULL; + +/* + * Add an entry for a new OUI. + */ +void +ieee802a_add_oui(guint32 oui, const char *table_name, const char *table_ui_name, + hf_register_info *hf_item, const int proto) +{ + oui_info_t *new_info; + + new_info = g_new(oui_info_t, 1); + new_info->table = register_dissector_table(table_name, + table_ui_name, proto, FT_UINT16, BASE_HEX); + new_info->field_info = hf_item; + + /* + * Create the hash table for OUI information, if it doesn't + * already exist. + */ + if (oui_info_table == NULL) { + oui_info_table = g_hash_table_new_full(g_direct_hash, + g_direct_equal, NULL, g_free); + } + g_hash_table_insert(oui_info_table, GUINT_TO_POINTER(oui), new_info); +} + +static int +dissect_ieee802a(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) +{ + proto_tree *ieee802a_tree; + proto_item *ti; + tvbuff_t *next_tvb; + const gchar *manuf; + guint32 oui32; + guint16 pid; + oui_info_t *oui_info; + dissector_table_t subdissector_table; + int hf; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "IEEE802a"); + col_clear(pinfo->cinfo, COL_INFO); + + ti = proto_tree_add_item(tree, proto_ieee802a, tvb, 0, 5, ENC_NA); + ieee802a_tree = proto_item_add_subtree(ti, ett_ieee802a); + + proto_tree_add_item_ret_uint(ieee802a_tree, hf_ieee802a_oui, tvb, 0, 3, ENC_BIG_ENDIAN, &oui32); + manuf = uint_get_manuf_name_if_known(oui32); + pid = tvb_get_ntohs(tvb, 3); + + col_add_fstr(pinfo->cinfo, COL_INFO, "OUI %s (%s), PID 0x%04X", + tvb_bytes_to_str_punct(pinfo->pool, tvb, 0, 3, ':'), + manuf ? manuf : "Unknown", pid); + + /* + * Do we have information for this OUI? + */ + if (oui_info_table != NULL && + (oui_info = (oui_info_t *)g_hash_table_lookup(oui_info_table, + GUINT_TO_POINTER(oui32))) != NULL) { + /* + * Yes - use it. + */ + hf = *oui_info->field_info->p_id; + subdissector_table = oui_info->table; + } else { + /* + * No, use hf_ieee802a_pid for the PID and just dissect + * the payload as data. + */ + hf = hf_ieee802a_pid; + subdissector_table = NULL; + } + + proto_tree_add_uint(ieee802a_tree, hf, tvb, 3, 2, pid); + next_tvb = tvb_new_subset_remaining(tvb, 5); + if ((subdissector_table == NULL) || + /* do lookup with the subdissector table */ + (!dissector_try_uint(subdissector_table, pid, next_tvb, pinfo, tree))) { + call_data_dissector(next_tvb, pinfo, tree); + } + return tvb_captured_length(tvb); +} + +static void +ieee802a_shutdown(void) +{ + g_hash_table_destroy(oui_info_table); +} + +void +proto_register_ieee802a(void) +{ + static hf_register_info hf[] = { + { &hf_ieee802a_oui, + { "Organization Code", "ieee802a.oui", FT_UINT24, BASE_OUI, + NULL, 0x0, NULL, HFILL }}, + + { &hf_ieee802a_pid, + { "Protocol ID", "ieee802a.pid", FT_UINT16, BASE_HEX, + NULL, 0x0, NULL, HFILL }} + }; + static gint *ett[] = { + &ett_ieee802a, + }; + + proto_ieee802a = proto_register_protocol("IEEE802a OUI Extended Ethertype", "IEEE802a", "ieee802a"); + proto_register_field_array(proto_ieee802a, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + register_shutdown_routine(ieee802a_shutdown); + + ieee802a_handle = register_dissector("ieee802a", dissect_ieee802a, proto_ieee802a); +} + +static void +register_hf(gpointer key _U_, gpointer value, gpointer user_data _U_) +{ + oui_info_t *info = (oui_info_t *)value; + + proto_register_field_array(proto_ieee802a, info->field_info, 1); +} + +void +proto_reg_handoff_ieee802a(void) +{ + dissector_add_uint("ethertype", ETHERTYPE_IEEE802_OUI_EXTENDED, + ieee802a_handle); + + /* + * Register all the fields for PIDs for various OUIs. + */ + if (oui_info_table != NULL) + g_hash_table_foreach(oui_info_table, register_hf, NULL); +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 8 + * tab-width: 8 + * indent-tabs-mode: t + * End: + * + * vi: set shiftwidth=8 tabstop=8 noexpandtab: + * :indentSize=8:tabSize=8:noTabs=false: + */ |