/* packet-auto_rp.c * Routines for the Cisco Auto-RP protocol * ftp://ftpeng.cisco.com/ftp/ipmulticast/specs/pim-autorp-spec01.txt * * Heikki Vatiainen * * $Id: packet-auto_rp.c,v 1.23 2003/01/31 03:17:45 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include static gint proto_auto_rp = -1; static gint ett_auto_rp = -1; static gint ett_auto_rp_ver_type = -1; static gint ett_auto_rp_map = -1; static gint ett_auto_rp_group = -1; static gint hf_auto_rp_version = -1; static gint hf_auto_rp_type = -1; static gint hf_auto_rp_count = -1; static gint hf_auto_rp_holdtime = -1; static gint hf_auto_rp_pim_ver = -1; static gint hf_auto_rp_rp_addr = -1; static gint hf_auto_rp_prefix_sgn = -1; static gint hf_auto_rp_mask_len = -1; static gint hf_auto_rp_group_prefix = -1; #define UDP_PORT_PIM_RP_DISC 496 struct auto_rp_fixed_hdr { #define AUTO_RP_VERSION_MASK 0xf0 #define AUTO_RP_TYPE_MASK 0x0f guint8 ver_type; /* pim-autorp-spec01.txt defines version 1+ */ guint8 rp_count; /* Number of struct auto_rp_maps that follow the this header */ guint16 holdtime; /* Time in seconds this announcement is valid. 0 equals forever */ guint32 reserved; }; struct auto_rp_map_hdr { guint32 rp_address; /* The unicast IPv4 address of this RP */ #define AUTO_RP_PIM_VER_MASK 0x03 guint8 pim_version; /* RP's highest PIM version. 2-bit field */ guint8 group_count; /* Number of encoded group addresses that follow this header */ }; struct auto_rp_enc_grp_hdr { /* Encoded group address */ #define AUTO_RP_SIGN_MASK 0x01 guint8 prefix_sgn; /* 0 positive, 1 negative group prefix */ guint8 mask_len; /* Length of group prefix */ guint32 addr; /* Group prefix */ }; #define AUTO_RP_VER_1PLUS 1 static const value_string auto_rp_ver_vals[] = { {AUTO_RP_VER_1PLUS, "1 or 1+"}, {0, NULL} }; #define AUTO_RP_TYPE_ANNOUNCEMENT 1 #define AUTO_RP_TYPE_MAPPING 2 static const value_string auto_rp_type_vals[] = { {AUTO_RP_TYPE_ANNOUNCEMENT, "RP announcement"}, {AUTO_RP_TYPE_MAPPING, "RP mapping"}, {0, NULL} }; #define AUTO_RP_PIM_VERSION_UNKNOWN 0x00 #define AUTO_RP_PIM_VERSION_1 0x01 #define AUTO_RP_PIM_VERSION_2 0x02 #define AUTO_RP_PIM_VERSION_DUAL 0x03 static const value_string auto_rp_pim_ver_vals[] = { {AUTO_RP_PIM_VERSION_UNKNOWN, "Version unknown"}, {AUTO_RP_PIM_VERSION_1, "Version 1"}, {AUTO_RP_PIM_VERSION_2, "Version 2"}, {AUTO_RP_PIM_VERSION_DUAL, "Dual version 1 and 2"}, {0, NULL} }; #define AUTO_RP_GROUP_MASK_SIGN_POS 0 #define AUTO_RP_GROUP_MASK_SIGN_NEG 1 static const value_string auto_rp_mask_sign_vals[] = { {AUTO_RP_GROUP_MASK_SIGN_POS, "Positive group prefix"}, {AUTO_RP_GROUP_MASK_SIGN_NEG, "Negative group prefix"}, {0, NULL} }; static int do_auto_rp_map(tvbuff_t *tvb, int offset, proto_tree *auto_rp_tree); static void dissect_auto_rp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { guint8 ver_type, rp_count; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "Auto-RP"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); ver_type = tvb_get_guint8(tvb, 0); rp_count = tvb_get_guint8(tvb, 1); if (check_col(pinfo->cinfo, COL_INFO)) col_add_fstr(pinfo->cinfo, COL_INFO, "%s (v%s) for %u RP%s", val_to_str(lo_nibble(ver_type), auto_rp_type_vals, "Unknown"), val_to_str(hi_nibble(ver_type), auto_rp_ver_vals, "Unknown"), rp_count, plurality(rp_count, "", "s")); if (tree) { proto_item *ti, *tv; proto_tree *auto_rp_tree, *ver_type_tree; int i, offset; guint16 holdtime; offset = 0; ti = proto_tree_add_item(tree, proto_auto_rp, tvb, offset, -1, FALSE); auto_rp_tree = proto_item_add_subtree(ti, ett_auto_rp); tv = proto_tree_add_text(auto_rp_tree, tvb, offset, 1, "Version: %s, Packet type: %s", val_to_str(hi_nibble(ver_type), auto_rp_ver_vals, "Unknown"), val_to_str(lo_nibble(ver_type), auto_rp_type_vals, "Unknown")); ver_type_tree = proto_item_add_subtree(tv, ett_auto_rp_ver_type); proto_tree_add_uint(ver_type_tree, hf_auto_rp_version, tvb, offset, 1, ver_type); proto_tree_add_uint(ver_type_tree, hf_auto_rp_type, tvb, offset, 1, ver_type); offset++; proto_tree_add_uint(auto_rp_tree, hf_auto_rp_count, tvb, offset, 1, rp_count); offset++; holdtime = tvb_get_ntohs(tvb, offset); proto_tree_add_uint_format(auto_rp_tree, hf_auto_rp_holdtime, tvb, offset, 2, holdtime, "Holdtime: %u second%s", holdtime, plurality(holdtime, "", "s")); offset+=2; proto_tree_add_text(auto_rp_tree, tvb, offset, 4, "Reserved: 0x%x", tvb_get_ntohs(tvb, offset)); offset+=4; for (i = 0; i < rp_count; i++) offset = do_auto_rp_map(tvb, offset, auto_rp_tree); if (tvb_offset_exists(tvb, offset)) proto_tree_add_text(tree, tvb, offset, -1, "Trailing junk"); } return; } void proto_register_auto_rp(void) { static hf_register_info hf[] = { { &hf_auto_rp_version, {"Protocol version", "auto_rp.version", FT_UINT8, BASE_DEC, VALS(auto_rp_ver_vals), AUTO_RP_VERSION_MASK, "Auto-RP protocol version", HFILL }}, { &hf_auto_rp_type, {"Packet type", "auto_rp.type", FT_UINT8, BASE_DEC, VALS(auto_rp_type_vals), AUTO_RP_TYPE_MASK, "Auto-RP packet type", HFILL }}, { &hf_auto_rp_count, {"RP count", "auto_rp.rp_count", FT_UINT8, BASE_DEC, NULL, 0, "The number of RP addresses contained in this message", HFILL }}, { &hf_auto_rp_holdtime, {"Holdtime", "auto_rp.holdtime", FT_UINT16, BASE_DEC, NULL, 0, "The amount of time in seconds this announcement is valid", HFILL }}, { &hf_auto_rp_pim_ver, {"Version", "auto_rp.pim_ver", FT_UINT8, BASE_DEC, VALS(auto_rp_pim_ver_vals), AUTO_RP_PIM_VER_MASK, "RP's highest PIM version", HFILL }}, { &hf_auto_rp_rp_addr, {"RP address", "auto_rp.rp_addr", FT_IPv4, 0, NULL, 0, "The unicast IP address of the RP", HFILL }}, { &hf_auto_rp_prefix_sgn, {"Sign", "auto_rp.prefix_sign", FT_UINT8, BASE_DEC, VALS(auto_rp_mask_sign_vals), AUTO_RP_SIGN_MASK, "Group prefix sign", HFILL }}, { &hf_auto_rp_mask_len, {"Mask length", "auto_rp.mask_len", FT_UINT8, BASE_DEC, NULL, 0x0, "Length of group prefix", HFILL }}, { &hf_auto_rp_group_prefix, {"Prefix", "auto_rp.group_prefix", FT_IPv4, 0, NULL, 0, "Group prefix", HFILL }} }; static gint *ett[] = { &ett_auto_rp, &ett_auto_rp_ver_type, &ett_auto_rp_map, &ett_auto_rp_group }; proto_auto_rp = proto_register_protocol("Cisco Auto-RP", "Auto-RP", "auto_rp"); proto_register_field_array(proto_auto_rp, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); return; } void proto_reg_handoff_auto_rp(void) { dissector_handle_t auto_rp_handle; auto_rp_handle = create_dissector_handle(dissect_auto_rp, proto_auto_rp); dissector_add("udp.port", UDP_PORT_PIM_RP_DISC, auto_rp_handle); } /* * Handles one Auto-RP map entry. Returns the new offset. */ static int do_auto_rp_map(tvbuff_t *tvb, int offset, proto_tree *auto_rp_tree) { proto_item *ti; proto_tree *map_tree; guint8 group_count; guint32 rp_addr; /* In network byte order */ int i; tvb_memcpy(tvb, (guint8 *)&rp_addr, offset, 4); group_count = tvb_get_guint8(tvb, offset + 5); /* sizeof map header + n * sizeof encoded group addresses */ ti = proto_tree_add_text(auto_rp_tree, tvb, offset, 6 + group_count * 6, "RP %s: %u group%s", ip_to_str((void *)&rp_addr), group_count, plurality(group_count, "", "s")); map_tree = proto_item_add_subtree(ti, ett_auto_rp_map); proto_tree_add_ipv4(map_tree, hf_auto_rp_rp_addr, tvb, offset, 4, rp_addr); offset += 4; proto_tree_add_uint(map_tree, hf_auto_rp_pim_ver, tvb, offset, 1, tvb_get_guint8(tvb, offset)); offset++; proto_tree_add_text(map_tree, tvb, offset, 1, "Number of groups this RP maps to: %u", group_count); offset++; for (i = 0; i < group_count; i++) { proto_item *gi; proto_tree *grp_tree; guint8 sign, mask_len; guint32 group_addr; /* In network byte order */ sign = tvb_get_guint8(tvb, offset); mask_len = tvb_get_guint8(tvb, offset + 1); tvb_memcpy(tvb, (guint8 *)&group_addr, offset + 2, 4); gi = proto_tree_add_text(map_tree, tvb, offset, 6, "Group %s/%u (%s)", ip_to_str((void *)&group_addr), mask_len, val_to_str(sign&AUTO_RP_SIGN_MASK, auto_rp_mask_sign_vals, "")); grp_tree = proto_item_add_subtree(gi, ett_auto_rp_group); proto_tree_add_uint(grp_tree, hf_auto_rp_prefix_sgn, tvb, offset, 1, sign); offset++; proto_tree_add_uint(grp_tree, hf_auto_rp_mask_len, tvb, offset, 1, mask_len); offset++; proto_tree_add_ipv4(grp_tree, hf_auto_rp_group_prefix, tvb, offset, 4, group_addr); offset += 4; } return offset; }