/* packet-vrrp.c * Routines for the Virtual Router Redundancy Protocol (VRRP) * RFC2338 * * Heikki Vatiainen * * $Id: packet-vrrp.c,v 1.23 2002/03/28 07:40:54 itojun 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 #ifdef HAVE_SYS_TYPES_H # include #endif #ifdef HAVE_NETINET_IN_H #include #endif #include #include #include #include "ipproto.h" #include "in_cksum.h" static gint proto_vrrp = -1; static gint ett_vrrp = -1; static gint ett_vrrp_ver_type = -1; static gint hf_vrrp_ver_type = -1; static gint hf_vrrp_version = -1; static gint hf_vrrp_type = -1; static gint hf_vrrp_virt_rtr_id = -1; static gint hf_vrrp_prio = -1; static gint hf_vrrp_count_ip = -1; static gint hf_vrrp_auth_type = -1; static gint hf_vrrp_adver_int = -1; static gint hf_vrrp_ip = -1; static gint hf_vrrp_ip6 = -1; #define VRRP_VERSION_MASK 0xf0 #define VRRP_TYPE_MASK 0x0f #define VRRP_AUTH_DATA_LEN 8 #define VRRP_TYPE_ADVERTISEMENT 1 static const value_string vrrp_type_vals[] = { {VRRP_TYPE_ADVERTISEMENT, "Advertisement"}, {0, NULL} }; #define VRRP_AUTH_TYPE_NONE 0 #define VRRP_AUTH_TYPE_SIMPLE_TEXT 1 #define VRRP_AUTH_TYPE_IP_AUTH_HDR 2 static const value_string vrrp_auth_vals[] = { {VRRP_AUTH_TYPE_NONE, "No Authentication"}, {VRRP_AUTH_TYPE_SIMPLE_TEXT, "Simple Text Authentication"}, {VRRP_AUTH_TYPE_IP_AUTH_HDR, "IP Authentication Header"}, {0, NULL} }; #define VRRP_PRIORITY_MASTER_STOPPING 0 /* Values between 1 and 254 inclusive are for backup VRRP routers */ #define VRRP_PRIORITY_DEFAULT 100 #define VRRP_PRIORITY_OWNER 255 static const value_string vrrp_prio_vals[] = { {VRRP_PRIORITY_MASTER_STOPPING, "Current Master has stopped participating in VRRP"}, {VRRP_PRIORITY_DEFAULT, "Default priority for a backup VRRP router"}, {VRRP_PRIORITY_OWNER, "This VRRP router owns the virtual router's IP address(es)"}, {0, NULL } }; static void dissect_vrrp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { int offset = 0; gint vrrp_len; guint8 ver_type; vec_t cksum_vec[4]; guint32 phdr[2]; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "VRRP"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); ver_type = tvb_get_guint8(tvb, 0); if (check_col(pinfo->cinfo, COL_INFO)) { col_add_fstr(pinfo->cinfo, COL_INFO, "%s (v%u)", "Announcement", hi_nibble(ver_type)); } if (tree) { proto_item *ti, *tv; proto_tree *vrrp_tree, *ver_type_tree; guint8 priority, ip_count = 0, auth_type; guint16 cksum, computed_cksum; guint8 auth_buf[VRRP_AUTH_DATA_LEN+1]; ti = proto_tree_add_item(tree, proto_vrrp, tvb, 0, -1, FALSE); vrrp_tree = proto_item_add_subtree(ti, ett_vrrp); tv = proto_tree_add_uint_format(vrrp_tree, hf_vrrp_ver_type, tvb, offset, 1, ver_type, "Version %u, Packet type %u (%s)", hi_nibble(ver_type), lo_nibble(ver_type), val_to_str(lo_nibble(ver_type), vrrp_type_vals, "Unknown")); ver_type_tree = proto_item_add_subtree(tv, ett_vrrp_ver_type); proto_tree_add_uint(ver_type_tree, hf_vrrp_version, tvb, offset, 1, ver_type); proto_tree_add_uint(ver_type_tree, hf_vrrp_type, tvb, offset, 1, ver_type); offset++; proto_tree_add_item(vrrp_tree, hf_vrrp_virt_rtr_id, tvb, offset, 1, FALSE); offset++; priority = tvb_get_guint8(tvb, offset); proto_tree_add_uint_format(vrrp_tree, hf_vrrp_prio, tvb, offset, 1, priority, "Priority: %u (%s)", priority, val_to_str(priority, vrrp_prio_vals, "Non-default backup priority")); offset++; switch(hi_nibble(ver_type)) { case 3: /* Skip reserve field */ offset++; break; case 2: default: ip_count = tvb_get_guint8(tvb, offset); proto_tree_add_uint(vrrp_tree, hf_vrrp_count_ip, tvb, offset, 1, ip_count); offset++; break; } auth_type = tvb_get_guint8(tvb, offset); proto_tree_add_item(vrrp_tree, hf_vrrp_auth_type, tvb, offset, 1, FALSE); offset++; proto_tree_add_item(vrrp_tree, hf_vrrp_adver_int, tvb, offset, 1, FALSE); offset++; cksum = tvb_get_ntohs(tvb, offset); vrrp_len = (gint)tvb_reported_length(tvb); if (!pinfo->fragmented && (gint)tvb_length(tvb) >= vrrp_len) { /* The packet isn't part of a fragmented datagram and isn't truncated, so we can checksum it. */ switch(hi_nibble(ver_type)) { case 3: /* Set up the fields of the pseudo-header. */ cksum_vec[0].ptr = pinfo->src.data; cksum_vec[0].len = pinfo->src.len; cksum_vec[1].ptr = pinfo->dst.data; cksum_vec[1].len = pinfo->dst.len; cksum_vec[2].ptr = (const guint8 *)&phdr; phdr[0] = htonl(vrrp_len); phdr[1] = htonl(IP_PROTO_VRRP); cksum_vec[2].len = 8; cksum_vec[3].ptr = tvb_get_ptr(tvb, 0, vrrp_len); cksum_vec[3].len = vrrp_len; computed_cksum = in_cksum(cksum_vec, 4); break; case 2: default: cksum_vec[0].ptr = tvb_get_ptr(tvb, 0, vrrp_len); cksum_vec[0].len = vrrp_len; computed_cksum = in_cksum(&cksum_vec[0], 1); break; } if (computed_cksum == 0) { proto_tree_add_text(vrrp_tree, tvb, offset, 2, "Checksum: 0x%04x (correct)", cksum); } else { proto_tree_add_text(vrrp_tree, tvb, offset, 2, "Checksum: 0x%04x (incorrect, should be 0x%04x)", cksum, in_cksum_shouldbe(cksum, computed_cksum)); } } else { proto_tree_add_text(vrrp_tree, tvb, offset, 2, "Checksum: 0x%04x", cksum); } offset+=2; switch(hi_nibble(ver_type)) { case 3: proto_tree_add_item(vrrp_tree, hf_vrrp_ip6, tvb, offset, 16, FALSE); offset+=16; break; case 2: default: while (ip_count > 0) { proto_tree_add_item(vrrp_tree, hf_vrrp_ip, tvb, offset, 4, FALSE); offset+=4; ip_count--; } break; } if (auth_type != VRRP_AUTH_TYPE_SIMPLE_TEXT) return; /* Contents of the authentication data is undefined */ tvb_get_nstringz0(tvb, offset, VRRP_AUTH_DATA_LEN, auth_buf); if (auth_buf[0] != '\0') proto_tree_add_text(vrrp_tree, tvb, offset, VRRP_AUTH_DATA_LEN, "Authentication string: `%s'", auth_buf); offset+=8; } } void proto_register_vrrp(void) { static hf_register_info hf[] = { { &hf_vrrp_ver_type, {"VRRP message version and type", "vrrp.typever", FT_UINT8, BASE_DEC, NULL, 0x0, "VRRP version and type", HFILL }}, { &hf_vrrp_version, {"VRRP protocol version", "vrrp.version", FT_UINT8, BASE_DEC, NULL, VRRP_VERSION_MASK, "VRRP version", HFILL }}, { &hf_vrrp_type, {"VRRP packet type", "vrrp.type", FT_UINT8, BASE_DEC, VALS(vrrp_type_vals), VRRP_TYPE_MASK, "VRRP type", HFILL }}, { &hf_vrrp_virt_rtr_id, {"Virtual Rtr ID", "vrrp.virt_rtr_id", FT_UINT8, BASE_DEC, NULL, 0x0, "Virtual router this packet is reporting status for", HFILL }}, { &hf_vrrp_prio, {"Priority", "vrrp.prio", FT_UINT8, BASE_DEC, NULL, 0x0, "Sending VRRP router's priority for the virtual router", HFILL }}, { &hf_vrrp_count_ip, {"Count IP Addrs", "vrrp.count_ip_addrs", FT_UINT8, BASE_DEC, NULL, 0x0, "The number of IP addresses contained in this VRRP advertisement", HFILL }}, { &hf_vrrp_auth_type, {"Auth Type", "vrrp.auth_type", FT_UINT8, BASE_DEC, VALS(vrrp_auth_vals), 0x0, "The authentication method being utilized", HFILL }}, { &hf_vrrp_adver_int, {"Adver Int", "vrrp.adver_int", FT_UINT8, BASE_DEC, NULL, 0x0, "Time interval (in seconds) between ADVERTISEMENTS", HFILL }}, { &hf_vrrp_ip, {"IP Address", "vrrp.ip_addr", FT_IPv4, 0, NULL, 0x0, "IP address associated with the virtual router", HFILL }}, { &hf_vrrp_ip6, {"IPv6 Address", "vrrp.ipv6_addr", FT_IPv6, 0, NULL, 0x0, "IPv6 address associated with the virtual router", HFILL }}, }; static gint *ett[] = { &ett_vrrp, &ett_vrrp_ver_type }; proto_vrrp = proto_register_protocol("Virtual Router Redundancy Protocol", "VRRP", "vrrp"); proto_register_field_array(proto_vrrp, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); return; } void proto_reg_handoff_vrrp(void) { dissector_handle_t vrrp_handle; vrrp_handle = create_dissector_handle(dissect_vrrp, proto_vrrp); dissector_add("ip.proto", IP_PROTO_VRRP, vrrp_handle); }