/* packet-dhpcv6.c * Routines for DHCPv6 packet disassembly * Jun-ichiro itojun Hagino * IItom Tsutomu MIENO * SHIRASAKI Yasuhiro * * $Id: packet-dhcpv6.c,v 1.7 2002/08/28 21:00:12 jmayer Exp $ * * The information used comes from: * draft-ietf-dhc-dhcpv6-26.txt * draft-troan-dhcpv6-opt-prefix-delegation-01.txt * draft-ietf-dhc-dhcpv6-opt-dnsconfig-02.txt * * Note that protocol constants are still subject to change, based on IANA * assignment decisions. * * 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 #include static int proto_dhcpv6 = -1; static int hf_dhcpv6_msgtype = -1; static guint ett_dhcpv6 = -1; static guint ett_dhcpv6_option = -1; #define UDP_PORT_DHCPV6_DOWNSTREAM 546 #define UDP_PORT_DHCPV6_UPSTREAM 547 #define DHCPV6_LEASEDURATION_INFINITY 0xffffffff #define SOLICIT 1 #define ADVERTISE 2 #define REQUEST 3 #define CONFIRM 4 #define RENEW 5 #define REBIND 6 #define REPLY 7 #define RELEASE 8 #define DECLINE 9 #define RECONFIGURE 10 #define INFORMATION_REQUEST 11 #define RELAY_FORW 12 #define RELAY_REPL 13 #define OPTION_CLIENTID 1 #define OPTION_SERVERID 2 #define OPTION_IA 3 #define OPTION_IA_TA 4 #define OPTION_IAADDR 5 #define OPTION_ORO 6 #define OPTION_PREFERENCE 7 #define OPTION_ELAPSED_TIME 8 #define OPTION_RELAY_MSG 9 /* #define OPTION_SERVER_MSG 10 */ #define OPTION_AUTH 11 #define OPTION_UNICAST 12 #define OPTION_STATUS_CODE 13 #define OPTION_RAPID_COMMIT 14 #define OPTION_USER_CLASS 15 #define OPTION_VENDOR_CLASS 16 #define OPTION_VENDOR_OPTS 17 #define OPTION_INTERFACE_ID 18 #define OPTION_RECONF_MSG 19 #define OPTION_RECONF_NONCE 20 #define OPTION_DNS_SERVERS 25 #define OPTION_DOMAIN_LIST 26 #define OPTION_PREFIXDEL 30 #define OPTION_PREFIX_INFO 31 #define OPTION_PREFIXREQ 32 #define DUID_LLT 1 #define DUID_EN 2 #define DUID_LL 3 #define DUID_LL_OLD 4 static const value_string msgtype_vals[] = { { SOLICIT, "Solicit" }, { ADVERTISE, "Advertise" }, { REQUEST, "Request" }, { CONFIRM, "Confirm" }, { RENEW, "Renew" }, { REBIND, "Rebind" }, { REPLY, "Reply" }, { RELEASE, "Release" }, { DECLINE, "Decline" }, { RECONFIGURE, "Reconfigure" }, { INFORMATION_REQUEST, "Information-request" }, { RELAY_FORW, "Relay-forw" }, { RELAY_REPL, "Relay-repl" }, { 0, NULL } }; static const value_string opttype_vals[] = { { OPTION_CLIENTID, "Client Identifier" }, { OPTION_SERVERID, "Server Identifier" }, { OPTION_IA, "Identify Association" }, { OPTION_IA_TA, "Identify Association for Temporary Address" }, { OPTION_IAADDR, "IA Address" }, { OPTION_ORO, "Option Request" }, { OPTION_PREFERENCE, "Preference" }, { OPTION_ELAPSED_TIME, "Elapsed time" }, { OPTION_RELAY_MSG, "Relay Message" }, /* { OPTION_SERVER_MSG, "Server message" }, */ { OPTION_AUTH, "Authentication" }, { OPTION_UNICAST, "Server unicast" }, { OPTION_STATUS_CODE, "Status code" }, { OPTION_RAPID_COMMIT, "Rapid Commit" }, { OPTION_USER_CLASS, "User Class" }, { OPTION_VENDOR_CLASS, "Vendor Class" }, { OPTION_VENDOR_OPTS, "Vendor-specific Information" }, { OPTION_INTERFACE_ID, "Interface-Id" }, { OPTION_RECONF_MSG, "Reconfigure Message" }, { OPTION_RECONF_NONCE, "Reconfigure Nonce" }, { OPTION_DNS_SERVERS, "Domain Name Server" }, { OPTION_DOMAIN_LIST, "Domain Search List" }, { OPTION_PREFIXDEL, "Prefix Delegation" }, { OPTION_PREFIX_INFO, "Prefix Information" }, { OPTION_PREFIXREQ, "Prefix Request" }, { 0, NULL } }; static const value_string statuscode_vals[] = { {0, "Success" }, {1, "UnspecFail" }, {2, "AuthFailed" }, {3, "AddrUnvail" }, {4, "NoAddrAvail" }, {5, "NoBinding" }, {6, "ConfNoMatch" }, {7, "NotOnLink" }, {8, "UseMulticast" }, {0, NULL } }; static const value_string duidtype_vals[] = { { DUID_LLT, "link-layer address plus time" }, { DUID_EN, "assigned by vendor based on Enterprise number" }, { DUID_LL, "link-layer address" }, { DUID_LL_OLD, "link-layer address (old)" }, { 0, NULL } }; /* Returns the number of bytes consumed by this option. */ static int dhcpv6_option(tvbuff_t *tvb, proto_tree *bp_tree, int off, int eoff, gboolean *at_end) { guint16 opttype; guint16 optlen; proto_item *ti; proto_tree *subtree; int i; struct e_in6_addr in6; guint16 duidtype; /* option type and length must be present */ if (eoff - off < 4) { *at_end = TRUE; return 0; } opttype = tvb_get_ntohs(tvb, off); optlen = tvb_get_ntohs(tvb, off + 2); /* truncated case */ if (eoff - off < 4 + optlen) { *at_end = TRUE; return 0; } ti = proto_tree_add_text(bp_tree, tvb, off, 4 + optlen, "%s", val_to_str(opttype, opttype_vals, "DHCP option %u")); subtree = proto_item_add_subtree(ti, ett_dhcpv6_option); proto_tree_add_text(subtree, tvb, off, 2, "option type: %d", opttype); proto_tree_add_text(subtree, tvb, off + 2, 2, "option length: %d", optlen); off += 4; switch (opttype) { case OPTION_CLIENTID: case OPTION_SERVERID: if (optlen < 2) { proto_tree_add_text(subtree, tvb, off, optlen, "DUID: malformed option"); break; } duidtype = tvb_get_ntohs(tvb, off); proto_tree_add_text(subtree, tvb, off, 2, "DUID type: %s (%u)", val_to_str(duidtype, duidtype_vals, "Unknown"), duidtype); switch (duidtype) { case DUID_LLT: if (optlen < 8) { proto_tree_add_text(subtree, tvb, off, optlen, "DUID: malformed option"); break; } /* XXX seconds since Jan 1 2000 */ proto_tree_add_text(subtree, tvb, off + 2, 2, "Hardware type: %u", tvb_get_ntohs(tvb, off + 2)); proto_tree_add_text(subtree, tvb, off + 4, 4, "Time: %u", tvb_get_ntohl(tvb, off + 4)); if (optlen > 8) { proto_tree_add_text(subtree, tvb, off + 8, optlen - 8, "Link-layer address"); } break; case DUID_EN: if (optlen < 6) { proto_tree_add_text(subtree, tvb, off, optlen, "DUID: malformed option"); break; } proto_tree_add_text(subtree, tvb, off + 2, 4, "enterprise-number"); if (optlen > 6) { proto_tree_add_text(subtree, tvb, off + 6, optlen - 6, "identifier"); } break; case DUID_LL: case DUID_LL_OLD: if (optlen < 4) { proto_tree_add_text(subtree, tvb, off, optlen, "DUID: malformed option"); break; } proto_tree_add_text(subtree, tvb, off + 2, 2, "Hardware type: %u", tvb_get_ntohs(tvb, off + 2)); if (optlen > 4) { proto_tree_add_text(subtree, tvb, off + 4, optlen - 4, "Link-layer address"); } break; } break; case OPTION_IA: if (optlen < 12) { proto_tree_add_text(subtree, tvb, off, optlen, "IA: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 4, "IAID: %u", tvb_get_ntohl(tvb, off)); proto_tree_add_text(subtree, tvb, off+4, 4, "T1: %u", tvb_get_ntohl(tvb, off+4)); proto_tree_add_text(subtree, tvb, off+8, 4, "T2: %u", tvb_get_ntohl(tvb, off+8)); if (optlen > 12) { gboolean at_end_; dhcpv6_option(tvb, subtree, off+12, off + optlen - 12, &at_end_); } break; case OPTION_IA_TA: if (optlen < 4) { proto_tree_add_text(subtree, tvb, off, optlen, "IA_TA: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 4, "IAID: %u", tvb_get_ntohl(tvb, off)); if (optlen > 4) { gboolean at_end_; dhcpv6_option(tvb, subtree, off+4, off + optlen - 4, &at_end_); } break; case OPTION_IAADDR: if (optlen < 24) { proto_tree_add_text(subtree, tvb, off, optlen, "IAADDR: malformed option"); break; } tvb_memcpy(tvb, (guint8 *)&in6, off, sizeof(in6)); proto_tree_add_text(subtree, tvb, off, sizeof(in6), "IPv6 address: %s", ip6_to_str(&in6)); proto_tree_add_text(subtree, tvb, off+16, 4, "preferred-lifetime: %u", tvb_get_ntohl(tvb, off+16)); proto_tree_add_text(subtree, tvb, off+20, 4, "valid-lifetime: %u", tvb_get_ntohl(tvb, off+20)); if (optlen > 24) { gboolean at_end_; dhcpv6_option(tvb, subtree, off+24, off + optlen - 24, &at_end_); } break; case OPTION_ORO: for (i = 0; i < optlen; i += 2) { guint16 requested_opt_code; requested_opt_code = tvb_get_ntohs(tvb, off + i); proto_tree_add_text(subtree, tvb, off + i, 2, "Requested Option code: %s (%d)", val_to_str(requested_opt_code, opttype_vals, "Unknown"), requested_opt_code); } break; case OPTION_PREFERENCE: if (optlen != 1) { proto_tree_add_text(subtree, tvb, off, optlen, "PREFERENCE: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 1, "pref-value: %d", (guint32)tvb_get_guint8(tvb, off)); break; case OPTION_ELAPSED_TIME: if (optlen != 2) { proto_tree_add_text(subtree, tvb, off, optlen, "ELAPSED-TIME: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 2, "elapsed-time: %d sec", (guint32)tvb_get_ntohs(tvb, off)); break; case OPTION_RELAY_MSG: if (optlen == 0) { proto_tree_add_text(subtree, tvb, off, optlen, "RELAY-MSG: malformed option"); break; } else { gboolean at_end_; dhcpv6_option(tvb, subtree, off, off + optlen, &at_end_); } break; case OPTION_AUTH: if (optlen < 15) { proto_tree_add_text(subtree, tvb, off, optlen, "AUTH: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 1, "Protocol: %d", (guint32)tvb_get_guint8(tvb, off)); proto_tree_add_text(subtree, tvb, off+1, 1, "Algorithm: %d", (guint32)tvb_get_guint8(tvb, off+1)); proto_tree_add_text(subtree, tvb, off+2, 1, "RDM: %d", (guint32)tvb_get_guint8(tvb, off+2)); proto_tree_add_text(subtree, tvb, off+3, 8, "Reply Detection"); proto_tree_add_text(subtree, tvb, off+11, optlen-11, "Authentication Information"); break; case OPTION_UNICAST: if (optlen != 16) { proto_tree_add_text(subtree, tvb, off, optlen, "UNICAST: malformed option"); break; } tvb_memcpy(tvb, (guint8 *)&in6, off, sizeof(in6)); proto_tree_add_text(subtree, tvb, off, sizeof(in6), "IPv6 address: %s", ip6_to_str(&in6)); break; case OPTION_STATUS_CODE: { guint16 status_code; char *status_message = 0; status_code = tvb_get_ntohs(tvb, off); proto_tree_add_text(subtree, tvb, off, 2, "Status Code: %s (%d)", val_to_str(status_code, statuscode_vals, "Unknown"), status_code); if (optlen - 2 > 0) status_message = g_malloc(optlen - 2 + 1); if (status_message != 0){ memset(status_message, 0, optlen - 2 + 1); status_message = tvb_memcpy(tvb, status_message, off + 2, optlen - 2); proto_tree_add_text(subtree, tvb, off + 2, optlen - 2, "Status Message: %s", status_message); g_free(status_message); } } break; case OPTION_VENDOR_CLASS: if (optlen < 4) { proto_tree_add_text(subtree, tvb, off, optlen, "VENDOR_CLASS: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 4, "enterprise-number: %u", tvb_get_ntohl(tvb, off)); if (optlen > 4) { proto_tree_add_text(subtree, tvb, off+4, optlen-4, "vendor-class-data"); } break; case OPTION_VENDOR_OPTS: if (optlen < 4) { proto_tree_add_text(subtree, tvb, off, optlen, "VENDOR_OPTS: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, 4, "enterprise-number: %u", tvb_get_ntohl(tvb, off)); if (optlen > 4) { proto_tree_add_text(subtree, tvb, off+4, optlen-4, "option-data"); } break; case OPTION_INTERFACE_ID: if (optlen == 0) { proto_tree_add_text(subtree, tvb, off, optlen, "INTERFACE_ID: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, optlen, "Interface-ID"); break; case OPTION_RECONF_MSG: if (optlen != 1) { proto_tree_add_text(subtree, tvb, off, optlen, "RECONF_MSG: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, optlen, "Reconfigure-type: %s", val_to_str(tvb_get_guint8(tvb, off), msgtype_vals, "Message Type %u")); break; case OPTION_RECONF_NONCE: if (optlen != 8) { proto_tree_add_text(subtree, tvb, off, optlen, "RECONF_NONCE: malformed option"); break; } proto_tree_add_text(subtree, tvb, off, optlen, "Reconfigure-nonce"); break; case OPTION_DNS_SERVERS: if (optlen % 16) { proto_tree_add_text(subtree, tvb, off, optlen, "DNS servers address: malformed option"); break; } for (i = 0; i < optlen; i += 16) { tvb_memcpy(tvb, (guint8 *)&in6, off + i, sizeof(in6)); proto_tree_add_text(subtree, tvb, off + i, sizeof(in6), "DNS servers address: %s", ip6_to_str(&in6)); } break; case OPTION_DOMAIN_LIST: if (optlen > 0) { proto_tree_add_text(subtree, tvb, off, optlen, "Search String"); } break; case OPTION_PREFIXDEL: { gboolean at_end_; dhcpv6_option(tvb, subtree, off, off + optlen, &at_end_); } break; case OPTION_PREFIX_INFO: { guint32 lease_duration; guint8 prefix_length; struct e_in6_addr in6; lease_duration = tvb_get_ntohl(tvb, off); prefix_length = tvb_get_guint8(tvb, off + 4); if ( lease_duration == DHCPV6_LEASEDURATION_INFINITY) { proto_tree_add_text(subtree, tvb, off, 4, "Lease duration: infinity"); } else { proto_tree_add_text(subtree, tvb, off, 4, "Lease duration: %u", lease_duration); } proto_tree_add_text(subtree, tvb, off + 4, 1, "Prefix length: %d", prefix_length); tvb_memcpy(tvb, (guint8 *)&in6, off + 5 , sizeof(in6)); proto_tree_add_text(subtree, tvb, off + 5, 16, "Prefix address: %s", ip6_to_str(&in6)); } break; case OPTION_PREFIXREQ: { guint8 prefix_length; prefix_length = tvb_get_guint8(tvb, off); proto_tree_add_text(subtree, tvb, off, 1, "Prefix length: %d", prefix_length); } break; } return 4 + optlen; } static void dissect_dhcpv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean downstream) { proto_tree *bp_tree = NULL; proto_item *ti; guint8 msgtype; guint32 xid; int off, eoff; gboolean at_end; downstream = 0; /* feature reserved */ if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "DHCPv6"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); msgtype = tvb_get_guint8(tvb, 0); /* XXX relay agent messages have to be decoded differently */ xid = tvb_get_ntohl(tvb, 0) & 0x00ffffff; if (check_col(pinfo->cinfo, COL_INFO)) { col_set_str(pinfo->cinfo, COL_INFO, val_to_str(msgtype, msgtype_vals, "Message Type %u")); } if (tree) { ti = proto_tree_add_item(tree, proto_dhcpv6, tvb, 0, -1, FALSE); bp_tree = proto_item_add_subtree(ti, ett_dhcpv6); proto_tree_add_uint(bp_tree, hf_dhcpv6_msgtype, tvb, 0, 1, msgtype); proto_tree_add_text(bp_tree, tvb, 1, 3, "Transaction-ID: 0x%08x", xid); #if 0 tvb_memcpy(tvb, (guint8 *)&in6, 4, sizeof(in6)); proto_tree_add_text(bp_tree, tvb, 4, sizeof(in6), "Server address: %s", ip6_to_str(&in6)); #endif } off = 4; eoff = tvb_reported_length(tvb); at_end = FALSE; while (off < eoff && !at_end) off += dhcpv6_option(tvb, bp_tree, off, eoff, &at_end); } static void dissect_dhcpv6_downstream(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { dissect_dhcpv6(tvb, pinfo, tree, TRUE); } static void dissect_dhcpv6_upstream(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { dissect_dhcpv6(tvb, pinfo, tree, FALSE); } void proto_register_dhcpv6(void) { static hf_register_info hf[] = { { &hf_dhcpv6_msgtype, { "Message type", "dhcpv6.msgtype", FT_UINT8, BASE_DEC, VALS(msgtype_vals), 0x0, "", HFILL }}, }; static gint *ett[] = { &ett_dhcpv6, &ett_dhcpv6_option, }; proto_dhcpv6 = proto_register_protocol("DHCPv6", "DHCPv6", "dhcpv6"); proto_register_field_array(proto_dhcpv6, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); } void proto_reg_handoff_dhcpv6(void) { dissector_handle_t dhcpv6_handle; dhcpv6_handle = create_dissector_handle(dissect_dhcpv6_downstream, proto_dhcpv6); dissector_add("udp.port", UDP_PORT_DHCPV6_DOWNSTREAM, dhcpv6_handle); dhcpv6_handle = create_dissector_handle(dissect_dhcpv6_upstream, proto_dhcpv6); dissector_add("udp.port", UDP_PORT_DHCPV6_UPSTREAM, dhcpv6_handle); }