diff options
author | Jun-ichiro itojun Hagino <itojun@itojun.org> | 2002-01-09 02:51:46 +0000 |
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committer | Jun-ichiro itojun Hagino <itojun@itojun.org> | 2002-01-09 02:51:46 +0000 |
commit | 7cfaf110e6ec7903ecbd9d0d35c161e2f37ffce8 (patch) | |
tree | 15afd9c2abc6c361347f97132c500fbb407d3d5d /packet-dhcpv6.c | |
parent | 5e7698f3224a44369e62e85c9448447c75f278ab (diff) |
DHCPv6 dissector, based on draft-ietf-dhc-dhcpv6-22.txt.
note that protocol constants are subject to change.
(packet format is also subject to change. but 22 draft should go
to wg last call very soon, and I really hope it to be the final one...)
svn path=/trunk/; revision=4504
Diffstat (limited to 'packet-dhcpv6.c')
-rw-r--r-- | packet-dhcpv6.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/packet-dhcpv6.c b/packet-dhcpv6.c new file mode 100644 index 0000000000..cbae66cde4 --- /dev/null +++ b/packet-dhcpv6.c @@ -0,0 +1,268 @@ +/* packet-dhpcv6.c + * Routines for DHCPv6 packet disassembly + * Jun-ichiro itojun Hagino <itojun@iijlab.net> + * + * $Id: packet-dhcpv6.c,v 1.1 2002/01/09 02:51:46 itojun Exp $ + * + * The information used comes from: + * draft-ietf-dhc-dhcpv6-22.txt + * Note that protocol constants are still subject to change, based on IANA + * assignment decisions. + * + * Ethereal - Network traffic analyzer + * By Gerald Combs <gerald@ethereal.com> + * 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 <sys/types.h> +#endif + +#include <string.h> +#include <glib.h> +#include "int-64bit.h" +#include "packet.h" +#include "ipv6-utils.h" + +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 + +static const value_string msgtype_vals[] = { + { 7, "Reply" }, + { 11, "Information request" }, + { 0, NULL } +}; + +static const value_string opttype_vals[] = { + { 1, "DUID" }, + { 11, "DNS servers address" }, + { 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 1: /* DUID */ + 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: %u", duidtype); + switch (duidtype) { + case 1: + 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, 4, + "Time: %u", tvb_get_ntohl(tvb, off + 6)); + proto_tree_add_text(subtree, tvb, off + 6, 2, + "Hardware type: %u", + tvb_get_ntohs(tvb, off + 6)); + if (optlen > 8) { + proto_tree_add_text(subtree, tvb, off + 8, + optlen - 8, "Link-layer address"); + } + break; + case 2: + if (optlen < 10) { + proto_tree_add_text(subtree, tvb, off, + optlen, "DUID: malformed option"); + break; + } + proto_tree_add_text(subtree, tvb, off + 2, 8, "VUID"); + if (optlen > 10) { + proto_tree_add_text(subtree, tvb, off + 10, + optlen - 10, "Domain name"); + } + break; + case 3: + 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 + 10)); + if (optlen > 4) { + proto_tree_add_text(subtree, tvb, off + 4, + optlen - 4, "Link-layer address"); + } + break; + } + break; + case 11: /* DNS servers address */ + 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; + } + + return 4 + optlen; +} + +static void +dissect_dhcpv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int downstream) +{ + proto_tree *bp_tree = NULL; + proto_item *ti; + guint8 msgtype; + guint32 xid; + struct e_in6_addr in6; + int off, eoff; + gboolean at_end; + + 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, + downstream ? "DHCPv6 reply" : "DHCPv6 request"); + } + + if (tree) { + ti = proto_tree_add_item(tree, proto_dhcpv6, tvb, 0, + tvb_length(tvb), 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, "XID: 0x%08x", xid); + 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)); + } + + off = 20; + 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) +{ + return dissect_dhcpv6(tvb, pinfo, tree, 1); +} + +static void +dissect_dhcpv6_upstream(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + return dissect_dhcpv6(tvb, pinfo, tree, 0); +} + + +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); +} |