2 * Routines for the Cisco Auto-RP protocol
3 * ftp://ftpeng.cisco.com/ftp/ipmulticast/specs/pim-autorp-spec01.txt
5 * Heikki Vatiainen <hessu@cs.tut.fi>
9 * Wireshark - Network traffic analyzer
10 * By Gerald Combs <gerald@wireshark.org>
11 * Copyright 1998 Gerald Combs
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
34 #include <epan/packet.h>
35 #include <epan/addr_resolv.h>
37 static gint proto_auto_rp = -1;
38 static gint ett_auto_rp = -1;
39 static gint ett_auto_rp_ver_type = -1;
40 static gint ett_auto_rp_map = -1;
41 static gint ett_auto_rp_group = -1;
43 static gint hf_auto_rp_version = -1;
44 static gint hf_auto_rp_type = -1;
45 static gint hf_auto_rp_count = -1;
46 static gint hf_auto_rp_holdtime = -1;
47 static gint hf_auto_rp_pim_ver = -1;
48 static gint hf_auto_rp_rp_addr = -1;
49 static gint hf_auto_rp_prefix_sgn = -1;
50 static gint hf_auto_rp_mask_len = -1;
51 static gint hf_auto_rp_group_prefix = -1;
53 #define UDP_PORT_PIM_RP_DISC 496
55 struct auto_rp_fixed_hdr {
56 #define AUTO_RP_VERSION_MASK 0xf0
57 #define AUTO_RP_TYPE_MASK 0x0f
58 guint8 ver_type; /* pim-autorp-spec01.txt defines version 1+ */
59 guint8 rp_count; /* Number of struct auto_rp_maps that follow the this header */
60 guint16 holdtime; /* Time in seconds this announcement is valid. 0 equals forever */
64 struct auto_rp_map_hdr {
65 guint32 rp_address; /* The unicast IPv4 address of this RP */
66 #define AUTO_RP_PIM_VER_MASK 0x03
67 guint8 pim_version; /* RP's highest PIM version. 2-bit field */
68 guint8 group_count; /* Number of encoded group addresses that follow this header */
71 struct auto_rp_enc_grp_hdr { /* Encoded group address */
72 #define AUTO_RP_SIGN_MASK 0x01
73 guint8 prefix_sgn; /* 0 positive, 1 negative group prefix */
74 guint8 mask_len; /* Length of group prefix */
75 guint32 addr; /* Group prefix */
78 #define AUTO_RP_VER_1PLUS 1
79 static const value_string auto_rp_ver_vals[] = {
80 {AUTO_RP_VER_1PLUS, "1 or 1+"},
84 #define AUTO_RP_TYPE_ANNOUNCEMENT 1
85 #define AUTO_RP_TYPE_MAPPING 2
86 static const value_string auto_rp_type_vals[] = {
87 {AUTO_RP_TYPE_ANNOUNCEMENT, "RP announcement"},
88 {AUTO_RP_TYPE_MAPPING, "RP mapping"},
92 #define AUTO_RP_PIM_VERSION_UNKNOWN 0x00
93 #define AUTO_RP_PIM_VERSION_1 0x01
94 #define AUTO_RP_PIM_VERSION_2 0x02
95 #define AUTO_RP_PIM_VERSION_DUAL 0x03
96 static const value_string auto_rp_pim_ver_vals[] = {
97 {AUTO_RP_PIM_VERSION_UNKNOWN, "Version unknown"},
98 {AUTO_RP_PIM_VERSION_1, "Version 1"},
99 {AUTO_RP_PIM_VERSION_2, "Version 2"},
100 {AUTO_RP_PIM_VERSION_DUAL, "Dual version 1 and 2"},
104 #define AUTO_RP_GROUP_MASK_SIGN_POS 0
105 #define AUTO_RP_GROUP_MASK_SIGN_NEG 1
106 static const value_string auto_rp_mask_sign_vals[] = {
107 {AUTO_RP_GROUP_MASK_SIGN_POS, "Positive group prefix"},
108 {AUTO_RP_GROUP_MASK_SIGN_NEG, "Negative group prefix"},
112 static int do_auto_rp_map(tvbuff_t *tvb, int offset, proto_tree *auto_rp_tree);
114 static void dissect_auto_rp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
116 guint8 ver_type, rp_count;
118 col_set_str(pinfo->cinfo, COL_PROTOCOL, "Auto-RP");
119 if (check_col(pinfo->cinfo, COL_INFO))
120 col_clear(pinfo->cinfo, COL_INFO);
122 ver_type = tvb_get_guint8(tvb, 0);
123 rp_count = tvb_get_guint8(tvb, 1);
124 if (check_col(pinfo->cinfo, COL_INFO))
125 col_add_fstr(pinfo->cinfo, COL_INFO, "%s (v%s) for %u RP%s",
126 val_to_str(lo_nibble(ver_type), auto_rp_type_vals, "Unknown"),
127 val_to_str(hi_nibble(ver_type), auto_rp_ver_vals, "Unknown"),
128 rp_count, plurality(rp_count, "", "s"));
132 proto_tree *auto_rp_tree, *ver_type_tree;
137 ti = proto_tree_add_item(tree, proto_auto_rp, tvb, offset, -1, FALSE);
138 auto_rp_tree = proto_item_add_subtree(ti, ett_auto_rp);
140 tv = proto_tree_add_text(auto_rp_tree, tvb, offset, 1, "Version: %s, Packet type: %s",
141 val_to_str(hi_nibble(ver_type), auto_rp_ver_vals, "Unknown"),
142 val_to_str(lo_nibble(ver_type), auto_rp_type_vals, "Unknown"));
143 ver_type_tree = proto_item_add_subtree(tv, ett_auto_rp_ver_type);
144 proto_tree_add_uint(ver_type_tree, hf_auto_rp_version, tvb, offset, 1, ver_type);
145 proto_tree_add_uint(ver_type_tree, hf_auto_rp_type, tvb, offset, 1, ver_type);
148 proto_tree_add_uint(auto_rp_tree, hf_auto_rp_count, tvb, offset, 1, rp_count);
151 holdtime = tvb_get_ntohs(tvb, offset);
152 proto_tree_add_uint_format_value(auto_rp_tree, hf_auto_rp_holdtime, tvb, offset, 2, holdtime,
153 "%u second%s", holdtime, plurality(holdtime, "", "s"));
156 proto_tree_add_text(auto_rp_tree, tvb, offset, 4, "Reserved: 0x%x", tvb_get_ntohs(tvb, offset));
159 for (i = 0; i < rp_count; i++)
160 offset = do_auto_rp_map(tvb, offset, auto_rp_tree);
162 if (tvb_offset_exists(tvb, offset))
163 proto_tree_add_text(tree, tvb, offset, -1, "Trailing junk");
169 void proto_register_auto_rp(void)
171 static hf_register_info hf[] = {
172 { &hf_auto_rp_version,
173 {"Protocol version", "auto_rp.version",
174 FT_UINT8, BASE_DEC, VALS(auto_rp_ver_vals), AUTO_RP_VERSION_MASK,
175 "Auto-RP protocol version", HFILL }},
178 {"Packet type", "auto_rp.type",
179 FT_UINT8, BASE_DEC, VALS(auto_rp_type_vals), AUTO_RP_TYPE_MASK,
180 "Auto-RP packet type", HFILL }},
183 {"RP count", "auto_rp.rp_count",
184 FT_UINT8, BASE_DEC, NULL, 0,
185 "The number of RP addresses contained in this message", HFILL }},
187 { &hf_auto_rp_holdtime,
188 {"Holdtime", "auto_rp.holdtime",
189 FT_UINT16, BASE_DEC, NULL, 0,
190 "The amount of time in seconds this announcement is valid", HFILL }},
192 { &hf_auto_rp_pim_ver,
193 {"Version", "auto_rp.pim_ver",
194 FT_UINT8, BASE_DEC, VALS(auto_rp_pim_ver_vals), AUTO_RP_PIM_VER_MASK,
195 "RP's highest PIM version", HFILL }},
197 { &hf_auto_rp_rp_addr,
198 {"RP address", "auto_rp.rp_addr",
199 FT_IPv4, BASE_NONE, NULL, 0,
200 "The unicast IP address of the RP", HFILL }},
202 { &hf_auto_rp_prefix_sgn,
203 {"Sign", "auto_rp.prefix_sign",
204 FT_UINT8, BASE_DEC, VALS(auto_rp_mask_sign_vals), AUTO_RP_SIGN_MASK,
205 "Group prefix sign", HFILL }},
207 { &hf_auto_rp_mask_len,
208 {"Mask length", "auto_rp.mask_len",
209 FT_UINT8, BASE_DEC, NULL, 0x0,
210 "Length of group prefix", HFILL }},
212 { &hf_auto_rp_group_prefix,
213 {"Prefix", "auto_rp.group_prefix",
214 FT_IPv4, BASE_NONE, NULL, 0,
215 "Group prefix", HFILL }}
218 static gint *ett[] = {
220 &ett_auto_rp_ver_type,
225 proto_auto_rp = proto_register_protocol("Cisco Auto-RP",
226 "Auto-RP", "auto_rp");
227 proto_register_field_array(proto_auto_rp, hf, array_length(hf));
228 proto_register_subtree_array(ett, array_length(ett));
234 proto_reg_handoff_auto_rp(void)
236 dissector_handle_t auto_rp_handle;
238 auto_rp_handle = create_dissector_handle(dissect_auto_rp,
240 dissector_add("udp.port", UDP_PORT_PIM_RP_DISC, auto_rp_handle);
244 * Handles one Auto-RP map entry. Returns the new offset.
246 static int do_auto_rp_map(tvbuff_t *tvb, int offset, proto_tree *auto_rp_tree)
249 proto_tree *map_tree;
251 guint32 rp_addr; /* In network byte order */
254 rp_addr = tvb_get_ipv4(tvb, offset);
255 group_count = tvb_get_guint8(tvb, offset + 5);
257 /* sizeof map header + n * sizeof encoded group addresses */
258 ti = proto_tree_add_text(auto_rp_tree, tvb, offset, 6 + group_count * 6,
259 "RP %s: %u group%s", ip_to_str((void *)&rp_addr),
260 group_count, plurality(group_count, "", "s"));
261 map_tree = proto_item_add_subtree(ti, ett_auto_rp_map);
263 proto_tree_add_ipv4(map_tree, hf_auto_rp_rp_addr, tvb, offset, 4, rp_addr);
265 proto_tree_add_uint(map_tree, hf_auto_rp_pim_ver, tvb, offset, 1, tvb_get_guint8(tvb, offset));
267 proto_tree_add_text(map_tree, tvb, offset, 1, "Number of groups this RP maps to: %u", group_count);
270 for (i = 0; i < group_count; i++) {
272 proto_tree *grp_tree;
273 guint8 sign, mask_len;
274 guint32 group_addr; /* In network byte order */
276 sign = tvb_get_guint8(tvb, offset);
277 mask_len = tvb_get_guint8(tvb, offset + 1);
278 group_addr = tvb_get_ipv4(tvb, offset + 2);
279 gi = proto_tree_add_text(map_tree, tvb, offset, 6, "Group %s/%u (%s)",
280 ip_to_str((void *)&group_addr), mask_len,
281 val_to_str(sign&AUTO_RP_SIGN_MASK, auto_rp_mask_sign_vals, ""));
282 grp_tree = proto_item_add_subtree(gi, ett_auto_rp_group);
284 proto_tree_add_uint(grp_tree, hf_auto_rp_prefix_sgn, tvb, offset, 1, sign);
286 proto_tree_add_uint(grp_tree, hf_auto_rp_mask_len, tvb, offset, 1, mask_len);
288 proto_tree_add_ipv4(grp_tree, hf_auto_rp_group_prefix, tvb, offset, 4, group_addr);