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authorGuy Harris <guy@alum.mit.edu>2001-07-10 20:55:54 +0000
committerGuy Harris <guy@alum.mit.edu>2001-07-10 20:55:54 +0000
commit24ec54336f358bc7453d84af1b42fdfe5ac539a3 (patch)
tree9b3c10bd1dd62bc6b1de0ece1294750b434c9258 /packet-igmp.c
parent188717373e36d79070083f74ef53a140e3a365b7 (diff)
IGMP fixes and multicast traceroute support, from Heikki Vatiainen.
Assorted other fixes. svn path=/trunk/; revision=3677
Diffstat (limited to 'packet-igmp.c')
-rw-r--r--packet-igmp.c337
1 files changed, 300 insertions, 37 deletions
diff --git a/packet-igmp.c b/packet-igmp.c
index 50612c07e4..8c1eaf30e7 100644
--- a/packet-igmp.c
+++ b/packet-igmp.c
@@ -1,7 +1,7 @@
/* packet-igmp.c 2001 Ronnie Sahlberg <rsahlber@bigpond.net.au>
* Routines for IGMP packet disassembly
*
- * $Id: packet-igmp.c,v 1.8 2001/07/02 09:23:02 guy Exp $
+ * $Id: packet-igmp.c,v 1.9 2001/07/10 20:55:54 guy Exp $
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@ethereal.com>
@@ -54,6 +54,15 @@
* Differs in second byte of protocol. Always 0 in V1
+
+ Multicast traceroute was taken from
+ draft-ietf-idmr-traceroute-ipm-07.txt
+
+ Size in bytes for each packet
+ type draft-ietf-idmr-traceroute-ipm-07.ps
+ 0x1e 24 + n*32
+ 0x1f 24 + n*32 (n == 0 for Query)
+
x DVMRP Protocol see packet-dvmrp.c
DVMRP is defined in the following RFCs
@@ -122,11 +131,31 @@ static int hf_record_type = -1;
static int hf_aux_data_len = -1;
static int hf_maddr = -1;
static int hf_aux_data = -1;
+static int hf_mtrace_max_hops = -1;
+static int hf_mtrace_saddr = -1;
+static int hf_mtrace_raddr = -1;
+static int hf_mtrace_rspaddr = -1;
+static int hf_mtrace_resp_ttl = -1;
+static int hf_mtrace_q_id = -1;
+static int hf_mtrace_q_arrival = -1;
+static int hf_mtrace_q_inaddr = -1;
+static int hf_mtrace_q_outaddr = -1;
+static int hf_mtrace_q_prevrtr = -1;
+static int hf_mtrace_q_inpkt = -1;
+static int hf_mtrace_q_outpkt = -1;
+static int hf_mtrace_q_total = -1;
+static int hf_mtrace_q_rtg_proto = -1;
+static int hf_mtrace_q_fwd_ttl = -1;
+static int hf_mtrace_q_mbz = -1;
+static int hf_mtrace_q_s = -1;
+static int hf_mtrace_q_src_mask = -1;
+static int hf_mtrace_q_fwd_code = -1;
static int ett_igmp = -1;
static int ett_group_record = -1;
static int ett_sqrv_bits = -1;
static int ett_max_resp = -1;
+static int ett_mtrace_block = -1;
#define MC_ALL_ROUTERS 0xe0000002
#define MC_ALL_IGMPV3_ROUTERS 0xe0000016
@@ -146,14 +175,19 @@ static int ett_max_resp = -1;
#define IGMP_V1_PIM_ROUTING_MESSAGE 0x14
#define IGMP_V2_MEMBERSHIP_REPORT 0x16
#define IGMP_V2_LEAVE_GROUP 0x17
-#define IGMP_V1_TRACEROUTE_RESPONSE 0x1e /* XXX */
-#define IGMP_V1_TRACEROUTE_MESSAGE 0x1f /* XXX */
+#define IGMP_V1_TRACEROUTE_RESPONSE 0x1e
+#define IGMP_V1_TRACEROUTE_MESSAGE 0x1f
#define IGMP_V3_MEMBERSHIP_REPORT 0x22
#define IGMP_TYPE_0x23 0x23
#define IGMP_TYPE_0x24 0x24
#define IGMP_TYPE_0x25 0x25
#define IGMP_TYPE_0x26 0x26
+#define IGMP_TRACEROUTE_HDR_LEN 24
+#define IGMP_TRACEROUTE_RSP_LEN 32
+#define IGMP_TRACEROUTE_RESPONSE 0x1e
+#define IGMP_TRACEROUTE_QUERY_REQ 0x1f
+
static const value_string commands[] = {
{IGMP_V0_CREATE_GROUP_REQUEST, "Create Group Request" },
{IGMP_V0_CREATE_GROUP_REPLY, "Create Group Reply" },
@@ -169,8 +203,6 @@ static const value_string commands[] = {
{IGMP_V1_PIM_ROUTING_MESSAGE, "PIM Routing Message" },
{IGMP_V2_MEMBERSHIP_REPORT, "Membership Report" },
{IGMP_V2_LEAVE_GROUP, "Leave Group" },
- {IGMP_V1_TRACEROUTE_RESPONSE, "Traceroute Response" },
- {IGMP_V1_TRACEROUTE_MESSAGE, "Traceroute Message" },
{IGMP_V3_MEMBERSHIP_REPORT, "Membership Report" },
{0, NULL}
};
@@ -227,6 +259,40 @@ static const value_string vs_record_type[] = {
{ 0, NULL}
};
+static const value_string mtrace_rtg_vals[] = {
+ {1, "DVMRP" },
+ {2, "MOSPF" },
+ {3, "PIM" },
+ {4, "CBT" },
+ {5, "PIM using special routing table" },
+ {6, "PIM using a static route" },
+ {7, "DVMRP using a static route" },
+ {8, "PIM using MBGP (aka BGP4+) route" },
+ {9, "CBT using special routing table" },
+ {10, "CBT using a static route" },
+ {11, "PIM using state created by Assert processing" },
+ {0, NULL}
+};
+
+static const value_string mtrace_fwd_code_vals[] = {
+ {0x00, "NO_ERROR" },
+ {0x01, "WRONG_IF" },
+ {0x02, "PRUNE_SENT" },
+ {0x03, "PRUNE_RCVD" },
+ {0x04, "SCOPED" },
+ {0x05, "NO_ROUTE" },
+ {0x06, "WRONG_LAST_HOP" },
+ {0x07, "NOT_FORWARDING" },
+ {0x08, "REACHED_RP" },
+ {0x09, "RPF_IF" },
+ {0x0A, "NO_MULTICAST" },
+ {0x0B, "INFO_HIDDEN" },
+ {0x81, "NO_SPACE" },
+ {0x82, "OLD_ROUTER" },
+ {0x83, "ADMIN_PROHIB" },
+ {0, NULL}
+};
+
#define PRINT_IGMP_VERSION(version) \
if (check_col(pinfo->fd, COL_INFO)) { \
col_add_fstr(pinfo->fd, COL_INFO, \
@@ -355,7 +421,7 @@ dissect_v3_group_record(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tr
guint16 num;
guint32 ip;
- ip = tvb_get_letohl(tvb, offset+4);
+ tvb_memcpy(tvb, (guint8 *)&ip, offset+4, 4);
item = proto_tree_add_text(parent_tree, tvb, offset, 0,
"Group Record : %s %s",
ip_to_str((gchar*)&ip),
@@ -364,7 +430,7 @@ dissect_v3_group_record(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tr
tree = proto_item_add_subtree(item, ett_group_record);
/* record type */
- proto_tree_add_uint(tree, hf_record_type, tvb, offset, 1, tvb_get_guint8(tvb, offset));
+ proto_tree_add_item(tree, hf_record_type, tvb, offset, 1, FALSE);
offset += 1;
/* aux data len */
@@ -378,20 +444,19 @@ dissect_v3_group_record(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tr
offset += 2;
/* multicast address */
- proto_tree_add_ipv4(tree, hf_maddr, tvb,
- offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
offset += 4;
/* source addresses */
while(num--){
- proto_tree_add_ipv4(tree, hf_saddr, tvb,
- offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_saddr, tvb, offset, 4, FALSE);
offset += 4;
}
/* aux data */
if(adl){
- proto_tree_add_bytes(tree, hf_aux_data, tvb, offset, adl*4, tvb_get_ptr(tvb, offset, adl*4));
+ proto_tree_add_item(tree, hf_aux_data, tvb, offset, adl*4,
+ FALSE);
offset += adl*4;
}
@@ -445,14 +510,14 @@ dissect_igmp_v3_query(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int t
offset += 2;
/* group address */
- proto_tree_add_ipv4(tree, hf_maddr, tvb, offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
offset +=4;
/* bitmask for S and QRV */
offset = dissect_v3_sqrv_bits(tvb, pinfo, tree, offset);
/* qqic */
- proto_tree_add_uint(tree, hf_qqic, tvb, offset, 1, tvb_get_guint8(tvb, offset));
+ proto_tree_add_item(tree, hf_qqic, tvb, offset, 1, FALSE);
offset += 1;
/*number of sources*/
@@ -460,8 +525,7 @@ dissect_igmp_v3_query(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int t
offset += 2;
while(num--){
- proto_tree_add_ipv4(tree, hf_saddr, tvb,
- offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_saddr, tvb, offset, 4, FALSE);
offset += 4;
}
@@ -487,7 +551,7 @@ dissect_igmp_v2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int type, i
offset += 2;
/* group address */
- proto_tree_add_ipv4(tree, hf_maddr, tvb, offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
offset +=4;
return offset;
@@ -507,7 +571,7 @@ dissect_igmp_v1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int type, i
offset += 2;
/* group address */
- proto_tree_add_ipv4(tree, hf_maddr, tvb, offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
offset +=4;
return offset;
@@ -539,20 +603,155 @@ dissect_igmp_v0(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int type, i
offset += 2;
/* identifier */
- proto_tree_add_uint(tree, hf_identifier, tvb, offset, 4, tvb_get_ntohl(tvb, offset));
+ proto_tree_add_item(tree, hf_identifier, tvb, offset, 4, FALSE);
offset += 4;
/* group address */
- proto_tree_add_ipv4(tree, hf_maddr, tvb, offset, 4, tvb_get_letohl(tvb, offset));
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
offset +=4;
/* access key */
- proto_tree_add_bytes(tree, hf_access_key, tvb, offset, 8, tvb_get_ptr(tvb, offset, 8));
+ proto_tree_add_item(tree, hf_access_key, tvb, offset, 8, FALSE);
offset +=8;
return offset;
}
+/* dissector for multicast traceroute, rfc???? */
+static int
+dissect_igmp_mtrace(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int type, int offset)
+{
+ char *typestr, *blocks = NULL;
+ char buf[20];
+
+ /* All multicast traceroute packets (Query, Request and
+ * Response) have the same fixed header. Request and Response
+ * have one or more response data blocks following this fixed
+ * header. Since Query and Request share the same IGMP type,
+ * the method to differentiate between them is to check the
+ * IGMP packet length. Queries are only
+ * IGMP_TRACEROUTE_HDR_LEN bytes long.
+ */
+ if (type == IGMP_TRACEROUTE_RESPONSE) {
+ int i = (tvb_reported_length_remaining(tvb, offset) - IGMP_TRACEROUTE_HDR_LEN) / IGMP_TRACEROUTE_RSP_LEN;
+ snprintf(buf, sizeof buf, ", %d block%s", i, plurality(i, "", "s"));
+ typestr = "Traceroute Response";
+ blocks = buf;
+ } else if (tvb_length_remaining(tvb, offset) == IGMP_TRACEROUTE_HDR_LEN)
+ typestr = "Traceroute Query";
+ else
+ typestr = "Traceroute Request";
+
+ if (check_col(pinfo->fd, COL_INFO)) {
+ col_set_str(pinfo->fd, COL_INFO, typestr);
+ if (blocks) col_append_str(pinfo->fd, COL_INFO, blocks);
+ }
+
+ /* First add hidden for filtering, then add text for display purposes */
+ proto_tree_add_uint_hidden(tree, hf_type, tvb, offset, 1, type);
+ proto_tree_add_text(tree, tvb, offset, 1, "Type: %s (0x%x)", typestr, type);
+ offset += 1;
+
+ /* maximum number of hops that the requester wants to trace */
+ proto_tree_add_item(tree, hf_mtrace_max_hops, tvb, offset, 1, FALSE);
+ offset += 1;
+
+ /* - 2 since the checksum covers the whole IGMP packet (the entire IP payload) */
+ igmp_checksum(tree, tvb, tvb_length_remaining(tvb, offset - 2));
+ offset += 2;
+
+ /* group address to be traced */
+ proto_tree_add_item(tree, hf_maddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* address of multicast source for the path being traced */
+ proto_tree_add_item(tree, hf_mtrace_saddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* address of multicast receiver for the path being traced */
+ proto_tree_add_item(tree, hf_mtrace_raddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* address where the completed traceroute response packet gets sent */
+ proto_tree_add_item(tree, hf_mtrace_rspaddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* for multicasted responses, TTL at which to multicast the response */
+ proto_tree_add_item(tree, hf_mtrace_resp_ttl, tvb, offset, 1, FALSE);
+ offset += 1;
+
+ /* unique identifier for this traceroute request (for e.g. duplicate/delay detection) */
+ proto_tree_add_item(tree, hf_mtrace_q_id, tvb, offset, 3, FALSE);
+ offset += 3;
+
+ /* If this was Query, we only had the fixed header */
+ if (tvb_reported_length_remaining(tvb, offset) == 0)
+ return offset;
+
+ /* Loop through the response data blocks */
+ while (tvb_reported_length_remaining(tvb, offset) >= IGMP_TRACEROUTE_RSP_LEN) {
+ proto_item *bi;
+ proto_tree *block_tree;
+
+ bi = proto_tree_add_text(tree, tvb, offset, IGMP_TRACEROUTE_RSP_LEN,
+ "Response data block: %s -> %s, Proto: %s, Forwarding Code: %s",
+ ip_to_str(tvb_get_ptr(tvb, offset + 4, 4)),
+ ip_to_str(tvb_get_ptr(tvb, offset + 8, 4)),
+ val_to_str(tvb_get_guint8(tvb, offset + 28), mtrace_rtg_vals, "Unknown"),
+ val_to_str(tvb_get_guint8(tvb, offset + 31), mtrace_fwd_code_vals, "Unknown"));
+ block_tree = proto_item_add_subtree(bi, ett_mtrace_block);
+
+ /* Query Arrival Time */
+ proto_tree_add_item(block_tree, hf_mtrace_q_arrival, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Incoming Interface Address */
+ proto_tree_add_item(block_tree, hf_mtrace_q_inaddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Outgoing Interface Address */
+ proto_tree_add_item(block_tree, hf_mtrace_q_outaddr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Previous-Hop Router Address */
+ proto_tree_add_item(block_tree, hf_mtrace_q_prevrtr, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Input packet count on incoming interface */
+ proto_tree_add_item(block_tree, hf_mtrace_q_inpkt, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Output packet count on outgoing interface */
+ proto_tree_add_item(block_tree, hf_mtrace_q_outpkt, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Total number of packets for this source-group pair */
+ proto_tree_add_item(block_tree, hf_mtrace_q_total, tvb, offset, 4, FALSE);
+ offset += 4;
+
+ /* Routing protocol in use between this and previous-hop router */
+ proto_tree_add_item(block_tree, hf_mtrace_q_rtg_proto, tvb, offset, 1, FALSE);
+ offset += 1;
+
+ /* TTL that a packet is required to be forwarded */
+ proto_tree_add_item(block_tree, hf_mtrace_q_fwd_ttl, tvb, offset, 1, FALSE);
+ offset += 1;
+
+ /* Must be zeroed and ignored bit, S bit and src network mask length */
+ proto_tree_add_item(block_tree, hf_mtrace_q_mbz, tvb, offset, 1, FALSE);
+ proto_tree_add_item(block_tree, hf_mtrace_q_s, tvb, offset, 1, FALSE);
+ proto_tree_add_item(block_tree, hf_mtrace_q_src_mask, tvb, offset, 1, FALSE);
+ offset += 1;
+
+ /* Forwarding information/error code */
+ proto_tree_add_item(block_tree, hf_mtrace_q_fwd_code, tvb, offset, 1, FALSE);
+ offset += 1;
+ }
+
+
+ return offset;
+}
+
static void
dissect_igmp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree)
{
@@ -621,22 +820,9 @@ dissect_igmp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree)
offset = dissect_igmp_v2(tvb, pinfo, tree, type, offset);
break;
- case IGMP_V1_TRACEROUTE_RESPONSE:
- /* XXX - V1 or V2? */
- offset = dissect_igmp_v1(tvb, pinfo, tree, type, offset);
- /*
- * XXX - dissect the rest as traceroute response; see the
- * tcpdump IGMP dissector.
- */
- break;
-
- case IGMP_V1_TRACEROUTE_MESSAGE:
- /* XXX - V1 or V2? */
- offset = dissect_igmp_v1(tvb, pinfo, tree, type, offset);
- /*
- * XXX - dissect the rest as traceroute message; see the
- * tcpdump IGMP dissector.
- */
+ case IGMP_TRACEROUTE_RESPONSE:
+ case IGMP_TRACEROUTE_QUERY_REQ:
+ offset = dissect_igmp_mtrace(tvb, pinfo, tree, type, offset);
break;
case IGMP_V3_MEMBERSHIP_REPORT:
@@ -782,12 +968,89 @@ proto_register_igmp(void)
{ "Mantissa", "igmp.max_resp.mant", FT_UINT8, BASE_HEX,
NULL, IGMP_MAX_RESP_MANT, "Maxmimum Response Time, Mantissa", HFILL }},
+ { &hf_mtrace_max_hops,
+ { "# hops", "igmp.mtrace.max_hops", FT_UINT8, BASE_DEC,
+ NULL, 0, "Maxmimum Number of Hops to Trace", HFILL }},
+
+ { &hf_mtrace_saddr,
+ { "Source Address", "igmp.mtrace.saddr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Multicast Source for the Path Being Traced", HFILL }},
+
+ { &hf_mtrace_raddr,
+ { "Receiver Address", "igmp.mtrace.raddr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Multicast Receiver for the Path Being Traced", HFILL }},
+
+ { &hf_mtrace_rspaddr,
+ { "Response Address", "igmp.mtrace.rspaddr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Destination of Completed Traceroute Response", HFILL }},
+
+ { &hf_mtrace_resp_ttl,
+ { "Response TTL", "igmp.mtrace.resp_ttl", FT_UINT8, BASE_DEC,
+ NULL, 0, "TTL for Multicasted Responses", HFILL }},
+
+ { &hf_mtrace_q_id,
+ { "Query ID", "igmp.mtrace.q_id", FT_UINT24, BASE_DEC,
+ NULL, 0, "Identifier for this Traceroute Request", HFILL }},
+
+ { &hf_mtrace_q_arrival,
+ { "Query Arrival", "igmp.mtrace.q_arrival", FT_UINT32, BASE_DEC,
+ NULL, 0, "Query Arrival Time", HFILL }},
+
+ { &hf_mtrace_q_inaddr,
+ { "In itf addr", "igmp.mtrace.q_inaddr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Incoming Interface Address", HFILL }},
+
+ { &hf_mtrace_q_outaddr,
+ { "Out itf addr", "igmp.mtrace.q_outaddr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Outgoing Interface Address", HFILL }},
+
+ { &hf_mtrace_q_prevrtr,
+ { "Previous rtr addr", "igmp.mtrace.q_prevrtr", FT_IPv4, BASE_NONE,
+ NULL, 0, "Previous-Hop Router Address", HFILL }},
+
+ { &hf_mtrace_q_inpkt,
+ { "In pkts", "igmp.mtrace.q_inpkt", FT_UINT32, BASE_DEC,
+ NULL, 0, "Input packet count on incoming interface", HFILL }},
+
+ { &hf_mtrace_q_outpkt,
+ { "Out pkts", "igmp.mtrace.q_outpkt", FT_UINT32, BASE_DEC,
+ NULL, 0, "Output packet count on outgoing interface", HFILL }},
+
+ { &hf_mtrace_q_total,
+ { "S,G pkt count", "igmp.mtrace.q_total", FT_UINT32, BASE_DEC,
+ NULL, 0, "Total number of packets for this source-group pair", HFILL }},
+
+ { &hf_mtrace_q_rtg_proto,
+ { "Rtg Protocol", "igmp.mtrace.q_rtg_proto", FT_UINT8, BASE_DEC,
+ VALS(&mtrace_rtg_vals), 0, "Routing protocol between this and previous hop rtr", HFILL }},
+
+ { &hf_mtrace_q_fwd_ttl,
+ { "FwdTTL", "igmp.mtrace.q_fwd_ttl", FT_UINT8, BASE_DEC,
+ NULL, 0, "TTL required for forwarding", HFILL }},
+
+ { &hf_mtrace_q_mbz,
+ { "MBZ", "igmp.mtrace.q_mbz", FT_UINT8, BASE_HEX,
+ NULL, 0x80, "Must be zeroed on transmission and ignored on reception", HFILL }},
+
+ { &hf_mtrace_q_s,
+ { "S", "igmp.mtrace.q_s", FT_UINT8, BASE_HEX,
+ NULL, 0x40, "Set if S,G packet count is for source network", HFILL }},
+
+ { &hf_mtrace_q_src_mask,
+ { "Src Mask", "igmp.mtrace.q_src_mask", FT_UINT8, BASE_HEX,
+ NULL, 0x3F, "Source mask length. 63 when forwarding on group state", HFILL }},
+
+ { &hf_mtrace_q_fwd_code,
+ { "Forwarding Code", "igmp.mtrace.q_fwd_code", FT_UINT8, BASE_HEX,
+ VALS(&mtrace_fwd_code_vals), 0, "Forwarding information/error code", HFILL }},
+
};
static gint *ett[] = {
&ett_igmp,
&ett_group_record,
&ett_sqrv_bits,
&ett_max_resp,
+ &ett_mtrace_block,
};
proto_igmp = proto_register_protocol("Internet Group Management Protocol",