Create real subdissectors to the IGMP protocol.

Change-Id: I79ee9413b87722bfe4782342737cff03cfc34495
Reviewed-on: https://code.wireshark.org/review/5179
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 27 insertions, 19 deletions

diff --git a/epan/dissectors/packet-mrdisc.c b/epan/dissectors/packet-mrdisc.c
index 4b0fbf9c27..71db82feb2 100644
--- a/epan/dissectors/packet-mrdisc.c
+++ b/epan/dissectors/packet-mrdisc.c
@@ -42,7 +42,6 @@
 #include <epan/exceptions.h>
 
 #include "packet-igmp.h"
-#include "packet-mrdisc.h"
 
 void proto_register_mrdisc(void);
 
@@ -62,6 +61,8 @@ static int hf_option_bytes = -1;
 static int ett_mrdisc = -1;
 static int ett_options = -1;
 
+#define MC_ALL_ROUTERS		0xe0000002
+
 #define MRDISC_MRA	0x24
 #define MRDISC_MRS	0x25
 #define MRDISC_MRT	0x26
@@ -183,26 +184,23 @@ dissect_mrdisc_mrst(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree,
 
 /* This function is only called from the IGMP dissector */
 int
-dissect_mrdisc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, int offset)
+dissect_mrdisc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* data _U_)
 {
 	proto_tree *tree;
 	proto_item *item;
 	guint8 type;
+	int offset = 0;
+	guint32 dst = g_htonl(MC_ALL_ROUTERS);
 
-	if (!proto_is_protocol_enabled(find_protocol_by_id(proto_mrdisc))) {
-		/* we are not enabled, skip entire packet to be nice
-		   to the igmp layer. (so clicking on IGMP will display the data)
-		 */
-		return offset+tvb_length_remaining(tvb, offset);
-	}
-
-	item = proto_tree_add_item(parent_tree, proto_mrdisc, tvb, offset, 0, ENC_NA);
-	tree = proto_item_add_subtree(item, ett_mrdisc);
-
+    /* Shouldn't be destined for us */
+	if (memcmp(pinfo->dst.data, &dst, 4))
+        return 0;
 
 	col_set_str(pinfo->cinfo, COL_PROTOCOL, "MRDISC");
 	col_clear(pinfo->cinfo, COL_INFO);
 
+	item = proto_tree_add_item(parent_tree, proto_mrdisc, tvb, offset, 0, ENC_NA);
+	tree = proto_item_add_subtree(item, ett_mrdisc);
 
 	type = tvb_get_guint8(tvb, offset);
 	col_add_str(pinfo->cinfo, COL_INFO,
@@ -245,11 +243,11 @@ proto_register_mrdisc(void)
 
 		{ &hf_advint,
 			{ "Advertising Interval", "mrdisc.adv_int", FT_UINT8, BASE_DEC,
-		  	  NULL, 0, "MRDISC Advertising Interval in seconds", HFILL }},
+			  NULL, 0, "MRDISC Advertising Interval in seconds", HFILL }},
 
 		{ &hf_numopts,
 			{ "Number Of Options", "mrdisc.num_opts", FT_UINT16, BASE_DEC,
-		  	  NULL, 0, "MRDISC Number Of Options", HFILL }},
+			  NULL, 0, "MRDISC Number Of Options", HFILL }},
 
 		{ &hf_options,
 			{ "Options", "mrdisc.options", FT_NONE, BASE_NONE,
@@ -265,15 +263,15 @@ proto_register_mrdisc(void)
 
 		{ &hf_qi,
 			{ "Query Interval", "mrdisc.query_int", FT_UINT16, BASE_DEC,
-		  	  NULL, 0, "MRDISC Query Interval", HFILL }},
+			  NULL, 0, "MRDISC Query Interval", HFILL }},
 
 		{ &hf_rv,
 			{ "Robustness Variable", "mrdisc.rob_var", FT_UINT16, BASE_DEC,
-		  	  NULL, 0, "MRDISC Robustness Variable", HFILL }},
+			  NULL, 0, "MRDISC Robustness Variable", HFILL }},
 
 		{ &hf_option_bytes,
 			{ "Data", "mrdisc.option_data", FT_BYTES, BASE_NONE,
-		  	  NULL, 0, "MRDISC Unknown Option Data", HFILL }},
+			  NULL, 0, "MRDISC Unknown Option Data", HFILL }},
 
 	};
 	static gint *ett[] = {
@@ -281,12 +279,22 @@ proto_register_mrdisc(void)
 		&ett_options,
 	};
 
-	proto_mrdisc = proto_register_protocol("Multicast Router DISCovery protocol",
-	    "MRDISC", "mrdisc");
+	proto_mrdisc = proto_register_protocol("Multicast Router DISCovery protocol", "MRDISC", "mrdisc");
 	proto_register_field_array(proto_mrdisc, hf, array_length(hf));
 	proto_register_subtree_array(ett, array_length(ett));
 }
 
+void
+proto_reg_handoff_mrdisc(void)
+{
+	dissector_handle_t mrdisc_handle;
+
+	mrdisc_handle = new_create_dissector_handle(dissect_mrdisc, proto_mrdisc);
+	dissector_add_uint("igmp.type", IGMP_TYPE_0x24, mrdisc_handle);
+	dissector_add_uint("igmp.type", IGMP_TYPE_0x25, mrdisc_handle);
+	dissector_add_uint("igmp.type", IGMP_TYPE_0x26, mrdisc_handle);
+}
+
 /*
  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
  *