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Wireshark-dev: [Wireshark-dev] Patch for FMIPv6

From: Nicolas DICHTEL <nicolas.dichtel@xxxxxxxxx>
Date: Thu, 28 Sep 2006 14:41:46 +0200
Hi,

I've two patchs for FMIPv6:
  - FBU encapsulated in FNA are not correctly parsed;
  - there is an error when parsing LLA Option.

Patch is against ethereal-0.99.0, should I remake it against
the latest wireshark ?


Regards,
Nicolas
--- ethereal-0.99.0-orig/epan/dissectors/packet-mip6.c	2006-04-17 16:46:40.000000000 +0200
+++ ethereal-0.99.0/epan/dissectors/packet-mip6.c	2006-07-31 17:08:58.613037510 +0200
@@ -6,6 +6,7 @@
  * Copyright 2003 Oy L M Ericsson Ab <teemu.rinta-aho@xxxxxxxxxxx>
  *
  * FMIPv6 (RFC 4068) support added by Martin Andre <andre@xxxxxxxxxxxxxxxxxxxxx>
+ * Copyright 2006, Nicolas DICHTEL - 6WIND - <nicolas.dichtel@xxxxxxxxx>
  *
  * Modifications for NEMO packets (RFC 3963): Bruno Deniaud
  * (bdeniaud@xxxxxxxx, nono@xxxxxxxx) 12 Oct 2005
@@ -426,7 +427,6 @@ dissect_fmip6_fna(tvbuff_t *tvb, proto_t
 {
     proto_tree *data_tree = NULL;
     proto_item *ti;
-/*    tvbuff_t *ipv6_tvb;*/
 
     if (check_col(pinfo->cinfo, COL_INFO))
         col_set_str(pinfo->cinfo, COL_INFO, "Fast Neighbor Advertisement");
@@ -437,13 +437,7 @@ dissect_fmip6_fna(tvbuff_t *tvb, proto_t
         data_tree = proto_item_add_subtree(ti, ett_mip6);
     }
 
-	/* Create the tvbuffer for the next dissector */
-/*    ipv6_tvb = tvb_new_subset(tvb, FMIP6_FNA_LEN, -1, -1);*/
-
-	/* Call the IPv6 dissector */
-/*    dissect_ipv6(ipv6_tvb, pinfo, mip6_tree);*/
-
-	return MIP6_DATA_OFF+FMIP6_FNA_LEN;
+    return MIP6_DATA_OFF+FMIP6_FNA_LEN;
 }
 
 /* Functions to dissect the mobility options */
@@ -729,15 +723,29 @@ dissect_mipv6_options(tvbuff_t *tvb, int
 				} else {
 					if (dissect != NULL) {
 						/* Option has a dissector. */
-						(*dissect)(optp, tvb, offset, len + 2, pinfo, opt_tree);
+						if (opt == LLA)
+							(*dissect)(optp, tvb, offset,
+								   len + 2 + FMIP6_LLA_OPTCODE_LEN, pinfo, opt_tree);
+						else
+							(*dissect)(optp, tvb, offset, len + 2, pinfo, opt_tree);
 					} else {
 						/* Option has no data, hence no dissector. */
 						proto_tree_add_text(opt_tree, tvb, offset, len + 2, "%s", name);
 					}
 				}
-				offset += len + 2;
+				/* RFC4068 Section 6.4.4
+				 *   Length         The size of this option in octets not including the
+				 *                  Type, Length, and Option-Code fields.
+				 */
+				if (opt == LLA)
+					offset += len + 2 + FMIP6_LLA_OPTCODE_LEN;
+				else
+					offset += len + 2;
 			}
-			length -= len;
+			if (opt == LLA)
+				length -= (len + FMIP6_LLA_OPTCODE_LEN);
+			else
+				length -= len;
 		} else {
 			proto_tree_add_text(opt_tree, tvb, offset,      1, "%s", name);
 			offset += 1;
@@ -774,7 +782,7 @@ dissect_mip6(tvbuff_t *tvb, packet_info 
 {
     proto_tree *mip6_tree = NULL;
     proto_item *ti;
-    guint8     type;
+    guint8     type, pproto;
     guint      len, offset = 0, start_offset = offset;
 
     /* Make entries in Protocol column and Info column on summary display */
@@ -784,6 +792,7 @@ dissect_mip6(tvbuff_t *tvb, packet_info 
         col_clear(pinfo->cinfo, COL_INFO);
 
     len = (tvb_get_guint8(tvb, MIP6_HLEN_OFF) + 1) * 8;
+    pproto = tvb_get_guint8(tvb, MIP6_PROTO_OFF);
     if (tree) {
         ti = proto_tree_add_item(tree, proto_mip6, tvb, 0, len, FALSE);
         mip6_tree = proto_item_add_subtree(ti, ett_mip6);
@@ -875,6 +884,22 @@ dissect_mip6(tvbuff_t *tvb, packet_info 
         len -= (offset - start_offset);
         dissect_mip6_options(tvb, mip6_tree, offset, len, pinfo);
     }
+
+    if (type == FNA && pproto == IP_PROTO_IPV6) {
+	dissector_table_t ip_dissector_table;
+	tvbuff_t *ipv6_tvb;
+
+	ip_dissector_table = find_dissector_table("ip.proto");
+	ipv6_tvb = tvb_new_subset(tvb, len + 8, -1, -1);
+
+	/* Call the IPv6 dissector */
+	dissector_try_port(ip_dissector_table, pproto, ipv6_tvb, pinfo, tree);
+
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_clear(pinfo->cinfo, COL_INFO);
+	if (check_col(pinfo->cinfo, COL_INFO))
+		col_set_str(pinfo->cinfo, COL_INFO, "Fast Neighbor Advertisement[Fast Binding Update]");
+    }
 }
 
 /* Register the protocol with Ethereal */
--- ethereal-0.99.0-orig/epan/dissectors/packet-mip6.h	2006-04-17 16:46:40.000000000 +0200
+++ ethereal-0.99.0/epan/dissectors/packet-mip6.h	2006-07-31 17:09:32.100556187 +0200
@@ -7,6 +7,7 @@
  * Copyright 2003 Oy L M Ericsson Ab <teemu.rinta-aho@xxxxxxxxxxx>
  *
  * FMIPv6 support added by Martin Andre <andre@xxxxxxxxxxxxxxxxxxxxx>
+ * Copyright 2006, Nicolas DICHTEL - 6WIND - <nicolas.dichtel@xxxxxxxxx>
  *
  * Modifications for NEMO packets (RFC 3963): Bruno Deniaud
  * (bdeniaud@xxxxxxxx, nono@xxxxxxxx) 12 Oct 2005
@@ -311,7 +312,7 @@ static const value_string fmip6_lla_optc
 
 #define FMIP6_LLA_MINLEN      1
 #define FMIP6_LLA_OPTCODE_OFF 2
-#define FMIP6_LLA_LLA_OFF     4
+#define FMIP6_LLA_LLA_OFF     3
 #define FMIP6_LLA_OPTCODE_LEN 1
 
 #endif /* __PACKET_MIP6_H_DEFINED__ */