Wireshark · Ethereal-dev: [Ethereal-dev] ICMP Router Advertisements (Mobile-IP)

[David Frascone <dave@xxxxxxxxxxxx>]

I added dissection of Mobile-IP Advertisements, as defined in RFC-2002 and
RFC-3012.  The extensions 0, 16, 19, and 24 are now dissected properly.

Attached are diffs, and packet dumps containing examples of all processed
extensions.

Index: packet-ip.c
===================================================================
RCS file: /cvsroot/ethereal/packet-ip.c,v
retrieving revision 1.142
diff -r1.142 packet-ip.c
126a127,146
> /* Mobile ip */
> static int hf_icmp_mip_type = -1;
> static int hf_icmp_mip_length = -1;
> static int hf_icmp_mip_prefix_length = -1;
> static int hf_icmp_mip_seq = -1;
> static int hf_icmp_mip_life = -1;
> static int hf_icmp_mip_flags = -1;
> static int hf_icmp_mip_r = -1;
> static int hf_icmp_mip_b = -1;
> static int hf_icmp_mip_h = -1;
> static int hf_icmp_mip_f = -1;
> static int hf_icmp_mip_m = -1;
> static int hf_icmp_mip_g = -1;
> static int hf_icmp_mip_v = -1;
> static int hf_icmp_mip_res = -1;
> static int hf_icmp_mip_reserved = -1;
> static int hf_icmp_mip_coa = -1;
> static int hf_icmp_mip_challenge = -1;
> 
> 
127a148,149
> static gint ett_icmp_mip = -1;
> static gint ett_icmp_mip_flags = -1;
1121a1144,1282
> static value_string mip_extensions[] = {
>   { 0, "One byte padding extension"},               /* RFC 2002 */
>   { 16, "Mobility Agent Advertisement Extension"},  /* RFC 2002 */
>   { 19, "Prefix Lengths Extension"},                /* RFC 2002 */
>   { 24, "Challenge Extension"},                     /* RFC 3012 */
>   { 0, NULL}
> };
> 
> /*
>  * Dissect the mobile ip advertisement extensions.
>  */
> static void
> dissect_mip_extensions(tvbuff_t *tvb, size_t offset, packet_info *pinfo,
> 					   proto_tree *tree)
> {
>   guint8       type;
>   guint8       length;
>   guint8       flags;
>   proto_item   *ti;
>   proto_tree   *mip_tree=NULL;
>   proto_tree   *flags_tree=NULL;
>   gint         numCOAs;
>   gint         i;
> 
>   /* Not much to do if we're not parsing everything */
>   if (!tree) return;
>   
>   while ((tvb_length(tvb) - offset) > 0) {
> 
> 	type = tvb_get_guint8(tvb, offset + 0);
> 	if (type)
> 	  length = tvb_get_guint8(tvb, offset + 1);
> 	else
> 	  length=0;
> 
> 	ti = proto_tree_add_text(tree, tvb, offset,
> 							 type?(length + 2):1,
> 							 "Ext: %s",
> 							 val_to_str(type, mip_extensions,
> 										"Unknown ext %d"));
> 	mip_tree = proto_item_add_subtree(ti, ett_icmp_mip);
>   
> 
> 	switch (type) {
> 	case 0: /* One byte padding extension */
> 	  /* Add our fields */
> 	  /* type */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_type, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  break;
> 	case 16: /* Mobility Agent Advertisement Extension (RFC 2002)*/
> 	  /* Add our fields */
> 	  /* type */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_type, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  /* length */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_length, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  /* sequence number */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_seq, tvb, offset, 
> 						  2, FALSE);
> 	  offset+=2;
> 	  /* Registration Lifetime */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_life, tvb, offset, 
> 						  2, FALSE);
> 	  offset+=2;
> 	  /* flags */
> 	  flags = tvb_get_guint8(tvb, offset);
> 	  ti = proto_tree_add_item(mip_tree, hf_icmp_mip_flags, tvb, offset,
> 							   1, FALSE);
> 	  flags_tree = proto_item_add_subtree(ti, ett_icmp_mip_flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_r, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_b, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_h, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_f, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_m, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_g, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_v, tvb, offset, 1, flags);
> 	  proto_tree_add_boolean(flags_tree, hf_icmp_mip_res, tvb, offset, 1, flags);
> 	  offset++;
> 	  
> 	  /* Reserved */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_reserved, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  
> 	  /* COAs */
> 	  numCOAs = (length - 6) / 4;
> 	  for (i=0; i<numCOAs; i++) {
> 		proto_tree_add_item(mip_tree, hf_icmp_mip_coa, tvb, offset, 
> 							4, FALSE);
> 		offset+=4;
> 	  }
> 	  break;
> 	case 19: /* Prefix-Lengths Extension  (RFC 2002)*/
> 	  /* Add our fields */
> 	  /* type */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_type, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  /* length */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_length, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 
> 	  /* prefix lengths */
> 	  for(i=0; i<length; i++) {
> 		proto_tree_add_item(mip_tree, hf_icmp_mip_prefix_length, tvb, offset,
> 							1, FALSE);
> 		offset++;
> 	  }
> 	  break;
> 	case 24: /* Challenge Extension  (RFC 3012)*/
> 	  /* type */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_type, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  /* length */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_length, tvb, offset, 
> 						  1, FALSE);
> 	  offset++;
> 	  /* challenge */
> 	  proto_tree_add_item(mip_tree, hf_icmp_mip_challenge, tvb, offset, 
> 						  length, FALSE);
> 	  offset+=length;
> 	  
> 	  break;
> 	default:
> 	  g_warning("Unknown type(%d)!  I hope the length is right (%d)",
> 				type, length);
> 	  offset += length;
> 	  break;
> 	} /* switch type */
>   } /* end while */
>   
> } /* dissect_mip_extensions */
1217c1378,1384
<       strcpy(type_str, "Router advertisement");
---
> 	  switch(icmp_code) {
> 	  case 16: /* Mobile-Ip */
> 		strcpy(type_str, "Mobile-ip Advertisement");
> 		break;
> 	  default:
> 		strcpy(type_str, "Router advertisement");
> 	  } /* switch icmp_code */
1324,1332c1491,1499
<       case ICMP_RTRADVERT:
<         num_addrs = tvb_get_guint8(tvb, 4);
< 	proto_tree_add_text(icmp_tree, tvb, 4, 1, "Number of addresses: %u",
< 	  num_addrs);
< 	addr_entry_size = tvb_get_guint8(tvb, 5);
< 	proto_tree_add_text(icmp_tree, tvb, 5, 1, "Address entry size: %u",
< 	  addr_entry_size);
< 	proto_tree_add_text(icmp_tree, tvb, 6, 2, "Lifetime: %s",
< 	  time_secs_to_str(tvb_get_ntohs(tvb, 6)));
---
> 	case ICMP_RTRADVERT:
> 		num_addrs = tvb_get_guint8(tvb, 4);
> 		proto_tree_add_text(icmp_tree, tvb, 4, 1, "Number of addresses: %u",
> 							num_addrs);
> 		addr_entry_size = tvb_get_guint8(tvb, 5);
> 		proto_tree_add_text(icmp_tree, tvb, 5, 1, "Address entry size: %u",
> 							addr_entry_size);
> 		proto_tree_add_text(icmp_tree, tvb, 6, 2, "Lifetime: %s",
> 							time_secs_to_str(tvb_get_ntohs(tvb, 6)));
1412a1580
> 		
1414,1422c1582,1595
< 	  for (i = 0; i < num_addrs; i++) {
< 	    proto_tree_add_text(icmp_tree, tvb, 8 + (i*8), 4,
< 	      "Router address: %s",
< 	      ip_to_str(tvb_get_ptr(tvb, 8 + (i*8), 4)));
< 	    proto_tree_add_text(icmp_tree, tvb, 12 + (i*8), 4,
< 	      "Preference level: %u", tvb_get_ntohl(tvb, 12 + (i*8)));
< 	  }
< 	} else
< 	  dissect_data(tvb, 8, pinfo, icmp_tree);
---
> 		  for (i = 0; i < num_addrs; i++) {
> 			proto_tree_add_text(icmp_tree, tvb, 8 + (i*8), 4,
> 								"Router address: %s",
> 								ip_to_str(tvb_get_ptr(tvb, 8 + (i*8), 4)));
> 			proto_tree_add_text(icmp_tree, tvb, 12 + (i*8), 4,
> 								"Preference level: %u", tvb_get_ntohl(tvb, 12 + (i*8)));
> 		  }
> 		  if (icmp_code == 16) {
> 			/* Mobile-Ip */
> 			dissect_mip_extensions(tvb,8 + i*8, pinfo, icmp_tree);
> 		  }
> 		  
> 		} else
> 		  dissect_data(tvb, 8, pinfo, icmp_tree);
1659a1833,1885
> 
> 	{ &hf_icmp_mip_type,
> 	  { "Type", "icmp.mip.type",            FT_UINT8, BASE_DEC,
> 		VALS(mip_extensions), 0x0,"", HFILL}},
> 	{ &hf_icmp_mip_length,
> 	  { "Length", "icmp.mip.length",        FT_UINT8, BASE_DEC, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_prefix_length,
> 	  { "Prefix Length", "icmp.mip.prefixlength",  FT_UINT8, BASE_HEX, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_seq,
> 	  { "Sequence Number", "icmp.mip.seq",  FT_UINT16, BASE_HEX, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_life,
> 	  { "Registration Lifetime", "icmp.mip.life",  FT_UINT16, BASE_DEC, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_flags,
> 	  { "Flags", "icmp.mip.flags",            FT_UINT8, BASE_HEX, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_r,
> 	  {"Registration Required", "icmp.mip.r", FT_BOOLEAN, 8, NULL, 128,
> 	   "Registration with this FA is required", HFILL }},
> 	{ &hf_icmp_mip_b,
> 	  {"Busy", "icmp.mip.b", FT_BOOLEAN, 8, NULL, 64,
> 	   "This FA will not accept requests at this time", HFILL }},
> 	{ &hf_icmp_mip_h,
> 	  {"Home Agent", "icmp.mip.h", FT_BOOLEAN, 8, NULL, 32,
> 	   "Home Agent Services Offered", HFILL }},
> 	{ &hf_icmp_mip_f,
> 	  {"Foreign Agent", "icmp.mip.f", FT_BOOLEAN, 8, NULL, 16,
> 	   "Foreign Agent Services Offered", HFILL }},
> 	{ &hf_icmp_mip_m,
> 	  {"Minimal Encapsulation", "icmp.mip.m", FT_BOOLEAN, 8, NULL, 8,
> 	   "Minimal encapsulation tunneled datagram support", HFILL }},
> 	{ &hf_icmp_mip_g,
> 	  {"GRE", "icmp.mip.g", FT_BOOLEAN, 8, NULL, 4,
> 	   "GRE encapsulated tunneled datagram support", HFILL }},
> 	{ &hf_icmp_mip_v,
> 	  {"VJ Comp", "icmp.mip.v", FT_BOOLEAN, 8, NULL, 2,
> 	   "Van Jackobson Header Compression Support", HFILL }},
> 	{ &hf_icmp_mip_res,
> 	  {"Reserved", "icmp.mip.res", FT_BOOLEAN, 8, NULL, 1,
> 	   "Reserved", HFILL }},
> 
> 	{ &hf_icmp_mip_reserved,
> 	  { "Reserved", "icmp.mip.reserved",     FT_UINT8, BASE_HEX, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_coa,
> 	  { "Care-Of-Address", "icmp.mip.coa",    FT_IPv4, BASE_NONE, NULL, 0x0,
> 		"", HFILL}},
> 	{ &hf_icmp_mip_challenge,
> 	  { "Challenge", "icmp.mip.challenge",    FT_BYTES, BASE_NONE, NULL, 0x0,
> 		"", HFILL}},
1662a1889,1890
> 	&ett_icmp_mip,
> 	&ett_icmp_mip_flags

Attachment: icmp_mip_adv
Description: Binary data

Attachment: mip_reg.so
Description: Binary data