Wireshark · Ethereal-dev: [Ethereal-dev] DHCPv6 patch

[Tomasz Mrugalski <thomson@xxxxxxxxxxx>]

Hi there

My name is Tomasz Mrugalski I've found out that Ethereal parsing of the 
DHCPv6 frames is rather outdated. I've downloaded 0.10.7 and made some 
improvements to the packet-dhcpv6.c file. Result of this command: diff -u 
packet-dhcpv6.c packet-dhcpv6.c-new is attached to this mail. If you're 
interesed in the whole file, you can download it form here: 
http://klub.com.pl/dhcpv6/packet-dhcpv6.c

Here's quick list of the changes:
- option values updated to match RFC3898 (NIS/NIS+ options)
- FQDN option added (draft-ietf-dhc-dhcpv6-opt-fqdn-00.txt)
- Lifetime option added (draft-ietf-dhc-dhcpv6-opt-lifetime-00.txt)
- Long lasting typo corrected (those are identiTy associations, not
  identiFy associations)
- Fixed bug always reporting SIP DOMAIN option to be malformed (break was
  missing)
- Domains names are now parsed (in DOMAIN_LIST, SIP_SERVER_A, NIS_DOMAIN
  and NISPLUS_DOMAIN options).

I can provide proper dumps to verify that those parsers work ok, if you 
are interested.

That's all.

BTW: Ethereal is great. Good work guys!

--
Tomasz Mrugalski,          | "We all know Linux is great...it does    |
thomson@xxxxxxxxxxx        |  infinite loops in 5 seconds."           |
                           |                           Linus Torvalds |

--- packet-dhcpv6.c	2004-10-21 00:34:59.000000000 +0200
+++ packet-dhcpv6.c-new	2004-11-30 01:59:24.000000000 +0100
@@ -4,16 +4,20 @@
  * IItom Tsutomu MIENO <iitom@xxxxxxxxxx>
  * SHIRASAKI Yasuhiro <yasuhiro@xxxxxxxxxxx>
  * Tony Lindstrom <tony.lindstrom@xxxxxxxxxxxx>
+ * Tomasz Mrugalski <thomson@xxxxxxxxxxx>
  *
- * $Id: packet-dhcpv6.c 12173 2004-10-01 12:35:55Z jmayer $
+ * $Id: packet-dhcpv6.c,v 1.1 2004/11/30 00:59:24 thomson Exp $
  *
  * The information used comes from:
- * RFC3315.txt
- * RFC3319.txt
- * RFC3633.txt
- * RFC3646.txt
- * draft-ietf-dhc-dhcpv6-opt-nisconfig-02.txt
- * draft-ietf-dhc-dhcpv6-opt-timeconfig-02.txt
+ * RFC3315.txt (DHCPv6)
+ * RFC3319.txt (SIP options)
+ * RFC3633.txt (Prefix options)
+ * RFC3646.txt (DNS servers/domains)
+ * RFC3898.txt (NIS options)
+ * draft-ietf-dhc-dhcpv6-opt-timeconfig-03.txt
+ * draft-ietf-dhc-dhcpv6-opt-fqdn-00.txt
+ * draft-ietf-dhc-dhcpv6-opt-lifetime-00.txt
+ *
  * Note that protocol constants are still subject to change, based on IANA
  * assignment decisions.
  *
@@ -47,6 +51,10 @@
 
 static int proto_dhcpv6 = -1;
 static int hf_dhcpv6_msgtype = -1;
+static int hf_fqdn_1 = -1;
+static int hf_fqdn_2 = -1;
+static int hf_fqdn_3 = -1;
+static int hf_fqdn_4 = -1;
 
 static gint ett_dhcpv6 = -1;
 static gint ett_dhcpv6_option = -1;
@@ -96,16 +104,18 @@
 #define	OPTION_DOMAIN_LIST      24
 #define	OPTION_IA_PD		25
 #define	OPTION_IAPREFIX		26
+#define OPTION_NIS_SERVERS	27
+#define OPTION_NISP_SERVERS	28
+#define OPTION_NIS_DOMAIN_NAME  29
+#define OPTION_NISP_DOMAIN_NAME 30
 
 /*
  * The followings are unassigned numbers.
  */
-#define OPTION_NIS_SERVERS	35
-#define OPTION_NISP_SERVERS	36
-#define OPTION_NIS_DOMAIN_NAME  37
-#define OPTION_NISP_DOMAIN_NAME 38
-#define OPTION_NTP_SERVERS	40
+#define OPTION_CLIENT_FQDN      34
+#define OPTION_SNTP_SERVERS	40
 #define OPTION_TIME_ZONE	41
+#define OPTION_LIFETIME         42
 
 #define	DUID_LLT		1
 #define	DUID_EN			2
@@ -132,8 +142,8 @@
 static const value_string opttype_vals[] = {
 	{ OPTION_CLIENTID,	"Client Identifier" },
 	{ OPTION_SERVERID,	"Server Identifier" },
-	{ OPTION_IA_NA,		"Identify Association" },
-	{ OPTION_IA_TA,		"Identify Association for Temporary Address" },
+	{ OPTION_IA_NA,		"Identity Association" },
+	{ OPTION_IA_TA,		"Identity Association for Temporary Address" },
 	{ OPTION_IAADDR,	"IA Address" },
 	{ OPTION_ORO,		"Option Request" },
 	{ OPTION_PREFERENCE,	"Preference" },
@@ -154,14 +164,16 @@
 	{ OPTION_SIP_SERVER_A,	"SIP Servers IPv6 Address List" },
 	{ OPTION_DNS_SERVERS,	"DNS recursive name server" },
 	{ OPTION_DOMAIN_LIST,	"Domain Search List" },
-	{ OPTION_IA_PD,		"Identify Association for Prefix Delegation" },
+	{ OPTION_IA_PD,		"Identity Association for Prefix Delegation" },
 	{ OPTION_IAPREFIX,	"IA Prefix" },
 	{ OPTION_NIS_SERVERS,	"Network Information Server" },
 	{ OPTION_NISP_SERVERS,	"Network Information Server V2" },
 	{ OPTION_NIS_DOMAIN_NAME, "Network Information Server Domain Name" },
 	{ OPTION_NISP_DOMAIN_NAME,"Network Information Server V2 Domain Name" },
-	{ OPTION_NTP_SERVERS,	"Network Time Protocol Server" },
+	{ OPTION_SNTP_SERVERS,	"Simple Network Time Protocol Server" },
 	{ OPTION_TIME_ZONE,	"Time zone" },
+	{ OPTION_LIFETIME,      "Lifetime" },
+	{ OPTION_CLIENT_FQDN,   "Fully Qualified Domain Name" },
 	{ 0,	NULL }
 };
 
@@ -186,11 +198,58 @@
 	{ 0, NULL }
 };
 
+static const true_false_string tfs_present = {
+    "present",
+    "absent"
+};
+
+/* This FQDN draft is a mess, I've tried to understand, 
+   but N,O,S bit descriptions are really cryptic */
+static const true_false_string fqdn_n = {
+/*    "Client doesn't want server to perform DNS update", "" */
+    "N bit set","N bit cleared"
+};
+
+static const true_false_string fqdn_o = {
+    "O bit set", "O bit cleared" 
+};
+
+static const true_false_string fqdn_s = {
+/*    "Forward mapping (FQDN-to-IPv6, AAAA) performed by client", 
+      "Forward mapping (FQDN-to-IPv6, AAAA) performed by server" */
+    "S bit set", "S bit cleared"
+}; 
+
+/* Adds domain */
+static void
+dhcpv6_domain(proto_tree * subtree, tvbuff_t *tvb, int off, guint16 optlen)
+{
+    guint8 domain[256];
+    guint8 count = 0;
+    guint8 len = 0;
+    while (optlen) {
+	count++;
+	tvb_memcpy(tvb, (guint8*)&len, off, 1);
+	if (len==0)
+	    break;
+	if (len>optlen) {
+	    proto_tree_add_text(subtree, tvb, off, optlen, "Malformed option");
+	    return;
+	}
+	tvb_memcpy(tvb, (guint8*)&domain, off+1, len);
+	domain[len]=0;
+	proto_tree_add_text(subtree, tvb, off, len+1, "Domain: %s", domain);
+	off    += len+1;
+	optlen -= len+1;
+    };
+}
+
 /* Returns the number of bytes consumed by this option. */
 static int
 dhcpv6_option(tvbuff_t *tvb, proto_tree *bp_tree, int off, int eoff,
     gboolean *at_end)
 {
+        guint8  buf[255];
 	guint16	opttype;
 	guint16	optlen;
 	guint16	temp_optlen = 0;
@@ -300,10 +359,21 @@
 	  proto_tree_add_text(subtree, tvb, off, 4,
 			      "IAID: %u",
 			      tvb_get_ntohl(tvb, off));
-	  proto_tree_add_text(subtree, tvb, off+4, 4,
-			      "T1: %u", tvb_get_ntohl(tvb, off+4));
-	  proto_tree_add_text(subtree, tvb, off+8, 4,
-			      "T2: %u", tvb_get_ntohl(tvb, off+8));
+	  if (tvb_get_ntohl(tvb, off+4) == DHCPV6_LEASEDURATION_INFINITY) {
+	    proto_tree_add_text(subtree, tvb, off+4, 4,
+				"T1: infinity");
+	  } else {
+	    proto_tree_add_text(subtree, tvb, off+4, 4,
+				"T1: %u", tvb_get_ntohl(tvb, off+4));
+	  }
+
+	  if (tvb_get_ntohl(tvb, off+8) == DHCPV6_LEASEDURATION_INFINITY) {
+	    proto_tree_add_text(subtree, tvb, off+8, 4,
+				"T1: infinity");
+	  } else {
+	      proto_tree_add_text(subtree, tvb, off+8, 4,
+				  "T2: %u", tvb_get_ntohl(tvb, off+8));
+	  }
 
           temp_optlen = 12;
 	  while ((optlen - temp_optlen) > 0) {
@@ -526,6 +596,8 @@
 			proto_tree_add_text(subtree, tvb, off, optlen,
 				"SIP Servers Domain Search List");
 		}
+		dhcpv6_domain(subtree,tvb, off, optlen);
+		break;
 	case OPTION_SIP_SERVER_A:
 		if (optlen % 16) {
 			proto_tree_add_text(subtree, tvb, off, optlen,
@@ -556,6 +628,7 @@
 	  if (optlen > 0) {
 	    proto_tree_add_text(subtree, tvb, off, optlen, "DNS Domain Search List");
 	  }
+	  dhcpv6_domain(subtree,tvb, off, optlen);
 	  break;
 	case OPTION_NIS_SERVERS:
 		if (optlen % 16) {
@@ -587,30 +660,63 @@
 	  if (optlen > 0) {
 	    proto_tree_add_text(subtree, tvb, off, optlen, "nis-domain-name");
 	  }
+	  dhcpv6_domain(subtree,tvb, off, optlen);
 	  break;
 	case OPTION_NISP_DOMAIN_NAME:
 	  if (optlen > 0) {
 	    proto_tree_add_text(subtree, tvb, off, optlen, "nisp-domain-name");
 	  }
+	  dhcpv6_domain(subtree,tvb, off, optlen);
 	  break;
-	case OPTION_NTP_SERVERS:
+	case OPTION_SNTP_SERVERS:
 		if (optlen % 16) {
 			proto_tree_add_text(subtree, tvb, off, optlen,
-				"NTP servers address: malformed option");
+				"SNTP servers address: malformed option");
 			break;
 		}
 		for (i = 0; i < optlen; i += 16) {
 			tvb_memcpy(tvb, (guint8 *)&in6, off + i, sizeof(in6));
 			proto_tree_add_text(subtree, tvb, off + i,
-				sizeof(in6), "NTP servers address: %s",
+				sizeof(in6), "SNTP servers address: %s",
 				ip6_to_str(&in6));
 		}
 		break;
 	case OPTION_TIME_ZONE:
 	  if (optlen > 0) {
-	    proto_tree_add_text(subtree, tvb, off, optlen, "time-zone");
+	    tvb_memcpy(tvb, (guint*)buf, off, optlen);
+	    buf[optlen]=0;
+	    proto_tree_add_text(subtree, tvb, off, optlen, "time-zone: %s", buf);
+	  }
+	  break;
+	case OPTION_LIFETIME:
+	  if (optlen != 4) {
+	    proto_tree_add_text(subtree, tvb, off,
+				optlen, "LIFETIME: malformed option");
+	    break;
+	  }
+	  proto_tree_add_text(subtree, tvb, off, 4,
+			      "Lifetime: %d",
+			      (guint32)tvb_get_ntohl(tvb, off));
+	  break;
+	case OPTION_CLIENT_FQDN:
+	  if (optlen < 1) {
+	    proto_tree_add_text(subtree, tvb, off,
+				optlen, "FQDN: malformed option");
+	    break;
 	  }
+	  // +-----+-+-+-+
+	  // | MBZ |N|O|S|
+	  // +-----+-+-+-+
+	  proto_tree_add_item(subtree, hf_fqdn_1, tvb, off, 1, FALSE);
+	  proto_tree_add_item(subtree, hf_fqdn_2, tvb, off, 1, FALSE);
+	  proto_tree_add_item(subtree, hf_fqdn_3, tvb, off, 1, FALSE);
+	  proto_tree_add_item(subtree, hf_fqdn_4, tvb, off, 1, FALSE);
+/* 	  proto_tree_add_text(subtree, tvb, off, 1, */
+/* 			      "flags: %d", */
+/* 			      (guint32)tvb_get_guint8(tvb, off)); */
+	  dhcpv6_domain(subtree,tvb, off+1, optlen-1);
 	  break;
+
 	case OPTION_IAPREFIX:
 	    {
 		guint32 preferred_lifetime, valid_lifetime;
@@ -786,11 +892,25 @@
 proto_register_dhcpv6(void)
 {
   static hf_register_info hf[] = {
+
     { &hf_dhcpv6_msgtype,
       { "Message type",			"dhcpv6.msgtype",	 FT_UINT8,
          BASE_DEC, 			VALS(msgtype_vals),   0x0,
       	"", HFILL }},
-  };
+    
+    { &hf_fqdn_1,
+      { "Reserved", "", FT_UINT8, BASE_HEX, NULL, 0xF8, "", HFILL}},
+    { &hf_fqdn_2,
+      { "N", "", FT_BOOLEAN, 8, TFS(&fqdn_n), 0x4, "", HFILL}},
+    { &hf_fqdn_3,
+      { "O", "", FT_BOOLEAN, 8, TFS(&fqdn_o), 0x2, "", HFILL}},
+    { &hf_fqdn_4,
+      { "S", "", FT_BOOLEAN, 8, TFS(&fqdn_s), 0x1, "", HFILL}}
+    
+  }
+
+
+;
   static gint *ett[] = {
     &ett_dhcpv6,
     &ett_dhcpv6_option,