dissector-skinny: Update skinny dissector to fix ServerRes Message

ServerRes message does not follow other message when it comes to
provinding the list of ip-addresses. The type of ip-address (IPv4
or IPv6 does not depend on the protocol version but the length of
the message.

Fix: ipv4 address displayed as ip-address

Change-Id: Ie16f81c9482b30a80da37b9327b09e933d7808f8
Reviewed-on: https://code.wireshark.org/review/10513
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>

epan/dissectors/packet-skinny.c

@@ -4880,6 +4880,8 @@ handle_RegisterRejectMessage(ptvcursor_t *cursor, packet_info * pinfo _U_)
 static void
 handle_ServerResMessage(ptvcursor_t *cursor, packet_info * pinfo _U_)
 {
+  guint32 hdr_data_length = tvb_get_letohl(ptvcursor_tvbuff(cursor), 0);
+
   {
     /* start struct : server / size: 48 */
     guint32 counter_1 = 0;
@@ -4901,18 +4903,35 @@ handle_ServerResMessage(ptvcursor_t *cursor, packet_info * pinfo _U_)
     }
     ptvcursor_pop_subtree(cursor); /* end for loop tree: serverTcpListenPort */
   }
-  {
-    /* start struct : serverIpAddr / size: 20 */
-    guint32 counter_1 = 0;
-    ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [max:5]");
-    for (counter_1 = 0; counter_1 < 5; counter_1++) {
-      ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [%d / %d]", counter_1 + 1, 5);
-      dissect_skinny_ipv4or6(cursor, hf_skinny_stationIpAddr_ipv4, hf_skinny_stationIpAddr_ipv6, pinfo);
+  if (hdr_data_length < 293) {
+    {
+      /* start struct : serverIpAddr / size: 4 */
+      guint32 counter_2 = 0;
+      ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [max:5]");
+      for (counter_2 = 0; counter_2 < 5; counter_2++) {
+        ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [%d / %d]", counter_2 + 1, 5);
+        ptvcursor_add(cursor, hf_skinny_stationIpAddr, 4, ENC_BIG_ENDIAN);
+        ptvcursor_pop_subtree(cursor);
+        /* end for loop tree: serverIpAddr */
+      }
       ptvcursor_pop_subtree(cursor);
-      /* end for loop tree: serverIpAddr */
+      /* end struct: serverIpAddr */
+    }
+  }
+  if (hdr_data_length > 292) {
+    {
+      /* start struct : serverIpAddr / size: 20 */
+      guint32 counter_2 = 0;
+      ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [max:5]");
+      for (counter_2 = 0; counter_2 < 5; counter_2++) {
+        ptvcursor_add_text_with_subtree(cursor, SUBTREE_UNDEFINED_LENGTH, ett_skinny_tree, "serverIpAddr [%d / %d]", counter_2 + 1, 5);
+        dissect_skinny_ipv4or6(cursor, hf_skinny_stationIpAddr_ipv4, hf_skinny_stationIpAddr_ipv6, pinfo);
+        ptvcursor_pop_subtree(cursor);
+        /* end for loop tree: serverIpAddr */
+      }
+      ptvcursor_pop_subtree(cursor);
+      /* end struct: serverIpAddr */
     }
-    ptvcursor_pop_subtree(cursor);
-    /* end struct: serverIpAddr */
   }
 }
 

tools/SkinnyProtocolOptimized.xml

@@ -812,7 +812,7 @@
   <message comment="" direction="dev2pbx" dynamic="no" name="OpenReceiveChannelAckMessage" opcode="0x0022" status="no" type="MediaControl">
     <fields>
       <enum comment="" name="openReceiveChannelStatus" subtype="MediaStatus" type="uint32"/>
-      <ipv4or6 comment="" name="ipAddr" subtype="IpAddress" type="ipaddr"/>
+      <ipv4or6 comment="" name="ipAddr" subtype="IPV4orV6Address" type="ipaddr"/>
       <integer comment="" name="portNumber" subtype="uint32" type="ipport" use_param="ipAddr"/>
       <integer comment="PassThrough PartyId" name="passThruPartyID" type="uint32"/>
     </fields>
@@ -2186,7 +2186,7 @@
     <fields>
       <integer comment="Conference ID" name="conferenceID" type="uint32"/>
       <integer comment="PassThrough PartyId" name="passThruPartyID" type="uint32"/>
-      <ipv4or6 comment="" name="remoteIpAddr" subtype="IpAddress" type="ipaddr"/>
+      <ipv4or6 comment="" name="remoteIpAddr" subtype="IPV4orV6Address" type="ipaddr"/>
       <integer comment="" name="remotePortNumber" subtype="uint32" type="ipport" use_param="remoteIpAddr"/>
       <integer comment="" name="millisecondPacketSize" type="uint32"/>
       <enum comment="" declare="yes" name="compressionType" subtype="Media_PayloadType" type="uint32"/>
@@ -2540,14 +2540,23 @@
     </fields>
   </message>
   <message comment="" direction="pbx2dev" dynamic="no" name="ServerResMessage" opcode="0x009e" status="no" type="RegistrationAndManagement">
-    <fields beginversion="0" endversion="22">
+    <fields>
       <struct comment="" name="server" size="5" subtype="ServerIdentifier" type="struct">
         <fields>
           <string comment="" name="ServerName" size="48" type="char"/>
         </fields>
       </struct>
       <integer comment="" name="serverTcpListenPort" size="5" type="uint32"/>
-      <struct comment="" name="serverIpAddr" size="5" subtype="IpAddress" type="struct">
+    </fields>
+    <fields size_lt="293">
+      <struct comment="Server IPv4 Address" name="serverIpAddr" size="5" subtype="IPv4Address" type="struct">
+        <fields>
+          <ip comment="ipaddress in big endian" endianness="big" name="stationIpAddr" type="ipv4"/>
+        </fields>
+      </struct>
+    </fields>
+    <fields beginversion="0" endversion="22" size_gt="292">
+      <struct comment="Server IP Address (IPv4or6)" name="serverIpAddr" size="5" subtype="IPV4orV6Address" type="struct">
         <fields>
           <ipv4or6 comment="ipaddress in big endian" endianness="big" name="stationIpAddr" size="16" subtype="uint8" type="ipaddr"/>
         </fields>
@@ -2707,7 +2716,7 @@
     <fields beginversion="11">
       <integer comment="" name="mixingMode" type="uint32"/>
       <integer comment="" name="partyDirection" type="uint32"/>
-      <ipv4or6 comment="" name="sourceIpAddr" subtype="IpAddress" type="ipaddr"/>
+      <ipv4or6 comment="" name="sourceIpAddr" subtype="IPV4orV6Address" type="ipaddr"/>
       <integer comment="" name="sourcePortNumber" subtype="uint32" type="ipport" use_param="sourceIpAddr"/>
     </fields>
     <fields beginversion="16">

tools/parse_xml2skinny_dissector.py

@@ -174,6 +174,11 @@ def xml2obj(src):
                 ret += self.indent_out("{\n")
                 self.incr_indent()
                 for fields in self.fields:
+                    if fields.size_lt:
+                        if self.basemessage.declared is None or "hdr_data_length" not in self.basemessage.declared:
+                            ret += self.indent_out("guint32 hdr_data_length = tvb_get_letohl(ptvcursor_tvbuff(cursor), 0);\n")
+                            self.basemessage.declared.append("hdr_data_length")
+                            declarations += 1
                     if fields.size_gt:
                         if self.basemessage.declared is None or "hdr_data_length" not in self.basemessage.declared:
                             ret += self.indent_out("guint32 hdr_data_length = tvb_get_letohl(ptvcursor_tvbuff(cursor), 0);\n")
@@ -232,6 +237,10 @@ def xml2obj(src):
                     ret += 'hdr_version <= V%s_MSG_TYPE) {\n' %self.endversion
                 self.incr_indent()
 
+            if self.size_lt:
+                ret += self.indent_out('if (hdr_data_length < %s) {\n' %self.size_lt)
+                self.incr_indent()
+
             if self.size_gt:
                 ret += self.indent_out('if (hdr_data_length > %s) {\n' %self.size_gt)
                 self.incr_indent()
@@ -240,6 +249,10 @@ def xml2obj(src):
             for field in self._children:
                 ret += '%s' %(field.dissect())
 
+            if self.size_lt:
+                self.decr_indent()
+                ret += self.indent_out('}\n')
+
             if self.size_gt:
                 self.decr_indent()
                 ret += self.indent_out('}\n')