[Ethereal-dev] Malformed packet

[ana <ana@xxxxxxxxxxxxxxx>]

Hi!

I continuos working on the DSR (Dynamic Source Route) protocol. The 
report Malformed packet is in every packet. It will be caused by the 
offset declaration, I don't know really. Perhaps you can take a look to 
the code and see the problem.

This is the dissector code:

guint8 optdatalen,offset= 0x00;
guint16 header_len;

while ((header_len-offset)!=0)
           {

           pdu_type = tvb_get_guint8(tvb,4+offset);
           optdatalen = tvb_get_guint8(tvb,5+offset);

           switch (pdu_type)
               {

                 case DSR_ROUTE_REQ:
                       tf = proto_tree_add_uint(dsr_tree, 
hf_dsr_pdutype, tvb, 4+offset, 1, pdu_type);
                       pdutype_tree = proto_item_add_subtree(tf, 
ett_dsr);    
                                          
                      proto_tree_add_uint(pdutype_tree, 
hf_dsr_optdatalen, tvb, 5+offset, 1, optdatalen);
                      break;
                 case DSR_SRC_ROUTE:
                       tf = proto_tree_add_uint(dsr_tree, 
hf_dsr_pdutype, tvb, 4+offset, 1, pdu_type);
                       pdutype_tree  = proto_item_add_subtree(tf, 
ett_dsr);  
                                   
                       proto_tree_add_uint(pdutype_tree, 
hf_dsr_optdatalen, tvb, 5+offset, 1, optdatalen);
                       break;  
                   case DSR_ROUTE_REPLY:
                       tf = proto_tree_add_uint(dsr_tree, 
hf_dsr_pdutype, tvb, 4+offset, 1, pdu_type);
                       pdutype_tree  = proto_item_add_subtree(tf, 
ett_dsr);  

                       proto_tree_add_uint(pdutype_tree, 
hf_dsr_optdatalen, tvb, 5+offset, 1, optdatalen);
                       break;   
              }
           header_len-=(optdatalen+2);

           if (pdu_type==DSR_PAD0)
               optdatalen+=1;
           else
               optdatalen+=2;

           offset+=optdatalen;
          
           }

Hope toy can help me.
Thanks in advanced,

Ana Rodriguez
Spain