Add dissectors inside GSM-MAP protocol dissector

Question

Hello, i have some extra tags that i would like to decode inside a GSM-MAP message. So i decided to add my dissector code inside the allready defined code for GSM-MAP (edit /epan/dissector/packet-gsm_map.c file). After adding my impacts inside the existing code i tried to build again the source code, after the compilation of the new gsm_map.c file compiler came up with some errors inside gsm_map.cnf file displaying the extra data and structures added. Below you can se some logs of the errors

"ett_gsm_map_lsc_XXX" undeclared identifier
"dissect_gsm_map_lsc_XXX" undeclared identifier
"initializer is not a contstant"
etc.

Inside the error logs the gsm_map.cnf file appears. I think i should edit and update accordingly the gsm_map.cnf file but i dont know how Any idea?

Answer 1

The erroneous line indicated by the compiler is somewhat of a red herring as the packet-gsm_map.c is a generated file there is statements like this #line 227 "./asn1/gsm_map/gsm_map.cnf" generated in the code so the compiler will refer to offsets of those. It is possible to edit packet-gsm_map.c and make it compile but "right" way would be to edit the ASN1 files with your new tags and regenerate the file I suppose.