I am trying to write a dynamic preprocessor for snort. i can make it through the ./configure make and make install stages without any problems. However, when i execute snort with this command

snort —dynamic-preprocessor-lib-dir /usr/local/lib/snort_dynamic-preprocessor

i am receiving this output :


--== Initializing Snort ==--
Initializing Output Plugins!
Loading all dynamic preprocessor libs from /usr/local/lib/snort_dynamicpreprocessor/...
Loading dynamic preprocessor library /usr/local/lib/snort_dynamicpreprocessor//libsf_smtp_preproc.so... done
Loading dynamic preprocessor library /usr/local/lib/snort_dynamicpreprocessor//libsf_ssh_preproc.so... done
Loading dynamic preprocessor library /usr/local/lib/snort_dynamicpreprocessor//libsf_gtp_preproc.so... done
Loading dynamic preprocessor library /usr/local/lib/snort_dynamicpreprocessor//libsf_EXAMPLE_preproc.so... ERROR: Failed to find LibVersion() function in /usr/local/lib/snort_dynamicpreprocessor//libsf_EXAMPLE_preproc.so: /usr/local/lib/snort_dynamicpreprocessor//libsf_EXAMPLE_preproc.so: undefined symbol: LibVersion


the error being here :

Loading dynamic preprocessor library /usr/local/lib/snort_dynamicpreprocessor//
libsf_EXAMPLE_preproc.so... ERROR: Failed to find LibVersion() function in /usr/local/lib/

snort_dynamicpreprocessor//libsf_EXAMPLE_preproc.so: /usr/local/lib/

snort_dynamicpreprocessor//libsf_EXAMPLE_preproc.so: undefined symbol: LibVersion


I have gone through my source code countless times.

Iam running Ubuntu 14.04 and Snort 2.9.7.3
Also, zlib-1.2.8 , libpcap - 1.7.4, daq-2.0.5

I am installing from source.

Any help or even advice on creating a preprocessor is greatly appreciated, i have been working on this far longer than i would of liked.

*While questions about Snort in the application sense may be security-related your question is about compiling, which is not. Hence I moved your question to the Programming form so it gets the exposure it deserves.

Note you are only showing information related to running Snort but not anything related to actually diagnosing dynamic preprocessor problems. What's missing is for example you comparing libraries each dynamic preprocessor uses, nfo on compiling your example like used includes, configure and compile log checking for errors and compile time use of say "-DHAVE_CONFIG_H".

You are trying to ask how to add a function called 'LibVersion' into your shared lib?