I'm not sure what you mean by masking the data, but if you have control characters and such in the file, you need to clean the data before importing it.
You could have a separate generic task/job that removes these type of characters from a file that you pass in as param. This can be done with eg regex.
Anyway, just to repeat what Gary said in his comment. Use built in db features. You are using Oracle. They have something called Extrernal tables. If you are not familiar with it, look it up. They are awesome for importing data from files into tables. you can clean the data, insert and log errors all in one go.