As recommended by toolic above, Convert::ASN1 is good - it replaces Convert::BER IIRC. I've used both in the past, but upgraded all my uses to Convert::ASN1 for decoding.

At the very least, throw your data at the Convert::ASN1 asn_dump function - it will try to decode your data automagically! A brilliant piece of code from which I was able to write correct parsers for the specific data format I was looking to decode.