BouncyCastle Java - Decoding DER encoded OCTET strings

Question

I'm reading in a CER certificate file which gives me an X.509 certificate object.

There are several extensions that contain DER encoded OCTET strings. e.g.:

Certificate Extensions: 9
[1]: ObjectId: 1.3.6.1.4.1.311.21.10 Criticality=false
Extension unknown: DER encoded OCTET string =
0000: 04 1C 30 1A 30 0A 06 0B   2B 06 01 04 01 82 37 2F  ..0.0...+.....7/
0010: 01 01 30 0E 06 08 2B 06   01 05 05 07 03 02        ..0...+.......

How can I decode these strings using BouncyCastle

Answer 1

Google told me to look at the class: JcaX509ExtensionUtils

Now it's up to you.