ASN Beginner

[David Murphy]

Hi - we are writing a small Java client to talk SSL to OpenSSL server (as a temporary test). This is a pilot to plug in SSL into a much bigger project. I receive the servers certificate during the SSL handshake in the server certificate message. This certificate seems to be in ASN (whatever that means) format according to the SSL spec. Question is how do I parse, decode or whatever this certificate data stream. >From what I understand, as a minimum, I need to pull out the server public key from the certificate for the rest of the SSL process - eg to create the master secret. Can anyone point me to some introductory doc on what ASN is and how to decode, parse it and how to pull out specific fields from the certificate. Is there a specification of what a certificate looks like. X509 seems to be some sort of standard for the certificate. Where is that explained or documented? How do I know if the certificate is X509? I have a bunch of "open source" Java source code that appears to be written to decode/parse ASN strcuctues but I have no idea how to present the certificate data to these classes.. Anyone else tried to code a Java SSL client? I assume I will hit other conceptual/learning type issues before I get thu this. I would love to hear from any one who has done this with Java and would be prepared to offer a little help thru this mail list. We have also looked at various Java SSL packages but concluded that they are all too heavy for use in applets - so we have to write code.. Thanks David Murphy