From: yermej <yermej@...>
Date: 2008-01-24T00:04:58+09:00
Subject: Re: What these lines of code do?

On Jan 23, 8:40 am, Jano Svitok <jan.svi...@gmail.com> wrote:
> On Jan 23, 2008 3:05 PM, MohsinHijazee <mohsinhija...@gmail.com> wrote:
>
> > # What this is doing? I mean Digest.new('sha1') returns what?
> >   digest = OpenSSL::Digest::Digest.new('sha1')
>
> > # Is it so that we say HMAC.digest to use the SHA1 algorithm?
> >   hmac = OpenSSL::HMAC.digest(digest, SECRET_KEY, uri)
>
> > # What the chomp method does?
> >   signature = Base64.encode64(hmac).chomp
>
> > Asking these questions as they are not documented in the Ruby
> > documentation.
>
> > Regards,
> > Mohsin
>
> http://ruby-doc.org/stdlib/libdoc/openssl/rdoc/index.html

There really isn't any useful documentation at that URL. You can see
the source of some methods, but there's still no explanation of terms
or how everything fits together. There are also some important classes
missing (SSLContext, Certificate).

http://en.wikipedia.org/wiki/Cryptographic_hash_function might be your
best bet for the two OpenSSL questions. Once you know what the various
terms mean, you can apply that knowledge to any crypto library.

You can also find some info in the docs at openssl.org, but they
aren't Ruby specific and won't help much if you don't have at least
some knowledge of the terms involved. I've found the O'Reilly book
'Network Security with OpenSSL' to be pretty helpful, but it isn't
Ruby specific either. There are also some simple examples packaged
with the Ruby source in ruby-1.8.6/sample/openssl that are helpful in
fitting the pieces together.