Re: Royalty free crypto library?

From: Gleb Esman (
Date: 04/18/03

From: "Gleb Esman" <>
Date: Fri, 18 Apr 2003 12:56:40 -0700

Thanks Bryan. I guess i cannot use GnuPG team's Libgcrypt if i plan to
charge for my software?
And yes, i need to sign a piece of text (with private key) and verify (with
public key) function. Nothing else really.
I'll check Crypto++, i hope they'll have a good help file and royalty free
arrangement for commercial products as well.
My challenge is to find the way to wrap a multitude of functions with
mysterious names and purpose into 2 simple wrappers for sign and verify.
I've checked a few packages but their docs for non-crypto-geniuses wasn't
too helpful.

Gleb Esman

"Bryan Olson" <> wrote in message
> Gleb Esman wrote:
> > I am working on email enhancement filter that would include simple
> > public/private key based authentication. I am neither math, nor crypto
> > expert. I would like to have 2 functions:
> > Generate_public_and_private_pair_of_keys (...);
> > Encrypt_Decrypt_data_buffer (void *public_or_private_key, char *buffer,
> > buffer_size);
> >
> > I'd like to use royalty free code without violating anyone legal or
> > rights. I do not need super strong encryption, but of course the
> > the better.
> >
> > Is it possible? Could anyone help me in that (without laughing) ?
> Ha ha ha. Oh, sorry.
> First, the class act in free crypto libraries is Wei Dai's
> Crypto++, which you can find at:
> A possible alternative would be GnuPG team's Libgcrypt, but the
> current version is a beta release. See:
> The library is under the GLPL, so you can use for free, even in
> non-open software. (Gnu Privacy Guard itself is free under the
> GPL, so it's free and all derivative works must also be free.
> That's an over-simplification, see the GPL and GLPL for the
> real conditions.)
> Keep an open mind about what functions you need. You mention
> authentication (and don't mention privacy), so really you want a
> sign function and a verify function. Useful software always
> needs enhancement, so build crypto features on established
> standards and methods.
> --
> --Bryan