Adam Back writes:
Could we call ElGamal ElGamal, please?
It's not just a nit, what happens when someone wants to put real DH
into the spec, are you going to call it "realDH" or "DH2"?
Actually the algorithm identifiers in the 5.0 source are:
PGP_PKALG_RSA
PGP_PKALG_ELGAMAL
PGP_PKALG_DSA
It has always been called ElGamal in the source.
In the past, Adam and I have discussed the question of how proper it is
to refer to ElGamal as a variant of Diffie-Hellman. This is an issue of
terminology and people may differ in their preferred usage.
In my opinion, DH strictly refers to a key exchange algorithm which
requires messages to flow both ways, and cannot be used for email in
that form. There are several ways in which DH can be adapted to the
requirement for one-way communication, which have various pros and cons
with respect to multiple recipients, shared primes, and other issues.
ElGamal is one such method.
It is possible in the future that we could support other forms of
encryption that fall into the DH "family", but I don't think it would
be proper to single any of these out and call it DH to the exclusion
of the others. So I don't think we will ever have "Diffie-Hellman"
as a public key encryption algorithm.
Hal