ietf-openpgp
[Top] [All Lists]

Re: [openpgp] PKI (RFC 5480) mapping to ECC keys (RFC 6637)

2013-07-19 15:33:36
On Fri, 19 Jul 2013, Andrey Jivsov wrote:

You can't use 20 because it was used for Elgamal in rfc2440.  A new one
needs to be allocated.  22 would be the next.

Indeed.

I was thinking about recycling ID 20, given that there is small benefit for the IDs to be consecutive.

The simplification is generic. Now that we would have 3 IDs for ECC, it is more efficient to check 18 <= x <= 20 then for 3 arbitrary IDs. Also, consecutive IDs allow easy transition to zero-based indexing (just subtract 18).

Those "benefits" are just coding errors waiting to happen in the future. A
switch statement seems much more appropriate.

Current definition of 20 in RFC 4880 is:

  20         - Reserved (formerly Elgamal Encrypt or Sign)

In RFC 2440 it is:

  20         - Elgamal (Encrypt or Sign)

Do we know of at least one case when 20 is used in deployed applications? This will be enough to require 22 for ECDSA+ECDH.

Even with no implementation out there, the allocated numbers should not be
recycled, unless in extreme use cases, eg where we've ran out of
numbers.

Paul
_______________________________________________
openpgp mailing list
openpgp(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/openpgp