ecc.c data structures

[Sergi Blanch i Torné]

Hi,

I have a design doubt following the "ECC in OpenPGP"[1] draft that I like to 
discuss. I like the current internal structs: 'ECC_secret_key' and 
'ECC_public_key'. They have the elliptic curve (as 'elliptic_curve_t'), the 
public key (as 'mpi_point_t') and, if it's the case, the secret key (as 
'gcry_mpi_t').

Not all the data from the draft can be stored in this structs as they are. The 
low level hash and symmetric algorithms ID has to be stored, but other 
information like the curve OID and the fingerprint also is need for KDF (Key 
Derivation Function)

First of all, how can be better to be structured? Would I define something like 
ECC_param_t and put it in the 'ECC_{secret,public}_key' structs? Or can be 
more elegant to have this in the struct of the context mpi_ec_t? This params 
are only necessary for encrypt, and this may disturb in this proposed places.

The second issue I have now is the fingerprint I mention. I don't know how can 
I have this information in side a libgcrypt module. The kdf algorithm uses 
this data, but from where this has to be written I don't know who to access 
it.

By now this. More issues will come soon... Thanks.

/Sergi.

[1]: http://sites.google.com/site/brainhub/pgp