To all,
I've been looking at the S2K Usage (3.6.1) and, when using twofish as the
symmetrical algorithm (in say a type 0x00 S2K Usage), what do you do if you
want to use a 256 bit session key to encrypt the secret key? I'm assuming
here that S2K will only allow a session key equal to the symmetrical
algorithm block size...
If this is correct, what happens when 64 bit symmetrical algorithms are
used...is the session key length limited to only 64 bits?
Or...
Do you decide what length of the S2K session key to use (in your program),
then when the secret key needs to be extracted from the secret key-ring,
just keep trying multiple session key lengths in block size multiples (as
generated from the S2K specifier) until the checksum checks out OK?
It seems it would be a lot easier (maybe less secure?) if a session key
length was specified somewhere.
Cheers.
Regards
Erron Criddle
Comasp Ltd.
Level 2, 45 Stirling Hwy
NEDLANDS WA 6009
Australia
Fax: 08 9386 9473
Tel: 08 9386 9534
http://www.comasp.com
ejc(_at_)comasp(_dot_)com