why gpg use SHA1 instead of pref???

David Shaw dshaw at jabberwocky.com
Thu Mar 22 23:54:53 CET 2007

On Thu, Mar 22, 2007 at 11:12:26AM +0000, redstar wrote:

> New: Symmetrically Encrypted and MDC Packet(tag 18)(70 bytes)
> 	Ver 1
> 	Encrypted data [sym alg is specified in pub-key encrypted session key]
> 		(plain text + MDC SHA1(20 bytes))
> What I must do for using RIPEMD160 hash of encryption??? Its normal because
> encryption specifications requirements? Or its error of gpg?

The MDC is always SHA-1.  It is fixed as part of the protocol.

> Why he will use RSA encryption as other symmetric ciphers like CAST5, 3DES,
> BLOWFISH,, in prefs, and, RSA its not in prefs list?

The type of public-key encryption is defined by what type of key you
are encrypting to.  An RSA key means RSA encryption.  The symmetric
ciphers are not relevant to this question.


More information about the Gnupg-users mailing list