default Cipher and Pubkey algo
Andrew McDonald
andrew@mcdonald.org.uk
Wed Mar 7 23:22:12 2001
On Wed, Mar 07, 2001 at 10:24:28PM +0100, Georg Wilckens wrote:
>
> The thing I am wondering about is, how I can find out which cipher
> algorithm is selected in the preferences of a given key. Is this
> implemented yet?
You can find out the preferences from the edit-key command, e.g.
-X-X-
admcd@bifrons:~$ gpg --edit-key 0xf2deed36
Secret key is available.
pub 1024D/F2DEED36 created: 1999-11-01 expires: never trust: -/u
sub 2048g/FA04439F created: 1999-11-01 expires: never
(1) Andrew McDonald <andrew@mcdonald.org.uk>
(2) Andrew McDonald <A.D.McDonald@bcs.org.uk>
Command> pref
pub 1024D/F2DEED36 created: 1999-11-01 expires: never trust: -/u
(1) Andrew McDonald <andrew@mcdonald.org.uk>
S7 S10 S3 S4 H3 H2 Z2 Z1
(2) Andrew McDonald <A.D.McDonald@bcs.org.uk>
S7 S10 S3 S4 H3 H2 Z2 Z1
-X-X-
The 'S' is the symmetric cipher preference. 'H' is hash algorithm. 'Z'
is compression. You can find out what the numbers mean from RFC2440.
e.g. for the symmetric encryption:
[actually this is the list from the RFC2440-bis Internet Draft -
algorithm 10 isn't specified in RFC2440]
-X-X-
9.2. Symmetric Key Algorithms
ID Algorithm
-- ---------
0 - Plaintext or unencrypted data
1 - IDEA [IDEA]
2 - Triple-DES (DES-EDE, [SCHNEIER] -
168 bit key derived from 192)
3 - CAST5 (128 bit key, as per RFC2144)
4 - Blowfish (128 bit key, 16 rounds) [BLOWFISH]
5 - SAFER-SK128 (13 rounds) [SAFER]
6 - Reserved for DES/SK [AES]
7 - AES with 128-bit key
8 - AES with 192-bit key
9 - AES with 256-bit key
10 - Twofish with 256-bit key [TWOFISH]
100 to 110 - Private/Experimental algorithm.
-X-X-
So, for my key shown above the preferences are AES, Twofish, CAST5,
Blowfish. Triple-DES is also implied as being at the end of the list,
since support for it is required by an OpenPGP implementation.
Andrew
--
Andrew McDonald
E-mail: andrew@mcdonald.org.uk
http://www.mcdonald.org.uk/andrew/