passphrase for symmetric encryption // ?maximum length

Werner Koch wk at gnupg.org
Wed Jan 24 10:43:51 CET 2007


On Wed, 24 Jan 2007 00:27, vedaal at hush.com said:

> is there a maximum beyond which gnupg will just 'refuse' the 
> passphrase,

There should be no such limit.  The exception ist hat you may run out
of memory.  The passphrase is hold in secure memory and during
computations 2 or 3 copies need to be stored there.  1000 characters
should be no problem but it makes no sense.

> or is there an effective maximum, where longer passphrases make no 
> difference?

See Robert's answer.  Depending on the choosen cipher you may need
more that 128 bits, though.


Salam-Shalom,

   Werner




More information about the Gnupg-users mailing list