agent: Add option --pss to pksign to be used by smartcards.
* agent/command.c (cmd_sethash): Add option --pss and allow for --hash=null. * agent/agent.h (struct server_control_s): Add digest.is_pss and zero where needed. * agent/pksign.c (agent_pksign_do): Allow for PSS with cards. * scd/command.c (cmd_pksign): Add for --hash=none.
This is not a full implementaion of PSS but allows scdaemon card
drivers to detect already PSS formatted data.
- Signed-off-by: Werner Koch <wk@gnupg.org>