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 <[email protected]>

1 files changed, 5 insertions, 3 deletions

diff --git a/agent/agent.h b/agent/agent.h
index 7ef0ffca7..7f18eb601 100644
--- a/agent/agent.h
+++ b/agent/agent.h
@@ -254,12 +254,14 @@ struct server_control_s
   /* Information on the currently used digest (for signing commands).  */
   struct {
     char *data;    /* NULL or malloced data of length VALUELEN.  If
-                      this is set The other fields are ignored.  Used
-                      for PureEdDSA. */
+                      this is set the other fields are ignored.  Used
+                      for PureEdDSA and RSA with PSS (in which case
+                      data_is_pss is also set).  */
     int valuelen;
     int algo;
     unsigned char value[MAX_DIGEST_LEN];
-    int raw_value: 1;
+    unsigned int raw_value: 1;
+    unsigned int is_pss: 1;    /* DATA holds PSS formated data.  */
   } digest;
   unsigned char keygrip[20];
   int have_keygrip;