agent: Allow NULL for R_PADDING, when calling scd and tpm2d.

* agent/call-scd.c (padding_info_cb): Allow NULL.
(agent_card_pkdecrypt): Likewise.
* agent/divert-scd.c (divert_pkdecrypt): Likewise.
* agent/divert-tpm2.c (divert_tpm2_pkdecrypt): Likewise.

--

It's for RSA PKCD#1 encoding if the decrypt operation removes padding
or not.  When caller knows it's not RSA, this information is no use
and it is better to allow NULL with the variable R_PADDING.

Signed-off-by: NIIBE Yutaka <[email protected]>

1 files changed, 6 insertions, 4 deletions

diff --git a/agent/call-scd.c b/agent/call-scd.c
index 91e28e68c..3da16e619 100644
--- a/agent/call-scd.c
+++ b/agent/call-scd.c
@@ -548,7 +548,8 @@ padding_info_cb (void *opaque, const char *line)
 
   if ((s=has_leading_keyword (line, "PADDING")))
     {
-      *r_padding = atoi (s);
+      if (r_padding)
+        *r_padding = atoi (s);
     }
   else if ((s=has_leading_keyword (line, "PINCACHE_PUT")))
     err = handle_pincache_put (s);
@@ -560,8 +561,8 @@ padding_info_cb (void *opaque, const char *line)
 /* Decipher INDATA using the current card.  Note that the returned
  * value is not an s-expression but the raw data as returned by
  * scdaemon.  The padding information is stored at R_PADDING with -1
- * for not known.  DESC_TEXT is an additional parameter passed to
- * GETPIN_CB.  */
+ * for not known, when it's not NULL.  DESC_TEXT is an additional
+ * parameter passed to GETPIN_CB.  */
 int
 agent_card_pkdecrypt (ctrl_t ctrl,
                       const char *keyid,
@@ -579,7 +580,8 @@ agent_card_pkdecrypt (ctrl_t ctrl,
   size_t len;
 
   *r_buf = NULL;
-  *r_padding = -1; /* Unknown.  */
+  if (r_padding)
+    *r_padding = -1; /* Unknown.  */
   rc = start_scd (ctrl);
   if (rc)
     return rc;