Create off-line card encryption key with the right size.

* g10/keygen.c (gen_card_key_with_backup): Get the size of the key
from the card.
--

Formerly the off-line encryption key was created with a fixed length
of 1024 bit.  With this change the key is created as expected.

GnuPG-bug-id: 1230

1 files changed, 16 insertions, 1 deletions

diff --git a/g10/keygen.c b/g10/keygen.c
index 7c473cbaf..30ec370c6 100644
--- a/g10/keygen.c
+++ b/g10/keygen.c
@@ -3711,10 +3711,25 @@ gen_card_key_with_backup (int algo, int keyno, int is_primary,
   PKT_public_key *pk;
   size_t n;
   int i;
+  unsigned int nbits;
 
   sk_unprotected = NULL;
   sk_protected = NULL;
-  rc = generate_raw_key (algo, 1024, timestamp,
+
+  /* Get the size of the key directly from the card.  */
+  {
+    struct agent_card_info_s info;
+
+    memset (&info, 0, sizeof info);
+    if (!agent_scd_getattr ("KEY-ATTR", &info)
+        && info.key_attr[1].algo)
+      nbits = info.key_attr[1].nbits;
+    else
+      nbits = 1024; /* All pre-v2.0 cards.  */
+    agent_release_card_info (&info);
+  }
+
+  rc = generate_raw_key (algo, nbits, timestamp,
                          &sk_unprotected, &sk_protected);
   if (rc)
     return rc;