[PATCH] Changes for EdDSA (1/3)

[NIIBE Yutaka]

Here are small changes for EdDSA support.

(1) EdDSA a public key shoud have "(flags eddsa)" in the S-expression
    to compute its keygrip (in g10/keyid.c).

(2) When Ed25519 curve is selected, it's a key for EdDSA.
    I'm not sure if current UI is good or not, but just for now
    (in g10/keygen.c).

(3) Update of OID of Ed25519 to match the ones in the
    functions openpgp_curve_to_oid and openpgp_oid_to_curve
    (in common/openpgp-oid.c).
    It will be updated again soon, but just for now .


    g10: EdDSA support.

    * g10/keyid.c (keygrip_from_pk): Compute keygrip of EdDSA key.
    * g10/keygen.c (generate_subkeypair): Ed25519 is for EdDSA.
    * common/openpgp-oid.c (oid_ed25519): Update.

OK to commit&push?

diff --git a/g10/keyid.c b/g10/keyid.c
index 9ed64a4..4ce77aa 100644
--- a/g10/keyid.c
+++ b/g10/keyid.c
@@ -813,7 +813,9 @@ keygrip_from_pk (PKT_public_key *pk, unsigned char *array)
         else
           {
             err = gcry_sexp_build (&s_pkey, NULL,
-                                   "(public-key(ecc(curve%s)(q%m)))",
+                                   pk->pubkey_algo == PUBKEY_ALGO_EDDSA ?
+                                   "(public-key(ecc(curve%s)(flags eddsa)(q%m)))"
+                                   : "(public-key(ecc(curve%s)(q%m)))", 
                                    curve, pk->pkey[1]);
             xfree (curve);
           }
diff --git a/g10/keygen.c b/g10/keygen.c
index 135699d..f3052e4 100644
--- a/g10/keygen.c
+++ b/g10/keygen.c
@@ -4031,7 +4031,11 @@ generate_subkeypair (ctrl_t ctrl, kbnode_t keyblock)
   else if (algo == PUBKEY_ALGO_ECDSA
            || algo == PUBKEY_ALGO_EDDSA
            || algo == PUBKEY_ALGO_ECDH)
-    curve = ask_curve ();
+    {
+      curve = ask_curve ();
+      if (curve && !strcmp (curve, "Ed25519"))
+        algo = PUBKEY_ALGO_EDDSA;
+    }
   else
     nbits = ask_keysize (algo, 0);
 
diff --git a/common/openpgp-oid.c b/common/openpgp-oid.c
index a2a3617..94a2296 100644
--- a/common/openpgp-oid.c
+++ b/common/openpgp-oid.c
@@ -39,7 +39,7 @@
 
 /* The OID for Curve Ed25519 in OpenPGP format.  */
 static const char oid_ed25519[] =
-  { 0x0a, 0x2b, 0x06, 0x01, 0x04, 0x01, 0x97, 0x55, 0x01, 0x05, 0x01 };
+  { 0x09, 0x2b, 0x06, 0x01, 0x04, 0x01, 0xda, 0x47, 0x0f, 0x01 };
 

 /* Helper for openpgp_oid_from_str.  */
--