diff --git a/common/openpgp-misc.c b/common/openpgp-misc.c
new file mode 100644
index 000000000..7c6c56a69
--- /dev/null
+++ b/common/openpgp-misc.c
@@ -0,0 +1,61 @@
+#include <config.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <assert.h>
+
+#include "util.h"
+#include "openpgpdefs.h"
+
+gcry_mpi_t
+openpgp_ecc_parse_pubkey (pubkey_algo_t pkalgo, const char *curve_oid,
+			  gcry_mpi_t pubkey)
+{
+  unsigned int nbits = 0;
+  unsigned char *buf = NULL;
+  const char *curve = openpgp_oid_to_curve (curve_oid, 1);
+
+  if (curve == NULL)
+    curve = curve_oid;
+
+  if ((pkalgo == PUBKEY_ALGO_EDDSA && !strcmp (curve, "Ed448"))
+      || (pkalgo == PUBKEY_ALGO_ECDH && !strcmp (curve, "X448")))
+    buf = gcry_mpi_get_opaque (pubkey, &nbits);
+
+  if (nbits == 0
+      || (pkalgo == PUBKEY_ALGO_EDDSA && (nbits+7)/8 == (448 + 8)/8)
+      || (pkalgo == PUBKEY_ALGO_ECDH && (nbits+7)/8 == 448/8))
+    return gcry_mpi_copy (pubkey);
+
+  if (pkalgo == PUBKEY_ALGO_EDDSA)
+    return gcry_mpi_set_opaque_copy (NULL, buf+1, 8 + 448);
+  else
+    return gcry_mpi_set_opaque_copy (NULL, buf+1, 448);
+}
+
+
+gcry_mpi_t
+openpgp_ecc_parse_seckey (pubkey_algo_t pkalgo, const char *curve_oid,
+			  gcry_mpi_t seckey)
+{
+  unsigned int nbits = 0;
+  unsigned char *buf = NULL;
+  const char *curve = openpgp_oid_to_curve (curve_oid, 1);
+
+  if (curve == NULL)
+    curve = curve_oid;
+
+  if ((pkalgo == PUBKEY_ALGO_EDDSA && !strcmp (curve, "Ed448"))
+      || (pkalgo == PUBKEY_ALGO_ECDH && !strcmp (curve, "X448")))
+    buf = gcry_mpi_get_opaque (seckey, &nbits);
+
+  if (nbits == 0
+      || (pkalgo == PUBKEY_ALGO_EDDSA && (nbits+7)/8 == (448 + 8)/8)
+      || (pkalgo == PUBKEY_ALGO_ECDH && (nbits+7)/8 == 448/8))
+    return gcry_mpi_copy (seckey);
+
+  if (pkalgo == PUBKEY_ALGO_EDDSA)
+    return gcry_mpi_set_opaque_copy (NULL, buf+1, 8 + 448);
+  else
+    return gcry_mpi_set_opaque_copy (NULL, buf+1, 448);
+}