Add GOST DSA according to GOST R 34.10-2001/-2012

Add GOST Digital Signature Algorithms support according to GOST R
34.10-2001/-2012. English translations of these standards are provided
as RFC 5832 and RFC 7091.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/ecc-hash.c b/ecc-hash.c
index 4e830a51..07877110 100644
--- a/ecc-hash.c
+++ b/ecc-hash.c
@@ -62,3 +62,14 @@ ecc_hash (const struct ecc_modulo *m,
     /* We got a few extra bits, at the low end. Discard them. */
     mpn_rshift (hp, hp, m->size + 1, 8*length - m->bit_size);
 }
+
+void
+gost_hash (const struct ecc_modulo *m,
+	   mp_limb_t *hp,
+	   size_t length, const uint8_t *digest)
+{
+  if (length > ((size_t) m->bit_size + 7) / 8)
+    length = (m->bit_size + 7) / 8;
+
+  mpn_set_base256_le (hp, m->size + 1, digest, length);
+}