--- /dev/null
+/* -*-c-*-
+ *
+ * The Ed448 signature scheme
+ *
+ * (c) 2017 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of secnet.
+ * See README for full list of copyright holders.
+ *
+ * secnet is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version d of the License, or
+ * (at your option) any later version.
+ *
+ * secnet is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 3 along with secnet; if not, see
+ * https://www.gnu.org/licenses/gpl.html.
+ *
+ * This file was originally part of Catacomb, but has been automatically
+ * modified for incorporation into secnet: see `import-catacomb-crypto'
+ * for details.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Notes on the Ed448 signature scheme -------------------------------*
+ *
+ * This is Ed448, as described in RFC8032, using the EdDSA signature scheme
+ * defined by Daniel J. Bernstein, Neils Duif, Simon Josefsson, Tanja Lange,
+ * Peter Schwabe, and Bo-Yin Yang, `High-speed high-security signatures',
+ * CHES 2011, https://ed25519.cr.yp.to/ed25519-20110926.pdf and `EdDSA for
+ * more curves', http://ed25519.cr.yp.to/eddsa-20150704.pdf.
+ *
+ * This is not the signature scheme described in Hamburg's paper
+ * `Ed448-Goldilocks, a new elliptic curve', EUROCRYPT 2016,
+ * https://eprint.iacr.org/2015/625/, which (a) made use of his `Decaf'
+ * cofactor elimination technique, and (b) was based on Schnorr rather than
+ * EdDSA.
+ *
+ * This code implements the `Ed448' and `Ed448ph' schemes described in
+ * RFC8032, though in the latter case it assumes that you've already done the
+ * hashing and have provided the hash as the `message' input.
+ */
+
+#ifndef CATACOMB_ED448_H
+#define CATACOMB_ED448_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/*----- Header files ------------------------------------------------------*/
+
+#include "fake-mLib-bits.h"
+
+/*----- Important constants -----------------------------------------------*/
+
+#define ED448_KEYSZ 57u
+#define ED448_PUBSZ 57u
+#define ED448_SIGSZ 114u
+
+#define ED448_MAXPERSOSZ 255u
+
+/*----- Functions provided ------------------------------------------------*/
+
+/* --- @ed448_pubkey@ --- *
+ *
+ * Arguments: @octet K[ED448_PUBSZ]@ = where to put the public key
+ * @const void *k@ = private key
+ * @size_t ksz@ = length of private key
+ *
+ * Returns: ---
+ *
+ * Use: Derives the public key from a private key.
+ */
+
+extern void ed448_pubkey(octet /*K*/[ED448_PUBSZ],
+ const void */*k*/, size_t /*ksz*/);
+
+/* --- @ed448_sign@ --- *
+ *
+ * Arguments: @octet sig[ED448_SIGSZ]@ = where to put the signature
+ * @const void *k@ = private key
+ * @size_t ksz@ = length of private key
+ * @const octet K[ED448_PUBSZ]@ = public key
+ * @int phflag@ = whether the `message' has been hashed already
+ * @const void *p@ = personalization string
+ * @size_t psz@ = length of personalization string
+ * @const void *m@ = message to sign
+ * @size_t msz@ = length of message
+ *
+ * Returns: ---
+ *
+ * Use: Signs a message.
+ */
+
+extern void ed448_sign(octet /*sig*/[ED448_SIGSZ],
+ const void */*k*/, size_t /*ksz*/,
+ const octet /*K*/[ED448_PUBSZ],
+ int /*phflag*/, const void */*p*/, size_t /*psz*/,
+ const void */*m*/, size_t /*msz*/);
+
+/* --- @ed448_verify@ --- *
+ *
+ * Arguments: @const octet K[ED448_PUBSZ]@ = public key
+ * @const void *m@ = message to sign
+ * @int phflag@ = whether the `message' has been hashed already
+ * @const void *p@ = personalization string
+ * @size_t psz@ = length of personalization string
+ * @size_t msz@ = length of message
+ * @const octet sig[ED448_SIGSZ]@ = signature
+ *
+ * Returns: Zero if OK, negative on failure.
+ *
+ * Use: Verify a signature.
+ */
+
+extern int ed448_verify(const octet /*K*/[ED448_PUBSZ],
+ int /*phflag*/, const void */*p*/, size_t /*psz*/,
+ const void */*m*/, size_t /*msz*/,
+ const octet /*sig*/[ED448_SIGSZ]);
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif
~mdw / secnet / blobdiff