Add Ed25519 support (#91)

* Add support for Ed25519 as a public key type

Ed25519 is a elliptic curve signature scheme that offers
better security than ECDSA and DSA and good performance. It may be
used for both user and host keys.

OpenSSH key import and fuzzer are not supported yet.

Initially inspired by Peter Szabo.

* Add curve25519 and ed25519 fuzzers

* Add import and export of Ed25519 keys

1 files changed, 22 insertions, 49 deletions

diff --git a/LICENSE b/LICENSE
index c400d94..a4849ff 100644
--- a/LICENSE
+++ b/LICENSE
@@ -90,52 +90,25 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 =====
 
-curve25519-donna:
-
-/* Copyright 2008, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * curve25519-donna: Curve25519 elliptic curve, public key function
- *
- * http://code.google.com/p/curve25519-donna/
- *
- * Adam Langley <agl@imperialviolet.org>
- *
- * Derived from public domain C code by Daniel J. Bernstein <djb@cr.yp.to>
- *
- * More information about curve25519 can be found here
- *   http://cr.yp.to/ecdh.html
- *
- * djb's sample implementation of curve25519 is written in a special assembly
- * language called qhasm and uses the floating point registers.
- *
- * This is, almost, a clean room reimplementation from the curve25519 paper. It
- * uses many of the tricks described therein. Only the crecip function is taken
- * from the sample implementation.
- */
+crypto25519.c:
+crypto26619.h:
+
+Modified TweetNaCl version 20140427, a self-contained public-domain C library.
+https://tweetnacl.cr.yp.to/
+
+Contributors (alphabetical order)
+Daniel J. Bernstein, University of Illinois at Chicago and Technische
+Universiteit Eindhoven
+Bernard van Gastel, Radboud Universiteit Nijmegen
+Wesley Janssen, Radboud Universiteit Nijmegen
+Tanja Lange, Technische Universiteit Eindhoven
+Peter Schwabe, Radboud Universiteit Nijmegen
+Sjaak Smetsers, Radboud Universiteit Nijmegen
+
+Acknowledgments
+This work was supported by the U.S. National Science Foundation under grant
+1018836. "Any opinions, findings, and conclusions or recommendations expressed
+in this material are those of the author(s) and do not necessarily reflect the
+views of the National Science Foundation."
+This work was supported by the Netherlands Organisation for Scientific
+Research (NWO) under grant 639.073.005 and Veni 2013 project 13114.