Change mojo demo apps to use Application.
[chromium-blink-merge.git] / crypto / curve25519.h
blobba24c92a8778e55911f426c19b43f98a27a9f775
1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef CRYPTO_CURVE25519_H
6 #define CRYPTO_CURVE25519_H
8 #include "base/basictypes.h"
9 #include "crypto/crypto_export.h"
11 namespace crypto {
13 // Curve25519 implements the elliptic curve group known as Curve25519, as
14 // described in "Curve 25519: new Diffie-Hellman Speed Records",
15 // by D.J. Bernstein. Additional information is available at
16 // http://cr.yp.to/ecdh.html.
17 namespace curve25519 {
19 // kBytes is the number of bytes in the result of the Diffie-Hellman operation,
20 // which is an element of GF(2^255-19).
21 static const size_t kBytes = 32;
23 // kScalarBytes is the number of bytes in an element of the scalar field:
24 // GF(2^252 + 27742317777372353535851937790883648493).
25 static const size_t kScalarBytes = 32;
27 // ScalarMult computes the |shared_key| from |private_key| and
28 // |peer_public_key|. This method is a wrapper for |curve25519_donna()|. It
29 // calls that function with |private_key| as |secret| and |peer_public_key| as
30 // basepoint. |private_key| should be of length |kScalarBytes| and
31 // |peer_public_key| should be of length |kBytes|.
32 // See "Computing shared secrets" section of/ http://cr.yp.to/ecdh.html.
33 CRYPTO_EXPORT void ScalarMult(const uint8* private_key,
34 const uint8* peer_public_key,
35 uint8* shared_key);
37 // ScalarBaseMult computes the |public_key| from |private_key|. This method is a
38 // wrapper for |curve25519_donna()|. It calls that function with |private_key|
39 // as |secret| and |kBasePoint| as basepoint. |private_key| should be of length
40 // |kScalarBytes|. See "Computing public keys" section of
41 // http://cr.yp.to/ecdh.html.
42 CRYPTO_EXPORT void ScalarBaseMult(const uint8* private_key, uint8* public_key);
44 } // namespace curve25519
46 } // namespace crypto
48 #endif // CRYPTO_CURVE25519_H