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Diffstat (limited to 'libressl/include/openssl/curve25519.h')
-rw-r--r-- | libressl/include/openssl/curve25519.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/libressl/include/openssl/curve25519.h b/libressl/include/openssl/curve25519.h new file mode 100644 index 00000000..5aaa8c08 --- /dev/null +++ b/libressl/include/openssl/curve25519.h @@ -0,0 +1,67 @@ +/* + * Copyright (c) 2015, Google Inc. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY + * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION + * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN + * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifndef HEADER_CURVE25519_H +#define HEADER_CURVE25519_H + +#include <stdint.h> + +#include <openssl/opensslconf.h> + +#if defined(__cplusplus) +extern "C" { +#endif + +/* + * Curve25519. + * + * Curve25519 is an elliptic curve. See https://tools.ietf.org/html/rfc7748. + */ + +/* + * X25519. + * + * X25519 is the Diffie-Hellman primitive built from curve25519. It is + * sometimes referred to as curve25519, but X25519 is a more precise name. + * See http://cr.yp.to/ecdh.html and https://tools.ietf.org/html/rfc7748. + */ + +#define X25519_KEY_LENGTH 32 + +/* + * X25519_keypair sets |out_public_value| and |out_private_key| to a freshly + * generated, public/private key pair. + */ +void X25519_keypair(uint8_t out_public_value[X25519_KEY_LENGTH], + uint8_t out_private_key[X25519_KEY_LENGTH]); + +/* + * X25519 writes a shared key to |out_shared_key| that is calculated from the + * given private key and the peer's public value. It returns one on success and + * zero on error. + * + * Don't use the shared key directly, rather use a KDF and also include the two + * public values as inputs. + */ +int X25519(uint8_t out_shared_key[X25519_KEY_LENGTH], + const uint8_t private_key[X25519_KEY_LENGTH], + const uint8_t peers_public_value[X25519_KEY_LENGTH]); + +#if defined(__cplusplus) +} /* extern C */ +#endif + +#endif /* HEADER_CURVE25519_H */ |