1 /* Copyright (c) 2015, Google Inc. 2 * 3 * Permission to use, copy, modify, and/or distribute this software for any 4 * purpose with or without fee is hereby granted, provided that the above 5 * copyright notice and this permission notice appear in all copies. 6 * 7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 14 15 #ifndef OPENSSL_HEADER_CURVE25519_H 16 #define OPENSSL_HEADER_CURVE25519_H 17 18 #include <openssl/base.h> 19 20 #if defined(__cplusplus) 21 extern "C" { 22 #endif 23 24 25 /* Curve25519. 26 * 27 * Curve25519 is an elliptic curve. See 28 * https://tools.ietf.org/html/draft-irtf-cfrg-curves-11. */ 29 30 31 /* X25519. 32 * 33 * Curve25519 is an elliptic curve. The same name is also sometimes used for 34 * the Diffie-Hellman primitive built from it but X25519 is a more precise 35 * name for that, which is the one used here. See http://cr.yp.to/ecdh.html and 36 * https://tools.ietf.org/html/draft-irtf-cfrg-curves-11. */ 37 38 /* X25519_keypair sets |out_public_value| and |out_private_key| to a freshly 39 * generated, publicprivate key pair. */ 40 OPENSSL_EXPORT void X25519_keypair(uint8_t out_public_value[32], 41 uint8_t out_private_key[32]); 42 43 /* X25519 writes a shared key to |out_shared_key| that is calculated from the 44 * given private key and the peer's public value. It returns one on success and 45 * zero on error. 46 * 47 * Don't use the shared key directly, rather use a KDF and also include the two 48 * public values as inputs. */ 49 OPENSSL_EXPORT int X25519(uint8_t out_shared_key[32], 50 const uint8_t private_key[32], 51 const uint8_t peers_public_value[32]); 52 53 /* X25519_public_from_private calculates a Diffie-Hellman public value from the 54 * given private key and writes it to |out_public_value|. */ 55 OPENSSL_EXPORT void X25519_public_from_private(uint8_t out_public_value[32], 56 const uint8_t private_key[32]); 57 58 59 /* Ed25519. 60 * 61 * Ed25519 is a signature scheme using a twisted-Edwards curve that is 62 * birationally equivalent to curve25519. */ 63 64 #define ED25519_PRIVATE_KEY_LEN 64 65 #define ED25519_PUBLIC_KEY_LEN 32 66 #define ED25519_SIGNATURE_LEN 64 67 68 /* ED25519_keypair sets |out_public_key| and |out_private_key| to a freshly 69 * generated, publicprivate key pair. */ 70 OPENSSL_EXPORT void ED25519_keypair(uint8_t out_public_key[32], 71 uint8_t out_private_key[64]); 72 73 /* ED25519_sign sets |out_sig| to be a signature of |message_len| bytes from 74 * |message| using |private_key|. It returns one on success or zero on 75 * error. */ 76 OPENSSL_EXPORT int ED25519_sign(uint8_t out_sig[64], const uint8_t *message, 77 size_t message_len, 78 const uint8_t private_key[64]); 79 80 /* ED25519_verify returns one iff |signature| is a valid signature, by 81 * |public_key| of |message_len| bytes from |message|. It returns zero 82 * otherwise. */ 83 OPENSSL_EXPORT int ED25519_verify(const uint8_t *message, size_t message_len, 84 const uint8_t signature[64], 85 const uint8_t public_key[32]); 86 87 88 #if defined(__cplusplus) 89 } /* extern C */ 90 #endif 91 92 #endif /* OPENSSL_HEADER_CURVE25519_H */ 93
