1 /* ==================================================================== 2 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 3 * 4 * The Elliptic Curve Public-Key Crypto Library (ECC Code) included 5 * herein is developed by SUN MICROSYSTEMS, INC., and is contributed 6 * to the OpenSSL project. 7 * 8 * The ECC Code is licensed pursuant to the OpenSSL open source 9 * license provided below. 10 * 11 * The ECDH software is originally written by Douglas Stebila of 12 * Sun Microsystems Laboratories. 13 * 14 */ 15 /* ==================================================================== 16 * Copyright (c) 2000-2002 The OpenSSL Project. All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions 20 * are met: 21 * 22 * 1. Redistributions of source code must retain the above copyright 23 * notice, this list of conditions and the following disclaimer. 24 * 25 * 2. Redistributions in binary form must reproduce the above copyright 26 * notice, this list of conditions and the following disclaimer in 27 * the documentation and/or other materials provided with the 28 * distribution. 29 * 30 * 3. All advertising materials mentioning features or use of this 31 * software must display the following acknowledgment: 32 * "This product includes software developed by the OpenSSL Project 33 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 34 * 35 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 36 * endorse or promote products derived from this software without 37 * prior written permission. For written permission, please contact 38 * licensing@OpenSSL.org. 39 * 40 * 5. Products derived from this software may not be called "OpenSSL" 41 * nor may "OpenSSL" appear in their names without prior written 42 * permission of the OpenSSL Project. 43 * 44 * 6. Redistributions of any form whatsoever must retain the following 45 * acknowledgment: 46 * "This product includes software developed by the OpenSSL Project 47 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 50 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 52 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 53 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 54 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 55 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 56 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 58 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 59 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 60 * OF THE POSSIBILITY OF SUCH DAMAGE. 61 * ==================================================================== 62 * 63 * This product includes cryptographic software written by Eric Young 64 * (eay@cryptsoft.com). This product includes software written by Tim 65 * Hudson (tjh@cryptsoft.com). */ 66 67 #ifndef OPENSSL_HEADER_ECDH_H 68 #define OPENSSL_HEADER_ECDH_H 69 70 #include <openssl/base.h> 71 72 #include <openssl/ec_key.h> 73 74 #if defined(__cplusplus) 75 extern "C" { 76 #endif 77 78 79 // Elliptic curve Diffie-Hellman. 80 81 82 // ECDH_compute_key calculates the shared key between |pub_key| and |priv_key|. 83 // If |kdf| is not NULL, then it is called with the bytes of the shared key and 84 // the parameter |out|. When |kdf| returns, the value of |*outlen| becomes the 85 // return value. Otherwise, as many bytes of the shared key as will fit are 86 // copied directly to, at most, |outlen| bytes at |out|. It returns the number 87 // of bytes written to |out|, or -1 on error. 88 OPENSSL_EXPORT int ECDH_compute_key( 89 void *out, size_t outlen, const EC_POINT *pub_key, const EC_KEY *priv_key, 90 void *(*kdf)(const void *in, size_t inlen, void *out, size_t *outlen)); 91 92 // ECDH_compute_key_fips calculates the shared key between |pub_key| and 93 // |priv_key| and hashes it with the appropriate SHA function for |out_len|. The 94 // only value values for |out_len| are thus 24 (SHA-224), 32 (SHA-256), 48 95 // (SHA-384), and 64 (SHA-512). It returns one on success and zero on error. 96 // 97 // Note that the return value is different to |ECDH_compute_key|: it returns an 98 // error flag (as is common for BoringSSL) rather than the number of bytes 99 // written. 100 // 101 // This function allows the FIPS module to compute an ECDH and KDF within the 102 // module boundary without taking an arbitrary function pointer for the KDF, 103 // which isn't very FIPSy. 104 OPENSSL_EXPORT int ECDH_compute_key_fips(uint8_t *out, size_t out_len, 105 const EC_POINT *pub_key, 106 const EC_KEY *priv_key); 107 108 109 #if defined(__cplusplus) 110 } // extern C 111 #endif 112 113 #define ECDH_R_KDF_FAILED 100 114 #define ECDH_R_NO_PRIVATE_VALUE 101 115 #define ECDH_R_POINT_ARITHMETIC_FAILURE 102 116 #define ECDH_R_UNKNOWN_DIGEST_LENGTH 103 117 118 #endif // OPENSSL_HEADER_ECDH_H 119