diff options
Diffstat (limited to 'src/crypto/ecdh/ecdh.c')
| -rw-r--r-- | src/crypto/ecdh/ecdh.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/src/crypto/ecdh/ecdh.c b/src/crypto/ecdh/ecdh.c new file mode 100644 index 0000000..d4497f1 --- /dev/null +++ b/src/crypto/ecdh/ecdh.c @@ -0,0 +1,157 @@ +/* ==================================================================== + * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. + * + * The Elliptic Curve Public-Key Crypto Library (ECC Code) included + * herein is developed by SUN MICROSYSTEMS, INC., and is contributed + * to the OpenSSL project. + * + * The ECC Code is licensed pursuant to the OpenSSL open source + * license provided below. + * + * The ECDH software is originally written by Douglas Stebila of + * Sun Microsystems Laboratories. + * + */ +/* ==================================================================== + * Copyright (c) 2000-2002 The OpenSSL Project. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. 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. + * + * 3. All advertising materials mentioning features or use of this + * software must display the following acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * licensing@OpenSSL.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED 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 OpenSSL PROJECT OR + * ITS 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. + * ==================================================================== + * + * This product includes cryptographic software written by Eric Young + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). */ + +#include <openssl/ecdh.h> + +#include <string.h> + +#include <openssl/bn.h> +#include <openssl/digest.h> +#include <openssl/err.h> +#include <openssl/mem.h> + + +int ECDH_compute_key(void *out, size_t outlen, const EC_POINT *pub_key, + EC_KEY *priv_key, void *(*KDF)(const void *in, size_t inlen, + void *out, size_t *outlen)) { + BN_CTX *ctx; + EC_POINT *tmp = NULL; + BIGNUM *x = NULL, *y = NULL; + const BIGNUM *priv; + const EC_GROUP *group; + int ret = -1; + size_t buflen; + uint8_t *buf = NULL; + + if ((ctx = BN_CTX_new()) == NULL) { + goto err; + } + BN_CTX_start(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + + priv = EC_KEY_get0_private_key(priv_key); + if (priv == NULL) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ECDH_R_NO_PRIVATE_VALUE); + goto err; + } + + group = EC_KEY_get0_group(priv_key); + + tmp = EC_POINT_new(group); + if (tmp == NULL) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ERR_R_MALLOC_FAILURE); + goto err; + } + + if (!EC_POINT_mul(group, tmp, NULL, pub_key, priv, ctx)) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ECDH_R_POINT_ARITHMETIC_FAILURE); + goto err; + } + + if (!EC_POINT_get_affine_coordinates_GFp(group, tmp, x, y, ctx)) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ECDH_R_POINT_ARITHMETIC_FAILURE); + goto err; + } + + buflen = (EC_GROUP_get_degree(group) + 7) / 8; + buf = OPENSSL_malloc(buflen); + if (buf == NULL) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ERR_R_MALLOC_FAILURE); + goto err; + } + + if (!BN_bn2bin_padded(buf, buflen, x)) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ERR_R_INTERNAL_ERROR); + goto err; + } + + if (KDF != 0) { + if (KDF(buf, buflen, out, &outlen) == NULL) { + OPENSSL_PUT_ERROR(ECDH, ECDH_compute_key, ECDH_R_KDF_FAILED); + goto err; + } + ret = outlen; + } else { + /* no KDF, just copy as much as we can */ + if (outlen > buflen) { + outlen = buflen; + } + memcpy(out, buf, outlen); + ret = outlen; + } + +err: + if (tmp) + EC_POINT_free(tmp); + if (ctx) + BN_CTX_end(ctx); + if (ctx) + BN_CTX_free(ctx); + if (buf) + OPENSSL_free(buf); + return ret; +} |