diff options
Diffstat (limited to 'crypto/ecdh/ech_ossl.c')
| -rw-r--r-- | crypto/ecdh/ech_ossl.c | 57 |
1 files changed, 44 insertions, 13 deletions
diff --git a/crypto/ecdh/ech_ossl.c b/crypto/ecdh/ech_ossl.c index 182e825b74..b3cff5ad90 100644 --- a/crypto/ecdh/ech_ossl.c +++ b/crypto/ecdh/ech_ossl.c @@ -14,7 +14,7 @@ * */ /* ==================================================================== - * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. + * Copyright (c) 1998-2003 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 @@ -68,12 +68,18 @@ */ -#include "ecdh.h" +#include <string.h> +#include <limits.h> + +#include "cryptlib.h" + +#include <openssl/ecdh.h> #include <openssl/err.h> #include <openssl/sha.h> #include <openssl/obj_mac.h> -static int ecdh_compute_key(unsigned char *key, const EC_POINT *pub_key, EC_KEY *ecdh); +static int ecdh_compute_key(void *out, size_t len, const EC_POINT *pub_key, EC_KEY *ecdh, + void *(*KDF)(void *in, size_t inlen, void *out, size_t outlen)); static ECDH_METHOD openssl_ecdh_meth = { "OpenSSL ECDH method", @@ -95,16 +101,23 @@ const ECDH_METHOD *ECDH_OpenSSL(void) /* This implementation is based on the following primitives in the IEEE 1363 standard: * - ECKAS-DH1 * - ECSVDP-DH - * - KDF1 with SHA-1 + * Finally an optional KDF is applied. */ -static int ecdh_compute_key(unsigned char *key, const EC_POINT *pub_key, EC_KEY *ecdh) +static int ecdh_compute_key(void *out, size_t outlen, const EC_POINT *pub_key, EC_KEY *ecdh, + void *(*KDF)(void *in, size_t inlen, void *out, size_t outlen)) { BN_CTX *ctx; EC_POINT *tmp=NULL; BIGNUM *x=NULL, *y=NULL; - int ret= -1, len; + int ret= -1, buflen, len; unsigned char *buf=NULL; + if (outlen > INT_MAX) + { + ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ERR_R_MALLOC_FAILURE); /* sort of, anyway */ + return -1; + } + if ((ctx = BN_CTX_new()) == NULL) goto err; BN_CTX_start(ctx); x = BN_CTX_get(ctx); @@ -145,26 +158,44 @@ static int ecdh_compute_key(unsigned char *key, const EC_POINT *pub_key, EC_KEY } } - if ((buf = (unsigned char *)OPENSSL_malloc(sizeof(unsigned char) * BN_num_bytes(x))) == NULL) + buflen = (EC_GROUP_get_degree(ecdh->group) + 7)/8; + len = BN_num_bytes(x); + if (len > buflen) + { + ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ERR_R_INTERNAL_ERROR); + goto err; + } + if ((buf = OPENSSL_malloc(buflen)) == NULL) { ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ERR_R_MALLOC_FAILURE); goto err; } - if ((len = BN_bn2bin(x,buf)) <= 0) + memset(buf, 0, buflen - len); + if (len != BN_bn2bin(x, buf + buflen - len)) { ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ERR_R_BN_LIB); goto err; } - if ((SHA1(buf, len, key) == NULL)) + if (KDF != 0) { - ECDHerr(ECDH_F_ECDH_COMPUTE_KEY,ECDH_R_SHA1_DIGEST_FAILED); - goto err; + if (KDF(buf, buflen, out, outlen) == NULL) + { + ECDHerr(ECDH_F_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; } - ret = 20; - err: if (tmp) EC_POINT_free(tmp); if (ctx) BN_CTX_end(ctx); |