diff options
| -rw-r--r-- | g10/ecdh.c | 31 |
1 files changed, 14 insertions, 17 deletions
diff --git a/g10/ecdh.c b/g10/ecdh.c index c3337d1dc..d676e2c19 100644 --- a/g10/ecdh.c +++ b/g10/ecdh.c @@ -189,25 +189,22 @@ derive_kek (size_t kek_size, const unsigned char *kdf_params, size_t kdf_params_size) { gpg_error_t err; - gcry_md_hd_t h; - - log_assert( gcry_md_get_algo_dlen (kdf_hash_algo) >= 32 ); - - err = gcry_md_open (&h, kdf_hash_algo, 0); - if (err) + gcry_kdf_hd_t hd; + unsigned long param[1]; + + param[0] = kek_size; + err = gcry_kdf_open (&hd, GCRY_KDF_ONESTEP_KDF, kdf_hash_algo, + param, 1, + secret_x, secret_x_size, NULL, 0, NULL, 0, + kdf_params, kdf_params_size); + if (!err) { - log_error ("gcry_md_open failed for kdf_hash_algo %d: %s", - kdf_hash_algo, gpg_strerror (err)); - return err; + gcry_kdf_compute (hd, NULL); + gcry_kdf_final (hd, kek_size, secret_x); + gcry_kdf_close (hd); + /* Clean the tail before returning. */ + memset (secret_x+kek_size, 0, secret_x_size - kek_size); } - gcry_md_write(h, "\x00\x00\x00\x01", 4); /* counter = 1 */ - gcry_md_write(h, secret_x, secret_x_size); /* x of the point X */ - gcry_md_write(h, kdf_params, kdf_params_size); /* KDF parameters */ - gcry_md_final (h); - memcpy (secret_x, gcry_md_read (h, kdf_hash_algo), kek_size); - gcry_md_close (h); - /* Clean the tail before returning. */ - memset (secret_x+kek_size, 0, secret_x_size - kek_size); if (DBG_CRYPTO) log_printhex (secret_x, kek_size, "ecdh KEK is:"); return err; |