CRYPTO_EX_INDEX_DH
CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp, new_func,