CRYPTO_EX_INDEX_DH
if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_DH,
if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data))
CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, l, p, newf, dupf, freef)