EVP_PKEY_get1_DH
DH *EVP_PKEY_get1_DH(const EVP_PKEY *pkey);
LCRYPTO_ALIAS(EVP_PKEY_get1_DH);
LCRYPTO_USED(EVP_PKEY_get1_DH);
if ((dh_a = EVP_PKEY_get1_DH(pkey)) == NULL) {