EVP_PKEY_get0_DH
DH *EVP_PKEY_get0_DH(const EVP_PKEY *pkey);
LCRYPTO_ALIAS(EVP_PKEY_get0_DH);
if ((dh = EVP_PKEY_get0_DH(pkey)) == NULL)
LCRYPTO_USED(EVP_PKEY_get0_DH);
if (BN_cmp(DH_get0_pub_key(EVP_PKEY_get0_DH(pkey_a)),
DH_get0_pub_key(EVP_PKEY_get0_DH(pkey_b))) != 0) {