How to use the node-opcua-crypto.privateDecrypt_long function in node-opcua-crypto

function RSAOAEP_Decrypt(buffer, privateKey) {
    const block_size = crypto_utils.rsa_length(privateKey);
    return crypto_utils.privateDecrypt_long(buffer, privateKey, block_size, crypto_utils.RSA_PKCS1_OAEP_PADDING);
}
// --------------------

function RSAOAEP_Decrypt(buffer: Buffer, privateKey: PrivateKeyPEM): Buffer {
    const blockSize = rsa_length(privateKey);
    return privateDecrypt_long(buffer, privateKey, blockSize, RSA_PKCS1_OAEP_PADDING);
}

function RSAPKCS1V15_Decrypt(buffer: Buffer, privateKey: PrivateKeyPEM): Buffer {
    const blockSize = rsa_length(privateKey);
    return privateDecrypt_long(buffer, privateKey, blockSize, RSA_PKCS1_PADDING);
}

function RSAPKCS1V15_Decrypt(buffer, privateKey) {
    const block_size = crypto_utils.rsa_length(privateKey);
    return crypto_utils.privateDecrypt_long(buffer, privateKey, block_size, crypto_utils.RSA_PKCS1_PADDING);
}
function RSAOAEP_Decrypt(buffer, privateKey) {