I have been given a task to encrypt an xml file before sending it to a different server and use it there after decrypting it just to make the data transfer more secured.
Here is what the code does to encrypt and decrypt an xml file -
This is to be entered in the web.config file -
< system.web>
< machineKey validationKey="1B8B081B3ED61D4663AE0F85406E69A5C8D8D2B8" decryptionKey="77C3813937C1C210054267AC940D0E75A4BD988F095EDE2D"
decryption="3DES"
validation="SHA1"/>
OR
< machineKey
validationKey="AutoGenerate,IsolateApps"
decryptionKey="AutoGenerate,IsolateApps"
validation="SHA1"
decryption="Auto"
/>Now is the code -
public XmlDocument Config = new XmlDocument();
public string sEnvironment = "";
string sLoc = string.Empty;
protected void Page_Load(object sender, EventArgs e) {
sLoc = Server.MapPath("XMLFile1.xml");
Config.Load(sLoc);
sEnvironment = "Prod"; // ConfigurationSettings.AppSettings["Environment"].ToString();
if (IsXmlEncrypted(Config))
//Config = DecryptXml(Config);
DecryptXml(sLoc);
else
{
if (sEnvironment != "Local")
{
EncryptXml(sLoc, "root");
}
Config = DecryptXml(Config);
}
}
#region Encrypt and Decrypt Methods
///
/// EncryptXml is a method that will encrypt and entire Xml file, or just a particular node in an Xml. This method accepts 2 parameters: the path where the Xml file is located
/// and the node that must be encrypted. If the entire Xml document needs to be encrypted, the root node of the Xml document must be passed as the node parameter.
/// NOTE: This method SAVES the file! If you do not need to overwrite your Xml file, then DO NOT USE this method. Use the other version in its place.
/// ///
The actual path where the Xml file is stored.
///
The node from which encryption starts. If the root node is passed as a parameter, the entire document will be encrypted.
/// If you do not need the entire document encrypted, but instead, just one node, pass the node in in xpath format: "root/parent/child"
///
public void EncryptXml(string file, string node) {
sLoc = Server.MapPath("web.config");
Config.Load(sLoc);
XmlNode xNode = Config.SelectSingleNode("configuration/system.web/machineKey");
CspParameters cspParams = new CspParameters();
cspParams.KeyContainerName = xNode.Attributes["validationKey"].InnerText;
cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider(cspParams);
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.Load(file);
XmlElement elementToEncrypt = xmlDoc.GetElementsByTagName(node)[0] as XmlElement;
if (elementToEncrypt != null)
{
RijndaelManaged sessionKey = new RijndaelManaged();
sessionKey.KeySize = 256;
EncryptedXml eXml = new EncryptedXml();
byte[] encryptedElement = eXml.EncryptData(elementToEncrypt, sessionKey, false);
EncryptedData eData = new EncryptedData();
eData.Type = EncryptedXml.XmlEncElementUrl;
eData.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncAES256Url);
EncryptedKey eKey = new EncryptedKey();
byte[] encryptedKey = EncryptedXml.EncryptKey(sessionKey.Key, rsaKey, false);
eKey.CipherData = new CipherData(encryptedKey);
eKey.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncRSA15Url);
eData.KeyInfo = new KeyInfo();
KeyInfoName kin = new KeyInfoName();
kin.Value = xNode.Attributes["decryptionKey"].InnerText;
eKey.KeyInfo.AddClause(kin);
eData.KeyInfo.AddClause(new KeyInfoEncryptedKey(eKey));
eData.CipherData.CipherValue = encryptedElement;
EncryptedXml.ReplaceElement(elementToEncrypt, eData, false);
xmlDoc.Save(file);
}
else
throw new ArgumentNullException("The specified node does not exist in the provided Xml document.");
}
///
/// EncryptXml is a method that will encrypt an Xml file and return an XmlDocument object for use IN MEMORY. If the XmlDocument needs to be saved, then it is up to the calling
/// program to save the encrypted Xml file.
/// ///
A previously loaded Xml file that needs to be encrypted.
///
he node from which encryption starts. If the root node is passed as a parameter, the entire document will be encrypted.
/// If you do not need the entire document encrypted, but instead, just one node, pass the node in in xpath format: "root/parent/child"
///
///
An encrypted XmlDocument. How it is used is up to the calling program. public static XmlDocument EncryptXml(XmlDocument xmlDoc, string node) {
XmlDocument xmlDocToEncrypt = xmlDoc;
XmlDocument config = DotNetNuke.Common.Utilities.Config.Load();
XmlNode xNode = config.SelectSingleNode("configuration/system.web/machineKey");
CspParameters cspParams = new CspParameters();
cspParams.KeyContainerName = xNode.Attributes["validationKey"].InnerText;
cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider(cspParams);
XmlElement elementToEncrypt = xmlDocToEncrypt.GetElementsByTagName(node)[0] as XmlElement;
if (elementToEncrypt != null)
{
RijndaelManaged sessionKey = new RijndaelManaged();
sessionKey.KeySize = 256;
EncryptedXml eXml = new EncryptedXml();
byte[] encryptedElement = eXml.EncryptData(elementToEncrypt, sessionKey, false);
EncryptedData eData = new EncryptedData();
eData.Type = EncryptedXml.XmlEncElementUrl;
eData.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncAES256Url);
EncryptedKey eKey = new EncryptedKey();
byte[] encryptedKey = EncryptedXml.EncryptKey(sessionKey.Key, rsaKey, false);
eKey.CipherData = new CipherData(encryptedKey);
eKey.EncryptionMethod = new EncryptionMethod(EncryptedXml.XmlEncRSA15Url);
eData.KeyInfo = new KeyInfo();
KeyInfoName kin = new KeyInfoName();
kin.Value = xNode.Attributes["decryptionKey"].InnerText;
eKey.KeyInfo.AddClause(kin);
eData.KeyInfo.AddClause(new KeyInfoEncryptedKey(eKey));
eData.CipherData.CipherValue = encryptedElement;
EncryptedXml.ReplaceElement(elementToEncrypt, eData, false);
return xmlDocToEncrypt;
}
else
throw new ArgumentNullException("The specified Xml node does not exist in the provided Xml document.");
}
///
/// This method encrypts a string!
/// ///
The string that needs to be encrypted.
///
The encrypted string. public static string EncryptData(string data) {
DotNetNuke.Security.PortalSecurity ps = new PortalSecurity();
XmlDocument config = DotNetNuke.Common.Utilities.Config.Load();
XmlNode node = config.SelectSingleNode("configuration/system.web/machineKey");
return ps.Encrypt(node.Attributes["decryptionKey"].InnerText, data);
}
///
/// This method decrypts a previously encrypted string!
/// ///
The string that needs to be decrypted.
///
The decrypted string. public static string DecryptData(string data) {
DotNetNuke.Security.PortalSecurity ps = new PortalSecurity();
XmlDocument config = DotNetNuke.Common.Utilities.Config.Load();
XmlNode node = config.SelectSingleNode("configuration/system.web/machineKey");
return ps.Decrypt(node.Attributes["decryptionKey"].InnerText, data);
}
///
/// DecryptXml decrypts an Xml file. This method will decrypt the file and then save it to the specified location. If you
/// do not want your original file overwritten, then do not use this method.
/// ///
The path of the encrypted Xml file.
public void DecryptXml(string file) {
sLoc = Server.MapPath("web.config");
Config.Load(sLoc);
XmlNode xNode = Config.SelectSingleNode("configuration/system.web/machineKey");
CspParameters cspParams = new CspParameters();
cspParams.KeyContainerName = xNode.Attributes["validationKey"].InnerText;
cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider(cspParams);
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.Load(file);
EncryptedXml eXml = new EncryptedXml(xmlDoc);
eXml.AddKeyNameMapping(xNode.Attributes["decryptionKey"].InnerText, rsaKey);
eXml.DecryptDocument();
try
{
xmlDoc.Save(file);
}
catch (XmlException ex)
{
DotNetNuke.Services.Exceptions.Exceptions.LogException(ex);
}
}
///
/// This version of DecryptXml will decrypt a given Xml file for use in memory. If the file needs to be saved, it is up to the calling program to handle that.
/// ///
The encrypted Xml document that must be decrypted
///
The node within the document that is to be decrypted
public XmlDocument DecryptXml(XmlDocument xDoc) {
sLoc = Server.MapPath("web.config");
Config.Load(sLoc);
XmlNode xNode = Config.SelectSingleNode("configuration/system.web/machineKey");
XmlDocument xmlDoc = xDoc;
CspParameters cspParams = new CspParameters();
cspParams.KeyContainerName = xNode.Attributes["validationKey"].InnerText;
cspParams.Flags = CspProviderFlags.UseMachineKeyStore;
RSACryptoServiceProvider rsaKey = new RSACryptoServiceProvider(cspParams);
EncryptedXml eXml = new EncryptedXml(xmlDoc);
eXml.AddKeyNameMapping(xNode.Attributes["decryptionKey"].InnerText, rsaKey);
eXml.DecryptDocument();
return xmlDoc;
}
///
/// This method will determine if the "EncryptedData" node exists. If so, then this file has been encrypted.
/// ///
The xml file to test for encryption.
///
TRUE OR FALSE public static bool IsXmlEncrypted(XmlDocument xDoc) {
XmlElement eData = xDoc.GetElementsByTagName("EncryptedData")[0] as XmlElement;
if (eData != null)
return true;
else
return false;
}
