private async void UnprotectAsyncBuffer_Click(object sender, RoutedEventArgs e)
{
string outputStr = "";
string plainMessage = "";
try
{
if (m_protectedBuffer != null)
{
BufferProtectUnprotectResult unBuffer = await DataProtectionManager.UnprotectAsync(m_protectedBuffer);
m_unprotectedBuffer = unBuffer.Buffer;
plainMessage = CryptographicBuffer.ConvertBinaryToString(BinaryStringEncoding.Utf8,
m_unprotectedBuffer
);
outputStr += "\n Status: " + unBuffer.ProtectionInfo.Status;
outputStr += "\n Unprotected string:" + plainMessage;
rootPage.NotifyUser(outputStr, NotifyType.StatusMessage);
}
else
{
rootPage.NotifyUser("Please protect a buffer to unprotect", NotifyType.ErrorMessage);
}
}
catch (Exception ex)
{
rootPage.NotifyUser(outputStr + "\n" + ex.ToString(), NotifyType.ErrorMessage);
}
}
private async void DoBufferWork(IBackgroundTaskInstance taskInstance)
{
string message = "Hello World!";
string unprotectedMessage = "";
string logFileName = "Bufferlog.txt";
string logFileContent = "";
StorageFolder localFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
StorageFile logFile = await localFolder.CreateFileAsync(logFileName, CreationCollisionOption.OpenIfExists);
IBuffer inputBuffer = CryptographicBuffer.ConvertStringToBinary(message, BinaryStringEncoding.Utf8);
BufferProtectUnprotectResult procBuffer = await DataProtectionManager.ProtectAsync(inputBuffer, m_EnterpriseID);
logFileContent += "\r\n" + DateTime.Now + ":" + "ProtStatus:" + procBuffer.ProtectionInfo.Status + "\n";
logFileContent += "\r\n" + "Protected Buffer:" + CryptographicBuffer.EncodeToHexString(procBuffer.Buffer).Substring(0, 5);
// If keys are dropped under lock, unprotectBuffer will fail so don't unprotectbuffer under lock
if (!m_areKeysDropped)
{
BufferProtectUnprotectResult unBuffer = await DataProtectionManager.UnprotectAsync(procBuffer.Buffer);
unprotectedMessage = CryptographicBuffer.ConvertBinaryToString(BinaryStringEncoding.Utf8, procBuffer.Buffer);
logFileContent += "\n Unprotected string:" + unprotectedMessage;
if (message != unprotectedMessage)
{
throw new Exception("Original string does not match with unprotectedMessage!");
}
}
await FileIO.AppendTextAsync(logFile, logFileContent);
}
private async void ProtectedAccessSuspending(object sender, ProtectedAccessSuspendingEventArgs args)
{
string logFileContent = "";
Windows.Foundation.Deferral deferal = args.GetDeferral();
// Protect any sensitive data in Memory so that it cannot be accessed while the device is locked
// You should encrypt or destory any copies of sensitve data while device is going to a locked state.
IBuffer inputBuffer = CryptographicBuffer.ConvertStringToBinary(m_SecretMessage,
BinaryStringEncoding.Utf8);
BufferProtectUnprotectResult procBuffer = await DataProtectionManager.ProtectAsync(inputBuffer, m_EnterpriseID);
m_protectedBuffer = procBuffer.Buffer;
deferal.Complete();
m_areKeysDropped = true;
var settings = ApplicationData.Current.LocalSettings;
settings.Values[m_taskName] += "\nApp got DPL suspend event";
StorageFolder localFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
StorageFile logFile = await localFolder.CreateFileAsync("SuspendLog.txt",
CreationCollisionOption.OpenIfExists);
logFileContent += "\r\n" + DateTime.Now + ":" + "Got DPL Protected Suspended";
logFileContent += "\r\n" + "Protection Status:" + procBuffer.ProtectionInfo.Status;
await FileIO.AppendTextAsync(logFile, logFileContent);
}
private async void ProtectedAccessResumed(object sender, ProtectedAccessResumedEventArgs args)
{
string logFileContent = "";
// Keys are available so can read and write from a protected file
m_areKeysDropped = false;
//
BufferProtectUnprotectResult unBuffer = await DataProtectionManager.UnprotectAsync(m_protectedBuffer);
m_SecretMessage = CryptographicBuffer.ConvertBinaryToString(BinaryStringEncoding.Utf8,
m_protectedBuffer
);
logFileContent += "\n Unprotected string:" + m_SecretMessage;
var settings = ApplicationData.Current.LocalSettings;
settings.Values[m_taskName] += "\nApp got DPL resumed event";
StorageFolder localFolder =
Windows.Storage.ApplicationData.Current.LocalFolder;
StorageFile logFile = await localFolder.CreateFileAsync("ResumeLog.txt",
CreationCollisionOption.OpenIfExists);
await FileIO.AppendTextAsync(logFile, "\r\n" + DateTime.Now + ":" + "Got DPL Protected resumed");
}
private async void ProtectAsyncBuffer_Click(object sender, RoutedEventArgs e)
{
string outputStr = "\n Protecting string:" + m_protectedMessage;
IBuffer inputBuffer = CryptographicBuffer.ConvertStringToBinary(m_protectedMessage,
BinaryStringEncoding.Utf8);
BufferProtectUnprotectResult procBuffer = await DataProtectionManager.ProtectAsync(inputBuffer, Scenario1.m_enterpriseId);
m_protectedBuffer = procBuffer.Buffer;
outputStr += "\n Status: " + procBuffer.ProtectionInfo.Status;
outputStr += "\n Protected string:";
outputStr += CryptographicBuffer.EncodeToHexString(m_protectedBuffer).Substring(0, 20);
rootPage.NotifyUser(outputStr, NotifyType.StatusMessage);
}
