private static bool PromptForCredentials(Uri targetUri, out string username, out string password)
{
NativeMethods.CredentialUiInfo credUiInfo = new NativeMethods.CredentialUiInfo
{
BannerArt = IntPtr.Zero,
CaptionText = Title,
MessageText = String.Format("Enter you credentials for {0}://{1}.", targetUri.Scheme, targetUri.DnsSafeHost),
Parent = IntPtr.Zero,
Size = Marshal.SizeOf(typeof(NativeMethods.CredentialUiInfo))
};
bool saveCredentials = false;
NativeMethods.CredentialPackFlags authPackage = NativeMethods.CredentialPackFlags.None;
IntPtr packedAuthBufferPtr = IntPtr.Zero;
uint packedAuthBufferSize = 0;
NativeMethods.CredentialUiWindowsFlags flags = NativeMethods.CredentialUiWindowsFlags.Generic;
try
{
int result;
if ((result = NativeMethods.CredUIPromptForWindowsCredentials(ref credUiInfo,
0,
ref authPackage,
IntPtr.Zero,
0,
out packedAuthBufferPtr,
out packedAuthBufferSize,
ref saveCredentials,
flags)) != NativeMethods.Win32Error.Success)
{
username = null;
password = null;
return false;
}
StringBuilder usernameBuffer = new StringBuilder(512);
StringBuilder domainBuffer = new StringBuilder(256);
StringBuilder passwordBuffer = new StringBuilder(512);
int usernameLen = usernameBuffer.Capacity;
int passwordLen = passwordBuffer.Capacity;
int domainLen = domainBuffer.Capacity;
if (!NativeMethods.CredUnPackAuthenticationBuffer(authPackage,
packedAuthBufferPtr,
packedAuthBufferSize,
usernameBuffer,
ref usernameLen,
domainBuffer,
ref domainLen,
passwordBuffer,
ref passwordLen))
{
username = null;
password = null;
return false;
}
username = usernameBuffer.ToString();
password = passwordBuffer.ToString();
return true;
}
catch { throw; }
finally
{
if (packedAuthBufferPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(packedAuthBufferPtr);
}
}
}
private static bool ModalPromptForCredentials(Uri targetUri, string message, out string username, out string password)
{
Debug.Assert(targetUri != null);
Debug.Assert(message != null);
Trace.WriteLine("Program::ModalPromptForCredemtials");
NativeMethods.CredentialUiInfo credUiInfo = new NativeMethods.CredentialUiInfo
{
BannerArt = IntPtr.Zero,
CaptionText = Title,
MessageText = message,
Parent = IntPtr.Zero,
Size = Marshal.SizeOf(typeof(NativeMethods.CredentialUiInfo))
};
NativeMethods.CredentialUiWindowsFlags flags = NativeMethods.CredentialUiWindowsFlags.Generic;
NativeMethods.CredentialPackFlags authPackage = NativeMethods.CredentialPackFlags.None;
IntPtr packedAuthBufferPtr = IntPtr.Zero;
IntPtr inBufferPtr = IntPtr.Zero;
uint packedAuthBufferSize = 0;
bool saveCredentials = false;
int inBufferSize = 0;
return ModalPromptDisplayDialog(ref credUiInfo,
ref authPackage,
packedAuthBufferPtr,
packedAuthBufferSize,
inBufferPtr,
inBufferSize,
saveCredentials,
flags,
out username,
out password);
}
private static bool ModalPromptForPassword(Uri targetUri, string message, string username, out string password)
{
Debug.Assert(targetUri != null);
Debug.Assert(message != null);
Debug.Assert(username != null);
Trace.WriteLine("Program::ModalPromptForPassword");
NativeMethods.CredentialUiInfo credUiInfo = new NativeMethods.CredentialUiInfo
{
BannerArt = IntPtr.Zero,
CaptionText = Title,
MessageText = message,
Parent = IntPtr.Zero,
Size = Marshal.SizeOf(typeof(NativeMethods.CredentialUiInfo))
};
NativeMethods.CredentialUiWindowsFlags flags = NativeMethods.CredentialUiWindowsFlags.Generic;
NativeMethods.CredentialPackFlags authPackage = NativeMethods.CredentialPackFlags.None;
IntPtr packedAuthBufferPtr = IntPtr.Zero;
IntPtr inBufferPtr = IntPtr.Zero;
uint packedAuthBufferSize = 0;
bool saveCredentials = false;
int inBufferSize = 0;
try
{
int error;
// execute with `null` to determine buffer size
// always returns false when determining size, only fail if `inBufferSize` looks bad
NativeMethods.CredPackAuthenticationBuffer(flags: authPackage,
username: username,
password: String.Empty,
packedCredentials: inBufferPtr,
packedCredentialsSize: ref inBufferSize);
if (inBufferSize <= 0)
{
error = Marshal.GetLastWin32Error();
Trace.WriteLine(" unable to determine credential buffer size (" + NativeMethods.Win32Error.GetText(error) + ").");
username = null;
password = null;
return false;
}
inBufferPtr = Marshal.AllocHGlobal(inBufferSize);
if (!NativeMethods.CredPackAuthenticationBuffer(flags: authPackage,
username: username,
password: String.Empty,
packedCredentials: inBufferPtr,
packedCredentialsSize: ref inBufferSize))
{
error = Marshal.GetLastWin32Error();
Trace.WriteLine(" unable to write to credential buffer (" + NativeMethods.Win32Error.GetText(error) + ").");
username = null;
password = null;
return false;
}
return ModalPromptDisplayDialog(ref credUiInfo,
ref authPackage,
packedAuthBufferPtr,
packedAuthBufferSize,
inBufferPtr,
inBufferSize,
saveCredentials,
flags,
out username,
out password);
}
finally
{
if (inBufferPtr != IntPtr.Zero)
{
Marshal.FreeCoTaskMem(inBufferPtr);
}
}
}
private static bool PromptForCredentialsBase( Uri targetUri, out string username, out string password, string message, string displayUsername = "") {
Debug.Assert(targetUri != null);
Trace.WriteLine("Program::PromptForCredentials");
NativeMethods.CredentialUiInfo credUiInfo = new NativeMethods.CredentialUiInfo
{
BannerArt = IntPtr.Zero,
CaptionText = Title,
MessageText = message,
Parent = IntPtr.Zero,
Size = Marshal.SizeOf(typeof(NativeMethods.CredentialUiInfo))
};
bool saveCredentials = false;
NativeMethods.CredentialPackFlags authPackage = NativeMethods.CredentialPackFlags.None;
IntPtr inBufferPtr = IntPtr.Zero;
int inBufferSize = 0;
if ( !string.IsNullOrEmpty( displayUsername ) ) {
// Execute with ZeroPtr to determine buffer size
NativeMethods.CredPackAuthenticationBuffer( authPackage, displayUsername, "", inBufferPtr, ref inBufferSize );
inBufferPtr = Marshal.AllocCoTaskMem( inBufferSize );
NativeMethods.CredPackAuthenticationBuffer( authPackage, displayUsername, "", inBufferPtr, ref inBufferSize );
}
IntPtr packedAuthBufferPtr = IntPtr.Zero;
uint packedAuthBufferSize = 0;
NativeMethods.CredentialUiWindowsFlags flags = NativeMethods.CredentialUiWindowsFlags.Generic;
try
{
// open a standard Windows authentication dialog to acquire username + password credentials
int error;
if ((error = NativeMethods.CredUIPromptForWindowsCredentials(ref credUiInfo,
0,
ref authPackage,
inBufferPtr,
(uint)inBufferSize,
out packedAuthBufferPtr,
out packedAuthBufferSize,
ref saveCredentials,
flags)) != NativeMethods.Win32Error.Success)
{
username = null;
password = null;
Trace.WriteLine(" credential prompt failed (" + NativeMethods.Win32Error.GetText(error) + ").");
return false;
}
// use `StringBuilder` references instead of string so that they can be written to
StringBuilder usernameBuffer = new StringBuilder(512);
StringBuilder domainBuffer = new StringBuilder(256);
StringBuilder passwordBuffer = new StringBuilder(512);
int usernameLen = usernameBuffer.Capacity;
int passwordLen = passwordBuffer.Capacity;
int domainLen = domainBuffer.Capacity;
// unpack the result into locally useful data
if (!NativeMethods.CredUnPackAuthenticationBuffer(authPackage,
packedAuthBufferPtr,
packedAuthBufferSize,
usernameBuffer,
ref usernameLen,
domainBuffer,
ref domainLen,
passwordBuffer,
ref passwordLen))
{
username = null;
password = null;
error = Marshal.GetLastWin32Error();
Trace.WriteLine(" failed to unpack buffer (" + NativeMethods.Win32Error.GetText(error) + ").");
return false;
}
username = usernameBuffer.ToString();
password = passwordBuffer.ToString();
return true;
}
catch { throw; }
finally
{
if (packedAuthBufferPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(packedAuthBufferPtr);
}
if (inBufferPtr != IntPtr.Zero)
{
Marshal.FreeCoTaskMem( inBufferPtr );
}
}
}
