static bool WriteCredential (string targetName, string userName, string password)
{
if (targetName == null)
throw new ArgumentNullException ("targetName");
if (userName == null)
throw new ArgumentNullException ("userName");
if (password == null)
throw new ArgumentNullException ("password");
var passwordBytes = Encoding.Unicode.GetBytes (password);
if (passwordBytes.Length > 512)
throw new ArgumentException ("The secret message has exceeded 512 bytes.");
// Go ahead with what we have are stuff it into the CredMan structures.
var cred = new Credential {
TargetName = targetName,
CredentialBlob = password,
CredentialBlobSize = (UInt32) passwordBytes.Length,
AttributeCount = 0,
Attributes = IntPtr.Zero,
Comment = null,
TargetAlias = null,
Type = NativeCredentialType.Generic,
Persist = PersistFlags.LocalMachine,
UserName = userName,
};
var ncred = NativeCredential.GetNativeCredential (cred);
// Write the info into the CredMan storage.
var didWrite = NativeMethods.CredWrite (ref ncred, 0);
Marshal.FreeCoTaskMem (ncred.TargetName);
Marshal.FreeCoTaskMem (ncred.CredentialBlob);
Marshal.FreeCoTaskMem (ncred.UserName);
return didWrite;
}
/// <summary>
/// This method derives a NativeCredential instance from a given Credential instance.
/// </summary>
/// <param name="cred">The managed Credential counterpart containing data to be stored.</param>
/// <returns>A NativeCredential instance that is derived from the given Credential
/// instance.</returns>
internal static NativeCredential GetNativeCredential (Credential cred)
{
return new NativeCredential {
AttributeCount = 0,
Attributes = IntPtr.Zero,
Comment = IntPtr.Zero,
TargetAlias = IntPtr.Zero,
Type = NativeCredentialType.Generic,
Persist = (UInt32)PersistFlags.LocalMachine,
CredentialBlobSize = cred.CredentialBlobSize,
TargetName = Marshal.StringToCoTaskMemUni (cred.TargetName),
CredentialBlob = Marshal.StringToCoTaskMemUni (cred.CredentialBlob),
UserName = Marshal.StringToCoTaskMemUni (cred.UserName)
};
}
