Moved the credential files into their own folder.

Credentials/Credential.cs

@@ -0,0 +1,165 @@
+using System;
+using System.Collections.Generic;
+using System.DirectoryServices.AccountManagement;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace NSspi
+{
+    public class Credential : IDisposable
+    {
+        private bool disposed;
+
+        private SecurityPackage securityPackage;
+
+        private long credHandle;
+        private long expiry;
+
+        public Credential(SecurityPackage package, CredentialType credentialType)
+        {
+            this.disposed = false;
+            this.securityPackage = package;
+
+            this.credHandle = 0;
+            this.expiry = 0;
+
+            Init( package, credentialType );
+        }
+
+        private void Init( SecurityPackage package, CredentialType credentialType )
+        {
+            string packageName;
+            CredentialUse use;
+
+            // -- Package --
+            if ( package == SecurityPackage.Kerberos )
+            {
+                packageName = PackageNames.Kerberos;
+            }
+            else if ( package == NSspi.SecurityPackage.Negotiate )
+            {
+                packageName = PackageNames.Negotiate;
+            }
+            else if ( package == NSspi.SecurityPackage.NTLM )
+            {
+                packageName = PackageNames.Ntlm;
+            }
+            else
+            {
+                throw new ArgumentException( "Invalid value provided for the 'package' parameter." );
+            }
+
+            // -- Credential --
+            if ( credentialType == CredentialType.Client )
+            {
+                use = CredentialUse.Outbound;
+            }
+            else if ( credentialType == CredentialType.Server )
+            {
+                use = CredentialUse.Inbound;
+            }
+            else
+            {
+                throw new ArgumentException( "Invalid value provided for the 'credentialType' parameter." );
+            }
+
+            // -- Invoke --
+            SecurityStatus status = NativeMethods.AcquireCredentialsHandle(
+                null,
+                packageName,
+                use,
+                IntPtr.Zero,
+                IntPtr.Zero,
+                IntPtr.Zero,
+                IntPtr.Zero,
+                ref this.credHandle,
+                ref this.expiry
+            );
+
+            if ( status != SecurityStatus.Success )
+            {
+                throw new SSPIException( "Failed to call AcquireCredentialHandle", status );
+            }
+        }
+
+        ~Credential()
+        {
+            Dispose( false );
+        }
+
+        public SecurityPackage SecurityPackage
+        {
+            get
+            {
+                if( this.disposed )
+                {
+                    throw new ObjectDisposedException( base.GetType().Name );
+                }
+
+                return this.securityPackage;
+            }
+        }
+
+        public string Name 
+        {
+            get
+            {
+                NativeMethods.QueryNameAttribCarrier carrier = new NativeMethods.QueryNameAttribCarrier();
+
+                SecurityStatus status;
+                string name = null;
+
+                status = NativeMethods.QueryCredentialsAttribute_Name(
+                    ref this.credHandle,
+                    CredentialQueryAttrib.Names,
+                    ref carrier
+                );
+
+                if ( status == SecurityStatus.Success )
+                {
+                    name = Marshal.PtrToStringUni( carrier.Name );
+                    NativeMethods.FreeContextBuffer( carrier.Name );
+                }
+                else
+                {
+                    throw new SSPIException( "Failed to query credential name", status );
+                }
+
+                return name;
+            }
+        }
+
+        public long CredentialHandle
+        {
+            get
+            {
+                return this.credHandle;
+            }
+        }
+
+        public void Dispose()
+        {
+            Dispose( true );
+            GC.SuppressFinalize( this );
+        }
+
+        protected virtual void Dispose( bool disposing )
+        {
+            if ( this.disposed == false )
+            {
+                SecurityStatus result;
+
+                result = NativeMethods.FreeCredentialsHandle( ref this.credHandle );
+
+                this.disposed = true;
+
+                if ( disposing && result != SecurityStatus.Success )
+                {
+                    throw new SSPIException( "Failed to release credentials handle", result );
+                }
+            }
+        }
+    }
+}