Started to try and organize all the authentication code.

SecureCore/Services/UserDataService.cs

@@ -33,6 +33,25 @@ namespace SecureCore.Services
             }
         }
 
+        public static bool UserHasLoginData(string userName)
+        {
+            var userId = GetUserId(userName);
+
+            using (var connection = new SqlConnection(ConnectionString))
+            {
+                using (var command = new SqlCommand("SELECT [Password Hash], [Salt Hash] FROM Login WHERE [User Key] = @UserId", connection))
+                {
+                    command.Parameters.AddWithValue("UserId", userId);
+
+                    connection.Open();
+
+                    var reader = command.ExecuteReader();
+
+                    return reader.HasRows;
+                }
+            }
+        }
+
         public static int GetUserId(string userName)
         {
             using (var connection = new SqlConnection(ConnectionString))
@@ -121,5 +140,20 @@ namespace SecureCore.Services
                 }
             }
         }
+
+        public static void DestorySession(string sessionToken)
+        {
+            using (var connection = new SqlConnection(ConnectionString))
+            {
+                using (var command = new SqlCommand("DELETE FROM [Session] WHERE [Session Token] = @SessionToken", connection))
+                {
+                    command.Parameters.AddWithValue("SessionToken", sessionToken);
+
+                    connection.Open();
+
+                    command.ExecuteNonQuery();
+                }
+            }
+        }
     }
 }