CAS Update

CRP/CRP.csproj

@@ -200,6 +200,7 @@
     <Compile Include="Controllers\ExcelController.cs" />
     <Compile Include="Controllers\FIDController.cs" />
     <Compile Include="Controllers\HelpController.cs" />
+    <Compile Include="Controllers\Helpers\CASHelper.cs" />
     <Compile Include="Controllers\Helpers\Filter\PageTrackingAttribute.cs" />
     <Compile Include="Controllers\Helpers\ServiceMessages.cs" />
     <Compile Include="Controllers\Helpers\StringExtension.cs" />

CRP/Controllers/AccountController.cs

@@ -9,7 +9,6 @@
 using MvcContrib.Attributes;
 using CRP.Core.Resources;
 using UCDArch.Core.PersistanceSupport;
-using UCDArch.Web.Authentication;
 using UCDArch.Web.Controller;
 using MvcContrib;
 using UCDArch.Web.Validator;

CRP/Controllers/Helpers/CASHelper.cs

@@ -0,0 +1,108 @@
+using System;
+using System.IO;
+using System.Net;
+using System.Web;
+using System.Web.Security;
+
+namespace CRP.Controllers.Helpers
+{
+    public static class CASHelper
+    {
+        private const string StrCasUrl = "https://cas.ucdavis.edu/cas/";
+        private const string StrTicket = "ticket";
+        private const string StrReturnUrl = "ReturnURL";
+
+        public static string GetReturnUrl()
+        {
+            return HttpContext.Current.Request.QueryString[StrReturnUrl];
+        }
+
+        /// <summary>
+        /// Performs the CAS Login and automatically redirects to the desired page, if possible.
+        /// Will do nothing if the user is already authenticated
+        /// </summary>
+        public static void LoginAndRedirect()
+        {
+            string returnUrl = Login();
+
+            if (returnUrl != null) HttpContext.Current.Response.Redirect(returnUrl);
+        }
+
+        /// <summary>
+        /// Login to the campus DistAuth system using CAS
+        /// </summary>
+        public static string Login()
+        {
+            // get the context from the source
+            var context = HttpContext.Current;
+
+            // try to load a valid ticket
+            HttpCookie validCookie = context.Request.Cookies[FormsAuthentication.FormsCookieName];
+            FormsAuthenticationTicket validTicket = null;
+
+            // check to make sure cookie is valid by trying to decrypt it
+            if (validCookie != null)
+            {
+                try
+                {
+                    validTicket = FormsAuthentication.Decrypt(validCookie.Value);
+                }
+                catch
+                {
+                    validTicket = null;
+                }
+            }
+
+            // if user is unauthorized and no validTicket is defined then authenticate with cas
+            //if (context.Response.StatusCode == 0x191 && (validTicket == null || validTicket.Expired))
+            if (validTicket == null || validTicket.Expired)
+            {
+                // build query string but strip out ticket if it is defined
+                string query = "";
+                foreach (string key in context.Request.QueryString.AllKeys)
+                {
+                    if (string.Compare(key, StrTicket, true) != 0)
+                    {
+                        query += "&" + key + "=" + context.Request.QueryString[key];
+                    }
+                }
+
+                // replace 1st character with ? if query is not empty
+                if (!string.IsNullOrEmpty(query))
+                {
+                    query = "?" + query.Substring(1);
+                }
+
+                // get ticket & service
+                string ticket = context.Request.QueryString[StrTicket];
+                string service = context.Server.UrlEncode(context.Request.Url.GetLeftPart(UriPartial.Path) + query);
+
+                // if ticket is defined then we assume they are coming from CAS
+                if (!string.IsNullOrEmpty(ticket))
+                {
+                    // validate ticket against cas
+                    StreamReader sr = new StreamReader(new WebClient().OpenRead(StrCasUrl + "validate?ticket=" + ticket + "&service=" + service));
+
+                    // parse text file
+                    if (sr.ReadLine() == "yes")
+                    {
+                        // get kerberos id
+                        string kerberos = sr.ReadLine();
+
+                        // set forms authentication ticket
+                        FormsAuthentication.SetAuthCookie(kerberos, false);
+
+                        string returnUrl = GetReturnUrl();
+
+                        return !string.IsNullOrEmpty(returnUrl) ? returnUrl : FormsAuthentication.DefaultUrl;
+                    }
+                }
+
+                // ticket doesn't exist or is invalid so redirect user to CAS login
+                context.Response.Redirect(StrCasUrl + "login?service=" + service);
+            }
+
+            return null;
+        }
+    }
+}