Steps To Deface A Webpage

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First of all, I do not deface, I never have (besides friends sites as jokes and all in good fun), and never will. So how do I know how to deface? I guess I just picked it up on the way, so I am no expert in this. If I get a thing or two wrong I apoligize. It is pretty simple when you think that defacing is just replacing a file on a computer. Now, finding the exploit in the first place, that takes skill, that takes knowledge, that is what real hackers are made of. I don't encourage that you deface any sites, as this can be used get credit cards, get passwords, get source code, billing info, email databases, etc.. (it is only right to put up some kind of warning. now go have fun ;)

This tutorial will be broken down into 3 main sections, they are as followed:
1. Finding Vuln Hosts.

2. Getting In.
3. Covering Your Tracks

It really is easy, and I will show you how easy it is.

1. Finding Vuln Hosts

This section needs to be further broken down into two catigories of script kiddies: ones who scan the net for a host that is vuln to a certain exploit and ones who search a certain site for any exploit. The ones you see on alldas are the first kind, they scan thousands of sites for a specific exploit. They do not care who they hack, anyone will do. They have no set target and not much of a purpose. In my opinion these people should either have a cause behind what they are doing, ie. "I make sure people keep up to date with security, I am a messanger" or "I am spreading a political message, I use defacments to get media attention". People who deface to get famous or to show off their skills need to grow up and relize there is a better way of going about this (not that I support the ones with other reasons ether). Anyways, the two kinds and what you need to know about them:

Scanning Script Kiddie: You need to know what signs of the hole are, is it a service? A certain OS? A CGI file? How can you tell if they are vuln? What version(s) are vuln? You need to know how to search the net to find targets which are running whatever is vuln. Use altavista.com or google.com for web based exploits. Using a script to scan ip ranges for a certain port that runs the vuln service. Or using netcraft.com to find out what kind of server they are running and what extras it runs (frontpage, php, etc..) nmap and other port scanners allow quick scans of thousands of ips for open ports. This is a favorate technique of those guys you see with mass hacks on alldas.

Targetted Site Script Kiddie: More respectable then the script kiddies who hack any old site. The main step here is gathering as much information about a site as possible. Find out what OS they run at netcraft or by using: telnet www.site.com 80 then GET / HTTP/1.1 Find out what services they run by doing a port scan. Find out the specifics on the services by telnetting to them. Find any cgi script, or other files which could allow access to the server if exploited by checking /cgi /cgi-bin and browsing around the site (remember to index browse)
Wasn't so hard to get the info was it? It may take awhile, but go through the site slowly and get all the information you can.

2. Getting In

Now that we got the info on the site we can find the exploit(s) we can use to get access. If you were a scanning script kiddie you would know the exploit ahead of time. A couple of great places to look for exploits are Security Focus and packetstorm. Once you get the exploit check and make sure that the exploit is for the same version as the service, OS, script, etc.. Exploits mainly come in two languages, the most used are C and perl. Perl scripts will end in .pl or .cgi, while C will end in .c To compile a C file (on *nix systems) do gcc -o exploit12 file.c then: ./exploit12 For perl just do: chmod 700 file.pl (not really needed) then: perl file.pl. If it is not a script it might be a very simple exploit, or just a theory of a possible exploit. Just do alittle research into how to use it. Another thing you need to check is weither the exploit is remote or local. If it is local you must have an account or physical access to the computer. If it is remote you can do it over a network (internet).

Don't go compiling exploits just yet, there is one more important thing you need to know
Covering Your Tracks

So by now you have gotten the info on the host inorder to find an exploit that will allow you to get access.

So why not do it? The problem with covering your tracks isn't that it is hard, rather that it is unpredictable. just because you killed the sys logging doesn't mean that they don't have another logger or IDS running somewhere else. (even on another box). Since most script kiddies don't know the skill of the admin they are targetting they have no way of knowing if they have additional loggers or what. Instead the script kiddie makes it very hard (next to impossible) for the admin to track them down. Many use a stolden or second isp account to begin with, so even if they get tracked they won't get caught. If you don't have the luxery of this then you MUST use multiple wingates, shell accounts, or trojans to bounce off of. Linking them together will make it very hard for someone to track you down. Logs on the wingates and shells will most likely be erased after like 2-7 days. That is if logs are kept at all. It is hard enough to even get ahold of one admin in a week, let alone further tracking the script kiddie down to the next wingate or shell and then getting ahold of that admin all before the logs of any are erased. And it is rare for an admin to even notice an attack, even a smaller percent will actively pursue the attacker at all and will just secure their box and forget it ever happend. For the sake of arugment lets just say if you use wingates and shells, don't do anything to piss the admin off too much (which will get them to call authoritizes or try to track you down) and you deleting logs you will be safe. So how do you do it?
We will keep this very short and too the point, so we'll need to get a few wingates. Wingates by nature tend to change IPs or shutdown all the time, so you need an updated list or program to scan the net for them. You can get a list of wingates that is well updated at http://www.cyberarmy.com/lists/wingate/ and you can also get a program called winscan there. Now lets say we have 3 wingates:

212.96.195.33 port 23
202.134.244.215 port 1080
203.87.131.9 port 23
to use them we go to telnet and connect to them on port 23. we should get a responce like this:
CSM Proxy Server >
to connect to the next wingate we just type in it's ip:port
CSM Proxy Server >202.134.244.215:1080

If you get an error it is most likely to be that the proxy you are trying to connect to isn't up, or that you need to login to the proxy. If all goes well you will get the 3 chained together and have a shell account you are able to connect to. Once you are in your shell account you can link shells together by:
[j00@server j00]$ ssh 212.23.53.74

You can get free shells to work with until you get some hacked shells, here is a list of free shell accounts. And please remember to sign up with false information and from a wingate if possible.
SDF (freeshell.org) - http://sdf.lonestar.org
GREX (cyberspace.org) - http://www.grex.org
NYX - http://www.nxy.net
ShellYeah - http://www.shellyeah.org
HOBBITON.org - http://www.hobbiton.org
FreeShells - http://www.freeshells.net
DucTape - http://www.ductape.net
Free.Net.Pl (Polish server) - http://www.free.net.pl
XOX.pl (Polish server) - http://www.xox.pl
IProtection - http://www.iprotection.com
CORONUS - http://www.coronus.com
ODD.org - http://www.odd.org
MARMOSET - http://www.marmoset.net
flame.org - http://www.flame.org
freeshells - http://freeshells.net.pk
LinuxShell - http://www.linuxshell.org
takiweb - http://www.takiweb.com
FreePort - http://freeport.xenos.net
BSDSHELL - http://free.bsdshell.net
ROOTshell.be - http://www.rootshell.be
shellasylum.com - http://www.shellasylum.com
Daforest - http://www.daforest.org
FreedomShell.com - http://www.freedomshell.com
LuxAdmin - http://www.luxadmin.org
shellweb - http://shellweb.net
blekko - http://blekko.net

once you get on your last shell you can compile the exploit, and you should be safe from being tracked. But lets be even more sure and delete the evidence that we were there.

Alright, there are a few things on the server side that all script kiddies need to be aware of. Mostly these are logs that you must delete or edit. The real script kiddies might even use a rootkit to automaticly delete the logs. Although lets assume you aren't that lame. There are two main logging daemons which I will cover, klogd which is the kernel logs, and syslogd which is the system logs. First step is to kill the daemons so they don't log anymore of your actions.

[root@hacked root]# ps -def | grep syslogd
[root@hacked root]# kill -9 pid_of_syslogd
in the first line we are finding the pid of the syslogd, in the second we are killing the daemon. You can also use /etc/syslog.pid to find the pid of syslogd.
[root@hacked root]# ps -def | grep klogd
[root@hacked root]# kill -9 pid_of_klogd
Same thing happening here with klogd as we did with syslogd.

now that killed the default loggers the script kiddie needs to delete themself from the logs. To find where syslogd puts it's logs check the /etc/syslog.conf file. Of course if you don't care if the admin knows you were there you can delete the logs completely. Lets say you are the lamest of the script kiddies, a defacer, the admin would know that the box has been comprimised since the website was defaced. So there is no point in appending the logs, they would just delete them. The reason we are appending them is so that the admin will not even know a break in has accurd. I'll go over the main reasons people break into a box:

To deface the website. - this is really lame, since it has no point and just damages the system.
To sniff for other network passwords. - there are programs which allow you to sniff other passwords sent from and to the box. If this box is on an ethernet network then you can even sniff packets (which contain passwords) that are destine to any box in that segment.
To mount a DDoS attack. - another lame reason, the admin has a high chance of noticing that you comprimised him once you start sending hundreds of MBs through his connection.
To mount another attack on a box. - this and sniffing is the most commonly used, not lame, reason for exploiting something. Since you now how a rootshell you can mount your attack from this box instead of those crappy freeshells. And you now have control over the logging of the shell.

To get sensitive info. - some corperate boxes have alot of valueable info on them. Credit card databases, source code for software, user/password lists, and other top secret info that a hacker may want to have.
To learn and have fun. - many people do it for the thrill of hacking, and the knowledge you gain. I don't see this as horrible a crime as defacing. as long as you don't destroy anything I don't think this is very bad. Infact some people will even help the admin patch the hole. Still illegal though, and best not to break into anyone's box.

I'll go over the basic log files: utmp, wtmp, lastlog, and .bash_history
These files are usually in /var/log/ but I have heard of them being in /etc/ /usr/bin/ and other places. Since it is different on alot of boxes it is best to just do a find / -iname 'utmp'|find / -iname 'wtmp'|find / -iname 'lastlog'. and also search threw the /usr/ /var/ and /etc/ directories for other logs. Now for the explanation of these 3.

utmp is the log file for who is on the system, I think you can see why this log should be appended. Because you do not want to let anyone know you are in the system. wtmp logs the logins and logouts as well as other info you want to keep away from the admin. Should be appended to show that you never logged in or out. and lastlog is a file which keeps records of all logins. Your shell's history is another file that keeps a log of all the commands you issued, you should look for it in your $ HOME directory and edit it, .sh_history, .history, and .bash_history are the common names. you should only append these log files, not delete them. if you delete them it will be like holding a big sign infront of the admin saying "You've been hacked". Newbie script kiddies often deface and then rm -rf / to be safe. I would avoid this unless you are really freaking out. In this case I would suggest that you never try to exploit a box again. Another way to find log files is to run a script to check for open files (and then manually look at them to determine if they are logs) or do a find for files which have been editted, this command would be: find / -ctime 0 -print

A few popular scripts which can hide your presence from logs include: zap, clear and cloak. Zap will replace your presence in the logs with 0's, clear will clear the logs of your presence, and cloak will replace your presence with different information. acct-cleaner is the only heavily used script in deleting account logging from my experience. Most rootkits have a log cleaning script, and once you installed it logs are not kept of you anyways. If you are on NT the logs are at C:\winNT\system32\LogFiles\, just delete them, nt admins most likely don't check them or don't know what it means if they are deleted.
One final thing about covering your tracks, I won't go to into detail about this because it would require a tutorial all to itself. I am talking about rootkits. What are rootkits? They are a very widely used tool used to cover your tracks once you get into a box. They will make staying hidden painfree and very easy. What they do is replace the binaries like login, ps, and who to not show your presence, ever. They will allow you to login without a password, without being logged by wtmp or lastlog and without even being in the /etc/passwd file. They also make commands like ps not show your processes, so no one knows what programs you are running. They send out fake reports on netstat, ls, and w so that everything looks the way it normally would, except anything you do is missing. But there are some flaws in rootkits, for one some commands produce strange effects because the binary was not made correctly. They also leave fingerprints (ways to tell that the file is from a rootkit). Only smart/good admins check for rootkits, so this isn't the biggest threat, but it should be concidered. Rootkits that come with a LKM (loadable kernel module) are usually the best as they can pretty much make you totally invisible to all others and most admins wouldn't be able to tell they were comprimised.

In writting this tutorial I have mixed feelings. I do not want more script kiddies out their scanning

hundreds of sites for the next exploit. And I don't want my name on any shouts. I rather would like to have people say "mmm, that defacing crap is pretty lame" especially when people with no lives scan for exploits everyday just to get their name on a site for a few minutes. I feel alot of people are learning everything but what they need to know inorder to break into boxes. Maybe this tutorial cut to the chase alittle and helps people with some knowledge see how simple it is and hopefully make them see that getting into a system is not all it's hyped up to be. It is not by any means a full guide, I did not cover alot of things. I hope admins found this tutorial helpful aswell, learning that no matter what site you run you should always keep on top of the latest exploits and patch them. Protect yourself with IDS and try finding holes on your own system (both with vuln scanners and by hand). Also setting up an external box to log is not a bad idea. Admins should have also seen alittle bit into the mind of a script kiddie and learned a few things he does.. this should help you catch one if they break into your systems.

On one final note, defacing is lame. I know many people who have defaced in the past and regret it now. You will be labeled a script kiddie and a lamer for a long, long time.

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Consuming Membership and Profile Services via ASP.NET AJAX

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ASP.NET 2.0 introduced various application services—such as Membership, Roles, and Profiles—that eliminate a lot of coding that was required to provide the same functionality. However, these services are part of ASP.NET's server-side framework, which could pose a challenge when you use ASP.NET AJAX to consume the services from client-side JavaScript code. Fortunately, ASP.NET AJAX provides an out-of-the-box solution to this problem. This article explains how to use this solution in C# with Visual Studio.

Sample Scenario

Suppose you are developing a new web site and want to implement forms authentication. The web site will have a user registration page, a login page, and one or more pages that you must secure. The user registration and login pages use ASP.NET AJAX for an enhanced user experience. Also, the site must capture details such as birth date and address at the time of registration. This information is to be stored in the Profile of the user.

To develop a web site that fulfills all the above requirements, begin by creating a new ASP.NET AJAX-enabled web site with C# (see Figure 1).

Figure 1. Creating a New ASP.NET AJAX-enabled Web Site

Configuring the Web Site

Before you begin coding, configure the web site for forms authentication as well as Membership and Profile services. Open a web.config file in your Visual Studio IDE and add the following markup inside the connectionStrings section:

<connectionStrings>

   <add name="connstr"

        connectionString="data source=.\sqlexpress;

        initial catalog=northwind;

        integrated security=true"

        providerName="System.Data.SqlClient"/>

</connectionStrings>

You specified a database connection string named connstr that points to a Northwind database. Make sure to change the connection string to match your development environment. I assume that your database is configured for application services using the aspnet_regsql.exe tool. You will use this connection string while configuring membership and profile providers.

Now, add the following markup inside the system.web section:

<system.web>

<authentication mode="Forms">

   <forms loginUrl="Login.aspx"></forms>

</authentication>

<authorization>

   <deny users="?"/>

</authorization>

<membership defaultProvider="p1">

   <providers>

      <add name="p1"

           connectionStringName="connstr"

           type="System.Web.Security.SqlMembershipProvider"

           requiresQuestionAndAnswer="false"/>

   </providers>

</membership>

<profile defaultProvider="p2">

   <providers>

      <add name="p2"

           connectionStringName="connstr"

           type="System.Web.Profile.SqlProfileProvider"/>

   </providers>

   <properties>

      <add name="FullName"/>

      <add name="DOB" type="System.DateTime"/>

      <group name="Address">

      <add name="Street"/>

      <add name="Country"/>

      <add name="PostalCode"/>

      </group>

   </properties>

</profile>

Review the above markup carefully, and you'll notice the following:

• The authentication section sets the authentication mode to Forms. The forms tag sets the URL of the login page by using the loginUrl attribute.
  
• The authorization section disables anonymous users by setting the users attribute of the deny tag to "?".
  
• The membership section configures a membership provider named p1. (You can change this any name you choose.)
  
• The connectionStringName attribute specifies the database that will be used for storing membership information.
  
• The type attribute indicates the class that will act as the membership provider. You use the built-in SQL Membership provider called SqlMembershipProvider.
  
• The requiresQuestionAndAnswer attribute indicates that you do not intend to accept a secret question and answer from the end user at the time of registration.
  
• The profile section configures a profile provider named p2 and various profile properties. The significance of the connectionStringname and type attributes is same as for the membership section. Note, however, that this time the type is a SqlProfileProvider class. The properties section defines profile properties and groups.
  
• You defined two simple properties called FullName and DOB and a property group called Address. The Address group further contains three properties: street, country, and postalcode. The DOB property is of type DateTime; therefore, its type attribute is set to System.DateTime.

Now that you have configured your web site for using forms authentication and membership services, it's time to expose Membership and Profile services to the client-side AJAX code. The web.config file will have a pre-defined section called webServices. By default, all its content is commented. You need to un-comment and modify it so that it looks as shown below:

<webServices>

   <authenticationService enabled="true"

   requireSSL="false"/>

   <profileService enabled="true"

   readAccessProperties="FullName,DOB,Address.Street,Address.Country,

                         Address.PostalCode"

   writeAccessProperties="FullName,DOB,Address.Street,Address.Country,

                          Address.PostalCode"/>

</webServices>

The authenticationService tag is used to expose forms authentication and membership services to AJAX code. The enabled attribute governs whether AJAX code can avail membership services. The requireSSL attribute indicates whether the authentication is happening over SSL. Similarly, the Profile service is exposed to AJAX code by using the profileService tag. The readAccessProperties and writeAccessProperties attributes of the profileService tag specify the profile properties that are readable and writable, respectively. Notice how the grouped properties are specified using the dot (.) notion. If you do not include a specific profile property in these attributes, it will not be accessible to the client code.

Applying forms authentication ensures that all the forms of the web site except the login page are secured. However, you want your registration page to be unsecured because new users will need to access it. Do this by adding a location section in the web.config file as shown below:

<location path="register.aspx">

   <system.web>

      <authorization>

         <allow users="*"/>

      </authorization>

   </system.web>

</location>

The path attribute of the location tag specifies a virtual path of a file or folder that is to be configured. It then allows access to all the users using the authorization section and allow tag.

This completes the web site configuration. Now, you will move on to develop the required web forms.

User Registration

First of all, you will create the user registration page. Add a new web form named Registration.aspx. Drag and drop a ScriptManager control from the toolbox (see Figure 2).

Figure 2. Drag and Drop a ScriptManager Control

Also, drag and drop an UpdatePanel and UpdateProgress control on the web form. The UpdatePanel control represents a part of the total web form that can be refreshed without causing a post back of the entire form. The UpdateProgress control is used to display a progress message while the UpdatePanel is being refreshed.

Drag and drop a Label control inside the UpdateProgress control and set its Text property to "Please wait...". Also, set its AssociatedUpdatePanelID property to the ID of the UpdatePanel control. The AssociatedUpdatePanelID property links the UpdateProgress with an UpdatePanel.

Add a table into the UpdatePanel and design it as shown in Figure 3.

Figure 3. Design for Table in the UpdatePanel

The first column of the table contains Label controls that act as prompts for the textboxes. The second column of the table contains TextBox controls. Each TextBox control is validated by using a RequiredFieldValidator control. The TextMode property of the password and confirm password textboxes is set to Password. Similarly, the TextMode property of the street address textbox is set to MultiLine.

There is a Button called "Check Availability" that the end user can use to check the availability of a user ID. The "Check Availability" button will make an AJAX call to the web form to decide whether the specified user ID is available for registration. Set the OnClientClick property of the "Check Availability" button to "return CheckAvailability();" (CheckAvailability() is a client-side JavaScript function that you will write later). This function will call a web method to decide whether the user ID is available for registration. Finally, the Register button will create the user in the system with the help of the Membership features. The Label at the bottom is used for displaying success or error messages.

Now, go in the code behind of the Register.aspx and add a static web method called CheckAvailability. The following is the complete code of the method:

[WebMethod]

public static bool CheckAvailability(string uid)

{

   MembershipUser user = Membership.GetUser(uid);

   if (user == null)

   {

      return true;

   }

   else

   {

      return false;

   }

}

You might be wondering why you added a web method inside a web form. Remember that you have a "Check Availability" button that is supposed to check whether the specified user ID is available for registration. You will be making an AJAX call to do that. ASP.NET AJAX allows you to call web methods defined in web forms via an object called PageMethods. Therefore, you marked the CheckAvailability() method with a [WebMethod] attribute. Note that you must refer to the System.Web.dll and import the System.Web.Services namespace to use the [WebMethod] attribute.

The CheckAvailability() method accepts a user ID and returns true if that ID is available for registration. Inside, it calls the GetUser() method of the Membership object. The GetUser() method returns an instance of the MembershipUser class that represents the specified user. If it returns null, it indicates that the specified user doesn't exist and accordingly true or false is returned to the caller.

When the user clicks the Register button, you need to add user details in the membership and profile tables. Use the Membership and Profile objects to do this BECAUSE ASP.NET AJAX doesn't allow you to create users from client-side code. The following code shows the Click event handler of the Register button:

protected void Button1_Click(object sender, EventArgs e)

{

   try

   {

      MembershipUser user   = Membership.CreateUser

      (TextBox2.Text, TextBox3.Text, TextBox5.Text);

      ProfileCommon pc      = Profile.GetProfile(user.UserName);

      pc.FullName           = TextBox1.Text;

      pc.DOB                = DateTime.Parse(TextBox6.Text);

      pc.Address.Street     = TextBox7.Text;

      pc.Address.Country    = TextBox8.Text;

      pc.Address.PostalCode = TextBox9.Text;

      pc.Save();

      lblMsg.Text           = "User created successfully!";

   }

   catch (Exception ex)

   {

      lblMsg.Text = ex.Message;

   }

}

You call the CreateUser() method of the Membership object to create the user and pass user ID, password, and email. The CreateUser() method returns an instance of MembershipUser representing the newly created user. At this point, the user is not authenticated, so you cannot set the user's profile directly via the Profile object. Instead, you call the GetProfile() method of the Profile object. The GetProfile() method returns an instance of the ProfileCommon class. Through this instance, you set various profile properties. Once all the profile properties are saved, the Save() method of the ProfileCommon class is called to save profile information to the underlying database. A success message is then displayed in a Label control. Any exceptions during the registration process are captured BY using try-catch blocks and an error message is displayed in a Label control.

Now, code the client-side CheckAvailability() function. Switch to the HTML source view of the Register.aspx and add a script block in the HEAD section of the page. Then, add the following functions in the script block:

function CheckAvailability()

{

   var uid=document.getElementById('TextBox2').value;

   if(uid=="")

   {

      alert('Please enter user ID!');

      return false;

   }

   PageMethods.CheckAvailability(uid,OnComplete);

   return false;

}

function OnComplete(result)

{

   var lblMsg=document.getElementById('lblMsg');

   if(result)

   {

      lblMsg.innerText="The ID is available!";

   }

   else

   {

      lblMsg.innerText="The ID is unavailable!";

   }

}

The CheckAvailability() function retrieves the user ID textbox using the getElementById() method of the HTML DOM, which accepts the ID of an element and returns a reference to it. The code checks whether the user ID is empty and, if so, displays an error message. It then calls the CheckAvailability() web method via the PageMethods object and passes the specified user ID to it. The PageMethods object is a built-in object provided by ASP.NET AJAX that allows you to call web methods defined in web forms. The second parameter of the CheckAvailability() call is nothing but the name of another JavaScript function (OnComplete in this example) that gets called after the web method call completes. You may find this mechanism a bit odd, but remember that ASP.NET AJAX communication is always asynchronous. The OnComplete() function receives the return value of the web method as a result parameter. It then simply displays a success or error message in a Label control. Note that the CheckAvailability() JavaScript function returns false so that there won't be any post back.

This completes your registration page. To test it, run the Register.aspx in the browser and try creating new users. Also, check how the "Check Availability" button works. Figure 4 shows a sample run of the web form.

(Full Size Image)

Figure 4. Sample Run of the Web Form

Developing a Login Page

Now that users can register themselves with the web site, you need to provide a facility that enables them to log in and access various pages. To do so, add a new web form called Login.aspx to the web site. Remember that you have set the loginUrl attribute of the forms tag to Login.aspx. Drag and drop a ScriptManager control on it and design the login page as shown in Figure 5 by assembling various controls.

Figure 5. The Login Page Design

As you can see, the login page consists of textboxes for entering a user ID and password. The "Remember Me" checkbox allows you to preserve your logged-in status even after closing the browser window. The TextMode property of the password textbox is set to Password. Further, the OnClientClick property of the Login button is set to "return BeginAuthenticateUser();". BeginAuthenticateUser() is a JavaScript function that uses the ASP.NET AJAX authentication service to authenticate the user. The following is the BeginAuthenticateUser() function:

function BeginAuthenticateUser()

{

   var uid;

   var pwd;

   var isPersistent;

   uid=document.getElementById('TextBox1').value;

   pwd=document.getElementById('TextBox2').value;

   isPersistent=document.getElementById('CheckBox1').checked;

   Sys.Services.AuthenticationService.login

   (uid,pwd,isPersistent,null,null,

   EndAuthenticateUser,OnError,uid);

   return false;

}

The BeginAuthenticateUser() JavaScript function retrieves the user IDs and passwords entered in their respective textboxes. It also retrieves the status of the "Remember Me" checkbox. ASP.NET AJAX provides a built-n class called AuthenticationService that resides in the Sys.Services namespace. Remember that the Sys.Services namespace is defined by the client-side framework of ASP.NET AJAX. The AuthenticationService class offers two methods: login() and logout(). The code above used the login() method, which takes in all eight parameters. Their significance is listed below:

Parameter Significance

1. A user ID


2. A password


3. A boolean value indicating whether an authentication cookie will be persistent


4. The web page where the user should be redirect after a successful login


5. Reserved for future use


6. A callback function that will be called after a successful login (EndAuthenticateUser in this example)


7. A callback function that will be called in case a login attempt fails (OnError in this example)


8. A custom value that is passed to the callback functions

If the user is successfully authenticated, the EndAuthenticateUser function will be called. The following is the EndAuthenticateUser function:

function EndAuthenticateUser(result,userContext,methodName)

{

   if(result)

   {

      window.location='default.aspx';

   }

   else

   {

      alert("Unable to login! Please check user id and password!!");

   }

}

The EndAuthenticateUser() function takes three parameters: the result of the login operation, the user context that you passed earlier in the eighth parameter of the login() method, and the method name. Inside, it checks whether the result is true (in other words, the user is successfully authenticated) and, if so, it sets the location property of the windows object to default.aspx. This way, the user is redirected to the default page after a successful login attempt. If there is any error, an error message is displayed using the alert() function.

The OnError() function is called whenever an error occurs when calling the authentication service. This function is shown below:

function OnError(result,userContext,methodName)
{
   alert(result.get_message());
}

The function simply displays an error message to the user. The result parameter received is actually an object and has a method called get_message() that returns a descriptive error message.

This completes the login page.

Implementing Logout Functionality

Add another web form called Default.aspx. This web form will allow users to logout and manage their profiles. Firstly, you will implement logout functionality. Drag and drop a ScriptManager control on the Default.aspx and design the web form as shown in Figure 6.

Figure 6. The Web Form Design

The web form consists of a couple of Label controls to display a welcome message to the user. The Logout button allows the user to delete the authentication cookie, thus logging him out. The OnClientClick property of the Login button is set to "return BeginLogOut();" (BeginLogout() is a JavaScript function that you will write later). The "Show My Profile" button toggles the profile panel. The OnClientClick property of the "Show My Profile" button is set to "return BeginProfileLoad();" (you will create the BeginProfileLoad() function later). The profile panel consists of a Panel control containing textboxes to display and show profile property values. It also contains the "Save Profile" button for saving changes made to the profile values. The OnClientClick property of the "Save Profile" button is set to "return BeginSaveProfile();" (the BeginSaveProfile() function will be coded later).

In the Page_Load event of the web form, you set the welcome label to the ID of the user. The following code shows how:

protected void Page_Load(object sender, EventArgs e)
{
   Label4.Text = Membership.GetUser().UserName;
}

The code simply retrieves the user name of the current user and assigns it to the label. Note that the GetUser() method of the Membership object returns an object of type MembershipUser. The UserName property of the MembershipUser class is then called. You need to display the user name from the server-side code because ASP.NET AJAX doesn't provide any way to retrieve it via client-side code.

Now, switch to the HTML source view of Default.aspx and write the BeginLogOut() and EndLogOut() JavaScript functions as shown below:

function BeginLogOut()

{

   Sys.Services.AuthenticationService.logout

   (null,EndLogout,OnError,null);

   return false;

}

function EndLogout(result)

{

   //nothing here

}

The BeginLogOut() function again uses the AuthenticationService class. This time, it calls the logout() method of AuthenticationService. The logout() method takes the following four parameters:

• The first parameter indicates a URL where the user should be taken after successful logout.
  
• The second parameter specifies a callback function to be called when the logout operation is complete.
  
• The third parameter specifies a callback function to be called when the logout operation fails.
  
• The fourth parameter indicates a custom context information.

As before, the BeginLogOut() function returns false so that there is no post back. The EndLogOut() function doesn't perform any action in this example.

Reading Profile Properties

Initially, the profile panel should be hidden from the end user. This is done in the pageLoad() JavaScript function. Note that the pageLoad() function is called by the ASP.NET AJAX framework when the page loads in the browser. You can think of it as a client-side counterpart of server-side Page_Load event. The pageLoad() function is shown below:

function pageLoad()
{
   var panel3=document.getElementById('Panel3');
   panel3.style.visibility="hidden";
}

The pageLoad() function simply sets the visibility property of the style object to hidden, thus hiding the profile panel.

When you click on the "Show My Profile" button, the profile panel needs to be displayed with the profile property values filled in. The BeginProfileLoad() function does this job:

function BeginProfileLoad()

{

   if(event.srcElement.value=="Show my profile")

   {

      var panel3=document.getElementById('Panel3');

      panel3.style.visibility="visible";

      event.srcElement.value="Hide my profile";

      Sys.Services.ProfileService.load

      (null,EndProfileLoad,OnProfileFailed, null);

   }

   else

   {

      var panel3=document.getElementById('Panel3');

      panel3.style.visibility="hidden";

      event.srcElement.value="Show my profile";

   }

   return false;

}

The BeginProfileLoad() function toggles visibility of the profile panel. If the profile panel is to be displayed, then you must populate various textboxes with profile values. The ASP.NET AJAX framework provides a class called ProfileService that allows you to work with profile properties. The load() method of the ProfileService class loads profile property values. The load() method takes four parameters, which do the following:

Parameter
Significance

1. An array of property names that are to be loaded. If you have too many profile properties, then it makes sense to load the ones that you really want to use. This will improve the performance of your page.


2. A callback function that will be called when the load operation is completed


3. A callback function that will be called if the load operation fails


4. Custom context information, if any

Once the profile is loaded the EndProfileLoad() function is called. This is the EndProfileLoad():

function EndProfileLoad(numProperties, userContext, methodName)

{

   document.getElementById('TextBox3').value =

      Sys.Services.ProfileService.properties.FullName;

   document.getElementById('TextBox4').value =

      Sys.Services.ProfileService.properties.DOB;

   document.getElementById('TextBox5').value =

      Sys.Services.ProfileService.properties.Address.Street;

   document.getElementById('TextBox6').value =

      Sys.Services.ProfileService.properties.Address.Country;

   document.getElementById('TextBox7').value =

      Sys.Services.ProfileService.properties.Address.PostalCode;

}

The EndProfileLoad() function receives three parameters: number of properties that are loaded, context information that is supplied to the load() function, and method name. It then populates the textboxes with the profile property values. The ProfileService class exposes profile properties via the properties collection. Remember that only the properties specified in the readAccessProperties attribute of the profileService tag of web.config are exposed. The properties and groups are accessed with the familiar dot (.) notion.

Modifying Profile Properties

When profile property values are displayed in various textboxes, the user can change them and click on the "Save Profile" button. Clicking on the "Save Profile" button calls the BeginSaveProfile() function, which is shown here:

function BeginSaveProfile()

{

   Sys.Services.ProfileService.properties.FullName=

      document.getElementById('TextBox3').value;

   Sys.Services.ProfileService.properties.DOB=

      document.getElementById('TextBox4').value;

   Sys.Services.ProfileService.properties.Address.Street=

      document.getElementById('TextBox5').value;

   Sys.Services.ProfileService.properties.Address.Country=

      document.getElementById('TextBox6').value;

   Sys.Services.ProfileService.properties.Address.PostalCode=

      document.getElementById('TextBox7').value;

   Sys.Services.ProfileService.save

   (null,EndSaveProfile,OnProfileFailed,null);

   return false;

}

The code again uses the ProfileService class and its properties collection to assign new values. Once all the profile properties are set, it calls the save() method of the ProfileService class. The save() method takes the same four parameters as the load() method (in other words, the array of properties to write, the callback function to be called after successful saving, the callback function to be called after unsuccessful save, and custom context information). The EndSaveProfile() function simply displays a message box to the user:

function EndSaveProfile(numProperties, userContext, methodName)
{
   alert('Your profile is saved successfully!');
}

That's it! You just completed your AJAX-driven membership and profile pages. You now can log in to the web site and test the profile features. Figure 7 shows a sample run of the default.aspx.

Figure 7. A Sample Run of the Default.aspx

Consuming Membership and Profile Features from the Client Side

ASP.NET AJAX provides a handy way to consume membership and profile features. To consume these features, you need to enable them by using the authenticationService and profileService tags of web.config. Once enabled, you can use the AuthenticationService and ProfileService classes to consume them.

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