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ptg 222 Chapter 9 Security Model def user = request.subject.remoteUser[] def groups = []+request.subject.groups[] %> <h1>Hello ${user}</h1> <h2>Your group(s):</h2> <ul> <% groups.each { g -> %> <li>${g}</li> <% } %> </ul> <h2><a href="<%= getRelativeUri('/logout.gt')%>">Logout<a></h2> </body> </html> The final page we need to add is a logout page. It is always a good practice to provide a means to enable your users to log out of an application. Listing 9.9 creates a logout page. You often should do some housekeeping on the “user” Global Context and remove any session-like variables that you do not want to persist into the user’s next access to the site. This could include sensitive data that should not be persisted or just as a means of good housekeeping. Listing 9.9 Logout Page (/public/logout.gt) <html> <head> <title>Logout</title> </head> <body> <% zero.core.security.LoginService.logout(); %> <h1>You have been logged out</h1> <h2>Return to <a href="<%= getRelativeUri(‘/index.gt’) %>">Home page</a>. </h2> </body> </html> Download from www.wowebook.com ptg Tes ting th e Sec ure A ppl icat ion 223 Figure 9.10 Login page Figure 9.11 Login page after failed login Testing the S e c u re Application At this point, we have all the pieces required to test our secure application. Start the application, and open your browser to the secure https port defined in the configuration file. In the preceding example, we had chosen port number 9443, so your URL is https://localhost:9443/. You should be presented with our insecure main landing page without being prompted for a login, as shown in back in Figure 9.4. Click the link to go to the secure page. If everything is configured properly, you will be redirected to the login page (see Figure 9.10) for user authentication. On subsequent attempts to access the secure page after logging in, you will have a valid browser token and will not need to log in again. To test out our failed login logic, enter either a bad username or wrong password, and click Submit. You will be returned to the login page and an appropriate error message will be displayed, as seen in Figure 9.11. At this point, log in using your correct username and password and verify that you are able to log in. We now look at our secured page with information about your user, as shown in Figure 9.12. To close out our test, click the logout link, which will put you on the logout page shown in Figure 9.13. To verify that you are actually logged out, manually enter the secured landing page URL: https://localhost:9443/my/index.gt. You should be redi- rected to the login page once again. You’ve done it! A nice, clean user-secured application. Download from www.wowebook.com ptg 224 Chapter 9 Security Model Figure 9.13 Logout page Directory Server Configuration Directory servers, which implement the Lightweight Directory Access Protocol (LDAP), are probably the most common user repository in most enterprises. A directory server consists of a hierarchical database that stores user information or users’ profile information by a unique distin- guished name (DN), which is equal to a path and through which an application is able to search and retrieve information. Based on this information, a directory server is an ideal ID source for this application functionality. Other than the WebSphere sMash configuration settings, you’ll see that this is very similar to the solution we just built. Although there are some syntax contortions that are necessary to deal with LDAP, it is very effective in what it does. Namely, directory servers store user information with quick and secure identification access. Because many LDAP installations are unique in how they store and define the data struc- ture, we can’t cover all situations. Consult your directory server’s documentation and site admin- istrator for more details about the required search and filtering constraints. We show a generic configuration and leave it as an exercise for you and your LDAP admin- istrator to determine the proper arguments to access your site’s LDAP particulars. The first thing we need to do is enable the application for LDAP authentication. After a user is logged in, the only attributes we have by default are the unique user ID, which (depending on the LDAP configuration) may be different than the user ID used to log in and the group memberships, Figure 9.12 Secured landing page Download from www.wowebook.com ptg Directory Server Configuration 225 Table 9.2 User Authentication Variables LDAP Attribute Global Context Entry Unique user ID request.subject.remoteUser[] Group membership request.subject.groups[] as shown in Table 9.2. In almost any situation, you’ll want more information than what is provided here, so we’ll also look to see how to obtain extended LDAP attributes for a given user. Let’s define the configuration settings to authenticate with the LDAP server. Edit your application’s zero.config file and add the information, as shown in Listing 9.10. You need to get the actual LDAP values from your friendly system administrator. Listing 9.10 LDAP-Specific Configuration Settings # # LDAP Settings # /config/security/userservice/registryType="ldap" # General LDAP Auth /config/security/userservice/ldap += { "jndiProviderUrl" : "ldap://ldap.acme.com:389/", "ldapUserIdSearchFilterPattern" : "(&(mail={0})(objectclass=inetOrgPerson))", "ldapGroupSearchFilterPattern" : "(&(member={0}) (objectclass=groupOfNames))", "ldapUserIdBaseDn" : "ou=people,o=acme.com", "ldapGroupBaseDn" : "ou=memberlist,ou=groups,o=acme.com" } # Token Support - Pick Simple or LTPA2. # SimpleToken support /config/security/token/simple += { "tokenExpiration": 120, "ssoDomains" : ["acme.com"] } Download from www.wowebook.com ptg 226 Chapter 9 Security Model # LTPAToken2 support # Referenced key is relative to /config dir. #@include "security/token/ltpa2.config"{ # "keyImportFile": "myLTPA.key", # "keyPassword" : "myPassword", # "ssoDomains" : ["acme.com"] #} These are the only configuration items we need to add to the existing values in the security sample application. Everything else remains as it is. Let’s take a quick walk-through of these set- tings. First, we need to set the security registry type to LDAP. The second stanza defines the LDAP server host, its port, and its query settings. Again, the actual values here are dependent on the server installation you want to use. Directory Server User Details Next, we need to create a method to assist us in obtaining more details about the authenticated user. To do this, we’ll need to obtain the Groovy-Ldap package from the Apache project. 3 To use Groovy-Ldap, download and extract the package to a temporary directory. Copy the included JAR file to your project’s /lib directory. Next, create a new groovy file in your application named /app/scripts/helpers/ldap.groovy, and populate it with the code shown in Listing 9.11. You will need to alter the LDAP-specific variables to match your environment. A second and even bet- ter approach would be to put these values into the application’s zero.config file and reference the settings appropriately. In this LDAP helper method, we establish a connection to the LDAP server, set up a search query, and cache the results into the user context object for future use. Be watchful of the objects that are returned from these LDAP calls, as the query might return an array of objects, and the values for the entries will be either a string or an array of strings. It’s best to first test the type of the values before using them. For details on how to use Groovy-Ldap, and to see how you can perform advanced searches, add, updates, and deletes, refer to the documenta- tion on the Apache.org website. Listing 9.11 LDAP User Details Function package helpers def getUser() { if ( ! user.me[] ) { 3 GroovyLdap: http://cwiki.apache.org/DIRxSBOX/groovy-ldap.html Download from www.wowebook.com ptg Directory Server User Details 227 // Replace these with your site specific values def ldapServer = ‘ldap://acme.com:389/ou=people,o=acme.com’ def ldapSearchFilter = ‘(&(objectClass=person)(uid={0}))’ def uid = request.subject.remoteUser[] def ldap = org.apache.directory.groovyldap.LDAP.newInstance( ldapServer ) def search = new org.apache.directory.groovyldap.Search() search.filter = ldapSearchFilter search.filterArgs = [ uid.toLowerCase() ] def results = ldap.search(search) if ( results != null && results.size() > 0 ) { user.me = results[0] logger.INFO{ "Me: ${user.me[]}" } } } return user.me[] } Now we have everything we need to deal with our user, and all his personal attributes. Because we protected the /my URL in the initial configuration, let’s create an index.gt file there and see what our LDAP server can tell us about our user. Place the code shown in Listing 9.12 into /public/my/index.gt. Listing 9.12 Enhanced User and Group Details Page <% def uid = request.subject.remoteUser[] def groups = ( []+request.subject.groups[] ).sort() def user = invokeMethod(‘helpers/ldap.groovy’,’getUser’, null) %> <table border='1' width="100%" cellspacing='0px' cellpadding='0px'> <tr> <th colspan='2'><h2>Hello ${uid}</h2></th> </tr> <tr> <th><h2>Your LDAP details</h2></th> <th><h2>Your Groups</h2></th> </tr> <tr> <td> Download from www.wowebook.com ptg 228 Chapter 9 Security Model <table border='1' width='100%'> <% user.keySet().sort().each { key -> %> <tr><td>${key}</td><td>${user[key]}</td></tr> <% } %> </table> </td> <td> <ul> <% groups.each { g -> %> <li>${g}</li> <% } %> </ul> </td> </tr> </table> The code should be self-explanatory, but we simply pull out our user’s unique ID, his groups, and the user object from our helper method. Then we sort the keys of the user object to improve readability and dump its contents. Finally, we dump the groups as well. The results are rather voluminous and potentially confidential in nature, depending on your LDAP’s configura- tion. You have to try this yourself to see the results—when I ran this on myself at my company, there was little that I’d be comfortable showing the world. Run this sample application using your own companies’ LDAP server, and examine the details maintained about you as an employee. OpenID Configuration One of the newer and more exciting authentication concepts is called OpenID. It is a decentral- ized process, where essentially any service provider can act as an trustee for user authentication. Although the concept is that you would have a single login identity that would work across the Internet, its common to have several different identities spread across different service providers. You actually might already have an OpenID—many social sites such as Facebook, Google, and Yahoo!, to name a few, also act as OpenID providers. To find out if you have an ID, or want to create one, point your browser to www.openid.net. Here, you can see which sites support OpenID, as well as create your own personal OpenID. You then can build an OpenID-based WebSphere sMash application and impress all your friends. As with other authentication schemes, we have a little configuration setup that we need to make, and then it is simply a matter of creating a custom Login form. First, we need to add a dependency to the zero.security.openid module into the project. To do this in AppBuilder, select Download from www.wowebook.com ptg OpenID Configuration 229 the Dependencies tab, click the Add button, search for “opened,” and click Add. In Eclipse, open the project’s /config/ivy.xml file, click Add, search on zero:zero.security.openid, and click OK. Additionally, we need to enable security to our zero.config and define a few OpenID-specific settings, as shown in Listing 9.13. This is a fairly generic setup, and specific details can be found in the Project Zero documentation under the security section of the developer guide. Listing 9.13 OpenID Security Configuration # # OpenID Settings # /config/security/userservice/registryType="openid" # specify the OpenID loginPage and associated login related # configuration @include "security/openidLoginURL.config" { "openidLoginPage": "/openidlogin.gt", # [optional] require these openid profile entries "sregRequired": ["email","nickname","gender"], # optionally send date of birth, full name, country, # timezone and language if available "sregOptional": ["dob","fullname","country","timezone","language"], # URL describing how application will leverage simple registration # required and optional attributes "sregPolicyURL" : "http://www.projectzero.org", "allowedOpenidDomains" : ["myopenid.com"] } #specify the security constraints @include "security/openidAuthentication.config"{ "conditions": "/request/path =~/my(/.*)?" } OpenID also supports standard profile information that may be optionally requested by consuming applications. This is meant to provide a better web experience and not to expose any confidential user information. Most OpenID providers allow the entry of one or more profile sets Download from www.wowebook.com ptg 230 Chapter 9 Security Model Table 9.3 OpenID Profile Fields OpenID Profile Fields Description nickname User’s preferred nickname. email User’s email address. fullname User’s full name. dob User’s data of birth (YYYY-MM-DD). Zeros may be used for non- revealed values, such as birth year, which might result in something similar to: 0000-07-04. gender User gender: either “M” for male, or “F” for female. postcode UTF-8 string-free text that should conform to the end user’s. country The end user’s country of residence in standard two-digit country code format. language End user’s preferred language timezone ASCII string from TimeZone database. For example: “Europe/Paris” or “America/Los_Angeles.” Securing Outbound Connections Up until this point, we have been discussing how to secure connection requests from external browsers or applications coming into your applications services. Let’s shift gears a bit and deal with securing outbound connections to other services. Typi- cally, you will be using the Connection class to make outgoing connections. These can be normal, insecure HTTP-based calls, and authenticated requests to secured HTTPS-based services. The solution here is to pre-define the secure connections in the zero.config file, including the required username and password; then we can make the calls as needed from our application code. Start by defining your secure outbound connection(s) in the zero.config file, as shown in Listing 9.14. Here, we define a connection URL pattern, and the user and password values. You can enter the password in clear text, but it’s better to obfuscate it using XOR encoding. Even with encoding, storing passwords in a configuration is a concern, and you should make an effort to 4 OpenID Simple Registration Extension: http://openid.net/specs/openid-simple-registration-extension-1_0.html that you can specify to be used by consuming websites. The currently defined profile fields are listed in Table 9.3. More information can be found at the OpenID Simple Registration Extension. 4 Download from www.wowebook.com ptg OpenID Configuration 231 Figure 9.14 Password encoding using AppBuilder console ensure that this file is protected from unauthorized viewing. To encode the password, just run the zero encode {password} command from either the command line or from the console tab in AppBuilder, as shown in Figure 9.14. Listing 9.14 Defining Outbound Connections in Configuration File /config/connection/destinations += { "https://crownjewels.acme.com/*" : { "connection" : { "protocol" : "https", "config" : { "userid": "wecoyote@acme.com", "password":"<xor>Mj44Njwoby07" } } } } After we have our outbound connection pattern defined, all we have to do is to set up a new connection call to our desired service. WebSphere sMash compares the outbound connection URL with the pre-defined destination patterns, and if a match is made, will automatically apply the appropriate user and password creden- tials to the connection. This keeps our credentials external to our application logic, which is always a good thing. Listing 9.15 shows a code fragment that makes a connection to the remote server. Download from www.wowebook.com . "ldapGroupBaseDn" : "ou=memberlist,ou=groups,o=acme.com" } # Token Support - Pick Simple or LTPA2. # SimpleToken support /config/security/token/simple += { "tokenExpiration":. invokeMethod(‘helpers/ldap.groovy’,’getUser’, null) %> <table border='1' width="100%" cellspacing='0px' cellpadding='0px'> <tr> <th colspan='2'><h2>Hello. one, point your browser to www.openid.net. Here, you can see which sites support OpenID, as well as create your own personal OpenID. You then can build an OpenID-based WebSphere sMash application
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