HowdoIperformAuthorizationusingadvancedpolicyexpressionsinNetScaler?

BackgroundAdvancedpolicyexpressionsprovidearichsetofexpressionslikebodybased,DNSbasedexpressionstoadministratorscomparedtoolderclassicones.AdvancedwillbethedefaultexpressioneditorforSession,TrafficandAuthorizationpolicyeditors.Optiontoswitchtoclassicbyclickingon“SwitchtoClassicSyntax”

• Onlyonepolicytype(eitheradvancedorclassic)isallowedtobeboundforatypeofpolicyo E.g.:Allauthorizationpoliciesboundatanylevelmustbeeitheradvancedorclassico AuthorizationpoliciesofAdvanced-typeandTrafficpoliciesofClassictypeareallowed

UsecaseTheadminwantstoblockasetofuserstonotallowthemtoaccessthedownloadpageofcitrix.com.Forthistheadminhascreatedausergroupcalled‘BlacklistUserGroup’,anyuserthatisapartofthisgroupshouldnotbeallowedtoaccessthedownloadpage.StepstoachievethisWithadvancedpolicyexpressions,theadministratorcancreateanauthorizationpolicyonhttprequestandlinkittotheBlackListUserGroup.PleaseseebelowthestepsfromtheNetScalerGUI:

1. LogintotheGUI,navigatetothispath:Configuration->NetScalerGateway->Policies->Authorization

2. Clickontheaddbutton

3. Createanauthorizationpolicy.Inourcase,wehavecreatedthefollowing-

4. Clickonexpressioneditorandusesimpleandintuitivedropdownstocreateapolicyexpression.Forustheexpressionis-http.req.hostname.contains("citrix.com")&&http.req.url.contains("downloads")

Usingtheoperator‘&&’andthencreatinganotherexpressionasbelow:

Finally,thisiswhattheexpressionlookslike:

5. BindthisauthorizationpolicytotheAAA-Usergroup.Navigateto:Configuration->NetScaler

Gateway->UserAdministration->AAAGroups.Inthiscase,weselectBlackListUserGroupandBindthispolicytoit.

LetustakealookattheAuthorizationPolicywhichisboundtothisgroup:

Now,letustestthisout:

1. Wehaveauser–BlacklistuserwhichisapartoftheBlackListUserGroup.Thisusershouldnotbeallowedtoaccessthedownloadspageofcitrix.com

2. LaunchesCitrix.comfromthebookmarkssetasbelow:

Thewebsitelaunchesasshownbelow.

3. Theuserclicksonthedownloadstabonthewebsiteandisdeniedaccesswiththebelowmessage.

Therefore,wehavethetestedourconfigurationoftheauthorizationpolicytodenyaccesstoblacklisteduserstothedownloadpageofcitrix.com