Using AD for your authentication is a great idea, since you still need to add everyone, and there is no need for additional login for intranet users.
You are correct that ASP.NET allows you to use a provider that will allow you to authenticate against AD, although nothing is included to give you support for group membership (although this is pretty trivial to implement, if you want, I can provide a sample).
The real problem is whether you want to use AD groups to determine permissions in each application, yes?
If so, you have the opportunity to create your own RoleProvider for ASP.NET, which can also be used by WinForms and WPF applications through ApplicationServices. This RoleProvider could associate the user ID in AD with groups / roles for the application, which you can save in your own database, which also allows each application to allow the administration of these roles without requiring additional privileges in AD for these admins.
If you want, you can also redefine and merge application roles with AD groups, so if they are in some global Admin group in AD, they get full permission in the application regardless of membership in the application role. Conversely, if they have a group or property in AD to say that they were fired, you can ignore all membership in App roles and restrict all access (since HR probably won’t remove them from each application, assuming that they even know everything about them!).
Sample code added as requested:
NOTE: based on this original work http://www.codeproject.com/Articles/28546/Active-Directory-Roles-Provider
For your ActiveDirectoryMembershipProvider you only need to implement the ValidateUser method, although you can implement more if you want, the new AccountManagement namespace makes this trivial:
// assumes: using System.DirectoryServices.AccountManagement; public override bool ValidateUser( string username, string password ) { bool result = false; try { using( var context = new PrincipalContext( ContextType.Domain, "yourDomainName" ) ) { result = context.ValidateCredentials( username, password ); } } catch( Exception ex ) { // TODO: log exception } return result; }
For your video provider, this works a little more, there are some key issues that we discovered during google searches, such as the groups you want to exclude, the users you want to exclude, etc.
It’s probably worth a full blog post, but this should help you get started, caching your search for session variables, as an example of how you could improve performance (since the full cache sample is too long).
using System; using System.Collections.Generic; using System.Collections.Specialized; using System.Configuration.Provider; using System.Diagnostics; using System.DirectoryServices; using System.DirectoryServices.AccountManagement; using System.Linq; using System.Web; using System.Web.Hosting; using System.Web.Security; namespace MyApp.Security { public sealed class ActiveDirectoryRoleProvider : RoleProvider { private const string AD_FILTER = "(&(objectCategory=group)(|(groupType=-2147483646)(groupType=-2147483644)(groupType=-2147483640)))"; private const string AD_FIELD = "samAccountName"; private string _activeDirectoryConnectionString; private string _domain; // Retrieve Group Mode // "Additive" indicates that only the groups specified in groupsToUse will be used // "Subtractive" indicates that all Active Directory groups will be used except those specified in groupsToIgnore // "Additive" is somewhat more secure, but requires more maintenance when groups change private bool _isAdditiveGroupMode; private List<string> _groupsToUse; private List<string> _groupsToIgnore; private List<string> _usersToIgnore; #region Ignore Lists // IMPORTANT - DEFAULT LIST OF ACTIVE DIRECTORY USERS TO "IGNORE" // DO NOT REMOVE ANY OF THESE UNLESS YOU FULLY UNDERSTAND THE SECURITY IMPLICATIONS // VERYIFY THAT ALL CRITICAL USERS ARE IGNORED DURING TESTING private String[] _DefaultUsersToIgnore = new String[] { "Administrator", "TsInternetUser", "Guest", "krbtgt", "Replicate", "SERVICE", "SMSService" }; // IMPORTANT - DEFAULT LIST OF ACTIVE DIRECTORY DOMAIN GROUPS TO "IGNORE" // PREVENTS ENUMERATION OF CRITICAL DOMAIN GROUP MEMBERSHIP // DO NOT REMOVE ANY OF THESE UNLESS YOU FULLY UNDERSTAND THE SECURITY IMPLICATIONS // VERIFY THAT ALL CRITICAL GROUPS ARE IGNORED DURING TESTING BY CALLING GetAllRoles MANUALLY private String[] _defaultGroupsToIgnore = new String[] { "Domain Guests", "Domain Computers", "Group Policy Creator Owners", "Guests", "Users", "Domain Users", "Pre-Windows 2000 Compatible Access", "Exchange Domain Servers", "Schema Admins", "Enterprise Admins", "Domain Admins", "Cert Publishers", "Backup Operators", "Account Operators", "Server Operators", "Print Operators", "Replicator", "Domain Controllers", "WINS Users", "DnsAdmins", "DnsUpdateProxy", "DHCP Users", "DHCP Administrators", "Exchange Services", "Exchange Enterprise Servers", "Remote Desktop Users", "Network Configuration Operators", "Incoming Forest Trust Builders", "Performance Monitor Users", "Performance Log Users", "Windows Authorization Access Group", "Terminal Server License Servers", "Distributed COM Users", "Administrators", "Everybody", "RAS and IAS Servers", "MTS Trusted Impersonators", "MTS Impersonators", "Everyone", "LOCAL", "Authenticated Users" }; #endregion /// <summary> /// Initializes a new instance of the ADRoleProvider class. /// </summary> public ActiveDirectoryRoleProvider() { _groupsToUse = new List<string>(); _groupsToIgnore = new List<string>(); _usersToIgnore = new List<string>(); } public override String ApplicationName { get; set; } /// <summary> /// Initialize ADRoleProvider with config values /// </summary> /// <param name="name"></param> /// <param name="config"></param> public override void Initialize( String name, NameValueCollection config ) { if ( config == null ) throw new ArgumentNullException( "config" ); if ( String.IsNullOrEmpty( name ) ) name = "ADRoleProvider"; if ( String.IsNullOrEmpty( config[ "description" ] ) ) { config.Remove( "description" ); config.Add( "description", "Active Directory Role Provider" ); } // Initialize the abstract base class. base.Initialize( name, config ); _domain = ReadConfig( config, "domain" ); _isAdditiveGroupMode = ( ReadConfig( config, "groupMode" ) == "Additive" ); _activeDirectoryConnectionString = ReadConfig( config, "connectionString" ); DetermineApplicationName( config ); PopulateLists( config ); } private string ReadConfig( NameValueCollection config, string key ) { if ( config.AllKeys.Any( k => k == key ) ) return config[ key ]; throw new ProviderException( "Configuration value required for key: " + key ); } private void DetermineApplicationName( NameValueCollection config ) { // Retrieve Application Name ApplicationName = config[ "applicationName" ]; if ( String.IsNullOrEmpty( ApplicationName ) ) { try { string app = HostingEnvironment.ApplicationVirtualPath ?? Process.GetCurrentProcess().MainModule.ModuleName.Split( '.' ).FirstOrDefault(); ApplicationName = app != "" ? app : "/"; } catch { ApplicationName = "/"; } } if ( ApplicationName.Length > 256 ) throw new ProviderException( "The application name is too long." ); } private void PopulateLists( NameValueCollection config ) { // If Additive group mode, populate GroupsToUse with specified AD groups if ( _isAdditiveGroupMode && !String.IsNullOrEmpty( config[ "groupsToUse" ] ) ) _groupsToUse.AddRange( config[ "groupsToUse" ].Split( ',' ).Select( group => group.Trim() ) ); // Populate GroupsToIgnore List<string> with AD groups that should be ignored for roles purposes _groupsToIgnore.AddRange( _defaultGroupsToIgnore.Select( group => group.Trim() ) ); _groupsToIgnore.AddRange( ( config[ "groupsToIgnore" ] ?? "" ).Split( ',' ).Select( group => group.Trim() ) ); // Populate UsersToIgnore ArrayList with AD users that should be ignored for roles purposes string usersToIgnore = config[ "usersToIgnore" ] ?? ""; _usersToIgnore.AddRange( _DefaultUsersToIgnore .Select( value => value.Trim() ) .Union( usersToIgnore .Split( new[] { "," }, StringSplitOptions.RemoveEmptyEntries ) .Select( value => value.Trim() ) ) ); } private void RecurseGroup( PrincipalContext context, string group, List<string> groups ) { var principal = GroupPrincipal.FindByIdentity( context, IdentityType.SamAccountName, group ); if ( principal == null ) return; List<string> res = principal .GetGroups() .ToList() .Select( grp => grp.Name ) .ToList(); groups.AddRange( res.Except( groups ) ); foreach ( var item in res ) RecurseGroup( context, item, groups ); } /// <summary> /// Retrieve listing of all roles to which a specified user belongs. /// </summary> /// <param name="username"></param> /// <returns>String array of roles</returns> public override string[] GetRolesForUser( string username ) { string sessionKey = "groupsForUser:" + username; if ( HttpContext.Current != null && HttpContext.Current.Session != null && HttpContext.Current.Session[ sessionKey ] != null ) return ( (List<string>) ( HttpContext.Current.Session[ sessionKey ] ) ).ToArray(); using ( PrincipalContext context = new PrincipalContext( ContextType.Domain, _domain ) ) { try { // add the users groups to the result var groupList = UserPrincipal .FindByIdentity( context, IdentityType.SamAccountName, username ) .GetGroups() .Select( group => group.Name ) .ToList(); // add each groups sub groups into the groupList foreach ( var group in new List<string>( groupList ) ) RecurseGroup( context, group, groupList ); groupList = groupList.Except( _groupsToIgnore ).ToList(); if ( _isAdditiveGroupMode ) groupList = groupList.Join( _groupsToUse, r => r, g => g, ( r, g ) => r ).ToList(); if ( HttpContext.Current != null ) HttpContext.Current.Session[ sessionKey ] = groupList; return groupList.ToArray(); } catch ( Exception ex ) { // TODO: LogError( "Unable to query Active Directory.", ex ); return new[] { "" }; } } } /// <summary> /// Retrieve listing of all users in a specified role. /// </summary> /// <param name="rolename">String array of users</param> /// <returns></returns> public override string[] GetUsersInRole( String rolename ) { if ( !RoleExists( rolename ) ) throw new ProviderException( String.Format( "The role '{0}' was not found.", rolename ) ); using ( PrincipalContext context = new PrincipalContext( ContextType.Domain, _domain ) ) { try { GroupPrincipal p = GroupPrincipal.FindByIdentity( context, IdentityType.SamAccountName, rolename ); return ( from user in p.GetMembers( true ) where !_usersToIgnore.Contains( user.SamAccountName ) select user.SamAccountName ).ToArray(); } catch ( Exception ex ) { // TODO: LogError( "Unable to query Active Directory.", ex ); return new[] { "" }; } } } /// <summary> /// Determine if a specified user is in a specified role. /// </summary> /// <param name="username"></param> /// <param name="rolename"></param> /// <returns>Boolean indicating membership</returns> public override bool IsUserInRole( string username, string rolename ) { return GetUsersInRole( rolename ).Any( user => user == username ); } /// <summary> /// Retrieve listing of all roles. /// </summary> /// <returns>String array of roles</returns> public override string[] GetAllRoles() { string[] roles = ADSearch( _activeDirectoryConnectionString, AD_FILTER, AD_FIELD ); return ( from role in roles.Except( _groupsToIgnore ) where !_isAdditiveGroupMode || _groupsToUse.Contains( role ) select role ).ToArray(); } /// <summary> /// Determine if given role exists /// </summary> /// <param name="rolename">Role to check</param> /// <returns>Boolean indicating existence of role</returns> public override bool RoleExists( string rolename ) { return GetAllRoles().Any( role => role == rolename ); } /// <summary> /// Return sorted list of usernames like usernameToMatch in rolename /// </summary> /// <param name="rolename">Role to check</param> /// <param name="usernameToMatch">Partial username to check</param> /// <returns></returns> public override string[] FindUsersInRole( string rolename, string usernameToMatch ) { if ( !RoleExists( rolename ) ) throw new ProviderException( String.Format( "The role '{0}' was not found.", rolename ) ); return ( from user in GetUsersInRole( rolename ) where user.ToLower().Contains( usernameToMatch.ToLower() ) select user ).ToArray(); } #region Non Supported Base Class Functions /// <summary> /// AddUsersToRoles not supported. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory. /// </summary> public override void AddUsersToRoles( string[] usernames, string[] rolenames ) { throw new NotSupportedException( "Unable to add users to roles. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory." ); } /// <summary> /// CreateRole not supported. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory. /// </summary> public override void CreateRole( string rolename ) { throw new NotSupportedException( "Unable to create new role. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory." ); } /// <summary> /// DeleteRole not supported. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory. /// </summary> public override bool DeleteRole( string rolename, bool throwOnPopulatedRole ) { throw new NotSupportedException( "Unable to delete role. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory." ); } /// <summary> /// RemoveUsersFromRoles not supported. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory. /// </summary> public override void RemoveUsersFromRoles( string[] usernames, string[] rolenames ) { throw new NotSupportedException( "Unable to remove users from roles. For security and management purposes, ADRoleProvider only supports read operations against Active Direcory." ); } #endregion /// <summary> /// Performs an extremely constrained query against Active Directory. Requests only a single value from /// AD based upon the filtering parameter to minimize performance hit from large queries. /// </summary> /// <param name="ConnectionString">Active Directory Connection String</param> /// <param name="filter">LDAP format search filter</param> /// <param name="field">AD field to return</param> /// <returns>String array containing values specified by 'field' parameter</returns> private String[] ADSearch( String ConnectionString, String filter, String field ) { DirectorySearcher searcher = new DirectorySearcher { SearchRoot = new DirectoryEntry( ConnectionString ), Filter = filter, PageSize = 500 }; searcher.PropertiesToLoad.Clear(); searcher.PropertiesToLoad.Add( field ); try { using ( SearchResultCollection results = searcher.FindAll() ) { List<string> r = new List<string>(); foreach ( SearchResult searchResult in results ) { var prop = searchResult.Properties[ field ]; for ( int index = 0; index < prop.Count; index++ ) r.Add( prop[ index ].ToString() ); } return r.Count > 0 ? r.ToArray() : new string[ 0 ]; } } catch ( Exception ex ) { throw new ProviderException( "Unable to query Active Directory.", ex ); } } } }
For example, there will be an example of a substring of a sample configuration:
<roleManager enabled="true" defaultProvider="ActiveDirectory"> <providers> <clear/> <add applicationName="MyApp" name="ActiveDirectory" type="MyApp.Security.ActiveDirectoryRoleProvider" domain="mydomain" groupMode="" connectionString="LDAP://myDirectoryServer.local/dc=mydomain,dc=local" /> </providers> </roleManager>
So much code!
PS: The main parts of the role provider above are based on the work of another person, I do not have a link, but we found it through Google, so a partial loan to this person for the original. We changed it a lot to use LINQ and eliminate the need for a database for caching.