• 1. London, UK
  • 2. New York, NY
  • 3. Sydney, Australia
  • 4. Melbourne, Australia
  • 5. San Francisco, CA
  • 6. Chicago, IL
  • 7. Toronto, Canada
  • 8. Moscow, Russia
  • 9. Houston, TX
  • 10. Amsterdam, Netherlands
Bharat Suneja

Bizarre RSS Feed issue with FeedBurner?

The site's having some issues with the Feedburner RSS feed— it's stuck in a time warp and refuses to move on from the post dated June 15th, 2008 (the one titled What is an Azalia controller?).
Every day it moves forward by one day, so we're at June 17 in Firefox today. You may or may not run into it. To see it for yourself, try visiting the RSS feed URL in Firefox and in Internet Explorer. IE shows the updated feed.

If you're using FireFox, please use the atom feed meanwhile.

Recent Posts

Thursday, July 24, 2008

In Exchange Server 2003/2000, expanding a Mailbox Database provides information about mailboxes in a database, last logon/logoff times and account(s) that logged on to mailboxes (see 'Displaying Client IP Address in Exchange System Manager' for details).

Screenshot: Store Logons
Figure 1: In Exchange 2003, the Logons node displays Store logon-related information. Click here to see a bigger screenshot.

In Exchange Server 2007, these details are not displayed in the EMC. These can be retrieved easily using the Exchange shell.

The Get-LogonStatistics cmdlet provides the following logon-related information.

AdapterSpeed :
ClientIPAddress :
ClientMode :
ClientName :
ClientVersion :
CodePage :
CurrentOpenAttachments :
CurrentOpenFolders :
CurrentOpenMessages :
FolderOperationCount :
FullMailboxDirectoryName :
FullUserDirectoryName :
HostAddress :
LastAccessTime :
Latency :
LocaleID :
LogonTime :
MACAddress :
MessagingOperationCount :
OtherOperationCount :
ProgressOperationCount :
RPCCallsSucceeded :
StreamOperationCount :
TableOperationCount :
TotalOperationCount :
TransferOperationCount :
UserName :
Windows2000Account :
ServerName :
StorageGroupName :
DatabaseName :
Identity :

The command can be constrained to a mailbox database (get-logonstatistics -Database "MyDatabase" | fl), a mailbox server (get-logonstatistics -Server "MyServer"), or a particular mailbox.

Mailbox information

In ESM, the Mailboxes node of a Mailbox Store displays mailbox-related information such as mailbox size, number of items, and last logon/logoff.

Screenshot: Mailboxes node in Exchange 2003 ESM
Figure 2: In Exchange 2003, the Mailboxes node displays mailbox-related information. Click here to see a bigger screenshot.

This information can be retrieved using the Get-MailboxStatistics cmdlet. It provides the following information related to a mailbox:

AssociatedItemCount :
DeletedItemCount :
DisconnectDate :
DisplayName :
ItemCount :
LastLoggedOnUserAccount :
LastLogoffTime :
LastLogonTime :
LegacyDN :
MailboxGuid :
ObjectClass :
StorageLimitStatus :
TotalDeletedItemSize :
TotalItemSize :
Database :
ServerName :
StorageGroupName :
DatabaseName :
Identity :

It can also be constrained to a -Database, -Server, or mailbox.

Now that we're dealing with the shell, besides these cmdlets' built-in filtering capabilities (Database, Server, or mailbox), you can use Powershell's where-object cmdlet to further filter the results based on the properties returned by each cmdlet. For example, to find out logon sessions from a particular IP address:

Get-LogonStatistics -Server "MyServer" | where {$_.ClientIPAddress -like "192.168.2.101"}

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Tuesday, July 08, 2008

In previous versions of IIS, the IUSR_MachineName account is created for anonymous authentication. This is an actual user account created on the server (a domain account can be used in domain environments), and like all user accounts— it has a SID, and an account password with the accompanying management costs and risks.

One of the resulting annoyances (for me): when you install IIS first and then change the computer name, the computer name and the MachineName in IUSR_MachineName account don't match.

IIS 7 gets rid of the IUSR_MachineName account in favor of a built-in IUSR account that's guaranteed to have the same SID on all computers. This ensures ACLs copied from one web server to another work, domain accounts are no longer required, and applications can be easily deployed across multiple web servers. The IIS_WPG group (for IIS Application Pool identities) is replaced by the built-in group IIS_IUSRS.

Note: The IUSR_MACHINENAME account isn't completely gone— it is used for anonymous authentication to FTP, and gets created if/when you install FTP.

More on the IIS team blog in 'Understanding the Built-In User and Group Accounts in IIS 7.0'

- Security identifiers
- Well-known security identifiers in Windows operating systems

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Thursday, July 03, 2008

 

Released: ISA 2006 Service Pack 1

Posted by Bharat Suneja at 4:25 PM
ISA Server 2006 SP1 has been released. SP1 brings some new features, and improvements such as support for SAN certificates. Download SP1.

New features:
  • Configuration Change Tracking: Registers all configuration changes applied to ISA Server to help you assess issues that may occur as a result of these changes.
  • Test Button: Tests the consistency of a Web publishing rule between the published server and ISA Server.
  • Traffic Simulator:Simulates network traffic in accordance with specified request parameters, such as an internal user and the Web server, providing information about firewall policy rules evaluated for the request.
  • Diagnostic Logging Viewer: Now integrated as a tab into the ISA Server Management console, this feature displays detailed events on packet progress and provides information about handling and rule matching.


Improvements for existing features:
  • Support for integrated NLB mode in all three modes, including unicast, multicast, and multicast with Internet Group Management Protocol (IGMP). Previously, ISA Server integrated NLB-supported unicast mode only.
  • Support for use of server certificates containing multiple Subject Alternative Name (SAN) entries. Previously, ISA Server was able to use either only either the subject name (common name) of a server certificate, or the first entry in the SAN list.
  • Support for KCD cross-domain authentication. Credentials from users located in a different domain than the ISA Server, but in the same Forest, can now be delegated to an internal published Web site by using KCD .
  • Support for client certificate authentication in a workgroup deployment. This removes the requirement to map each client certificate to an Active Directory® directory user account when forms-based authentication is used as the primary authentication method and client certificates are used as the secondary method.



SP1 fixes the following issues:
  • 894679 Users who do not have the appropriate permissions can receive restricted content from ISA Server 2004
  • 920913 Error message in response to some HTTP requests on client computers that are running ISA Server 2004 as a proxy server: "400 Bad Request"
  • 921944 A client computer takes longer than expected to connect to a Web site through an ISA Server 2004 Web proxy server
  • 922851 You receive a blank page when your Web browser submits a POST request to an ASP Web site over an ISA Server 2004 access rule that requires client authentication
  • 922899 An ISA Server 2004 Web chaining rule may not redirect requests to the specified port
  • 923318 Error message in SecureNAT clients after you configure a Web chaining rule to forward HTTP as HTTPS in ISA Server 2004: "The target principal name is incorrect"
  • 923322 A large file download fails when an ISA Server 2004 SOCKS client computer uses passive mode FTP
  • 923765 The Microsoft Firewall service stops responding to client computer requests and Event IDs 7034, 14057, and 1000 are logged after you publish an OWA server in ISA Server 2004
  • 923766 A client computer may not be authenticated by ISA Server 2004 when you use integrated Windows authentication
  • 924405 Client computers cannot download attachments when you use ISA Server 2004 or ISA Server 2006 forms-based authentication and run a third-party OWA add-in program to manage attachments
  • 925288 One or more published sites may stop being available if you create more than 300 Web site publishing rules in ISA Server 2006 Enterprise Edition
  • 928273 Users may receive slow responses when you enable the Cache Array Routing Protocol in ISA Server 2004, Enterprise Edition
  • 929818 You receive an error message when you try to install or to run Windows Vista: "The Software Licensing Service reported that the license is invalid"
  • 930415 You cannot apply an OWA Web publishing rule that redirects users who connect to the root of the OWA Web site to an internal folder by using ISA Server 2006
  • 933523 When an Internet Security and Acceleration Server 2004 client performs an action that uses the HTTP POST method, the action may be performed multiple times
  • 934022 An ISA Server 2004 downstream server does not reuse the TCP connections to a third-party upstream server
  • 935767 The authentication delegation in the existing Web publishing rules does not work after you upgrade ISA Server 2004 Enterprise Edition to ISA Server 2006 Enterprise Edition
  • 938465 Error message when you try to access Web sites through a downstream server after you enable hotfix 927265 on an upstream server that is running ISA Server 2004: "502 Proxy Error"
  • 938550 An update enables multicast operations for ISA Server integrated NLB
  • 940659 Error message when you try to visit a Web site that is published in ISA Server 2004: "HTTP error 500: network name no longer exists"
  • 940708 The "401 Authentication Required" response that is sent by a Web site is dropped when you use ISA Server 2004 as a Web proxy
  • 941162 In ISA Server 2006, you cannot set a session time-out for private computers in a Web listener that has the RSA SecurID authentication method configured
  • 941296 An ISA Server 2006 computer may stop responding under a heavy load
  • 941634 After an ISA Server 2006 application filter establishes an HTTP connection, the connection closes before it can be used, and a "0x80004001 (E_NOTIMPL)" status code is logged
  • 941870 Only 1,000 PPTP ports and 1,000 L2TP ports are open in Routing and Remote Access if the maximum number of VPN clients is set to more than 1,000 in ISA Server 2006
  • 942313 Web pages do not appear as expected when you publish a Web site by using a publishing rule in Internet Security and Acceleration (ISA) Server 2006
  • 942637 A user cannot access a Web site that is published in ISA Server 2006 by using Kerberos constrained delegation if the user is not in the same domain as the ISA Server computer
  • 942638 POST requests that do not have a POST body may be sent to a Web server that is published in ISA Server 2006
  • 943200 The Microsoft Firewall service stops unexpectedly on a computer that is running ISA Server 2004
  • 943212 You cannot filter the RPC traffic based on universally unique identifiers (UUID) by using an access rule in ISA Server 2006
  • 943214 When you publish a back-end ISA Server 2006 computer on a front-end ISA Server 2006 computer that faces the Internet, you cannot enable forms-based authentication on both computers
  • 944699 The Microsoft Firewall service stops unexpectedly if a Web filter is used on a computer that is running ISA Server 2006
  • 944764 Requests that have large request bodies may fail when you publish a Web site in ISA Server 2006
  • 944824 Stop error message on a computer that has ISA Server 2006 installed: You receive a "Stop 0x0000007f"
  • 945224 ISA Server 2006 may forward requests to an incorrect Web server when a client computer accesses Web sites that have different public names in the same session
  • 945524 Some Web servers that are published in ISA Server 2006 by using the Web Publishing Load Balancing feature may be incorrectly detected as unavailable at random times
  • 945814 Error message when you try to change the password of a user account even if you configure ISA Server 2006 to allow users to change their passwords
  • 945882 HTTP SEARCH requests that do not have a SEARCH body may be sent to a Web server that is published in ISA Server 2006
  • 947254 A computer that is running ISA Server 2006 may randomly stop routing packets from certain VPN clients or from certain VPN site-to-site networks
  • 947255 Packets from the branch office may not reach the destination servers in the central office over a site-to-site VPN connection that you create through ISA Server 2006
  • 947521 When HTTP compression is enabled in Web publishing rules in ISA Server 2006, the compression filter may be unable to handle HTTP responses
  • 948711 A report may not display HTTPS traffic in ISA Server 2006
  • 949628 The Microsoft Firewall service crashes randomly when you use ISA Server 2006 to publish a Web server by enabling forms-based authentication
  • 950139 The Microsoft Firewall service in ISA Server 2006 stops responding to client requests after you publish a Web server by using NTLM authentication delegation
  • 951508 When you use ISA Server 2006 to publish a Web server, and authentication delegation is enabled, some Web content may not be displayed correctly when a user accesses the published Web server
  • 951509 Users cannot access a Web site that is published in ISA Server 2006 if the Web site accepts only the SPNEGO authentication package
  • 950150 Error message when you open a .gz file that you downloaded through an ISA Server 2004 Web proxy server: "Invalid archive directory"
  • 952675 You cannot log on to a local intranet site that you publish by using ISA Server 2006 when there are multiple user accounts that have the same account name in different domains

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Thursday, June 19, 2008

When ISA Server 2006 SP1 rolls out this summer, there will be some cool new features to look forward to, including support for SAN certificates.

Having started using Proxy Server 1.0 (I know... hold on to your comments for now.. :) back in the days, I turned away from ISA's predecessor(s) for a few years to engage with what I thought were better options at that time— "dedicated" hardware firewalls. Not too long ago, I started using ISA again, and became a convert with ISA 2006. It made "publishing" (am I the only one who finds the phrase "publishing to the internet" amusing?) Exchange services such as OWA, EAS, Outlook Anywhere, and SMTP secure and relatively effortless.

If you have ISA 2006 deployed with Exchange Server 2007, you're probably looking forward to SP1 as well for its SAN certificate support. Check out the other cool features in this post on the ForeFront TMG (ISA) team blog: ISA Server 2006 Service Pack 1 Features.

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Tuesday, May 20, 2008

Another frequently asked question about SMTP mail - how can I remove internal host names and IP addresses from outbound internet mail? More often than not, this results from the belief that somehow if the outside world finds out an organization's internal IP addresses and host names, it makes the organization vulnerable. Auditors love to point this out for some reason. Perhaps it's a part of a checklist written by a security expert at some law firm somewhere, and given the viral nature of checklists it's all over the place!

Let's take a look at what we're talking about here. As a message makes its way from one server to another, it may be handled by more than one SMTP hosts. Each host adds a RECEIVED header at the beginning of message headers, leaving a trace of where the message has been and when (a timestamp).

Here are headers from a message received from Dell. (Unnecessary headers removed).

Received: from smtp.easydns.com (205.210.42.52) by exchange.somedomain.com
(192.168.2.171) with Microsoft SMTP Server id 8.1.240.5; Mon, 19 May 2008
03:12:46 -0700
Received: from mh.dell.m0.net (mh.dell.m0.net [209.11.164.66]) by
smtp.easydns.com (Postfix) with ESMTP id 647C222914 for ;
Mon, 19 May 2008 06:14:46 -0400 (EDT)
Received: from [192.168.138.130] ([192.168.138.130:57330]
helo=fc13a1.dc1.prod) by oms1.dc1.prod (ecelerity 2.1.1.24 r(19486)) with
ESMTP id 3B/AF-18306-11351384 for ; Mon, 19 May 2008
03:14:41 -0700

Message-ID: <14154167762.1211192081379@delivery.net>
Date: Mon, 19 May 2008 03:14:41 -0700
From: Dell Small Business
Reply-To:
To:
Subject: $429 desktop, plus new laptops. Hurry and shop now.
Errors-To: dell@smallbusiness.dell.com
Return-Path: dell@smallbusiness.dell.com

These headers can be used to determine the path taken by a message— useful information for troubleshooting and preventing message loops.

What the standards say
Let's take a look at what the standards say. RFC 2821 says (capitalization of words as it appears in the RFC, emphasis added):
4.4 Trace Information

When an SMTP server receives a message for delivery or further processing, it MUST insert trace ("time stamp" or "Received") information at the beginning of the message content, as discussed in section 4.1.1.4.

This line MUST be structured as follows:

- The FROM field, which MUST be supplied in an SMTP environment, SHOULD contain both (1) the name of the source host as presented in the EHLO command and (2) an address literal containing the IP address of the source, determined from the TCP connection.
and prohibits removing received headers (repeatedly). One example:
An Internet mail program MUST NOT change a Received: line that was previously added to the message header. SMTP servers MUST prepend Received lines to messages; they MUST NOT change the order of existing lines or insert Received lines in any other location.
More secure?
Should you remove these headers, and "hide" internal hosts and IP addresses? Is it really a security risk?

There are many opinions about security through obscurity, but if your security relies on hiding internal hostnames and IP addresses, you probably have other things to worry about.

Steve Riley, Senior Security Strategist at Microsoft, says:
In general, you can’t achieve any additional security by trying to hide things that weren’t designed to be hidden. IP addresses, wireless SSIDs, hostnames—these are all identifiers, and by definition, an identifier is intended to be known. Efforts to hide them generally fail, because the thing that the identifier points to still exists! Determined attackers will find the thing regardless of what you name it.
Microsoft does not remove internal message routing headers. Nor do Dell (as the message headers in the example above reveal), HP, and many other large organizations.

In many ways, the issues faced are similar to changing fqdn on SMTP Virtual Server/Receive Connector. Even if you make these changes, at least one internal hostname is likely to be revealed by the Message-ID (read "Masquerading SMTP Virtual Servers: Changing the fqdn and masquerade domain").

Nevertheless, many organizations may have a legitimate need to cleanse outbound mail of internal host names and IP addresses, and you probably don't want to invite adverse remarks in an IT or compliance audit (should you find such a requirement on the auditor's checklist).

How to remove Received headers in Exchange Server 2007
Exchange Server 2007 offers an easy way to accomplish this. If your transport server sends outbound email directly using DNS lookup, or delivers to a smarthost without authentication, simply remove the Ms-Exch-Send-Headers-Routing permission assigned to Anonymous Logon— a well-known security principal that refers to anonymous users, as shown below:

Get-SendConnector "Connector Name" | Remove-ADPermission -AccessRight ExtendedRight -ExtendedRights "ms-Exch-Send-Headers-Routing" -user "NT AUTHORITY\Anonymous Logon"

What's your take?
Does your organization remove internal Received headers? What are the reasons cited? Does removing internal received headers make your organization more secure? Feel free to leave a comment and share your opinion about this.

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Saturday, March 29, 2008

 

PWN to OWN Contest: Vista gets compromised

Posted by Bharat Suneja at 9:57 AM
Update on the PWN to OWN contest at the CanSecWest conference. After the MacBook Air got compromised in 2 minutes, Shane Macaulay claimed victory over the Fujitsu laptop running Windows Vista. Yes, Windows Vista was compromised at the tail end of Day 2, at 7:30 p.m., thanks to a vulnerability in Adobe Flash.

More in PWN to OWN: Final Day (and another winner!) on TippingPoint.

The list of conference sponsors includes both Adobe and Microsoft.

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Friday, March 28, 2008

 

Mac, meet PC: PC, the Mac's already hacked!

Posted by Bharat Suneja at 7:56 AM
The Event: CanSecWest's PWN 2 OWN contest, Vancouver, Canada
The Contenders: Mac OS X Leopard, Microsoft's Windows Vista, and Linux.
The Challenge: Compromise the OS
The Prize: $10,000 + laptop
The Winner: Charlie Miller

Apparently, the OS that's safer by design is the first to get compromised, after the rules were relaxed a little bit. 2 minutes is all it took, according to a report in InfoWorld (yes, still one of my favorite tech news sources). Excerpt:
Contest rules state that Miller could only take advantage of software that was pre-installed on the Mac, so the flaw he exploited must have been accessible, or possibly inside, Apple's Safari browser.
And:
Shane Macaulay, who was Dai Zovi's co-winner last year, spent much of Thursday trying to hack into the Fujitsu Vista laptop, at one point rushing back to his Vancouver area home to retrieve a file that he thought might help him hack into the system.

But it was all in vain.
More in Gone in 2 minutes: Mac gets hacked first in contest on InfoWorld.com.

This comes little over a week after Apple released what is labeled a massive patch, a monster patch, a mega-update, or a mega-monster security update by the media (Yes, that makes me feel like Jon Stewart now). The patch contains 90 fixes according to these reports.

Last year's contest winner, Dino Dai Zovi, exploited a vulnerability in Apple's QuickTime to take home the prize.

Gloat not, Windows Vista and Linux. You are expected to be hacked by today— and when that happens, it will be further proof that vulnerabilities exist in all systems. That's the nature of software. When it comes to millions of lines of code, "bug-free" and "vulnerability-free" software is a myth. What really matters is how easily these can be exploited, how quickly the vendor responds and releases patches to fix vulnerabilities.

As far as Windows Vista is concerned, it has an enviable track record so far.

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Wednesday, March 12, 2008

India's half a million BlackBerry users may have to live with the prospect of the Indian government having easy access to their wireless communication.

India says it needs access to RIM's encryption algorithms, used to encrypt email sent and received by BlackBerry smartphones, to fight terrorism. The Indian government is delaying a license to offer BlackBerry services to wireless carrier Tata Teleservices, and may cancel the licenses already issued to other Indian wireless carriers— Vodafone Essar, Bharti Telecom and Reliance Communications, if RIM doesn't comply by March 31st. The Information Technology Act of 2000 provides the government of India the right to intercept electronic communications for security reasons.

It's no secret that terrorists are increasingly using the internet and email to communicate. Bringing BlackBerry handhelds under the scope of lawful interception shouldn't come as a big surprise, but it does pose interesting questions for RIM.

The Department of Telecom's intent and its notice to carriers is anything but abrupt. The DoT had requested access some time last year. The March 31st deadline is an extension to the earlier deadline of December 31st. DoT officials are meeting with carrier execs and RIM officials to resolve the issue.

More in "BlackBerry under security scrutiny in India" on washingtonpost.com.

What makes the whole episode more interesting are reports that the Indian government wants significantly weaker encryption keys to be used across the board. If true, this could make security of online banking and e-commerce transactions questionable, and may even pose threats to India's growing outsourcing sector. ISP Association of India President Rajesh Chharia says "Routine check-ups are fine with us since the issue is one of national security. All ISPs must, and will, cooperate. What is of concern, though, is the fact that we have been asked to reduce the encryption from 128-bit to 40-bit, which is ridiculous.” (More in "BlackBerry security issue makes e-com insecure").

As similar incidents involving India's bureaucracy have proven in the past, better sense does eventually prevail in India (Read previous post: "Update: India blocks access to blogs"), but not before giving massive doses of anxiety attacks to those concerned.

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Monday, March 03, 2008

Exchange Server 2007 allows easier delegation of administration responsibilities, based on the following predefined administration roles:
1) Exchange Organization Administrator
2) Exchange Server Administrator
3) Exchange Recipient Administrator
4) Exchange Public Folder Administrator and
5) Exchange View Only Administrator.


Figure 1: Exchange Server 2007 allows delegation of administrative responsibilities

The delegation wizard in the EMC allows you to delegate the Recipient Administrator role for the entire Organization, but doesn't allow more granular delegation at the Domain or OU level.

More about the Exchange Recipient Administrator role

Security principals that have the Exchange Recipient Administrator role delegated get membership of the Exchange View Only Administrators role. Additionally, they are assigned:
- Read access to all the Domain Users containers in AD (in domains where Setup /DomainPrep has been run)
- Write access to all the Exchange-specific attributes in those domains

When delegating the Exchange Recipient Administrator role using the Exchange console or the Add-ExchangeAdministrator command in the Exchange shell, all you're doing is adding the security principal (user/group) to Exchange Recipient Administrators, a (Universal) Security Group in the Microsoft Exchange Security container in AD.

For more details about Exchange Server 2007 permissions, refer to "Configuring Permissions in Exchange Server 2007".

Here's how you can delegate recipient administration for an OU.
Exchange Organization: E12Labs
Domain: E12Labs.com (DC=E12Labs,DC=com)
OU: San Francisco (OU=San Francisco,DC=E12Labs,DC=com)
User: foo (Best Practice: Assign permissions to Security Groups)

1 Allow generic read permission for objects in the OU:

Add-ADPermission -Identity "ou=San Francisco,dc=E12Labs,dc=com" -User "E12Labs\foo" -AccessRights GenericRead

2 Allow ReadProperty and WriteProperty permissions on Exchange-related attributes for objects in the OU

Add-ADPermission –Identity "ou=San Francisco,dc=E12Labs,dc=com" –User "E12Labs\foo" -AccessRights ReadProperty, WriteProperty -Properties Exchange-Information, Exchange-Personal-Information, legacyExchangeDN, displayName, adminDisplayName, displayNamePrintable, publicDelegates, garbageCollPeriod, textEncodedORAddress, showInAddressBook, proxyAddresses, mail

Property Sets in Active Directory

Exchange-Information and Exchange-Personal-Information are property sets - a number of related properties grouped together. Assigning permissions on a property set results in a single ACE in DACLS, making them much smaller and faster to process.

Exchange Server 2003 adds Exchange attributes to the Public Information and Private Information property sets that exist in Active Directory.

Exchange Server 2007 does not rely on these existing AD property sets, but creates 2 of its own. If deploying in an existing Exchange 2003 Forest, Exchange Server 2007 removes the Exchange properties added to the AD property sets and adds them to the new Exchange 2007 property sets. The Exchange-Information property set has 105 properties. Exchange-Personal-Information has 7. More information about the Exchange Server 2007 property sets and which properties are included in them can be found in "Property Sets in Exchange 2007".

3 Allow creation and management of Dynamic Distribution Groups in the OU
Exchange Server 2007 RTM:

Add-ADPermission -Identity "ou=San Francisco,dc=E12Labs,dc=com" -User "E12Labs\foo" -AccessRights GenericAll –InheritanceType Descendents -InheritedObjectType msExchDynamicDistributionList

Add-ADPermission -Identity "ou=San Francisco,dc=E12Labs,dc=com" -User "E12Labs\foo" -AccessRights CreateChild, DeleteChild -ChildObjectTypes msExchDynamicDistributionList

Exchange Server 2007 SP1:

Add-ADPermission -Identity "ou=San Francisco,dc=E12Labs,dc=com" -User "E12Labs\foo" -AccessRights CreateChild, DeleteChild -ChildObjectTypes msExchDynamicDistributionList

4 Allow permission to access RUS:

Add-ADPermission -Identity "CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=E12Labs,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=E12Labs,DC=com" -User "E12labs\foo" -InheritedObjectType ms-Exch-Exchange-Server -ExtendedRights ms-Exch-Recipient-Update-Access -InheritanceType Descendents

5 Allow permission to update Address Lists and Email Address Policies:

Add-ADPermission –Identity "CN=Address Lists Container,CN=E12Labs,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=E12Labs,DC=com" –User "E12Labs\foo" -AccessRights WriteProperty -Properties msExchLastAppliedRecipientFilter, msExchRecipientFilterFlags

Add-ADPermission –Identity "CN=Recipient Policies,CN=E12Labs,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=E12Labs,DC=com" –User "E12Labs\foo" -AccessRights WriteProperty -Properties msExchLastAppliedRecipientFilter, msExchRecipientFilterFlags

6In addition to these Active Directory permissions, recipient administrators also need Exchange View Only Administrator permission on the Exchange Organization. Use the following command to assign it:

Add-ExchangeAdministrator "E12Labs\foo" -Role ViewOnlyAdmin

A script for SP1: If you're on Exchange Server 2007 SP1, a script written by Ross Smith IV makes delegating recipient administration permissions on an OU a simple task accomplished quickly (No, it's not for Exchange Server 2007 RTM). The script - ConfigureSplitPerms.ps1, resides in the \Scripts folder in the Exchange Server install path. Usage:

.\ConfigureSplitPerms.ps1 -user "MyDomain\foo" -identity "OU=San Francisco,DC=ExchangeLabs,DC=net"

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Thursday, February 28, 2008

 

InfoWorld's campaign to "Save Windows XP"

Posted by Bharat Suneja at 3:00 PM
I've been an avid reader of InfoWorld for as long as I can remember. It is one of the finest trade publications out there. In case you've missed it, they've been running an online campaign to "save Windows XP". A few weeks ago, they announced that 75,000 XP users had signed up for it (Read "75,000 demand Microsoft keep Windows XP going"). If you look at the numbers, it's a tiny fraction of the overall number of Windows XP users.
Update: The last update from InfoWorld is dated Feb. 28th- the number reported is 97,280.

InfoWorld says its readers want Microsoft to keep selling and supporting Windows XP indefinitely. Given that Windows XP was released back in 2001 - almost 7 years ago, is Microsoft wrong in ending support for a product that has certainly lived past its shelf life? If you work in the software industry, dealing with today's rapid-fire software releases, it's hard to imagine supporting something that old!

From Save Windows XP! The clock is ticking:
Millions of us have grown comfortable with XP and don't see a need to change to Vista. It's like having a comfortable apartment that you've enjoyed coming home to for years, only to get an eviction notice. The thought of moving to a new place -- even with the stainless steel appliances, granite countertops, and maple cabinets (or is cherry in this year?) -- just doesn't sit right. Maybe it'll be more modern, but it will also cost more and likely not be as good a fit. And you don't have any other reason to move.
Reading the above, you get the impression that somehow Microsoft can and is actually forcing existing users of Windows XP to stop using that OS past June 30th, 2008. That is completely untrue! All Microsoft is saying is - this product has reached its end of life, and we will stop selling it by that date. It really has no impact on existing users who want to continue using it.
The fact is: your licensed copy of Windows XP doesn't come with an expiration date.
If you have an XP license today, or buy one by that date, you can install it on any computer you buy two, five, ten, or any number of years from now, provided the hardware is compatible. This does not apply to OEM licenses sold to computer manufacturers like Dell, HP, or Gateway - which are tied to the computer they ship with.

Microsoft's Windows Lifecycle Policy: Selling Windows, And Supporting It

Microsoft's Windows Life-Cycle Policy states that:
- Direct OEM and retail licenses will be sold till June 30th, 2008.
- System Builder licenses will be available till January 31st, 2009.
- The policy further states that "licenses will continue to be available through downgrade rights available in Volume Licensing programs after end of general availability".

Though Microsoft will stop selling Windows XP based on the above timeline, support for the operating system isn't going to end when that happens. Microsoft Support Lifecycle explains Microsoft's support policies, including what mainstream and extended support mean. According to the Microsoft Support Lifecycle for Windows XP:
- Mainstream support will end on April 14th, 2009.
- Extended support will be available for five years from that date, till April 8th, 2014!

For a product with General Availability dating back to December 31, 2001, Windows XP doesn't seem like a product that's being retired prematurely.

On a second look, InfoWorld's case isn't so much for Windows XP, as it is against Windows Vista. Running alongside the Save Windows XP articles: Why people hate Vista and Time to dump Windows?.
Update: To be fair to InfoWorld, they've also recently published "How to deploy Windows Vista".

A quick look at some of the arguments against Windows Vista:

Vista a resource hog? Yes, Windows Vista requires more resources - and the last time I looked around, today's PC hardware was more than adequately equipped for Vista. Most decently-configured laptops, including the entry-level ones that sell for way under a thousand bucks, ship with dual-core processors and 2 Gigs of RAM. And under a thousand bucks get you what can be considered a state-of-the-art quad-core desktop with 3-4 gigs of RAM. In fact, a few weeks ago I was pleasantly surprised by the price of 4 Gigs of RAM for my laptop - $79!

Vista isn't designed to run on yesterday's hardware, and there's no reason for Microsoft to be apologetic about it. It's the same hardware + OS + apps purchase cycles we've been used to for a long time now. What do you want to buy the next time your three or five-year-old computer dies, or you simply get fed up with it and want something new? Do you look for a single-core Pentium 4 processor that can run Windows XP well - assuming you can find one? (As a sidenote, I'm writing this on a single-core Pentium 4 box running Windows Vista, and doing fine, thank you! I also had a 400-Mhz (yes, Mhz... ) PIII box with all of 256 Mb RAM running Windows Server 2003, AD, and Exchange Server 2003 for years, till it died last year.)

It's the same cycle as buying microwaves or vacuum cleaners - they get old, stop working, or simply get in the way and impair users' productivity. When that happens, you go out and buy a new one, generally in the same price range or perhaps a little cheaper, but something that has all (or most of) the bells and whistles - the right stickers, logos, and features that a contemporary microwave or vacuum cleaner would have.

PCs are no different. In fact, thanks to Murphy's Law and the underlying technology breakthroughs, we generally get a lot more bang for our buck with every upgrade cycle.

If your microwave/vacuum cleaner/PC isn't broken yet (or more importantly, if you aren't fed up with it, and it isn't getting in your way), there's really no reason to buy a new one. Unless you like buying new computers every couple of years, or sooner, and can afford to do so.

Drivers: Yes, drivers. Somehow Microsoft is to blame for the perceived lack of drivers. Personally, I haven't come across any piece of hardware recently - a display card, printer, or other peripheral that does not sport a driver for Windows Vista, or otherwise caused any compatibility issues. For most part, everything works out of the box.

Security: Security, you say. Seems like Windows Vista has proved its credentials on that front. Agreed, UAC can be a little annoying at times, and gives Apple a great talking point for its commercials, but that doesn't take away from the fact that Vista is a much more secure OS than Windows XP ever was. In fact, Vista does very well on this front compared to other OSes, including Apple's. Read previous post about the 6-month vulnerability report "Numbers talk: Vista most secure OS of all?", or grab the more current one-year vulnerability report.

User Account Control

It is easy to criticize the UAC feature without getting a good understanding of what it does and the problem it's intended to solve for IT departments. After years of extolling the virtues of not logging on using an account with administrator privileges for day-to-day stuff, I love UAC! It ensures administrator privileges are not available to your session all the time - even if you're logged in as an administrator. Not only does this protect computers from malicious code, it also protects users from themselves. When you do need to perform a task that requires administrator privileges, you are prompted for it.

Security has a cost - often measured in user inconvenience. Many security products and features come with some inconvenience to users. The argument shouldn't be about whether to have UAC, but about the ability to fine-tune it to an organization's security requirements. Arguably, this could be refined further to allow more granular control, but being aware of the options already available, including the ability to turn it off using Group or Local Policies helps.

The following graph from the one-year vulnerability report shows vulnerabilities found in Windows Vista, Windows XP, Red Hat Linux, Ubuntu, and OS X in the first year of release. It's clear what the numbers reveal, though many of us often tend to get more influenced by anecdotal evidence- particularly in this context.

Graph: Vulnerabilities compared
Figure 1: Vulnerabilities found in Windows Vista in the first year of its release compared to other operating systems

Vista is slow: One of the more common arguments against Vista, slow is a relative term. Slow as compared to what? Running on the same hardware as my Windows XP computer, performing the same tasks, I haven't noticed this slowness. If you benchmark performance results, Vista can be proven to be slower than anything. The questions to ask: - When was the test conducted? What version of Vista? What kind of hardware? What kind of applications? And more importantly, how slow was it really?

Yes, you may lose a few percentage points in performance, but there are gains in usability and new features.

I wouldn't blame InfoWorld for wanting to ride the "Bash Vista" bandwagon - it's fashionable to do so. To our relief, there are some saner voices out there. Like InfoWorld's own columnist, J. Peter Bruzzese. Peter writes in his Enterprise Windows column - titled "Save XP? Why bother?":
The fact of the matter is, Vista is incredible. I've been working with it since Beta 3, and I won't return to that cartoon-looking XP for anything. Not only is it more secure than XP, it includes a host of invaluable new tools and applications (more on those in a bit).

Yes, Vista is more resource-intensive than XP. Yes, upgrading from XP to Vista requires putting some cash on the table. But Vista beats XP hands down, and the Save XP campaign amounts to unfairly criticizing Microsoft for adhering to a core capitalist practice: retiring an old product to sell newer, better ones.

That "yucky Windows"

My 4-year old son agrees with Peter's assessment about XP. For the few days that I had a loaner Media Center PC running Vista, not only did the little one get quite comfortable with it, he fell in love with it. When it was time to get my XP Media Center PC back from repairs, there were angry protests about having to deal with the "yucky Windows" (that would be XP!) that one doesn't ordinarily associate with someone his age.

Though a lot of it has to do with the aesthetics - the "X button that glows" when he wants to close a window and Gadgets that expand his vocabulary - isn't the UI and usability a big reason why we choose to use Windows and the exact topic Apple can't stop talking about when it comes to OS X?


Figure 2: Windows Vista's Media Center interface

I finally upgraded the box - the last one I had with Windows XP, to Windows Vista on the last day of 2007. The delay was in large part because of the vendor - name withheld, mislabeled the TV tuner driver, causing a lot of confusion amongst its customers.

As a sidenote to this sidenote, Media Center is probably the most mission-critical app of all, as far as end-users/home users are concerned... an email outage at work is probably something you can survive and live to tell the tale. A "TV outage" at home is an event unmatched in its criticality, perhaps deserving a designation higher than P1/S1.

What kind of supporters is InfoWorld touting with its Save XP campaign? Let's turn again to Peter's column:
If you read a lot of the comments that people have been adding on the Save XP pages, you might note that an awful lot of people say, "Go to Linux," or "That's why I use Linux." You know, I've never heard a Mac user complain about Apple or their Mac, nor a Linux user complain about Red Hat or whatever version they are using. That's not to say they don't have problems; they just keep the discussion among themselves. But they are having a field day watching Microsoft users fight each other. Ever think they're the ones stirring up this whole Save XP campaign?
Come on InfoWorld, it's time to give up the skepticism, and that childish campaign. Users are moving to and using Windows Vista, and that will only accelerate going forward, now that SP1 is here. Users and organizations who want to continue using Windows XP can take their own time to upgrade - Windows XP will still be available for the foreseeable future, and supported for a much longer period (as stated in Microsoft's product lifecycle policies referenced in this post).

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Tuesday, February 05, 2008

In "HOW TO: Grant Full Mailbox Access permission", we saw how to assign and view mailbox permissions, including Full Mailbox Access. Here's how you can get a list of mailboxes with explicitly-assigned (i.e. not inherited) Full Mailbox Access permissions.

Instead of running this against all mailboxes in the Organization, it makes sense to filter it against a sub-set of mailboxes.

Filtering mailboxes returned by Get-Mailbox

Mailboxes returned by the Get-Mailbox command can be filtered using -Server, -Database, -RecipientTypeDetails, and -OrganizationalUnit parameters. Note, the -Filter parameter can also be used and allows granular filtering of mailboxes that are returned, based on a number of filterable properties.

In this example, we use the -Server parameter to filter mailboxes on a particular server, and pipe it to the Get-MailboxPermission command:

Get-Mailbox -Server "e12postcard" | Get-MailboxPermission

This produces a long list of permissions - inherited and assigned explicitly to the mailbox(es).

Let's filter the above to reveal only the explicitly assigned permissions:

Get-Mailbox -Server "e12postcard" | Get-MailboxPermission | where { $_.IsInherited -eq $false }

The output shows all explicitly-assigned permissions, including the permissions assigned to the mailbox owner (NT AUTHORITY\SELF). Not quite what we want! Let's filter that out:

Get-Mailbox -Server "e12postcard" | Get-MailboxPermission | where { ($_.IsInherited -eq $false) -and -not ($_.User -like "NT AUTHORITY\SELF") }

Now we have a list of all mailboxes with explicitly assigned permissions.

We can filter this further to list only the ones that have Full Mailbox Access permission assigned:

Get-Mailbox -Server "e12postcard" | Get-MailboxPermission | where { ($_.AccessRights -eq "FullAccess") -and ($_.IsInherited -eq $false) -and -not ($_.User -like "NT AUTHORITY\SELF") }

Similarly, you can filter users that have other mailbox permissions assigned, such as SendAs, DeleteItem, ReadPermission, ChangePermission, ChangeOwner, or ExternalAccount.

Related Posts:
- HOW TO: Grant Full Mailbox Access permission
- HOW TO: Assign SendAs right using Exchange shell

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Monday, January 28, 2008

Exchange Server 2007 issues itself a self-signed certificate for use with services like SMTP, IMAP, POP, IIS and UM. The certificate is issued for a period of one year.

The self-signed certificate meets an important need - securing communication for Exchange services by default. Nevertheless, one should treat these self-signed certificates as temporary. It's not recommended to use these for any client communication on an ongoing basis. For most deployments, you will end up procuring a certificate from a trusted 3rd-party CA (or perhaps an internal CA in organizations with PKI deployed).

However, should you decide to leave the self-signed certificate(s) on some servers and continue to use them, these need to be renewed - just as you would renew certificates from 3rd-party or in-house CAs.

1 To renew the certificate for server e12postcard.e12labs.com, a server with CAS and HT roles installed:

Get-ExchangeCertificate -domain "e12postcard.e12labs.com" | fl

Note the services the certificate is enabled for (by default: POP, IMAP, IIS, SMTP on CAS + HT servers). Copy the thumbprint of the certificate.

Get a new certificate with a new expiration date:

Get-ExchangeCertificate -thumbprint "C5DD5B60949267AD624618D8492C4C5281FDD10F" | New-ExchangeCertificate

If the existing certificate is being used for SMTP, you will get the following prompt:

Confirm
Overwrite existing default SMTP certificate,
'C5DD5B60949267AD624618D8492C4C5281FDD10F' (expires 8/22/2008 7:20:34 AM), with certificate '3DA55740509DBA19D1A43A9C7161ED2D0B3B9E3E' (expires 1/28/2009 7:37:31 AM)?
[Y] Yes [A] Yes to All [N] No [L] No to All [S] Suspend [?] Help
(default is "Y"):

Type y to continue. A new certificate is generated.


Thumbprint   Services   Subject
----------   --------   -------
3DA55740509DBA19D1A43A9C7161ED2D0B3B9E3E   .....   CN=E12Postcard

The new certificate is generated and enabled. Examine the new certificate:

Get-ExchangeCertificate -thumbprint "3DA55740509DBA19D1A43A9C7161ED2D0B3B9E3E" | fl

1 The old certificate is enabled for IIS, POP, IMAP and SMTP. The new certificate generated using the above command is enabled only for POP, IMAP and SMTP - IIS is missing.

To enable the certificate for IIS:

Enable-ExchangeCertificate -thumbprint "3DA55740509DBA19D1A43A9C7161ED2D0B3B9E3E" -services IIS

This enables the certificate for IIS (in addition to any other services it may already be enabled for - it adds to existing values of the services property).

1 Test services are working with the new certificate. If it works as expected, the old certificate can be removed:

Remove-ExchangeCertificate -thumbprint "C5DD5B60949267AD624618D8492C4C5281FDD10F"

Related posts:
- Outlook Anywhere and Exchange's Self-Signed Certificate
- Which name should I use as Common Name for my UC certificate?
- DigiCert: A Certificate Authority with excellent customer service

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Wednesday, January 09, 2008

An Exchange Server message routing myth forever being propagated (including by me):
If 2 SMTP Connectors (or Send Connectors in case of Exchange Server 2007) exist, one with a more specific address space, like exchangepedia.com, and one for a more generic address space like *, messages are always routed over the Connector with the more specific address space.
Now, generally that rule of thumb works for most purposes, until you consider restrictions on Connectors. These include:
Connector Scope: (Entire) Organization, or the Routing Group (to which the Connector belongs or is homed to)
Message Size restrictions: To prevent messages over a certain size from being routed over a Connector
Delivery Restrictions: To allow/prevent messages from particular senders from being routed over a Connector (Exchange Server 2003/2000)

Screensot: Content Restrictions on Exchange Server 2003/2000 SMTP Connectors
Figure 1: Content Restrictions on a SMTP Connector, including message size limit

Scenario:
You want to prevent users from sending messages over 100 Kb to exchangepedia.com.
- Connector1 for address space exchangepedia.com, message size restriction of 100Kb.
- Connector2 for address space *, no message size restrictions.
Result:
- Messages for exchangepedia.com recipients with a message size that is under the 100kb limit are routed over Connector1.
- Messages for exchangepedia.com recipients with a message size of over 100kb are routed over Connector2 with the generic address space of *. Connector1 with more specific address space of exchangepedia.com is never considered.

If you want to limit messages sent to exchangepedia.com to only 100kb, you cannot do it using the configuration in the above scenario.

From Exchange Server 2007 documentation:
Routing to External Domains -> Selecting the Routing Path to an External Recipient):
If more than one Send connector is configured to have an address space that meets the routing requirements for an external recipient, Exchange 2007 routing will select a single connector through which to route the message. The selected connector must meet the message size constraints. After Exchange 2007 has eliminated all connectors that have prohibitive message size restrictions, routing applies the following criteria to determine to which connector it will route:

From the list of all Send connectors and foreign connectors that are configured in the Exchange organization, it narrows the list to connectors that satisfy all the following criteria:

- In the scope for the local server
- Enabled
- With an address space that matches the recipient's e-mail domain

From the resulting list, select the connector with the most specific address space match. No matching connectors may be found.
Maybe an Exchange Server 2007 change, you wonder. Not quiet - Exchange Server 2003 behaves similarly.

From Exchange Server 2003 documentation:
Exchange Server 2003 Message Routing -> Routing Path Selection Process
It determines all connectors to the message destination in the organization topology, and then analyzes message characteristics and connector restrictions to exclude all those connectors that must not be used to transfer the message.
In a nutshell: Connector selection happens after restrictions are checked.

Which Connector? Determining the Send Connector used in Exchange Server 2007 is quiet easy - if using different fqdns on a Send Connector, you can simply check the Received headers; or you can look at the SMTP logs (read previous post "Exchange Server 2007: Logging SMTP Protocol Activity"). In Exchange Server 2003, you can bump up the diagnostics logging on MSExchangeTransport -> Routing Engine/Service. Exchange logs Event ID 984, which provides details about message routing, including the Connector selected.

In the following screenshots, we see 2 different SMTP Connectors being selected for 2 messages to the same destination - the smaller message uses the Connector with the specific address space - exchangepedia.com, which routes the message to a smarthost. The larger message that exceeds that Connector's message size limit is routed using the Connector for address space *, which routes the message using DNS to lookup the MX record(s) for exchangepedia.com.


Figure 2: With Diagnostics Logging enabled, Exchange Server 2003 logs Event ID 984, which shows Connector selected (for a small message under 100kb in this case). The message is delivered to the Smarthost specified in the Connector.


Figure 3: Event ID 984 shows the Connector for generic address space * selected for a larger message (over 100kb in this case). Message is delivered using DNS lookup.

Unintended consequences? The implications aren't pretty, specially when you consider scenarios where one uses a SMTP Connector for a particular address space to enforce TLS (perhaps one of the biggest reasons why messages should never be routed over a Connector with a generic address space if a Connector for a specific address space exists). If I enforce message size restrictions on my Connector with TLS enabled, larger messages can and will be transmitted using the generic Connector that does not use TLS. Now we have the larger message(s) traveling over potentially unsecured SMTP sessions.

What about Delivery Restrictions? For Exchange Server 2003, the same is true for Delivery Restrictions. If the Connector for exchangepedia.com has Delivery Restrictions to prevent Joe Adams from sending messages to Exchangepedia, the message routes over the generic Connector for * - effectively flushing such restrictions down the tube. Restrictions on Connectors with more generic address space are a different story - if Joe has Delivery Restrictions on the * Connector, he cannot send internet mail.

The first task of the Routing Engine/transport should be to check if Connectors with more specific address spaces are available. If it finds any, there is no reason to exclude these from the routing decision. Any restrictions on that Connector exist for a purpose - to restrict message sizes, or to prevent certain users from sending to particular domains using Delivery Restrictions. By excluding Connectors with restrictions from the routing calculation, we're saying routing the message is more important than enforcing those restrictions. As a result, by routing the message over generic Connectors, other requirements for mail delivery to that address space, such as those mentioned above and other available Connector settings, may not be applied.

Related Posts:
- HOW TO: Prevent a user from sending and receiving internet mail
- Exchange Server 2007: Setting Message Size Limits
- Masquerading SMTP Virtual Servers: Changing the fqdn and masquerade domain

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Wednesday, December 05, 2007

 

Schwartz: Zero tolerance for zero retention

Posted by Bharat Suneja at 8:23 AM
On the first anniversary of the Federal Rules for Civil Procedure (PDF), which provide guidelines for e-discovery, InfoWorld editor Ephraim Schwartz discusses the implications in his Reality Check column. Read more in "Zero tolerance for zero retention".

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Thursday, November 29, 2007

 

Released: ForeFront Security for Exchange SP1

Posted by Bharat Suneja at 7:15 PM
ForeFront Security for Exchange SP1 follows Exchange Server 2007 SP1 out the door. FSE SP1 is compatible with Exchange Server 2007 SP1. It includes support for Windows Server 2008, IPv6, and improved content filtering.

Exchange Server 2007 SP1 and ForeFront Security for Exchange

- Before you upgrade Exchange Server 2007 to SP1, make sure you either upgrade ForeFront Security for Exchange to SP1, or uninstall it.
- If ForeFront Security for Exchange is upgraded to SP1, you must stop all ForeFront services before upgrading Exchange Server 2007 to SP1.

Download it here.

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