Virtualization, Cloud, Infrastructure and all that stuff in-between

Final day of this TechEd.

First-up a session with Mark Minasi on 2 of Vistas least understood security features, User Account Control (UAC) and Windows Integrity Levels (WIL)

Mark is another of the popular TechEd regulars and always gives a good show, he’s written many good books which I own 🙂

the key points for me were;

UAC – User Account Control

• much maligned but still a good protection tool, Mark did a good overview of how it works.
• Windows 95 is the root of all problems, the design principal that system/app configuration only went into HKEY_LOCAL_MACHINE and all per-user configuration should go into HKEY_CURRENT_USER was never adhered to by developers as there was no real requirements to do so, thus Windows has been lumbered with maintaining backward compatibility for generations so as not to upset the user experience.
• Interesting/geeky point for me was that when the screen grey’s for the UAC prompt it’s actually a terminal services based session that presents the UAC dialog and places a grey’d out screenshot of the users desktop as wallpaper.
• When running with UAC enabled, user accounts (even administrators) are run with least privelidge by splitting the authentication token in two, standard and administrative. this breaks some applications that need administrative access, so this is controlled by prompting for credentials (elevation) that run just that process with the required administrative credentials, this requires an application restart if it does not do it at start-up.
• you can manually specify which applications should run with Administrative rights, most built in Vista applications are provided with an compiled in manifest resource record that marks them as requiring UAC elevation.
• Your own or 3rd party apps that do not have this manifest available can be given the same functionality either by marking the file by looking at its compatability settings or using a corresponding .manifest file if you have to distribute the file (if you rename or move the .exe the former method stops applying).
• The built-in Administrator account never sees any UAC prompts regardless of how it’s configured.

WIL – Windows Integrity Levels (formerly Mandatory Integrity Controls)

• WIL was of much more interest to me – it is a core part of Vista protection and works on the basis of assigning integrity levels to files and processes, an integrity level overrides traditional ACL’s and permissions and is on the basis that you cannot change an integrity level unless you have an equal or higher integrity level.
• It was designed to prevent alteration of critical system components (and thus stability/security) even by inattentive administrators or malware that has tricked the user into running it with elevated permissions – it placed several hurdles that administrators must clear to make changes and discouraged casual/badly thought tinkering… which is one of my main bug-bears with Windows, the server OS looks too much like the desktop OS, familiarity breeds contempt in my book.
• It proved controversial/unpopular with the technical community during early betas and was removed at the RC stage; however as Mark put it “they took the sinks away but left the plumbing”, which means its still there and could be exploited by someone building root-kits/malware as it would be very hard to remove or detect without some expert knowledge.
• Mark hinted that he’s been flagging this with Microsoft security for a while and they’ve not made a satisfactory response or mitigation, so in the interest of no security through obscurity he’s giving an overview… positive sign that it made it onto the TechEd agenda I guess – but it’s “in the wild” now and Mark has already written a book covering this during the Vista beta phase.
• Process Explorer can show the Integrity level of a process and Mark Minasi’s tools here can manipulate & view settings

Next up was DS Geek notes from the field, this was a good technical session where Ulf ran through some interesting scenarios and issues he’s encountered working with Active Directory, I’ve seen a lot of these myself as well – but the key points for me were;

• 280 domain admins reduced to 3 with fully delegated model, always a difficult discussion to manage with customers and staff (I have scars to prove it!) his approach was to break each task out and ensure there is only 1 owner – this reduces ambiguity and ensures accountability – with the handy side-effect of demonstrating that 277 of those people didn’t really need to be domain admins to do their day-jobs
• If you accidentally change any properties of a site connection/replication object in AD Sites & Services it changes from being dynamically generated to static without a warning, 2008 now has a dialogue box warning of the change.
• You can change a static connection object back to dynamic by adjusting the “options” attribute for the object in ADSIEDIT from 0x4 (static) to 0x5 (dynamic) rather than deleting and re-creating.
• Virtual Machines are good for DS-Lag sites, where an AD site has one or more domain controllers but where the site replication connector is a day or so behind the rest of the AD, this allows for a simpler restore of deleted objects by marking the object as authorative on the lag site and forcing replication into the production AD – this will bring the object back.
• VM’s lend themselves to this as you can script enabling/disabling the NIC to avoid the situation where there is an accidental (or malicious) deletion followed by a forced replication across all sites.
• LDIFDE import/export can be used to bring back object attributes from a restored AD snapshot (nice functionality that Ulf discusses here).
• Ulf also had an interesting script based solution for a single site (and domain) DC restoration where there is a simple local PC infrastructure like a branch office; where rather than maintaining and copying over the WAN, large system state backups he leveraged LDIFDE in export mode to take a backup of AD and xcopy of files, restoring such a DC after failure can be end-end automated through an unattended OS onto new/replacement hardware and scripts to import and re-ACL the DS objects and file system and re-join machines to the new domain.

Next up was one of two further sessions with Mark Russinovitch, the case of the unexplained – as ever this was informative and he has good coverage of this on his blog which I’d encourage you to check out in hunting down bad/buggy 3rd party driver software which is at fault a large portion of the time, rather than core Windows itself – I have a number of thoughts on why this is the case and will blog those later.

• One useful tidbit that I didn’t know is that Process Monitor can show you what TCP/IP sessions a particular process is using – nice.
• and you can suspend individual threads whilst you investigate what they do or to see if that improves overall performance.

The 2nd of Marks sessions and the final session of TechEd 2008 was on Windows security boundaries; which Microsoft define as an access policy between code and data which describes what if anything is allowed to be shared between the two, anything that could allow access between the two is not a hard security boundary – it is capable of being exploited.

• Mark covered several of the technologies in Windows Vista and 2008 (PatchGuard, UAC, Protected mode IE etc.) and the conclusion is that the only real security boundaries are System & Java Virtual Machines, .NET Code Access Security (CAS) as they are deliberately architected not to allow communication between processes or users and data.
• Didn’t realise this but x64 PatchGuard can blacklist drivers from a list provided by Microsoft.
• As ever, it was an excellent technical session and Mark provided several demos of how the isolation technology works along with some exploits demonstrating why certain types of isolation technology are not hard security boundaries. There is a US version of his presentation which I would encourage you to check out here

All in, it was a good week at TechEd it does feel a bit scaled back from previous years but the technical content of sessions was better at the end of the week – I don’t know if that was deliberate.

One notable omission this year was an equivalent of Andrew Cheeseman’s session on how they built the TechEd infrastructure – this was always a fascinating and entertaining session, I note he has moved on since last year but an equivalent session would have got a good attendance.

As I’ve said many times over, it’s still excellent value for money and I would recommend it to anyone – if you want to know more about my experiences please comment away and I’ll try to answer whatever I can.

You may also want to visit Techhead as he has also been blogging extensively about the sessions this year as has Geert Baeke.

Hope you found these posts useful – feel free to feedback via the comments!

Penultimate day at TechEd, still get the feeling its scaled down this year, but still some good content and some of the best sessions so far today. It was a slightly earlier start and late finish due to the 2pm finish tomorrow, today’s hilights as follows.

Note to Microsoft – early start following the country drinks probably not the wisest move 🙂 1st sessions were pretty quiet this morning 🙂

First session was Migrating and co-existence with Microsoft Online; looking at the steps involved with integrating with Microsoft hosted Exchange services which were shown on Monday’s keynote

Key points for me were;

• This is for Microsoft’s hosted Exchange service only, other providers of managed Exchange like Fasthosts and 1&1 don’t have the same facilities
• Tools support import from a variety of sources, Exchange 200x, Domino, POP3/IMAP, Yahoo mail etc.
• Migration & co-existence tools and documentation are downloadable from the online configuration pages, the tools provided are modified versions of the Exchange Transporter/Migration suite.
• Push-based Dirsync to Microsoft online via dirsync tool which is a packaged up version of the ILM product.
• Co-existence is supported through the use of alias domains, disabled target objects and alternative recipients; basically the same method as the Quest tools use to do a cross-forest migration.
• Don’t have to move all  – can operate a mix of local and hosted mailboxes.
• Because co-existence is basically cross-forest free/busy and delegation do not work across the internal/hosted boundary – Microsoft are hoping to address this; but it’s an inherent issue with this type of co-existence.
• Mailbox ACL’s delegates and rules and RSS feeds are not migrated – user will need to re-create.
• Passwords are not migrated/sync’d so users will need to create a new password via online sign-on wizard.
• Can choose to migrate all or a rule based subset of the mailbox contents
• Clients are not automatically redirected once it’s migrated – need to follow sign-on wizard via Microsoft online service which downloads a new MAPI profile to Outlook

Next up was a journey to the centre of a terminal server; a level 400 technical session on the internals of terminal server logons and processes; there was far too much technical information for me to blog so I’ll provide some links.

• Terminal services has now officially been renamed to Remote Desktop Services see here
• A comprehensive Whitepaper on tuning terminal services has been released here
• Terminal Services in Windows 2008 is much more modular with 3 component services, this separation enables much better separation of session management behind the scenes.
• New TS app analyser has been released, which can examine applications and determine their suitability for use on a terminal server looking for common permissions/file issues.
• One thing to watch with RemoteApp sessions is that a full desktop is rendered in the background, if that user profile or application spawns a window-less UI it can become a stuck zombie process when the user closes the RemoteApp session, Acrobat Reader updater (AcroTray) is a common culprit.
• There is a complicated issue with registry profile time stamps in a TS farm which to be honest I don’t fully understand – but Immidio have some free tools to assist with this, Tritsch is an excellent presenter and certainly knows his material

Next was Anatomy of a hack 2008 by Jesper Johansson, showing how malware is being pimped in the guise of anti-malware software!

key points were;

• It’s all about the money – organised crime running the same sort of bait and switch scams as they always did, but now on a massive, easy to do scale.
• Malware developers are getting good, and well organised with some innovative and well thought out lures.
• Some Malware now alter their behaviour if it detects that it is running inside a VM to avoid security researchers usual MO.
• Fraudulent transactions are going to Eastern Europe and infrastructure is distributed around the globe to handle transactions and Malware distribution
• They are definitely targeting layer 8 issues rather than technical steps to compromise systems through vulnerabilities; preying on the naive, careless or less informed.
• difficult to prevent, education and caution the key

Last session of the day was with Mark Russinovitch (of Sysinternals.com fame) on Windows 2008 R2 Virtualization and native VHD support.

How Mark manages to keep all the encyclopedic amount of internal Windows information inside his normal sized head  I don’t know – but his sessions are always very detailed and thorough.

Key points for me were;

• This was the 1st session I attended that Windows 2008 Hyper V has been referred to as Hyper V 2.0.
• there are comprehensive power management improvements in R2 which are propagated through to Hyper V; allowing suspend “parking” of individual CPU cores and consolidating CPU core workload to the minimum required to provide service – thus reducing overall power requirements.
• Intel and AMD have EPT and NPT technology embedded into new CPUs which will handle shadow page table mapping in hardware delivering significant performance improvements and reducing host OS usage.
• VHD (Virtual Hard Disk format) is a strategic direction for Microsoft, intended to replace all other container formats (CAB, ZIP, WIM etc.).
• VHD is an open, documented file format – open to 3rd party solutions and integrations.
• Windows Backup in Vista and 2008 already write backup data out to a VHD file.
• Improved Windows 7 / Server 2008 R2 boot manager will support boot from VHD, BCEDIT is used to point at a file system mounted VHD file rather than the traditional partition.
• Pagefile and boot loader need to remain on a physical partition.
• This enables some highly flexible multi-boot scenarios and makes P2V, V2P much easier.
• Mark showed his laptop which was booting Windows 7 from a VHD file.
• Boot from VHD also supports differential disks, this enables some very cool scenarios where the root disk is a known good/safe image with all changes being written into a differential VHD – allows for neat roll back to a standard condition (Internet kiosk type scenario) or protection from patching etc.
• Also allows for offline servicing of OS through patching too.
• Allows ISV’s to deliver apps or even whole OS/VM installations ready to use (appliances).
• nesting VHD files inside each other is not recommended and >2 levels is not supported.

A final thought from me on this is that if they were to integrate the SIS (Single Instance Storage) features of the .WIM format into VHD files then that would be a very compelling solution for VDI farms, VM terminal servers, and would make the download/streaming of VM images (via MED-V) very efficient, you could distribute a single VHD with multiple variations of a Vista or XP OS build in a very storage efficient manner.

Ok, so that was day 4 – last day tomorrow!