RE: [squid-users] Reverse Proxy, OWA RPCoHTTPS and NTLM authentication passthrough

Amos,

I've never been able to get NTLM pass thru to work with squid, I'm guessing because of the double hop issue. Kerberos, on the other hand, works perfectly once you've set up all the service principle names etc and is also much more secure. If you can get Kerberos working between the client and the OWA server directly, you can slot squid in the middle and the clients won't care.

Joe Tiedeman
Support Analyst
Higher Education Statistics Agency (HESA)
95 Promenade, Cheltenham, Gloucestershire GL50 1HZ
T 01242 211167 F 01242 211122 W www.hesa.ac.uk

-----Original Message-----
From: Amos Jeffries [mailto:squid3_at_treenet.co.nz]
Sent: Thursday 17 July 2008 11:18
To: Abdessamad BARAKAT
Cc: squid-users_at_squid-cache.org
Subject: Re: [squid-users] Reverse Proxy, OWA RPCoHTTPS and NTLM authentication passthrough

Abdessamad BARAKAT wrote:
>
> Hi people,
>
> Nobody for give me a feedback about this feature ( ntlm auth pass
> through) ?

You know as much about this as most here. It don't work.

I'm no expert myself but I suspect the reason goes something like this:
(wild guess)
   NTLM is a sub-band authentication in background channels directly between the server and client. Now client thinks the reverse-proxy IS the server so is happy to authenticate with it. Squid is possibly able to pass the login details back to exchange, which required NTLM with the client. Client goes, hang on a minute I wasn't talking to you, and kills the auth. Squid does not have the client-stored secret information to setup a fake NTLM sequence to exchange on behalf of the username/pass it knows.

As I said, I'm no expert, but it seems to me that is likely what the issue is. If I'm wrong can someone please indicate why such an old and popular item as NTLM re-auth has not been implemented in _any_ version of Squid yet?

Amos

>
> Thanks
>
>
> Le 14 juil. 08 à 12:39, Abdessamad BARAKAT a écrit :
>
>> Hi,
>>
>> I need to reverse proxied a OWA 2007 service and I have some problems
>> with NTLM authentication and the RPC connection. Squid offers a SSL
>> service and connect himself to the OWA with a SSL connection
>>
>> The NTLM authentication was made bu the OWA so I need squid to pass
>> the credentials without modified them.
>>
>> Actually I get only 401 error code but when I switch the
>> authentication to "Basic authentication" on the Outlook anywhere's
>> settings, It's working. I want really to have the NTLM authentication
>> working for don't ask all users to change their settings.
>>
>> The squid is chrooted.
>>
>> I have tried the following versions:
>>
>> - 3.0 STABLE7
>>
>> - 2.7STABLE3
>>
>> - 2.6STABLE21
>>
>> - 2.6STABLE3
>>
>> My setup (sometime I need to add acl all or logfile_daemon beetween
>> versions, that's all) :
>>
>> #### CHROOT
>> chroot /usr/local/squid
>> mime_table /etc/mime.conf
>> icon_directory /share/icons
>> error_directory /share/errors/English unlinkd_program
>> /libexec/unlinkd cache_dir ufs /var/cache 100 16 256 cache_store_log
>> /var/logs/store.log access_log /var/logs/access.log squid
>> pid_filename /var/logs/squid.pid logfile_daemon
>> /libexec/logfile-daemon ####
>>
>> # Define the required extension methods extension_methods RPC_IN_DATA
>> RPC_OUT_DATA
>>
>> # Publish the RPCoHTTP service via SSL https_port 192.168.1.122:8443
>> cert=/etc/apache2/ssl/webmail.corporate.com.p
>> em defaultsite=webmail.corporate.com
>> cache_peer 172.16.18.13 parent 443 0 no-query originserver login=PASS
>> ssl sslfl ags=DONT_VERIFY_PEER name=exchangeServer
>>
>> acl all src 0.0.0.0/0.0.0.0
>> acl EXCH dstdomain .corporate.com
>> cache_peer_access exchangeServer allow EXCH cache_peer_access
>> exchangeServer deny all never_direct allow EXCH # Lock down access to
>> just the Exchange Server!
>> http_access allow EXCH
>> http_access deny all
>> miss_access allow EXCH
>> miss_access deny all
>>
>> #no local caching
>> #maximum_object_size 0 KB
>> #minimum_object_size 0 KB
>> #no_cache deny all
>>
>> #access_log /usr/local/squid/var/logs/access.log squid
>>
>>
>> Thanks a lot for any tips or informations .
>>
>>
>> !DSPAM:487b2e138671238159409!
>>
>

--
Please use Squid 2.7.STABLE3 or 3.0.STABLE7
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