[squid-users] Re: Re: Re: Re: SSO with Active Directory-Squid Clients

From: Markus Moeller <huaraz_at_moeller.plus.com>
Date: Fri, 9 Apr 2010 08:16:51 +0100

Hi Bilal,

  What you do is a possible option, but has in my view 3 problems.

  1) In a large enterprise you really do not want additional user accounts
without password expiry as you have to have a process in place to recertify
them regularly
  2) It means when the administrator leaves you have to change all passwords
of keytab accounts as it might be otherwise a backdoor

  3) Do not use DES it is deprecated in Windows 7 /2008 and will be in the
next MIT/Heimdal releases

The msktutil tool creates in comparision a Computer account and it does it
from your Unix machine, and therefore does not have the overhead of
transfering keytabs around. And as I described in my other post you can
control access to OUs so that Unix administrators can use msktutil.

Regards
Markus

"GIGO ." <gigoz_at_msn.com> wrote in message
news:SNT134-w588E173F39449195CA6126B9150_at_phx.gbl...

Hi Markus/Nick,

I have chosen the following method of creating the keytab can you give me
your advice/expereince regarding it.

1. I have created a user account for SPN in Active directory with password
never expires and preauthentication not required checked.

squidLhr-proxy
Pwd: XXXXX

C:\Program Files\Support Tools>
setspn -A HTTP/squidLhr-proxy.v.mcb.com.pk squidLhr-proxy

Creating keytab:
ktpass -out c:\squidLhr-proxy.keytab -princ
HTTP/squidLhr-proxy.v.com.pk_at_MYREALM.V.COM.PK -mapUser
V\squidLhr-proxy -mapOp set -pass * -crypto DES-CBC-MD5 -pType
KRB_NT_PRINCIPAL

regards,

Bilal

----------------------------------------
> To: squid-users_at_squid-cache.org
> From: huaraz_at_moeller.plus.com
> Date: Thu, 8 Apr 2010 20:08:10 +0100
> Subject: [squid-users] Re: Re: Re: SSO with Active Directory-Squid Clients
>
> Hi Nick,
>
> Did you use samba to create the keytab. I have seen that if you use samba
> for more then squid (e.g. cifs, winbind, etc) it will update regularly the
> AD entry and key for the host/fqdn principal which is the same as for
> HTTP/fqdn. I usually use msktutil and create a second AD entry called
> -HTTP to be independent of samba which usually uses
> .
>
> Regards
> Markus
>
> "Nick Cairncross" wrote in message
> news:C7E35DA9.1EB06%Nick.Cairncross_at_condenast.co.uk...
> Bilal,
>
> I'm working on much the same thing, with added Apple Mac just to
> complicate
> things. My aim is to create an SSO environment for all my Windows, OSX and
> nix machines. I want to use Kerberos as my primary authentication as IE7
> and
> FF onwards are moving that way..but for my situation some browsers or
> applications do not support this and I must also use NTLM. However, Opera
> on my Macs seems to not like either and prefers Basic.. It's been a
> struggle
> to get each element to work but not impossible.
>
> I have found that all Negotiate/Kerberos supporting browsers have worked
> extremely well with the helper developed by Markus. Many of the
> authentication breaking elements have disappeared when compared to my Blue
> Coat and ISA experiences. Those machines joined to the domain using
> browsers
> that support Neg/Kerb work seamlessly with Kerberos - FF and IE - and pass
> through credentials. Mac Safari relies on NTLM and prompts as such. Mac
> Opera prompts for Basic. Therefore if you're just Windows I would answer
> fairly confidently that your question 1 answer is Yes.
>
> Users not on the domain would be prompted for credentials. I haven't
> tested
> this and depending on which helper you are using (Samba or Squids) and
> whether you're joined to the domain I believe Negotiate should fall back
> to
> NTLM and work providing you supply a valid domain user/pass! So the answer
> to 2 would be 'depends..' :)
>
> As for the issue of not being to able to use Squid at all and taking into
> account what I said earlier, then yes there could be a scenario where
> Squid
> will not work for your users. However, it is less of a problem in just
> Windows. It's all about testing your various Windows configurations, apps
> and browsers until you are sure you have covered the conceivable setups of
> all your users.
> Finally, I have been struggling against an issue where my KVNO Keytab
> increments in AD and gets out of sync with the exported version making
> Squid
> un-useable until it's regenerated. Have you experienced this? Happy to
> discuss any of this off list or on.
>
> Cheers,
> Nick
>
>
>
> On 08/04/2010 04:06, "GIGO ." wrote:
>
>
>
> If i select negotiate/Kerberos as authentication protocol for my Squid on
> Linux and configure no FallBack Authentication.what would be the
> consequence
> ?
>
>
>
> 1. Isnt it that all of my users who have logged into Active Directory and
> where browser is supported will be able to use squid?
>
>
>
> 2. Only those users who will try to use squid from a workgroup giving
> their
> domain passoword (domainname/userid) will fail as there will be no
> fallback
> aviablable.
>
>
>
> 3. Is there any other scenario in which these users will not be able to
> use
> squid?
>
>
>
> I would be really thankful if you guide me further as i am failing to
> understand why a fallback authentication is necessary if it is. What could
> be the scenario when windows clients have no valid TGT even if they are
> login to the domain? I hope you can understand me and help me to clear my
> self.
>
>
> regards,
>
> Bilal Aslam
>
>
>
>
>
>
>
>
>
> ----------------------------------------
>> To: squid-users_at_squid-cache.org
>> From: huaraz_at_moeller.plus.com
>> Date: Wed, 7 Apr 2010 20:17:20 +0100
>> Subject: Re: [squid-users] Re: Re: SSO with Active Directory-Squid
>> Clients
>>
>> Sorry I knew that but forgot to mention that I was talking about the Unix
>> version.
>>
>> Thank you
>> Markus
>>
>> "Guido Serassio" wrote in message
>> news:58FD293CE494AF419A59EF7E597FA4E64002FA_at_hermes.acmeconsulting.loc...
>> Hi Markus,
>>
>>> If you have a Windows client and the proxy send WWW-Proxy-Authorize:
>>> Negotiate the Windows client will try first to get a Kerberos ticket
>> and
>>> if that succeeds sends a Negotiate response with a Kerberos token to
>> the
>>> proxy.
>>> If the Windows client fails to get a Kerberos ticket the client will
>> send
>>> a Negotiate response with a NTLM token to the proxy. Unfortunately
>> there> is yet no squid helper which can handle both a
>> Negotiate/Kerberos response
>>> and a Negotiate/NTLM response (although maybe the samba ntlm helper
>> can).> So there is a fallback when you use Negotiate, but it has some
>> caveats.
>>
>> This is not true when Squid is running on Windows: the Windows native
>> Negotiate Helper can handle both Negotiate/Kerberos and Negotiate/NTLM
>> responses.
>>
>> Regards
>>
>>
>> Guido Serassio
>> Acme Consulting S.r.l.
>> Microsoft Gold Certified Partner
>> VMware Professional Partner
>> Via Lucia Savarino, 1 10098 - Rivoli (TO) - ITALY
>> Tel. : +39.011.9530135 Fax. : +39.011.9781115
>> Email: guido.serassio_at_acmeconsulting.it
>> WWW: http://www.acmeconsulting.it
>>
>>
> _________________________________________________________________
> Hotmail: Trusted email with powerful SPAM protection.
> https://signup.live.com/signup.aspx?id=60969
>
>
> ** Please consider the environment before printing this e-mail **
>
> The information contained in this e-mail is of a confidential nature and
> is
> intended only for the addressee. If you are not the intended addressee,
> any
> disclosure, copying or distribution by you is prohibited and may be
> unlawful. Disclosure to any party other than the addressee, whether
> inadvertent or otherwise, is not intended to waive privilege or
> confidentiality. Internet communications are not secure and therefore
> Conde
> Nast does not accept legal responsibility for the contents of this
> message.
> Any views or opinions expressed are those of the author.
>
> Company Registration details:
> The Conde Nast Publications Ltd
> Vogue House
> Hanover Square
> London W1S 1JU
>
> Registered in London No. 226900
>
>
_________________________________________________________________
Hotmail: Trusted email with Microsoft’s powerful SPAM protection.
https://signup.live.com/signup.aspx?id=60969
Received on Fri Apr 09 2010 - 07:17:13 MDT

This archive was generated by hypermail 2.2.0 : Fri Apr 09 2010 - 12:00:03 MDT