Incompatibility between krb's AES256-CTS-HMAC-SHA1-96 and Microsoft Windows Domain

[Idan Freiberg]

On MS Active Directory Domain Controllers there’s a tool called ktpass.exe
It will generate the correct key tabs for you.

בתאריך יום ו׳, 10 בנוב׳ 2017 ב-12:57 מאת Simo Sorce <simo at redhat.com>:

> You may want to look into a utility called mskutil.
>
> HTH,
> Simo.
>
> On Fri, 2017-11-10 at 08:08 +0300, Ido Shlomo wrote:
> > Thank you. I understand the options, but I am not familiar with tools
> > that
> > may do that automatically. (currently this entire process is
> > automated
> > using shell scripts).
> >
> > On Nov 10, 2017 01:47, "Simo Sorce" <simo at redhat.com> wrote:
> >
> > > Ido,
> > > the problem is that you do not get the key out of AD but you use
> > > kerberos utils to generate it. As mentioned before when you do that
> > > the
> > > "wrong" salt is used, so your keys cannot work.
> > >
> > > It works for "users" because it just so happen that both the AD KDC
> > > and
> > > your utilities use the same logic to derive keys for UPNs. But AD
> > > uses
> > > a different logic for SPNs.
> > >
> > > You need to either modify your utilities to deal with the salt
> > > "properly" according to how the KDC generates hashes from a
> > > password,
> > > or you need to use utilities that let the KDC generate the keys and
> > > give you back a keytab,
> > > That's it, there is no other way around.
> > >
> > > Simo.
> > >
> > > On Thu, 2017-11-09 at 23:03 +0300, Ido Shlomo wrote:
> > > > No. I am registering an SPN for a single account.
> > > > The operation has 2 phases:
> > > > Add an entry to the local keytab using ktuil.
> > > > Add an entry to the User object in the Active Directory using
> > > > openldap.
> > > >
> > > >
> > > > On Nov 9, 2017 20:10, "Isaac Boukris" <iboukris at gmail.com> wrote:
> > > >
> > > > >
> > > > >
> > > > > On Thu, Nov 9, 2017 at 5:00 PM, Ido Shlomo <shloim at gmail.com>
> > > > > wrote:
> > > > > > The thing is that kinit works well for the user (not
> > > > > > computer)
> > > > > > The problem is that I register an SPN on the DC for that user
> > > > > > (again, not
> > > > > > computer) using ldap, and then I resgister the same SPN
> > > > > > (MSSQL/mymachine.domain.com:1433 at DOMAIN.COM). The problem
> > > > > > occurs
> > > > > > when an
> > > > > > incoming connection gives me a token that I cannot accept.
> > > > > > The
> > > > > > error is
> > > > >
> > > > > that
> > > > > > I cannot decrypt it.
> > > > >
> > > > > Wait, are you registering the same SPN twice to two different
> > > > > accounts?
> > > > > You aren't supposed to do that I think, as the KDC might
> > > > > encrypt
> > > > > the
> > > > > ticket with the key of the other principal.
> > > > >
> > >
> > > --
> > > Simo Sorce
> > > Sr. Principal Software Engineer
> > > Red Hat, Inc
> > >
> > >
>
> --
> Simo Sorce
> Sr. Principal Software Engineer
> Red Hat, Inc
>
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>
-- 
Idan Freiberg

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