[Bug 1643708] Re: Add SPNEGO special case for NTLMSSP+MechListMIC

[Joshua R. Poulson]

[Test Case]

create a file with some credentials:

$ echo F23:guest:guest > ~/ntlmcreds.txt
$ export NTLM_USER_FILE=~/ntlmcreds.txt
$ python
import gssapi

spnego = gssapi.raw.oids.OID.from_int_seq('1.3.6.1.5.5.2')
c = gssapi.creds.Credentials(mechs=[spnego], usage='initiate')
tname = gssapi.raw.names.import_name("F23/server", name_type=gssapi.raw.types.NameType.hostbased_service)
ac = gssapi.creds.Credentials(mechs=[spnego], usage='accept')

seci = gssapi.SecurityContext(creds=c, name=tname, mech=spnego, usage='initiate')
seca = gssapi.SecurityContext(creds=ac, usage='accept')
it = seci.step(token=None)
ot = seca.step(token=it)
it = seci.step(token=ot)
ot = seca.step(token=it)
it = seci.step(token=ot)

e = seci.wrap("Secrets", True)
o = seca.unwrap(e.message)

o.message
'Secrets'

So far I checked with GDB that the seq numbers were reset after the
MEchListMIC operation happened and started again from 0.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to krb5 in Ubuntu.
https://bugs.launchpad.net/bugs/1643708

Title:
  Add SPNEGO special case for NTLMSSP+MechListMIC

Status in krb5 package in Ubuntu:
  Fix Released
Status in krb5 source package in Trusty:
  Incomplete
Status in krb5 source package in Xenial:
  Incomplete
Status in krb5 source package in Yakkety:
  Incomplete

Bug description:
  MS-SPNG section 3.3.5.1 documents an odd behavior the SPNEGO layer
  needs to implement specifically for the NTLMSSP mechanism.  This is
  required for compatibility with Windows services.

  Upstream commit:
  https://github.com/krb5/krb5/commit/cb96ca52a3354e5a0ea52e12495ff375de54f9b7

  We've run into this issue with Linux to Windows negotiation with
  encrypted http using GSSAPI.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/krb5/+bug/1643708/+subscriptions