[python-win32] SSPI memory problems with Kerberos?

[Matt Hamilton]

Hi all, I've been trying to use the win32 SSPI API to do some Kerberos auth 
stuff. After a lot of banging my head against the wall I've now pared the 
problem right down to the very basics and this is what I'm getting:


# sspitest.py
import sspi

data = 'bogus'
sa = sspi.ServerAuth('Kerberos')
err, sec_buffer = sa.authorize(data)


C:\krbtest>c:\Python26\python.exe sspitest.py
Traceback (most recent call last):
  File "sspitest.py", line 5, in <module>
    err, sec_buffer = sa.authorize(data)
  File "c:\Python26\lib\site-packages\win32\lib\sspi.py", line 196, in 
authorize

    self.datarep, self.ctxt, sec_buffer_out)
pywintypes.error: (-2146893056, 'AcceptSecurityContext', 'Not enough 
memory is available to complete this request')

Originally I was passing it a valid Kerberos ticket, but no matter what it 
would still give me that memory error. So I decided to pass in some bogus 
data to at least get a different error... but no dice. I always just get this 
memory error.

Whereas if I use NTLM instead, I get the error I would expect:

# sspitest.py
import sspi

data = 'bogus'
sa = sspi.ServerAuth('NTLM')
err, sec_buffer = sa.authorize(data)
	

C:\krbtest>c:\Python26\python.exe sspitest.py
Traceback (most recent call last):
  File "sspitest.py", line 5, in <module>
    err, sec_buffer = sa.authorize(data)
  File "c:\Python26\lib\site-packages\win32\lib\sspi.py", line 196, in 
authorize

    self.datarep, self.ctxt, sec_buffer_out)
pywintypes.error: (-2146893048, 'AcceptSecurityContext', 'The token 
supplied to the function is invalid')

Any ideas? I've tried searching various windows forums about that 
error message in general as I'm guessing the python lib is just a thin 
wrapper around the win32 call, but can't find anything useful there either.

I'm running this on a Windows 2003 SP2 server using Python 2.6.6 
and pywin32-216.

-Matt