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An authentication handler for using Kerberos with Python Requests.
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Latest commit ee5c291 Apr 20, 2016 @Lukasa Lukasa Merge pull request #69 from nitzmahone/winrm_mutual_auth_fix
Fix for mutual auth on winrm


requests Kerberos/GSSAPI authentication library

Requests is an HTTP library, written in Python, for human beings. This library adds optional Kerberos/GSSAPI authentication support and supports mutual authentication. Basic GET usage:

>>> import requests
>>> from requests_kerberos import HTTPKerberosAuth
>>> r = requests.get("", auth=HTTPKerberosAuth())

The entire requests.api should be supported.

Authentication Failures

Client authentication failures will be communicated to the caller by returning the 401 response.

Mutual Authentication

By default, HTTPKerberosAuth will require mutual authentication from the server, and if a server emits a non-error response which cannot be authenticated, a requests_kerberos.errors.MutualAuthenticationError will be raised. If a server emits an error which cannot be authenticated, it will be returned to the user but with its contents and headers stripped.


If you'd prefer to not require mutual authentication, you can set your preference when constructing your HTTPKerberosAuth object:

>>> import requests
>>> from requests_kerberos import HTTPKerberosAuth, OPTIONAL
>>> kerberos_auth = HTTPKerberosAuth(mutual_authentication=OPTIONAL)
>>> r = requests.get("", auth=kerberos_auth)

This will cause requests_kerberos to attempt mutual authentication if the server advertises that it supports it, and cause a failure if authentication fails, but not if the server does not support it at all.


While we don't recommend it, if you'd prefer to never attempt mutual authentication, you can do that as well:

>>> import requests
>>> from requests_kerberos import HTTPKerberosAuth, DISABLED
>>> kerberos_auth = HTTPKerberosAuth(mutual_authentication=DISABLED)
>>> r = requests.get("", auth=kerberos_auth)

Preemptive Authentication

HTTPKerberosAuth can be forced to preemptively initiate the Kerberos GSS exchange and present a Kerberos ticket on the initial request (and all subsequent). By default, authentication only occurs after a 401 Unauthorized response containing a Kerberos or Negotiate challenge is received from the origin server. This can cause mutual authentication failures for hosts that use a persistent connection (eg, Windows/WinRM), as no Kerberos challenges are sent after the initial auth handshake. This behavior can be altered by setting force_preemptive=True:

>>> import requests
>>> from requests_kerberos import HTTPKerberosAuth, REQUIRED
>>> kerberos_auth = HTTPKerberosAuth(mutual_authentication=REQUIRED, force_preemptive=True)
>>> r = requests.get("", auth=kerberos_auth)


This library makes extensive use of Python's logging facilities.

Log messages are logged to the requests_kerberos and requests_kerberos.kerberos_ named loggers.

If you are having difficulty we suggest you configure logging. Issues with the underlying kerberos libraries will be made apparent. Additionally, copious debug information is made available which may assist in troubleshooting if you increase your log level all the way up to debug.

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