Add delegation for SPNEGO back to JMeter

[FSchumacher]

Description

Newer httpclient versions (at least in the 4.x branch) have dropped the support for delegation of kerberos tickets over SPNEGO. This patch brings back the support to delegation back to JMeter.

Motivation and Context

Older versions of JMeter always tried to get forwardable tickets when using SPNEGO. As I need this functionality for a service, I would like to have the forwarding back. As the default forwarding could be seen critical from a security standpoint, the patch disables it by default. It can be enabled by a system property.

How Has This Been Tested?

Tested it on a service that depends on delegation of tickets.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue) (At least I see this as a regression)

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.

[pmouawad]

Thanks for PR.
Just wondering, why do we use httpcomponents package ?

• org.apache.http.impl.auth.DelegatingKerberosScheme
• org.apache.http.impl.auth.DelegatingSPNegoScheme

Thanks

[FSchumacher]

I thought I hat to overwrite the method createGSSContext, which is only possible on a subclass in the same package. I changed it now explicitly to call another method and placed the classes in JMeter's package namespace. Will check on Monday, if it is still working.

[pmouawad]

Thanks Felix

[pmouawad]

Hi Felix,
Did you have time to check the changes are working ?
If yes, +1 for committing it.