How to get Kerberos token for proxy authentication

[Ken Hornstein]

>Hi, I have a requirement to authenticate my application
>(Golang)  against a proxy server which requires Kerberos
>authentication.  I have achieved this on Windows using
>github/alexbrainman/sspi Golang package.From that package I
>basically call  negotiate.AcquireCurrentUserCredentials() and
>negotiate.NewClientContext() to get the client token which gets passed
>to the proxy server in Proxy-Authorization header.  I want to achieve
>the same on macOS and looking for suitable libraries.  Can I use MIT
>Kerberos library for this purpose ?what are the APIs equivalent to get
>client token without prompting the user for password ? The user would
>have acquired Kerberos ticket on sign-in as a domain user.

I believe you would want to use the GSSAPI for this.  If your header
looks like:

Proxy-Authorization: Negotiate <base64 encoded data>

Then definitely you want to use that.  You could use libcurl as example
code if you wanted to see what this would look like.

--Ken