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Showing posts from November, 2017

Provisioning Limited Access via Squid Proxy to Docker Containers

You have a Docker environment in your network; you limit outgoing traffic from your servers using a whitelisted proxy configuration (Squid) which can then be used for auditing. You wish to allow some containers access to some sites; perhaps even allow some containers access to any site.

How then, can you grant access based on the container? You need to add an extra level of authentication.

You could set up user-credentials for each container that needs access, but that is an administrative burden, and further a lot of software doesn't work well with a proxy that needs user authentication, which is a support concern.

Or we could use ident lookups to determine the 'user', which can then be used to evaluate ACL conditions. To do that, we would need to set up some specialised 'identd' type service on our docker host(s) that was able to return the container name associated with a given source-dest TCP port pair.

This turns out to be entirely feasible, and has the added …