Launchpad Entry: austin-nwfilter or foo
Created: 2010-09-06
Contributors: Soren Hansen
Summary
Use libvirt's built-in filtering mechanisms to contain instances.
Release Note
Nova ensures that guests cannot spoof their MAC nor their IP by making use of libvirt's built-in network filtering mechanism, nwfilter.
Rationale
Containment is essential in the cloud. Users should not be able to snoop or spoof each other's network traffic. Libvirt provides primitives to handle this, so we should use them.
Putting the filtering directly on the host (rather than a central(-ish) firewall) avoids a network bottleneck.
User stories
Eve wants to listen in on Alice's network traffic.
- She tries to simply change her IP to one of Alice's. No traffic entering or leaving the instance with Alice's IP gets through.
- She tries to change her MAC and IP to one of Alice's (thinking that it's all about the MAC and IP having to match up). No traffic entering or leaving the instance at all gets through, because the infrastructure rejecets the MAC from this guest.
- She tries to just send ARP packets, claiming that Alice's IP belongs to Eve's MAC. The infrastructure rejects the ARP packets with the false MAC, so this also fails.
Assumptions
Design
You can have subsections that better describe specific parts of the issue.
Implementation
This section should describe a plan of action (the "how") to implement the changes discussed. Could include subsections like:
UI Changes
Should cover changes required to the UI, or specific UI that is required to implement this
Code Changes
Code changes should include an overview of what needs to change, and in some cases even the specific details.
Migration
Include:
- data migration, if any
- redirects from old URLs to new ones, if any
- how users will be pointed to the new way of doing things, if necessary.
Test/Demo Plan
This need not be added or completed until the specification is nearing beta.
Unresolved issues
This should highlight any issues that should be addressed in further specifications, and not problems with the specification itself; since any specification with problems cannot be approved.
BoF agenda and discussion
Use this section to take notes during the BoF; if you keep it in the approved spec, use it for summarising what was discussed and note any options that were rejected.