This gets us closer to passing the iptables tests and opens up iptables
so it can be worked on by multiple people.
A few restrictions are enforced for security (i.e. we don't want to let
users write a bunch of iptables rules and then just not enforce them):
- Only the filter table is writable.
- Only ACCEPT rules with no matching criteria can be added.
It would be preferrable to test iptables via syscall tests, but there are some
problems with that approach:
* We're limited to loopback-only, as syscall tests involve only a single
container. Other link interfaces (e.g. fdbased) should be tested.
* We'd have to shell out to call iptables anyways, as the iptables syscall
interface itself is too large and complex to work with alone.
* Running the Linux/native version of the syscall test will require root, which
is a pain to configure, is inherently unsafe, and could leave host iptables
misconfigured.
Using the go_test target allows there to be no new test runner.
PiperOrigin-RevId: 285274275