Since #116 implemented fragile comparisons of iptables rules to avoid
calling the iptables binary excessively during every reconciliation, the
iptables rules for IPIP encapsulation must be updated to match the
expected output. One complication is that rather than returning the
protocol number in the rule, iptables resolves the protocol number to a
name by looking up the number in the netd protocols database. This name
can vary depending on the host's environment. This commit adds two
solutions for resolving the protocol name:
1. a fixed mapping to the string `ipencap`, which should always work
for Kilo whenever it runs in the Alpine Linux container; and
2. a runtime lookup using the netd database, which only works if Kilo is
compiled with CGO and is meant to be used only if Kilo is not running in
the normal container environment.
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>
This commit enables simultaneously managing IPv4 and IPv6 iptables
rules. This makes it possible to have peers with IPv6 allowed IPs in an
otherwise IPv4 stack and vice versa.
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>
This commit better organizes the location of iptables rules. This is
made possible by exposing two new funcs, `NewRule` and `NewChain`.
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>
This commit adds basic support to run in compatibility mode with
Flannel. This allows clusters running Flannel as their principal
networking solution to leverage some advances Kilo features. In certain
Flannel setups, the clusters can even leverage muti-cloud. For this, the
cluster needs to either run in a full mesh, or Flannel needs to use the
API server's external IP address.
