github/kubernetes
1
0
Fork 0
mirror of https://github.com/k3s-io/kubernetes.git synced 2025-08-06 10:43:56 +00:00
Code Issues Projects Releases Wiki Activity

Add mode-detecting iptables wrappers to the debian-iptables image

Browse Source
This commit is contained in:
Dan Winship 2019-09-21 10:18:27 -04:00
parent ee681f7bd3
commit fed582333f
2 changed files with 53 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
build/debian-iptables/Dockerfile
View File

@ -14,10 +14,28 @@
FROM BASEIMAGE FROM BASEIMAGE
# Install latest iptables package from buster-backports
RUN echo deb http://deb.debian.org/debian buster-backports main >> /etc/apt/sources.list; \
apt-get update; \
apt-get -t buster-backports -y --no-install-recommends install iptables
# Install other dependencies and then clean up apt caches
RUN clean-install \ RUN clean-install \
conntrack \ conntrack \
ebtables \ ebtables \
ipset \ ipset \
iptables \
kmod \ kmod \
netbase netbase
# Install iptables wrapper scripts to detect the correct iptables mode
# the first time any of them is run
COPY iptables-wrapper /usr/sbin/iptables-wrapper
RUN update-alternatives \
--install /usr/sbin/iptables iptables /usr/sbin/iptables-wrapper 100 \
--slave /usr/sbin/iptables-restore iptables-restore /usr/sbin/iptables-wrapper \
--slave /usr/sbin/iptables-save iptables-save /usr/sbin/iptables-wrapper
RUN update-alternatives \
--install /usr/sbin/ip6tables ip6tables /usr/sbin/iptables-wrapper 100 \
--slave /usr/sbin/ip6tables-restore ip6tables-restore /usr/sbin/iptables-wrapper \
--slave /usr/sbin/ip6tables-save ip6tables-save /usr/sbin/iptables-wrapper

34
build/debian-iptables/iptables-wrapper Executable file
View File

@ -0,0 +1,34 @@
#!/bin/sh
# Copyright 2019 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
set -e
# Detect whether the base system is using iptables-legacy or
# iptables-nft. This assumes that some non-containerized process (eg
# kubelet) has already created some iptables rules.
num_legacy_lines=$( (iptables-legacy-save || true; ip6tables-legacy-save || true) 2>/dev/null | grep '^-' | wc -l)
num_nft_lines=$( (iptables-nft-save || true; ip6tables-nft-save || true) 2>/dev/null | grep '^-' | wc -l)
if [ "${num_legacy_lines}" -ge "${num_nft_lines}" ]; then
mode=legacy
else
mode=nft
fi
update-alternatives --set iptables "/usr/sbin/iptables-${mode}" > /dev/null
update-alternatives --set ip6tables "/usr/sbin/ip6tables-${mode}" > /dev/null
# Now re-exec the original command with the newly-selected alternative
exec "$0" "$@"