Build as separate image with ipv6 support

Author: jviide

Dockerfile

@@ -5,7 +5,8 @@ COPY . .
 RUN go build -o /tracetrout -ldflags='-s -w'
 
 FROM alpine:3.7
-RUN apk add --no-cache iptables ip6tables libnetfilter_queue
+ARG IPV6_SUPPORT
+RUN apk add --no-cache iptables libnetfilter_queue ${IPV6_SUPPORT:+ip6tables}
 WORKDIR /tracetrout
 COPY entrypoint.sh .
 COPY --from=builder /tracetrout .

circle.yml

@@ -10,14 +10,18 @@ jobs:
       - setup_remote_docker:
           version: 17.06.0-ce
       - run: docker build -t ${DOCKER_HUB_IMAGE} .
+      - run: docker build --build-arg IPV6_SUPPORT=1 -t ${DOCKER_HUB_IMAGE}:ipv6 .
       - deploy:
           name: Deploy the image to Docker Hub
           command: |
             if echo -n "${CIRCLE_TAG}" | grep -Eq ^v[0-9]+\.[0-9]+\.[0-9]+$; then
               docker tag ${DOCKER_HUB_IMAGE} ${DOCKER_HUB_IMAGE}:${CIRCLE_TAG}
+              docker tag ${DOCKER_HUB_IMAGE}:ipv6 ${DOCKER_HUB_IMAGE}:${CIRCLE_TAG}-ipv6
               docker login -u ${DOCKER_HUB_USER} -p ${DOCKER_HUB_PASS}
               docker push ${DOCKER_HUB_IMAGE}:${CIRCLE_TAG}
               docker push ${DOCKER_HUB_IMAGE}
+              docker push ${DOCKER_HUB_IMAGE}:${CIRCLE_TAG}-ipv6
+              docker push ${DOCKER_HUB_IMAGE}:ipv6
             fi
 
 deployment:

entrypoint.sh

@@ -1,6 +1,8 @@
 set -e
 
 for CMD in iptables ip6tables; do
+  command -v ${CMD} > /dev/null 2>&1 || continue
+
   "${CMD}" -A INPUT -t mangle -j CONNMARK --restore-mark
   "${CMD}" -A INPUT -t mangle -m mark ! --mark 0 -j ACCEPT
   "${CMD}" -A INPUT -t mangle -p tcp --dport "${PORT}" -j MARK --set-mark 0x10000