daemon/libnetwork/support: refresh Dockerfile and script

- update the Dockerfile to switch to the cli-variant (as it doesn't
  require a docker daemon), and update to the latest v29 image
- update the script to not use the deprecated libnetwork repository

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/libnetwork/support/Dockerfile

@@ -1,8 +1,7 @@
-FROM docker:18-dind
+# syntax=docker/dockerfile:1
+
+FROM docker:29-cli
 
-RUN set -ex \
-    && echo "http://nl.alpinelinux.org/alpine/edge/main" >> /etc/apk/repositories \
-    && echo "http://nl.alpinelinux.org/alpine/edge/testing" >> /etc/apk/repositories
 RUN apk add --no-cache \
     util-linux \
     bridge-utils \
@@ -17,4 +16,4 @@ RUN apk add --no-cache \
 WORKDIR /bin
 COPY *.sh /bin/
 
-CMD /bin/run.sh
+CMD ["/bin/run.sh"]

daemon/libnetwork/support/README

@@ -1 +1 @@
-Usage: docker run -v /var/run:/var/run  --network host --privileged dockereng/network-diagnostic:support.sh
+Usage: docker run --rm -v /var/run:/var/run --network host --privileged dockereng/network-diagnostic:support.sh

daemon/libnetwork/support/run.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 # try to fetch the latest version from github
-wget -O support.sh.new https://raw.githubusercontent.com/docker/libnetwork/master/support/support.sh
+wget -O support.sh.new https://raw.githubusercontent.com/moby/moby/refs/heads/master/daemon/libnetwork/support/support.sh
 
 if [ "$?" -eq "0" ]; then
 	mv support.sh.new support.sh