Add kill-connections

kill-connections

@@ -0,0 +1,47 @@
+#!/bin/bash
+if [[ $# -ne 1 || "$1" == '-h' || "$1" == '--help' ]]
+then
+	echo "Usage: kill-connections PID" >&2
+	exit 1
+fi
+
+if ! command -v tcp-closer &>/dev/null
+then
+	echo "Error: could not find tcp-closer" >&2
+	exit 1
+fi
+
+declare -i pid="$1"
+if ! kill -0 ${pid} &>/dev/null
+then
+	echo "Error: no process ${pid}" >&2
+	exit 1
+fi
+
+kill -STOP ${pid}
+
+echo "Open connections:" >&2
+lsof -a -p ${pid} -i TCP -n >&2
+echo >&2
+
+v4sports="$(lsof -a -p ${pid} -i4 -i TCP -n -F nP0 | grep -Pao '\x00n\d{1,3}(\.\d{1,3}){3}:\K\d+' | tr '\n' ' ' | sed 's/ $//; s/ / -s /g')"
+if [[ "${v4sports}" ]]
+then
+	echo "Killing IPv4 connections" >&2
+	#TODO tcp-closer only supports up to 128 sports at once; split it up if there are more.
+	#TODO This may also kill connections we want to keep. tcp-closer does not allow specifying the full (src, sport, dst, dport) tuple...
+	tcp-closer -4 -s ${v4sports}
+	echo >&2
+fi
+v6sports="$(lsof -a -p ${pid} -i6 -i TCP -n -F nP0 | grep -Pao '\x00n\[[^\]]+\]:\K\d+' | tr '\n' ' ' | sed 's/,$//; s/ / -s /g')"
+if [[ "${v6sports}" ]]
+then
+	echo "Killing IPv6 connections" >&2
+	tcp-closer -6 -s ${v6sports}
+	echo >&2
+fi
+
+echo "Open connections:" >&2
+lsof -a -p ${pid} -i TCP -n >&2
+
+kill -CONT ${pid}