getpeerhost.sh

#!/bin/bash

if [[ $# -ne 2 ]]; then
    echo "Need parameters: PROCESS_NAME showpid|showport|showhost|showconn"
    exit 1
fi

PROCESS_NAME=$1
ACTION=$2

PIDS=$(pgrep -f $PROCESS_NAME | tr -s '[:space:]' ',')
PIDS=${PIDS%?}

if [[ $ACTION == "showpid" ]]; then
    ps -p $PIDS -o cmd= | grep -v '^/bin/bash' | awk '{print $1}' | sort -u
    exit
fi

PORTS=$(lsof -anP -iTCP -sTCP:LISTEN -p $PIDS | grep -E 'TCP .+:[0-9]+ ' -o | awk -F':' '{print $2}' | tr -s '[:space:]' '|')
PORTS=${PORTS%?}

if [[ $ACTION == "showport" ]]; then
    lsof -anP -iTCP -sTCP:LISTEN -p $PIDS | grep -E 'TCP .+:[0-9]+ ' -o | awk -F':' '{print $2}' | sort -nu
    exit
fi

if [[ $ACTION == "showhost" ]]; then
    lsof -anP -iTCP -sTCP:ESTABLISHED -p $PIDS | grep -E "TCP .+:($PORTS)->.+:[0-9]+ " -o | awk -F'->' '{print $2}' | awk -F':' '{print $1}' | sort -u
    exit
fi

if [[ $ACTION == "showconn" ]]; then
    lsof -anP -iTCP -sTCP:ESTABLISHED -p $PIDS | grep -E "TCP .+:($PORTS)->.+:[0-9]+ " -o
    exit
fi