ipgrep

#!/bin/bash
# search input for ipv4 and ipv6 addresses

grep -o -E '(((([0-9a-fA-F]){1,4}:){7,7}[0-9a-fA-F]{1,4})|(([0-9a-fA-F]){1,4}:){1,7}:|(([0-9a-fA-F]){1,4}:){1,6}:[0-9a-fA-F]{1,4}|(([0-9a-fA-F]){1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|(([0-9a-fA-F]){1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|(([0-9a-fA-F]){1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|(([0-9a-fA-F]){1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))|([0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3})'