Non sono riuscito a far funzionare la risposta di @Factor Mystic con le espressioni regolari POSIX, quindi ne ho scritta una che funziona con le espressioni regolari POSIX e le espressioni regolari PERL.
Dovrebbe corrispondere:
Espressione regolare IPv6:
(([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])|([0-9a-fA-F]{1,4}:){1,4}:((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]))
Per facilità di lettura, la seguente è l'espressione regolare sopra divisa nei punti OR principali in linee separate:
# IPv6 RegEx
(
([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}| # 1:2:3:4:5:6:7:8
([0-9a-fA-F]{1,4}:){1,7}:| # 1:: 1:2:3:4:5:6:7::
([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}| # 1::8 1:2:3:4:5:6::8 1:2:3:4:5:6::8
([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}| # 1::7:8 1:2:3:4:5::7:8 1:2:3:4:5::8
([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}| # 1::6:7:8 1:2:3:4::6:7:8 1:2:3:4::8
([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}| # 1::5:6:7:8 1:2:3::5:6:7:8 1:2:3::8
([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}| # 1::4:5:6:7:8 1:2::4:5:6:7:8 1:2::8
[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})| # 1::3:4:5:6:7:8 1::3:4:5:6:7:8 1::8
:((:[0-9a-fA-F]{1,4}){1,7}|:)| # ::2:3:4:5:6:7:8 ::2:3:4:5:6:7:8 ::8 ::
fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}| # fe80::7:8%eth0 fe80::7:8%1 (link-local IPv6 addresses with zone index)
::(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])| # ::255.255.255.255 ::ffff:255.255.255.255 ::ffff:0:255.255.255.255 (IPv4-mapped IPv6 addresses and IPv4-translated addresses)
([0-9a-fA-F]{1,4}:){1,4}:
((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]) # 2001:db8:3:4::192.0.2.33 64:ff9b::192.0.2.33 (IPv4-Embedded IPv6 Address)
)
# IPv4 RegEx
((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])
Per rendere quanto sopra più facile da capire, il seguente codice "pseudo" replica quanto sopra:
IPV4SEG = (25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])
IPV4ADDR = (IPV4SEG\.){3,3}IPV4SEG
IPV6SEG = [0-9a-fA-F]{1,4}
IPV6ADDR = (
(IPV6SEG:){7,7}IPV6SEG| # 1:2:3:4:5:6:7:8
(IPV6SEG:){1,7}:| # 1:: 1:2:3:4:5:6:7::
(IPV6SEG:){1,6}:IPV6SEG| # 1::8 1:2:3:4:5:6::8 1:2:3:4:5:6::8
(IPV6SEG:){1,5}(:IPV6SEG){1,2}| # 1::7:8 1:2:3:4:5::7:8 1:2:3:4:5::8
(IPV6SEG:){1,4}(:IPV6SEG){1,3}| # 1::6:7:8 1:2:3:4::6:7:8 1:2:3:4::8
(IPV6SEG:){1,3}(:IPV6SEG){1,4}| # 1::5:6:7:8 1:2:3::5:6:7:8 1:2:3::8
(IPV6SEG:){1,2}(:IPV6SEG){1,5}| # 1::4:5:6:7:8 1:2::4:5:6:7:8 1:2::8
IPV6SEG:((:IPV6SEG){1,6})| # 1::3:4:5:6:7:8 1::3:4:5:6:7:8 1::8
:((:IPV6SEG){1,7}|:)| # ::2:3:4:5:6:7:8 ::2:3:4:5:6:7:8 ::8 ::
fe80:(:IPV6SEG){0,4}%[0-9a-zA-Z]{1,}| # fe80::7:8%eth0 fe80::7:8%1 (link-local IPv6 addresses with zone index)
::(ffff(:0{1,4}){0,1}:){0,1}IPV4ADDR| # ::255.255.255.255 ::ffff:255.255.255.255 ::ffff:0:255.255.255.255 (IPv4-mapped IPv6 addresses and IPv4-translated addresses)
(IPV6SEG:){1,4}:IPV4ADDR # 2001:db8:3:4::192.0.2.33 64:ff9b::192.0.2.33 (IPv4-Embedded IPv6 Address)
)
Ho pubblicato uno script su GitHub che verifica l'espressione regolare: https://gist.github.com/syzdek/6086792