Check Private IP

The is_private_ip function checks whether an IP address belongs to a private or reserved range. Supports both IPv4 and IPv6. Returns NULL for invalid addresses.

D SELECT is_private_ip('192.168.1.1');
┌──────────────────────────────┐
│ is_private_ip('192.168.1.1') │
│           boolean            │
├──────────────────────────────┤
│ true                         │
└──────────────────────────────┘

D SELECT is_private_ip('8.8.8.8');
┌──────────────────────────┐
│ is_private_ip('8.8.8.8') │
│         boolean          │
├──────────────────────────┤
│ false                    │
└──────────────────────────┘

D SELECT is_private_ip('fe80::1');
┌──────────────────────────┐
│ is_private_ip('fe80::1') │
│         boolean          │
├──────────────────────────┤
│ true                     │
└──────────────────────────┘

IPv4 Private/Reserved Ranges

Range	Description	RFC
10.0.0.0/8	Private network	RFC 1918
172.16.0.0/12	Private network	RFC 1918
192.168.0.0/16	Private network	RFC 1918
127.0.0.0/8	Loopback	RFC 1122
169.254.0.0/16	Link-local (APIPA)	RFC 3927
0.0.0.0/8	Current network	RFC 1122
100.64.0.0/10	Carrier-grade NAT	RFC 6598
192.0.0.0/24	IETF Protocol Assignments	RFC 6890
192.0.2.0/24	Documentation (TEST-NET-1)	RFC 5737
198.51.100.0/24	Documentation (TEST-NET-2)	RFC 5737
203.0.113.0/24	Documentation (TEST-NET-3)	RFC 5737
198.18.0.0/15	Benchmarking	RFC 2544
224.0.0.0/4	Multicast	RFC 5771
240.0.0.0/4	Reserved for future use	RFC 1112
255.255.255.255/32	Broadcast	RFC 919

IPv6 Private/Reserved Ranges

Range	Description	RFC
::1/128	Loopback	RFC 4291
::/128	Unspecified	RFC 4291
fe80::/10	Link-local	RFC 4291
fc00::/7	Unique local address (ULA)	RFC 4193
ff00::/8	Multicast	RFC 4291
2001:db8::/32	Documentation	RFC 3849
100::/64	Discard prefix	RFC 6666

For IPv4-mapped IPv6 addresses (::ffff:x.x.x.x), the function checks the embedded IPv4 address against the IPv4 private ranges listed above.