Make is_global/is_unicast_global special address handling complete

IANA explicitly documents 192.0.0.9/32, 192.0.0.9/32 and 2001:30::/28 as
globally reachable[1][2] and the is_global implementations declare
following IANA so let's make this happen.

In case of 2002::/16 IANA says N/A so I think it's safe to say we
shouldn't return true from is_global and is_unicast_global either for
addresses in that block.

[1] https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml
[2] https://www.iana.org/assignments/iana-ipv6-special-registry/iana-ipv6-special-registry.xhtml

library/core/src/net/ip_addr.rs

@@ -771,7 +771,11 @@ impl Ipv4Addr {
  || self.is_loopback()
  || self.is_link_local()
  // addresses reserved for future protocols (`192.0.0.0/24`)
- ||(self.octets()[0] == 192 && self.octets()[1] == 0 && self.octets()[2] == 0)
+ // .9 and .10 are documented as globally reachable so they're excluded
+ || (
+ self.octets()[0] == 192 && self.octets()[1] == 0 && self.octets()[2] == 0
+ && self.octets()[3] != 9 && self.octets()[3] != 10
+ )
  || self.is_documentation()
  || self.is_benchmarking()
  || self.is_reserved()
@@ -1515,8 +1519,12 @@ impl Ipv6Addr {
  // AS112-v6 (`2001:4:112::/48`)
  || matches!(self.segments(), [0x2001, 4, 0x112, _, _, _, _, _])
  // ORCHIDv2 (`2001:20::/28`)
- || matches!(self.segments(), [0x2001, b, _, _, _, _, _, _] if b >= 0x20 && b <= 0x2F)
+ // Drone Remote ID Protocol Entity Tags (DETs) Prefix (`2001:30::/28`)`
+ || matches!(self.segments(), [0x2001, b, _, _, _, _, _, _] if b >= 0x20 && b <= 0x3F)
  ))
+ // 6to4 (`2002::/16`) – it's not explicitly documented as globally reachable,
+ // IANA says N/A.
+ || matches!(self.segments(), [0x2002, _, _, _, _, _, _, _])
  || self.is_documentation()
  || self.is_unique_local()
  || self.is_unicast_link_local())
@@ -1684,6 +1692,7 @@ impl Ipv6Addr {
  /// - unique local addresses
  /// - the unspecified address
  /// - the address range reserved for documentation
+ /// - 6to4 addresses
  ///
  /// This method returns [`true`] for site-local addresses as per [RFC 4291 section 2.5.7]
  ///
@@ -1717,6 +1726,8 @@ impl Ipv6Addr {
  && !self.is_unspecified()
  && !self.is_documentation()
  && !self.is_benchmarking()
+ // 6to4 (`2002::/16`), not documented as globally reachable by IANA
+ && self.segments()[0] != 0x2002
  }
 
  /// Returns the address's multicast scope if the address is multicast.

library/core/tests/net/ip_addr.rs

@@ -461,6 +461,9 @@ fn ipv4_properties() {
  check!("198.18.54.2", benchmarking);
  check!("198.19.255.255", benchmarking);
  check!("192.0.0.0");
+ check!("192.0.0.8");
+ check!("192.0.0.9", global);
+ check!("192.0.0.10", global);
  check!("192.0.0.255");
  check!("192.0.0.100");
  check!("240.0.0.0", reserved);
@@ -480,6 +483,10 @@ fn ipv6_properties() {
  }
 
  macro_rules! check {
+ ($s:expr, &[$($octet:expr),*]) => {
+ check!($s, &[$($octet),*], 0);
+ };
+
  ($s:expr, &[$($octet:expr),*], $mask:expr) => {
  assert_eq!($s, ip!($s).to_string());
  let octets = &[$($octet),*];
@@ -657,14 +664,16 @@ fn ipv6_properties() {
  global | unicast_global
  );
 
- check!("2001:30::", &[0x20, 1, 0, 0x30, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unicast_global);
+ check!("2001:30::", &[0x20, 1, 0, 0x30, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], global | unicast_global);
 
  check!(
  "2001:200::",
  &[0x20, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
  global | unicast_global
  );
 
+ check!("2002::", &[0x20, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]);
+
  check!("fc00::", &[0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], unique_local);
 
  check!(