1

This list of domains: https://publicsuffix.org/list/public_suffix_list.dat

The wildcard character * (asterisk) matches any valid sequence of characters in a hostname part. (Note: the list uses Unicode, not Punycode forms, and is encoded using UTF-8.) Wildcards are not restricted to appear only in the leftmost position, but they must wildcard an entire label. (I.e. ..foo is a valid rule: *bar.foo is not.)

Source: https://publicsuffix.org/list/

I've read the above and that whole page several times by now and don't understand it. I understand that the "!" entries mean "exceptions", but I don't get what the ones beginning with "*." mean, since that seems to be implied for all of them. After they, they are a list of "in practice" TLDs.

Their description only further confuses me. I don't understand what makes those entries different from all the of other ones.

Joeleen
  • 11
  • 1
  • To potentially clarify, the wildcard is part of the suffix. Ie, the registerable names are one level further down, under any number of not enumerated subdomains. – Håkan Lindqvist Feb 11 '20 at 08:07

1 Answers1

1

That list is a list of domains that should not have cookies because domains can be registered under them. For that purpose, there is a difference between example.com and *.example.com on that list.

When example.com is on the list, it means that cookies should NOT be allowed at example.com but SHOULD be allowed for sub.example.com, sub.sub.example.com, another.example.com and sub.another.example.com.

When *.example.com is on the list, it means that cookies should NOT be allowed at example.com, sub.example.com, or another.example.com but SHOULD be allowed for sub.sub.example.com and sub.another.example.com.

This is to account for when registration of sub-sub-domains is allowed but not the registration of sub-domains.

Patrick Mevzek
  • 8,375
  • 1
  • 20
  • 42
Stephen Ostermiller
  • 98,758
  • 18
  • 137
  • 361