dns/libpsl 0.21.5_2 DragonFly

A "public suffix" is a domain name under which Internet users can directly register own names.

Browsers and other web clients can use it to

• avoid privacy-leaking "supercookies"
• avoid privacy-leaking "super domain" certificates [1]
• domain highlighting parts of the domain in a user interface
• sorting domain lists by site

Libpsl...

• has built-in PSL data for fast access
• allows to load PSL data from files
• checks if a given domain is a "public suffix"
• provides immediate cookie domain verification
• finds the longest public part of a given domain
• finds the shortest private part of a given domain
• works with international domains (UTF-8 and IDNA2008 Punycode)
• is thread-safe
• handles IDNA2008 UTS#46 (libicu is used by psl2c if installed)

[1] http://lists.gnu.org/archive/html/bug-wget/2014-03/msg00093.html