The getaddrinfo and gethostbyname are used to return
address for a given hostname. The getnameinfo and gethostbyaddr are used to
return hostnem for a given address. Right now in Casper we have two
limitations: NAME which allows to resolve DNS names. ADDR which allows to do
revert DNS lookups.
Before this change the rights was mixed up:
NAME - getnameinfo and gethostbyname
ADDR - gethostbyaddr and getaddrinfo
Which no matters on limitation allowed us to resolve DNS names and do DNS lookups
basically by using different set of functions.
Now the NAME type allows getaddrinfo and gethostbyname functions, and the ADDR names
allows to use gethostbyaddr and getnameinfo functions.