mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-08-22 07:43:22 +02:00
debate was from Paul Vixie, who wanted INET to be the name covering both IPV4 and IPV6. The following kit makes the needed changes: Tom Ivar Helbekkmo
75 lines
3.9 KiB
Plaintext
75 lines
3.9 KiB
Plaintext
PostgreSQL type extensions for IP and MAC addresses.
|
|
---------------------------------------------------
|
|
|
|
$Id: README.inet,v 1.1 1998/10/08 00:19:32 momjian Exp $
|
|
|
|
I needed to record IP and MAC level ethernet addresses in a data
|
|
base, and I really didn't want to store them as plain strings, with
|
|
no enforced error checking, so I put together the accompanying code
|
|
as my first experiment with adding a data type to PostgreSQL. I
|
|
then thought that this might be useful to others, both directly and
|
|
as a very simple example of how to do this sort of thing, so I
|
|
submitted it to the PostgreSQL project for inclusion in the contrib
|
|
directory. Since then, that directory has been modified to contain
|
|
Aleksei Roudnev's implementation, which is based on mine.
|
|
|
|
For those who have seen my previous contribution of these types, note
|
|
that much has changed: I've modified the IP address type to work the
|
|
way Paul Vixie did with his CIDR type. In fact, I've pretty much just
|
|
stolen his solution, modifying it into my framework in such a way as
|
|
to facilitate the addition of IPV6 handling code in the future. I've
|
|
pretty much ignored Aleksei's C code, but I've added his SQL code to
|
|
enter the necessary operators into the various system tables needed to
|
|
make the types indexable.
|
|
|
|
IP addresses are implemented as a struct of fixed in-memory length,
|
|
but variable on-disk storage size. For IPV4, it contains the address
|
|
family (AF_INET), the CIDR prefix length and four byte address. For
|
|
IPV6, the address family will be different, and the address longer.
|
|
|
|
The external representation of an IP address generally looks like
|
|
'158.37.96.15/32'. This address happens to be part of a subnet where
|
|
I work; '158.37.96.0/24', which itself is a part of the larger subnet
|
|
allocated to our site, which is '158.37.96.0/21', which again, if you
|
|
go by the old book, is part of the class "B" net '158.37.0.0/16'.
|
|
|
|
Input and output functions are supplied, along with the "normal" <,
|
|
<=, =, >=, > and <> operators, which all do what you expect. In
|
|
addition, there are operators to check for networks or addresses being
|
|
subnets of or addresses contained within other networks. << tests
|
|
whether the left operand is contained within the right, <<= includes
|
|
equality, >> and >>= do the same things the opposite way.
|
|
|
|
The input and output functions use routines from Paul Vixie's BIND,
|
|
and I've snarfed the source files inet_net_ntop.c and inet_net_pton.c
|
|
directly from a recent distribution of that code. They are included
|
|
here to avoid the need to fetch and install the BIND libraries to be
|
|
able to use this code. IANAL, but it looks from the copyright
|
|
messages in the files as if this should be acceptable. Read the
|
|
documentation in inet_net_pton.c to see the legal input formats.
|
|
|
|
MAC level ethernet addresses are implemented as a 6 byte struct that
|
|
contains the address as unsigned chars. Several input forms are
|
|
accepted; the following are all the same address: '08002b:010203',
|
|
'08002b-010203', '0800.2b01.0203', '08-00-2b-01-02-03' and
|
|
'08:00:2b:01:02:03'. Upper and lower case is accepted for the digits
|
|
'a' through 'f'. Output is always in the latter of the given forms.
|
|
|
|
As with IP addresses, input and output functions are supplied as well
|
|
as the "normal" operators, which do what you expect. As an extra
|
|
feature, a function macaddr_manuf() is defined, which returns the name
|
|
of the manufacturer as a string. This is currently held in a
|
|
hard-coded struct internal to the C module -- it might be smarter to
|
|
put this information into an actual data base table, and look up the
|
|
manufacturer there.
|
|
|
|
Many thanks to Aleksei Roudnev and Paul Vixie for their fine work!
|
|
|
|
I don't know what changes are needed to the Makefile for other systems
|
|
than the one I'm running (NetBSD 1.3), but anyway: to install on a BSD
|
|
system: fix the path names in the Makefile if you need to, then make,
|
|
make install, slurp the SQL files into psql or whatever, and you're
|
|
off. Enjoy!
|
|
|
|
Bergen, Norway, 1998-08-09, Tom Ivar Helbekkmo (tih@nhh.no).
|