Miscellaneous Hacks - IPV6 Support in VB3

UPDATE - This mod works with vBulletin 3 AND vBulletin 4!

About

Ok, so let's get started. Got a web server that resolves IP addresses as ipv6? Don't want to remove that ipv6 functionality just so vBulletin will work well? Well, this mod will take care of all of that for you.

How it works

vBulletin 3 and 4 are (from a coding standpoint) completely reliant upon ipv4. Classes are coded all over the place which expect addresses to be in ipv4 format. This mod runs before ANYTHING in vB gets a chance to load and does the following:

- If the address is in ipv4-over-ipv6 format, it simply dumps the ipv4 portion of the address into vbulletin. Done. Simple as pie.
- If the address is in standard ipv6 format (it's a real ipv6 address), it generates a "psudo-ipv4" address to represent the ipv6 address. This "psudo-ipv4" address is in a reserved ipv4 address space, so it shouldn't interfere with any of the real ipv4 addresses, and is generated from a hash of the ipv6 address (so each of the ipv6 addresses should hopefully resolve to their own, unique ipv4 address).

And... that's about it! vB continues on it's merry way treating everyone's ip as a standard ipv4 address.

WATCH OUT!

See someone on your forum with an IP address starting in 204. after installing this mod? That means they are actually accessing your site via an ipv6 address, and the address LISTED doesn't really mean anything.

Installation

Not scared about what we just covered? Good, let's get started.

1. Upload ipv6_fix.php to your forum/includes directory.
2. Edit your includes/init.php file (VERY carefully)

Find

require_once(CWD . '/includes/class_core.php');

And insert JUST ABOVE IT

require_once(CWD . '/includes/ipv6_fix.php');

3. Every time you upgrade vB, repeat step 2.

And you're done!

This mod should have no effect if your web server is handling connections as ipv4 addresses. [S]This mod is no replacement for the REAL ipv6 support coming in vB4, so upgrade as soon as it is released![/S] Looks like ipv6 didn't make it into vB4 either -- On lives the mod!

Have fun

[flapjack]

Nifty little code, actually.

I don't know anyone who's using ipv6 yet, so it's no use to me, but I thought I'd give you kudos for working on this.

[accludetuner]

IPv6 is right around the corner. Installing now. Thanks

[heugabel]

thank you

[digibyte]

Vote for IPv6 support in vBulletin: http://tracker.vbulletin.com/browse/VBIV-9397

[PossumX]

Originally Posted by digibyte

Vote for IPv6 support in vBulletin: http://tracker.vbulletin.com/browse/VBIV-9397

Well, now they may do something about this, but, then again, who knows. Until supported natively by vB4, I have installed this simple work around. Thanks!!

Oh yeah, click on the vB tracker link and VOTE, as the fact that this has yet to even be scheduled (or at least planned to be) seems a bit inane for the "...largest international developer and distributor of proprietary community bulletin board software." (quoted from IB's site: http://www.internetbrands.com/our-brands/licensing/ )

[Monarch.V]

:up: Thanks

[traen]

Installed on 4.1.1 thanks.

[empire10]

Unfortunately this does not work anymore in 4.2. Is there any other workaround to use?

[GHDpro]

Originally Posted by empire10

Unfortunately this does not work anymore in 4.2. Is there any other workaround to use?

I've just hacked together the following, which seems to be working (in vB 4.2):

PHP Code:

function FixIPv6($ip) {
  // No colon = No IPv6 (return unaltered)
  if (stristr($ip,':') === false)
    return $ip;
  // Remove IPv6 encapsulation from IPv4 address
  if (strtolower(substr($ip,0,7)) == '::ffff:')
    return substr($ip,7);
  // Else: Pack IPv6 address into IPv4 address
  $crc = sprintf('%x',crc32($ip));
  $b = ord(pack('H*',substr($crc,0,2)));
  $c = ord(pack('H*',substr($crc,2,2)));
  $d = ord(pack('H*',substr($crc,4,2)));
  $ip = '10.'.$b.'.'.$c.'.'.$d;
  return $ip;
}

$_SERVER['REMOTE_ADDR'] = FixIPv6($_SERVER['REMOTE_ADDR']);
$this->ipaddress = FixIPv6($this->ipaddress); 


Put above code somewhere in /includes/config.php (the normal vB config file), for example just before the last line (with ?>).

Warning: you might want to make a backup of the config file as messing up editing it will probably cause your forum to stop loading (just blank pages).

I'm also not 100% sure if putting the hack in config.php is quite the right location, as ideally it should of course be run before any vB code that uses IP addresses. But (in v4.2) at least the config file is included (executed) right before the IPADDRESS constant is defined (from the $this->ipaddress variable), so it should work alright.

My main motivation for trying to put it in the config file is that you can now easily upgrade your forum without the need to re-apply the hacks to init.php (which the plugin does require every time).

Note that in my solution I've changed the way IPv6 addresses are encoded; so encoded IPv6 will not look the same as the plugin.