[NTLUG:Discuss] VPN Masquerading and RedHat 6.1

[Bob Byron]

Has anyone implemented VPN masquerading on RedHat 6.1.
I have read the Linux VPN Masquerade HowTo, but am unfortunately
confused by its instructions.  Mostly, the HowTo is written very broadly
to accommodate various versions of Linux and various connection
architectures.  I have Kernel 2.2.12 and I am using ipchains as a 
firewall.  I have a private network and would like various private pc's 
to connect to various VPN servers.

  Private
198.168.*.*
          PC1 --,                                            ,---VPN  a.com
          PC2 --Linux Firewall------(Internet)----VPN  b.com
          PC3 --'                                             '---VPN c.com

PC1 might connect to VPN c.com
PC2 might connect to VPN b.com
PC3 might connect to VPN a.com

I do not want the firewall to be the client.  I want the PC's to be the
client connecting through the firewall.  I do not want PC1 to be able
to piggyback on the VPN connection between PC3 and its connection
to a.com.  

I am new at Linux administration and need some questions answered.

1) Given the above architecture, do I want to use ipportfw?  It seems to me
the ipportfw setup is designed to route all VPN connections requests to a
single pc, not multiple like I have in the above scenario.
2) Does the 2.2.12 kernel have everything I need or is a recompile of the
kernel necessary?  I am leaning towards recompiling and including the
ip_masq_vpn module.

Thank You,
Bob Byron
RAD Systems, Inc.
www.radit.com
(972)516-4256