Re: PIX VPN Setup [7:74369]

2003-08-26 Thread Francisco Gomez
John,



One question at the time:



1)  "I noticed that I never set an isakmp pre-share key"



  - Remember that for a VPN client connection, ISAKMP or Phase I is
established using "aggressive mode" in this case and due the remote
connection would come from any place on the Internet; a pre-share key is not
used like in a L2L tunnel "isakmp key  etc... This is not a security
risk but if you want to be a little more specific, you can use digital
certificates, (rsa-signatures), so that will give you the opportunity to
"trust" more in the people getting connected. CRLs will be definitely
something I will suggest. For more details check this link:



http://www.cisco.com/warp/public/471/configipsecsmart.html



"...you can avoid the eToken part"



2)   In testing I tried to get all traffic to flow through the VPN but I
think the pix prevents  traffic coming in on the outside interface to leave
on that same  interface



  - The PIX firewall will never re-direct packets to the same interface they
have just arrived and this is in order to prevent IP spoofing, (that how ASA
works on the PIX). In the other hand, another interface is the solution for
this, but the 501 only comes with outside/inside, the four ports you see on
the back are all "inside", (this is an embedded switch for SOHO users). But
remember that if you have another interface on the PIX, (a 515 or 525), that
interface should be connected to another ISP and you'll need another default
gateway; another default gateway is something you cannot achieve unless you
are running 6.3.1 and enable OSPF for that device but then again, this is a
design I will not recommend.



Summarizing, go with "split-tunneling" or use a IOS router or VPN
concentrator and that will do the trick for you.



Finally and in regards with the config, everything looks ok, no need to have
more than one isakmp polices but if you wish you can leave things the way
they are. Hope this helps a little.





My two cents,



Frank

Costa Rica





 Original Message -
From: "John Cianfarani" 
To: 
Sent: Monday, August 25, 2003 6:25 PM
Subject: PIX VPN Setup [7:74369]


> I'm setting up a small VPN just for home use so me and a few friends can
> log in remotely via a PIX 501 w/ 3DES over my cable connection.
>
> Now I've got it working, but found a few strange things I had questions
> about.  I have each user setup with the VPNGROUP config lines. (I will
> post config below), everyone uses the Cisco VPN client to connect.  Now
> I noticed that I never set an isakmp pre-share key and there is no spot
> to add one in the Cisco client only user/pass I would think that should
> be needed for secure connectivety.  The other setup I did was have a
> split-tunnel applied to the user when they connect to only encrypt
> traffic destined for the local network and any regular internet traffic
> would still go out the persons internet connection.  In testing I tried
> to get all traffic to flow through the VPN but I think the pix prevents
> traffic coming in on the outside interface to leave on that same
> interface (as it would with internet traffic) . Any way to do this or do
> you need another interface?
> Also just wondering if there is a better way to write this config or any
> other tips are appreciated.
>
> Here is an edited config with only the relevant portions.
>
> Thanks for any help
> John
>
> PIX Version 6.3(1)
> !
> access-list 80 permit ip any host 192.168.1.75
> access-list 80 permit ip any host 192.168.1.76
> access-list 80 permit ip any host 192.168.1.77
> access-list 80 permit ip any host 192.168.1.78
> access-list 80 permit ip any host 192.168.1.79
> !
> access-list 90 permit ip 192.168.1.0 255.255.255.0 host 192.168.1.75
> access-list 90 permit ip 192.168.1.0 255.255.255.0 host 192.168.1.76
> access-list 90 permit ip 192.168.1.0 255.255.255.0 host 192.168.1.77
> access-list 90 permit ip 192.168.1.0 255.255.255.0 host 192.168.1.78
> access-list 90 permit ip 192.168.1.0 255.255.255.0 host 192.168.1.79
> !
> ip address outside dhcp setroute
> ip address inside 192.168.1.254 255.255.255.0
> ip local pool REMOTEUSER 192.168.1.75-192.168.1.79
> !
> global (outside) 1 interface
> nat (inside) 0 access-list 80
> nat (inside) 1 0.0.0.0 0.0.0.0 0 0
> floodguard enable
> !
> crypto ipsec transform-set TRANSFORM esp-3des esp-md5-hmac
> crypto dynamic-map DYNOMAP 10 set transform-set TRANSFORM
> crypto map MYMAP 100 ipsec-isakmp dynamic DYNOMAP
> crypto map MYMAP interface outside
> !
> isakmp enable outside
> isakmp identity address
> isakmp policy 10 authentication pre-share
> isakmp policy 10 encryption 3des
> isakmp policy 10 hash sha
> isakmp policy 10 group 2
> isakmp policy 10 lifetime 86400
> isakmp policy 20 authentication pre-share
> isakmp policy 20 encryption des
> isakmp policy 20 hash sha
> isakmp policy 20 group 1
> isakmp policy 20 lifetime 86400
> isakmp policy 30 authentication pre-share
> isakmp policy 30 encryption 3des
> isakmp policy 30 hash md5
> isakmp pol

RE: PIX VPN Setup [7:74369]

2003-09-02 Thread Deepali S
Hi! John,

 The isakmp and pre-share key is used only when you have the L2L tunnel
setup.
 When you have a VPN tunnel between Client and PIX , the command below is
same as the isakmp and pre-shared key.

 vpngroup VPNUSER password  
 
 Spli tunneling is used when you want the user to browse the internet when
he still has a VPN tunnel established.

 Pls check this link to know more abt split tunneling: 

 http://www.cisco.com/warp/public/707/ipsec_debug.html#inability

 Let me know if you have any queries.


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