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Date:      Fri, 26 Aug 2011 12:42:27 -0500
From:      jhall@socket.net
To:        mike@sentex.net
Cc:        freebsd-questions@freebsd.org
Subject:   Re: Re: Racoon to Cisco ASA 5505 
Message-ID:  <20110826174228.E7028106566C@hub.freebsd.org>
References:  <20110823232242.B78A5106566B@hub.freebsd.org> <4E545899.6090800@sentex.net> <20110825155205.A0D131065670@hub.freebsd.org> <4E5696D0.3000205@sentex.net>

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I am seeing a couple of things that are concerning me.  

First, I am not seeing any traffic over the gif interface, except return 
traffic.  For example if I ping from one of my sites (e.g. 
10.129.30.0/24), I do not see any traffic on the gif interface. 

Second, I am seeing the following error message, "Header checksum: 0X0000 
[incorrect, should be 0x8d84 (maybe caused by "IP Checksum Offload?)]. 

I spoke to our vendor this morning, an they are seeing encrypted packets 
flowing to them.  However, I am not able to ping their devices until they 
initiate the traffic.  This is when I am not seeing any traffic on the gif 
interface. 

Following are the policies I have defined for the 10.129.30 network.  All 
policies are a copy of these with the correct networks added. 

spdadd 10.129.30.0/24 192.168.100.0/22 any -P out ipsec 
esp/tunnel/1.1.1.1-184.106.120.244/use; 
spdadd 192.168.100.0/22 10.129.30.0/24 any -P in ipsec 
esp/tunnel/184.106.120.244-1.1.1.1/use; 
spdadd 184.106.120.244/32 10.129.30.0/24 any -P in ipsec 
esp/tunnel/184.106.120.244-1.1.1.1/use; 
spdadd 10.129.30.0/24 184.106.120.244/32 any -P out ipsec 
esp/tunnel/184.106.120.244-1.1.1.1/use; 

Thank you for all your help.  If you would like the results of the capture 
posted, please let me know and I will post them as well. 


Jay
----------------------------------------------------
>From : Mike Tancsa <mike@sentex.net>
To : jhall@socket.net
Subject : Re: Racoon to Cisco ASA 5505
Date : Thu, 25 Aug 2011 14:39:12 -0400
> On 8/25/2011 11:52 AM, jhall@socket.net wrote:
> >> I find wireshark helpful in these cases as it nicely decodes what
> >> options are being set.  Your racoon conf is set to obey. Its possible
> >> they are proposing something different to you that you accept, where 
as 
> >> what you are proposing might not be acceptable
> > 
> > My vendor came back to me today and stated they found a configuration 
> > error on their end.  Their most recent message states the traffic I am 
> > sending to them through the IPSec tunnel is not encrypted. 
> 
> What does your actual policy look like ? Is this the only ipsec config
> on your box ? If so, lets say your public IP is 1.1.1.1 and their ip is
> 184.106.120.244
> 
> try adding this to /etc/ipsec.conf
> 
> spdadd 10.129.30.0/24 192.168.100.0/22 any -P out ipsec
> esp/tunnel/1.1.1.1-184.106.120.244/unique;
> spdadd 192.168.100.0/22 10.129.30.0/24 any -P in  ipsec
> esp/tunnel/184.106.120.244-1.1.1.1/unique;
> 
> 
> 
> do a
> setkey -F
> setkey -FP
> setkey -f /etc/ipsec.conf
> 
> This is saying that you will create an ipsec policy between 2 networks.
> Your side behind 1.1.1.1 and their side behind 184.106.120.244.
> The policy states that packets with a source address of 10.129.30.0/24
> destined to 192.168.100.0/22 will be encapsulated in an ipsec tunnel.
> Similarly, everything going the other direction - 192.168.100.0/22 going
> to 10.129.30.0/24... And *only* those packets.  If you have a packet
> with a source address of 10.0.0.1 destined to 192.168.100.0/22, it will
> not be passed through the tunnel.
> 
> 
> > 
> > Following is what they sent me from the ASA.
> > 
> >  Crypto map tag: rackmap, seq num: 201, local addr: 184.106.120.244
> > 
> >       access-list 201 extended permit ip 192.168.100.0 255.255.252.0 
> > 10.129.30.0 255.255.255.0 
> >       local ident (addr/mask/prot/port): 
(192.168.100.0/255.255.252.0/0/0) 
> >       remote ident (addr/mask/prot/port): 
(10.129.30.0/255.255.255.0/0/0) 
> >       current_peer: Jefferson_City
> 
> 
> 
> You then need to make sure your key exchange settings agree. Ask them
> for that portion of the ASA's config.
> 
> You are proposing
> exchange_mode main,base,aggressive;
> You are known to them by IP (my_identifier address)
> You should probably add
> peers_identifier address;
> and then make sure in your psk.txt file you have something like
> 
> 184.106.120.244 the-secret-psk-you-agreed-on
> 
> Also, make sure their side is expecting 3des and hmac is sha1 or md5 as
> you posted in your original config.
> 
> 
> 
> On your public wan interface, do a tcpdump of the remote IP. e.g. if its
> em0, do
> 
> tcpdump -ni em0 -s0 -w /tmp/186.pcap host 184.106.120.244
> 
> 
> startup racoon with the debug flag
> and from your network, try and ping an IP in their private network from
> your private network
> 
> 
> e.g.
> ping -S 10.129.30.1 192.168.100.1
> 
> When testing ipsec, get in the habbit of ALWAYS specifying the source IP
> so that you know the packet you are generating falls within the policy
> you have specified.
> 
> If things dont work, look at the racoon logs for clues as well as look
> at the pcap afterwards with -vvvv
> tcpdump -vvvv -nr /tmp/186.pcap port 500
> 
> if it worked and you get a ping response, look at the full traffic to
> make sure its ESP and that the contents are indeed encrypted.
> 			
> 	---Mike
> 
> -- 
> -------------------
> Mike Tancsa, tel +1 519 651 3400
> Sentex Communications, mike@sentex.net
> Providing Internet services since 1994 www.sentex.net
> Cambridge, Ontario Canada   http://www.tancsa.com/




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