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As I said before, tunnel status is almost impossible to obtain.<br>
<br>
You can see the encryption being used in /var/log/secure. You are
using AES128, modp2048 and SHA1 which is OK<br>
<br>
Your conns look absolutely fine and your tunnel is up. You have not
explicitly defined the encryption so it has chosen a reasonable one
(similar in strength to 3des but uses 1/3 cpu cycles). You don't
need virtual_private with your set up and you don't need protocols
50 and 51 through the firewall as ipsec with NAT-T is working.<br>
<br>
Neal's summary was pretty much spot on.<br>
<br>
Can you confirm you don't have a blank line after conn ...... and
before type=tunnel in your conf files?<br>
<br>
Can you do the traceroutes/tracerts I asked for?<br>
<br>
Nick<br>
<br>
<div class="moz-cite-prefix">On 20/11/2013 20:07, Neal Murphy wrote:<br>
</div>
<blockquote cite="mid:201311201507.03243.neal.p.murphy@alum.wpi.edu"
type="cite">
<pre wrap="">On Wednesday, November 20, 2013 02:48:11 PM Fred Weston wrote:
</pre>
<blockquote type="cite">
<pre wrap="">All of this makes sense to me and I believe I have crossed everything you
listed off my troubleshooting list.
Is there a way to see the status of the tunnel and what crypto is being
used to transmit packets between LANs?
</pre>
</blockquote>
<pre wrap="">
If openswan is running on GNU/Linux and you are using KLIPS,
cd /proc/net
for i in ipsec_*; do
echo $i
sed -e 's/^/ /' $i
done
And peruse /proc/net/ipsec/.
To obtain a deluge of info, '/usr/sbin/ipsec barf'.
</pre>
<blockquote type="cite">
<pre wrap="">
-----Original Message-----
From: <a class="moz-txt-link-abbreviated" href="mailto:users-bounces@lists.openswan.org">users-bounces@lists.openswan.org</a>
[<a class="moz-txt-link-freetext" href="mailto:users-bounces@lists.openswan.org">mailto:users-bounces@lists.openswan.org</a>] On Behalf Of Neal Murphy Sent:
Wednesday, November 20, 2013 2:12 PM
To: <a class="moz-txt-link-abbreviated" href="mailto:users@openswan.org">users@openswan.org</a>
Subject: Re: [Openswan Users] Firewall rules for openswan behind NAT
You've addressed some or most of what's in the following bird's-eye view;
it shouldn't hurt to review in case you've overlooked something.
You need to forward UDP ports 500 and 4500 on each firewall to the local
openswan box (limit it to coming from the remote IP/openswan box for added
security), and allow UDP ports 500 and 4500 out from the local openswan
box (preferably limit it to going to the remote openswan box for added
security). This will allow either end to start the VPN. Each firewall
should drop packets destined for the remote LAN(s) since they don't know
how to reach them. Logging them with a specific prefix would make it easy
to discover malconfigured nodes.
I don't believe protocols 50 and 51 are used when NAT-T is used.
Each internal node must have an explicit route to the remote LAN via the
local openswan box's IP.
Each openswan box needs route(s) to the local internal LAN(s) and a default
route via the local firewall's internal IP address. Openswan takes care of
adding/removing routes to remote LANs when it brings VPNs up and down.
Do you have a 'config setup' in each ipsec.conf, possibly similar to:
protostack=klips # or netkey or mast
interfaces=%defaultroute
klipsdebug=none
plutodebug=none
plutowait=no
uniqueids=yes
nat_traversal=yes
You might need a virtual_private declaration describing your internal LANs,
but probably not, since you aren't using a road warrior setup.
In each conn spec, you may need to specify ike= and esp=; that is, tell
openswan which encrytpion to use. I don't know what happens if you don't
specify any encryption methods. (Does openswan then transmit in the
clear?)
I haven't played with NAT Traversal lately; I forget how to configure a
conn to make NAT-T work.
N
On Wednesday, November 20, 2013 12:28:35 PM Fred Weston wrote:
</pre>
<blockquote type="cite">
<pre wrap="">I cannot ping LAN-LAN without the tunnel.
In site A I have 10.0.0.0/16 and in site B I have 10.1.0.0/16. In
each site the routing table has an entry for the opposite site’s IP
space which is pointed at the local openswan box.
I think we are confusing firewall and tunnel terminology. The
firewall I am speaking of is builtin to AWS and controls ingress and
egress traffic from the openswan boxes. It is something that is part
of the AWS network stack and the only thing I can do to it is change its
ruleset.
The traffic between sites is traversing the openswan tunnel, however
when it’s doing so it isn’t being encrypted, so for instance when I
send RDP traffic across the tunnel, the AWS firewall sees RDP traffic
and doesn’t let it through. If the tunnel were encrypting traffic,
all the AWS firewall should see is UDP traffic coming into port 500
and it should have no idea what that traffic is, but it’ll allow it
because I’ve told it to permit udp/500 inbound.
In the diagram below I’ve notated where the AWS firewall at each site
is inspecting traffic. The issue is that the traffic coming across
the tunnel is in the clear.
[<a class="moz-txt-link-freetext" href="cid:image002.jpg@01CEE5EC.06F0A5C0">cid:image002.jpg@01CEE5EC.06F0A5C0</a>]
From: Nick Howitt [<a class="moz-txt-link-freetext" href="mailto:n1ck.h0w1tt@gmail.com">mailto:n1ck.h0w1tt@gmail.com</a>]
Sent: Wednesday, November 20, 2013 3:36 AM
To: Fred Weston
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a>
Subject: Re: [Openswan Users] Firewall rules for openswan behind NAT
I am curious that your are even pinging LAN-LAN outside the tunnel.
You have private subnets and the internet would not know where to find
a 10.x.y.z address. Can you do a tracert/traceroute end to end with
and without the firewall?
On your gateways to you have routes set up to your far LAN's via your
Openswan devices?
Can you ping from 10.0.0.82 to 10.1.0.67 or vice-versa with the
firewall up and down?
On 2013-11-19 17:14, Fred Weston wrote:
The tunnel comes up either way but I can't ping unless I permit icmp
from the Internet into openswan. I'm pinging from another device
behind openswan.
Thanks ,
FW
On Nov 19, 2013, at 11:40 AM, "Nick Howitt"
<<a class="moz-txt-link-abbreviated" href="mailto:n1ck.h0w1tt@gmail.com">n1ck.h0w1tt@gmail.com</a><a class="moz-txt-link-rfc2396E" href="mailto:n1ck.h0w1tt@gmail.com"><mailto:n1ck.h0w1tt@gmail.com></a>> wrote:
OK that shows the tunnel is up. Is that with or without the firewall
(and btw it is using NAT-T so you should not need protocols 50 and 51
through your firewall).
When you are pinging end to end, is that from the openswan device or
from another LAN device?
On 2013-11-19 14:03, Fred Weston wrote:
This is what I see in the log; it looks like it’s encrypting traffic
but that doesn’t seem to be the case based upon the behavior I’m
seeing. If it is encrypting then the firewall in front of openswan
should have no effect on the traffic I can pass over the tunnel as
long as the tunnel is up.
Nov 19 14:00:55 ip-10-0-0-82 pluto[12517]: "vpc1-to-vpc2" #1:
NAT-Traversal: Result using RFC 3947 (NAT-Traversal): both are NATed
Nov
19 14:00:55 ip-10-0-0-82 pluto[12517]: "vpc1-to-vpc2" #1: transition
from state STATE_MAIN_I2 to state STATE_MAIN_I3 Nov 19 14:00:55
ip-10-0-0-82
pluto[12517]: "vpc1-to-vpc2" #1: STATE_MAIN_I3: sent MI3, expecting
MR3 Nov 19 14:00:55 ip-10-0-0-82 pluto[12517]: "vpc1-to-vpc2" #1:
received Vendor ID payload [CAN-IKEv2] Nov 19 14:00:55 ip-10-0-0-82
pluto[12517]: "vpc1-to-vpc2" #1: Main mode peer ID is ID_IPV4_ADDR:
'50.18.211.121' Nov
19 14:00:55 ip-10-0-0-82 pluto[12517]: "vpc1-to-vpc2" #1: transition
from state STATE_MAIN_I3 to state STATE_MAIN_I4 Nov 19 14:00:55
ip-10-0-0-82
pluto[12517]: "vpc1-to-vpc2" #1: STATE_MAIN_I4: ISAKMP SA established
{auth=OAKLEY_PRESHARED_KEY cipher=aes_128 prf=oakley_sha
group=modp2048} Nov 19 14:00:55 ip-10-0-0-82 pluto[12517]:
"vpc1-to-vpc2" #2: initiating Quick Mode
PSK+ENCRYPT+TUNNEL+PFS+UP+IKEv2ALLOW+SAREFTRACK {using isakmp#1
msgid:463435ec proposal=defaults pfsgroup=OAKLEY_GROUP_MODP2048} Nov
19
14:00:56 ip-10-0-0-82 pluto[12517]: "vpc1-to-vpc2" #2: transition from
state STATE_QUICK_I1 to state STATE_QUICK_I2 Nov 19 14:00:56
ip-10-0-0-82
pluto[12517]: "vpc1-to-vpc2" #2: STATE_QUICK_I2: sent QI2, IPsec SA
established tunnel mode {ESP=>0x54dd12fe <0x2bb3e074
xfrm=AES_128-HMAC_SHA1 NATOA=none NATD=50.18.211.121:4500 DPD=none}
From: Nick Howitt [<a class="moz-txt-link-freetext" href="mailto:n1ck.h0w1tt@gmail.com">mailto:n1ck.h0w1tt@gmail.com</a>]
Sent: Tuesday, November 19, 2013 8:21 AM
To: Fred Weston
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users@lists.openswan.org"><mailto:users@lists.openswan.org></a>
Subject: RE: [Openswan Users] Firewall rules for openswan behind NAT
What are you getting in /var/log/secure - just the bit where the
tunnel is negotiating, not the bit where ipsec loads?
Also what do you have in the "config setup" sections of your conf files?
On 2013-11-19 13:14, Fred Weston wrote:
So here’s something interesting…this morning just for the heck of it,
I added ICMP to the permit list and that immediately got ping working.
Since the tunnel shouldn’t require ICMP, that got me thinking that the
traffic isn’t actually being encrypted. I verified that by trying to
remote desktop to a host on the far side of the tunnel. It didn’t
work when I have the firewall rules set to only allow the few
ports/protocols the tunnel should need, but as soon as I changed the
ruleset to permit all traffic RDP worked, so it seems the problem is
actually that the tunnel isn’t encrypting the traffic.
I’m not quite sure why this is.
Here are the configs from each side, can someone comment as to what I
need to add to get the traffic to be encrypted?
conn vpc1-to-vpc2
type=tunnel
authby=secret
left=%defaultroute
leftid=107.21.17.86
leftnexthop=%defaultroute
leftsubnet=10.0.0.0/16
leftsourceip=10.0.0.82
right=50.18.211.121
rightsubnet=10.1.0.0/16
pfs=yes
auto=start
phase2=esp
conn vpc2-to-vpc1
type=tunnel
authby=secret
left=%defaultroute
leftid=50.18.211.121
leftnexthop=%defaultroute
leftsubnet=10.1.0.0/16
leftsourceip=10.1.0.67
right=107.21.17.86
rightsubnet=10.0.0.0/16
pfs=yes
auto=start
phase2=esp
From: Nick Howitt [<a class="moz-txt-link-freetext" href="mailto:n1ck.h0w1tt@gmail.com">mailto:n1ck.h0w1tt@gmail.com</a>]
Sent: Tuesday, November 19, 2013 5:19 AM
To: Fred Weston
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users@lists.openswan.org"><mailto:users@lists.openswan.org></a>
Subject: RE: [Openswan Users] Firewall rules for openswan behind NAT
Yes, I was picturing firewalling in the hosts.
Have a look in the logs and see if Openswan is connecting with or
without NAT-T when your firewall is not up. Then, with your
firewalling, try forceencaps=yes in the conn and nat_traversal=yes in
config setup.
For minor tunnel info I use "service ipsec status", but it depends on
your distro and the information is almost useless. You can also have a
look at "ip xfrm" and "ip route".
Nick
On 2013-11-19 10:03, Fred Weston wrote:
I think you’re picturing the firewalling taking place on the openswan
hosts, which isn’t the case. There isn’t a firewall on either
openswan box (other than any standard firewall that may be enabled by
default). The firewall rules I am manipulating are in the network / NAT
device in front of openswan. Since the tunnel works when I permit all
traffic to openswan, that would seem to discount the possibility of
any firewall issues on the hosts themselves.
I’ll take a look at the logs to see if they show anything interesting.
Is there a utility that will show tunnel status?
From: Nick Howitt [<a class="moz-txt-link-freetext" href="mailto:n1ck.h0w1tt@gmail.com">mailto:n1ck.h0w1tt@gmail.com</a>]
Sent: Tuesday, November 19, 2013 3:44 AM
To: Fred Weston
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users@lists.openswan.org"><mailto:users@lists.openswan.org></a>
Subject: RE: [Openswan Users] Firewall rules for openswan behind NAT
For your rules, I was hoping for something like the output to
"iptables -L -n -v" and "iptables -t nat -L -n -v" rather than a
description of the rules.
Forceencaps is unlikely but can be useful
Openswan/ipsec logs are typically found in /var/log/secure depending
on your system. If you have dpd enabled you should see constant tunnel
renegotiation if the tunnel has gone down. You'll see nothing odd if
the tunnel is up but no traffic is passing. When the tunnel is up you
should see in the logs something like "IPSec SA Established".
Available status information is not particulrly helpful.
Can you also try adding a firewall rule something like:
iptables -t nat -I POSTROUTING -m policy --dir out --pol ipsec -j
ACCEPT
Either that or somthing in the post routing chain which allows traffic
between the local and remote subnets, but this rule is more flexible
as you don't need to specify the subnets.
Nick
On 2013-11-18 23:28, Fred Weston wrote:
From:
<a class="moz-txt-link-abbreviated" href="mailto:users-bounces@lists.openswan.org">users-bounces@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users-bounces@lists.openswan.org"><mailto:users-bounces@lists.openswan.o
rg></a> [<a class="moz-txt-link-freetext" href="mailto:users-bounces@lists.openswan.org">mailto:users-bounces@lists.openswan.org</a>] On Behalf Of Nick Howitt
Can you post the exact rules you are using?
I included those in my original message.
*:* > UDP 500
*:* > UDP 4500
* > IP Protocol 50
* > IP Protocol 51
Also have you tried forcing encapsulation with forceencaps=yes in your
conns?
No, I haven’t tried that.
When you say "things stop working" does the tunnel come down, or does
traffic just fail to pass?
I’m not sure how to tell the difference, my test methodology was to
ping a host on the far side of the tunnel and when I change the
firewall rules from wide open to those above the ping starts timing
out. How can I tell what state the tunnel is in?
Regards,
Nick
On 2013-11-17 17:13, Fred Weston wrote:
Does anyone else have any suggestions? I would like to implement this
in production but I am hesitant to do so when the only way I can get
it to work is permit all traffic from the Internet into the openswan
boxes.
From:
<a class="moz-txt-link-abbreviated" href="mailto:users-bounces@lists.openswan.org">users-bounces@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users-bounces@lists.openswan.org"><mailto:users-bounces@lists.openswan.o
rg></a> [<a class="moz-txt-link-freetext" href="mailto:users-bounces@lists.openswan.org">mailto:users-bounces@lists.openswan.org</a>] On Behalf Of Fred Weston
Sent:
Wednesday, November 13, 2013 11:49 AM
To: Leto
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users@lists.openswan.org"><mailto:users@lists.openswan.org></a>
Subject: Re: [Openswan Users] Firewall rules for openswan behind NAT
Let me clarify – when I reference ports/protocols that I’m allowing
inbound, I’m allowing it from the opposite host and not specifying a
source port.
Thanks,
FW
From: Leto [<a class="moz-txt-link-freetext" href="mailto:letoams@gmail.com">mailto:letoams@gmail.com</a>]
Sent: Wednesday, November 13, 2013 11:27 AM
To: Fred Weston
Cc: <a class="moz-txt-link-abbreviated" href="mailto:users@lists.openswan.org">users@lists.openswan.org</a><a class="moz-txt-link-rfc2396E" href="mailto:users@lists.openswan.org"><mailto:users@lists.openswan.org></a>
Subject: Re: [Openswan Users] Firewall rules for openswan behind NAT
sent from a tiny device
On 2013-11-13, at 10:44, Fred Weston
<<a class="moz-txt-link-abbreviated" href="mailto:fred.weston@lpga.com">fred.weston@lpga.com</a><a class="moz-txt-link-rfc2396E" href="mailto:fred.weston@lpga.com"><mailto:fred.weston@lpga.com></a>> wrote: Hello All,
I’m using OpenSwan with AWS to link two private VPC networks in
different regions.
I’m having trouble getting my firewall ACLs right. Everything works
if I permit all traffic to the OpenSwan boxes, however when I try to
get more restrictive and permit only the necessary ports things stop
working.
One side has all traffic permitted inbound for the time being and I’m
making ACL changes trying to restrict traffic to certain
ports/protocols on the other side.
Both endpoints are behind 1:1 NAT. Everything is permitted outbound
on both sides.
>From reading online, I understand that the following ports and
protocols should be all I need:
UDP 500
UDP 4500
IP Protocol 50
IP Protocol 51
I tried the above and had no luck. As soon as I change from
permitting all inbound to permitting only the above list the tunnel comes
down.
You should really allow icmp.
Note that you need to accept from a random high port to dest udp 4500,
not just 4500 <-> 4500. Same for 500
I also tried permitting tcp/1721 and tcp/1723 and IP Protocol 47.
I am using AWS ‘security groups’ to control filtering and according to
the docs (and my observations) security groups are stateful, so I am
not sure why this isn’t working.
Can anyone offer any suggestions?
</pre>
</blockquote>
</blockquote>
<pre wrap="">_______________________________________________
<a class="moz-txt-link-abbreviated" href="mailto:Users@lists.openswan.org">Users@lists.openswan.org</a>
<a class="moz-txt-link-freetext" href="https://lists.openswan.org/mailman/listinfo/users">https://lists.openswan.org/mailman/listinfo/users</a>
Micropayments: <a class="moz-txt-link-freetext" href="https://flattr.com/thing/38387/IPsec-for-Linux-made-easy">https://flattr.com/thing/38387/IPsec-for-Linux-made-easy</a>
Building and Integrating Virtual Private Networks with Openswan:
<a class="moz-txt-link-freetext" href="http://www.amazon.com/gp/product/1904811256/104-3099591-2946327?n=283155">http://www.amazon.com/gp/product/1904811256/104-3099591-2946327?n=283155</a>
</pre>
</blockquote>
<br>
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