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64-bit Cisco VPN client (IPsec)?

Cisco VPN client (IPsec) does not support 64bit Windows.

Worse, Cisco does not even plan to release a 64-bit version, instead they say that
"For x64 (64-bit) Windows support, you must utilize Cisco's next-generation Cisco AnyConnect VPN Client."

But SSL VPN licences cost extra. For example, most new ASA firewalls come with plenty of IPSec VPN licences but only a few SSL VPN licences.

What alternatives do you have for 64-bit Windows? So far, I know two:

  1. 32-bit Cisco VPN Client on a virtual machine
  2. NCP Secure Entry Client on 64-bit Windows

Any other suggestions or experiences?


Source: (StackOverflow)

OpenVPN low performance. Do I have MTU problems? Dumps inside

I have problems with an OpenVPN tunnel which does not reach line speed. The gateway is a Debian Jessy virtual server hosted at OVH. The client is either my freebsd 10.2 homeserver (Intel I3 Ivy Bridge) or my RaspberryPI2. I deactivated encryption and authentication. I have a 100mbit/s symmetrical FTTH connection but the tunnel only reaches a speed of 20-40mbit/s. Direct connection (without tunnel) always yields the 100mbit/s I expect. I tested the performance with iperf3. I first tried with my freebsd homeserver. I tried all the recommended settings about mssfix, fragment etc. Nothing helped.

Then I thought maybe it is my freebsd machine. So I installed a fresh raspbian Jessy on my RPI2 and did some more in depth testing:

First of all I removed all the MTU settings from the OpenVPN configs and let the path MTU handle things (hopefully). Since I have no firewall active on both machines it should work. These are my vpn configs:

server 10.8.0.0 255.255.255.0
port 1194
proto udp
dev tun
sndbuf 0
rcvbuf 0

user nobody
group nogroup
persist-key
persist-tun
ifconfig-pool-persist ipp.txt
keepalive 10 120
push "redirect-gateway def1"
status openvpn-status.log
verb 3

ca /etc/openvpn/easy-rsa/keys/ca.crt
cert /etc/openvpn/easy-rsa/keys/vpn.theissen.io.crt
key /etc/openvpn/easy-rsa/keys/vpn.theissen.io.key
dh /etc/openvpn/easy-rsa/keys/dh4096.pem
tls-auth /etc/openvpn/easy-rsa/keys/ta.key 0
cipher none
auth none
comp-lzo no



client
proto udp
dev tun12
remote xxx.io 1194
resolv-retry infinite
sndbuf 0
rcvbuf 0

nobind
user nobody
group nogroup
persist-key
persist-tun
verb 3

pkcs12 /etc/openvpn/vpn.theissen.io/alex.p12
tls-auth /etc/openvpn/vpn.theissen.io/ta.key 1
ns-cert-type server
cipher none
auth none
comp-lzo no

First of all the test without the tunnel to show that the connection to the server is indeed almost 100mbit/s:

iperf3 -c vpn.theissen.io
Connecting to host vpn.theissen.io, port 5201
[  4] local 192.168.1.253 port 34512 connected to 149.202.58.183 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  10.8 MBytes  90.5 Mbits/sec    0    335 KBytes       
[  4]   1.00-2.00   sec  11.4 MBytes  95.7 Mbits/sec    0    335 KBytes       
[  4]   2.00-3.00   sec  11.1 MBytes  93.0 Mbits/sec    0    352 KBytes       
[  4]   3.00-4.00   sec  11.2 MBytes  94.0 Mbits/sec    0    369 KBytes       
[  4]   4.00-5.00   sec  11.5 MBytes  95.9 Mbits/sec    0    390 KBytes       
[  4]   5.00-6.00   sec  11.0 MBytes  92.5 Mbits/sec    0    390 KBytes       
[  4]   6.00-7.00   sec  11.4 MBytes  95.2 Mbits/sec    0    390 KBytes       
[  4]   7.00-8.00   sec  11.2 MBytes  94.3 Mbits/sec    0    390 KBytes       
[  4]   8.00-9.00   sec  11.1 MBytes  93.3 Mbits/sec    0    390 KBytes       
[  4]   9.00-10.00  sec  11.3 MBytes  95.1 Mbits/sec    0    390 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec   112 MBytes  93.9 Mbits/sec    0             sender
[  4]   0.00-10.00  sec   112 MBytes  93.5 Mbits/sec                  receiver

iperf Done.

The packets of this connection I dumped with tcpdump on the server. You can download them here (you have to extract to open them with wireshark): dumpraw.cap.xz

So this is how a "OK" dump looks like. Maximum frame size I spotted is 1514. Dump of iperf3 without tunnel

Now I ran the test over the tunnel:

iperf3 -c 10.8.0.1
Connecting to host 10.8.0.1, port 5201
[  4] local 10.8.0.14 port 36388 connected to 10.8.0.1 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  5.96 MBytes  50.0 Mbits/sec  127    133 KBytes       
[  4]   1.00-2.00   sec  5.19 MBytes  43.5 Mbits/sec    6    120 KBytes       
[  4]   2.00-3.00   sec  5.80 MBytes  48.7 Mbits/sec    0    151 KBytes       
[  4]   3.00-4.00   sec  4.27 MBytes  35.9 Mbits/sec   23   96.5 KBytes       
[  4]   4.00-5.00   sec  4.89 MBytes  41.0 Mbits/sec    0    129 KBytes       
[  4]   5.00-6.00   sec  6.11 MBytes  51.2 Mbits/sec   26    111 KBytes       
[  4]   6.00-7.00   sec  5.50 MBytes  46.1 Mbits/sec    0    143 KBytes       
[  4]   7.00-8.00   sec  5.25 MBytes  44.1 Mbits/sec   15    126 KBytes       
[  4]   8.00-9.00   sec  5.80 MBytes  48.7 Mbits/sec    0    158 KBytes       
[  4]   9.00-10.00  sec  3.97 MBytes  33.3 Mbits/sec   22    105 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec  52.7 MBytes  44.2 Mbits/sec  219             sender
[  4]   0.00-10.00  sec  52.3 MBytes  43.8 Mbits/sec                  receiver

iperf Done.

Whoops. Not so nice anymore. Especially this "Retr" column does not look so good. I assumed this is the tcp retransmit and there should be then something in the dump. We will see that it is not the case :/. CPU is not the bottleneck here because I deactivated enrcyption and authentication. CPU is at 20% at the server and 50% on the PI during the test.

This is how the OpenVPN traffic of the test looks like: OpenVPN traffic on physical interface

To me this looks okay. But I do not know what to look for. Please have a look at the dump with wireshark: dump_physical.cap.xz

The traffic on the tunnel interface looks good to me, too. It seems that he correctly lowered the frame size (to 1444 as it seems): iperf3 traffic on the tunnel interface

Here is the dump: dump_tunnel.cap.xz

To me this looks all fine but I really have no idea what to look for exactly. I really tested everything out with the OpenVPN settings. Maybe someone can tell me if the traffic looks okay.

What I expect as an answer

At least an explanation what is happening here and why it seems to be independent of the VPN software I use. Everything what I found on the internet was about MTU problems but that should be easily fixed by reducing the tunnel MTU or the other parameters of OpenVPN. For me this changes little. When you look at the dump you see that it reduces the tcp segment size and packets are not fragmented. There must be something else. I really like to know what.

Update

I tested this with strongswan and even with softether. It's actually the same problem (comparable speed, no cpu bottleneck). I am really puzzled what is the problem here. I also tried another gateway (RaspberryPi2 on friends 100/100 home connection).

Update 2

I noticed that iperf3 reports tcp retransmits (retr) but there are no retransmits in the dump (Wireshark should highlight them). What is going on?

I even tried OpenVPN on my local Network (RaspberryPi2 to FreebsdServer). Even there I have a lot of retransmits (on LAN?!):

Connecting to host 192.168.222.11, port 5201
[  4] local 192.168.222.10 port 46196 connected to 192.168.222.11 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  9.19 MBytes  77.0 Mbits/sec    8    141 KBytes       
[  4]   1.00-2.00   sec  8.71 MBytes  73.1 Mbits/sec    3    130 KBytes       
[  4]   2.00-3.00   sec  8.59 MBytes  72.0 Mbits/sec    3    120 KBytes       
[  4]   3.00-4.00   sec  8.65 MBytes  72.5 Mbits/sec    4    108 KBytes       
[  4]   4.00-5.00   sec  8.65 MBytes  72.5 Mbits/sec    4   95.6 KBytes       
[  4]   5.00-6.00   sec  8.52 MBytes  71.5 Mbits/sec    2   80.5 KBytes       
[  4]   6.00-7.00   sec  8.83 MBytes  74.1 Mbits/sec    0    141 KBytes       
[  4]   7.00-8.00   sec  8.59 MBytes  72.0 Mbits/sec    7    106 KBytes       
[  4]   8.00-9.00   sec  8.71 MBytes  73.1 Mbits/sec    3   94.2 KBytes       
[  4]   9.00-10.00  sec  8.59 MBytes  72.0 Mbits/sec    3   79.2 KBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  4]   0.00-10.00  sec  87.0 MBytes  73.0 Mbits/sec   37             sender
[  4]   0.00-10.00  sec  86.8 MBytes  72.8 Mbits/sec                  receiver

In reverse mode I have a really weird congestion window (wtf?):

Accepted connection from 192.168.222.10, port 46197
[  5] local 192.168.222.11 port 5201 connected to 192.168.222.10 port 46198
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  5]   0.00-1.00   sec  8.90 MBytes  74.7 Mbits/sec    3   1.48 GBytes       
[  5]   1.00-2.00   sec  8.45 MBytes  70.9 Mbits/sec    2   1.59 GBytes       
[  5]   2.00-3.00   sec  8.66 MBytes  72.7 Mbits/sec  518    214 MBytes       
[  5]   3.00-4.00   sec  7.96 MBytes  66.8 Mbits/sec   37    703 MBytes       
[  5]   4.00-5.00   sec  8.09 MBytes  67.9 Mbits/sec    0    719 MBytes       
[  5]   5.00-6.00   sec  8.04 MBytes  67.5 Mbits/sec    0    734 MBytes       
[  5]   6.00-7.00   sec  8.07 MBytes  67.7 Mbits/sec    1    703 MBytes       
[  5]   7.00-8.00   sec  8.07 MBytes  67.7 Mbits/sec    1    703 MBytes       
[  5]   8.00-9.00   sec  7.99 MBytes  67.1 Mbits/sec    2    693 MBytes       
[  5]   9.00-10.00  sec  8.06 MBytes  67.6 Mbits/sec    1    693 MBytes       
[  5]  10.00-10.09  sec   684 KBytes  64.5 Mbits/sec    0    695 MBytes       
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Retr
[  5]   0.00-10.09  sec  83.0 MBytes  69.0 Mbits/sec  565             sender
[  5]   0.00-10.09  sec  0.00 Bytes  0.00 bits/sec                  receiver

Update 3

Using iperf with udp results in ovh temporary blocking that port (they send me an email informing me about an attack) and massive packet loss:

-----------------------------------------------------------
Server listening on 1194
-----------------------------------------------------------
Accepted connection from 185.22.143.160, port 15906
[  5] local 149.202.58.183 port 1194 connected to 185.22.143.160 port 4355
[ ID] Interval           Transfer     Bandwidth       Jitter    Lost/Total Datagrams
[  5]   0.00-1.00   sec  2.89 MBytes  24.2 Mbits/sec  0.727 ms  1017/1387 (73%)  
iperf3: OUT OF ORDER - incoming packet = 1409 and received packet = 1470 AND SP = 5
iperf3: OUT OF ORDER - incoming packet = 1410 and received packet = 1471 AND SP = 5
iperf3: OUT OF ORDER - incoming packet = 1411 and received packet = 1472 AND SP = 5
iperf3: OUT OF ORDER - incoming packet = 1445 and received packet = 1473 AND SP = 5
iperf3: OUT OF ORDER - incoming packet = 1463 and received packet = 1473 AND SP = 5
[  5]   1.00-2.00   sec  3.29 MBytes  27.6 Mbits/sec  0.716 ms  1110/1526 (73%)  
[  5]   2.00-3.00   sec  3.30 MBytes  27.7 Mbits/sec  0.732 ms  1103/1526 (72%)  
[  5]   3.00-4.00   sec  3.27 MBytes  27.4 Mbits/sec  0.717 ms  1108/1526 (73%)  
[  5]   4.00-5.00   sec  1.56 MBytes  13.1 Mbits/sec  0.837 ms  546/746 (73%)  
[  5]   5.00-6.00   sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
[  5]   6.00-7.00   sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
[  5]   7.00-8.00   sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
[  5]   8.00-9.00   sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
[  5]   9.00-10.00  sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
[  5]  10.00-10.06  sec  0.00 Bytes  0.00 bits/sec  0.837 ms  0/0 (-nan%)  
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Jitter    Lost/Total Datagrams
[  5]   0.00-10.06  sec   118 MBytes  98.5 Mbits/sec  0.837 ms  4884/6711 (73%)  
[SUM]  0.0-10.1 sec  4884 datagrams received out-of-order

Source: (StackOverflow)

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telnet counterpart for UDP

Is there anything that enables a "telnet-like" functionality for UDP? I know the difference between TCP and UDP, and why telnet itself won't work - but I'm wondering if there is something similar to the telnet client, from the end-user perspective. E.g. udp-telnet [ip] [sending-port] [receiving-port] which then prints out wether a packet made it back or not.

Having a tool like this would proove helpful for testing out firewall settings for OpenVPN which uses UDP connections.


Source: (StackOverflow)

Basic firewall, switch, & router device? [closed]

I am a developer and haven't dealt with server admin or networking in years, so "rusty" is very generous. I am setting up a new web server cluster (starting with two 1U web servers and one DB server). As I haven't done this in a few years, I don't really know what options are available today.

I would like all in one device:

  • Small, basic gbit switch
  • Small, basic firewall
  • Small, basic router/DHCP/gateway
  • Small, basic VPN access
  • Fits in a 1U space

Something simple with a minimal web interface I can set up and then forget about - 2 steps above a home router device, I suppose.

Edit: the initial reaction from sysadmins is often "no way" because to them, devices that do all this are usually crap. Please realize for my purposes, that's currently OK. My setup (and budget) are just not big enough to justify dedicated equipment that does this stuff really well. I just need something that does this stuff at all.

Recommendations?


Source: (StackOverflow)

How to get forticlient working in OSX El Capitan

The forticlient VPN software is borked, when using split horizon, since OSX El Capitan. The problem is that DNS requests are sent out on the normal primary interface to the DNS of the VPN tunnel.

How do we get the DNS requests to be sent out over the correct interface (i.e. VPN tunnel)


Source: (StackOverflow)

Free SSL VPN client

What is the best free SSL VPN client that works on 64 and 32 bit windows clients?


Source: (StackOverflow)

Linux solution for VPN on-demand for iOS devices

According to Apple’s support article on VPN for iOS, only Cisco IPSec, Juniper Junos Pulse, and Cisco AnyConnect support the VPN on-demand feature. Are there any open-source implementation (‘free’ as in beer is more important here) of these that I could deploy on a Linux-based system with no special hardware?

Update: I already have a PPTP solution. I am specifically interested in the on-demand features of the other two.


Source: (StackOverflow)

Security of PPTP vs IPSec

Is PPTP or IPSEC VPN more secure than the other for 'dial in' VPN, if so, why?


Source: (StackOverflow)

What's the protocol-level difference between IPSec and "Cisco IPSec"?

Most VPN clients distinguish between IPSec and "Cisco IPSec." For example, (Apple's) iOS treats them as essentially separate things.

But I can't find any explanation of what the protocol-level differences are. They may be minor, but there definitely appear to be differences.

Can someone shed light on this? Even just a pointer to a detailed explanation would help a great deal. Thanks!


Source: (StackOverflow)

Can you recommend a good intro to iptables? [closed]

I have to setup a firewall on a Linux server (all my previous experience is with Windows). My rules are meant to be pretty simple - forbid all, allow some ports with all, allow some ports for specific IP subnets, while the network is small but complex (each host has IPs in at least 2 192.168... nets, everyone can interconnect many different ways). I think using iptables wrappers can overcomplicate the system logically introducing many unnecessary entities and it would be better to keep it simple and use iptables directly.

Can you recommend a good quick intro on how to write iptables rules?


Source: (StackOverflow)

Windows SSH Tunnel Manager

What application do you use on windows to create SSH tunnels

On Linux I use gSTM, and on OSX I have used STM, but I am not able to find any similar free tools on windows.

I don't want to use putty, or plink for these tunnels, because, I am looking for something that will sit in the tray starting stopping tunnels can easily be done by right-clicking. Ideally the configuration will be stored in a text file or something so I can automate the install of the app, keys, and tunnel configuration on a computer using a script.

Free is proffered, but please post information about any good windows SSH tunnel manager.


Source: (StackOverflow)

How to resolve a "driver failure" error in the Cisco VPN client connecting from a Windows 7 client

I have recently upgraded my laptop from Windows Vista SP1 to Windows 7 Professional.

After the upgrade, if I try to use the Cisco VPN client to connect to a network, I get this message:

Secure VPN Connection terminated locally by the Client.
Reason 440: Driver Failure.

Prior to the upgrade, I was able to connect with no problems.

The version of the client I am using is 5.0.05.0290.


Source: (StackOverflow)

OpenVPN and DNS. How to?

I'm using OpenVPN to set up a VPN to connect my laptop at home to my workplace LAN. I want to be able to refer my workplace computers by their name and not by their IP but I can't.

This is my situation:

Workplace LAN:

  • Address space: 192.168.101.0/24
  • Router address: 192.168.101.1

Home LAN:

  • Address space: 192.168.1.0/24
  • Router address: 192.168.1.1

VPN:

  • Address space: 10.100.1.0/24
  • OpenVPN server address: 10.100.1.1

All machines are running Microsoft Windows.

At my workplace, the PC running as the OpenVPN server is 192.168.101.50 (and 10.100.1.1 in the VPN), and its machine name is workplaceserver.

At my workplace the name workplaceserver is resolved to address 192.168.101.50, but in the vpn client the name workplaceserver can't be resolved, I want it to be resolved to 10.100.1.1. How should I configure OpenVPN in order to achieve that?


Source: (StackOverflow)

What is TLS and how does it compare to SSL?

Is TLS the "new" version of SSL? What features does it add, or security issues does it address?

Can anything that supports SSL support TLS? What would be involved in making the switch? Is the switch worth it?

Why is it that emails are sent over "Opportunistic TLS" and VPN's often called SSL VPN? Is there a difference in the technology, perhaps creating room for a "TLS VPN" product line ?


Source: (StackOverflow)

Is the Windows VPN secure?

I have used a few VPN solutions over the years. Most are hard to set up, slow to connect and/or rather ill-behaved (replacing system drivers, disrupting each other etc).

One solution I have never used earlier is the one built into Windows. This is mostly because the infrastructure guys always refuse to use it because they claim it's 'not secure'.

Now I have finally had the chance to use it (on Windows 7), and wow, it's a breeze! Easy to set up, well-behaved, it connects almost instantly, automatically authenticates with my logged-in credentials, and integrates excellently with the UI. I have to say, unless it really isn't secure, I'll be happy if I never have to use another VPN product ever again.

I gather the Windows VPN used to rely on PPTP, which is not considered secure. But in Windows 7/2008, it supports L2TP/IPSec, SSTP and IKEv2, and authenticates with EAP or CHAP/CHAPv2. That seems pretty up-to-date to me.

But I'm just a lowly developer. Can someone in the know give me the lowdown on this?


Source: (StackOverflow)