I need a Reverse Proxy to front both Lablz Web server and SSL VPN Adito (SSL Explorer fork) by sitting on one IP/port. Failed to achieve that with Nginx. Failed to use Adito as a generic reverse HTTP proxy.
Can HAProxy fall back to being a TCP proxy if it does not sense HTTP traffic?
In other words can it fall back to Layer 4 if its Layer 7 inspection determines this is not HTTP traffic?
Here is my setup
EC2 machine with one public IP (Elastic IP).
Only one port is open - 443.
Stunnel is sitting on 443 and is passing traffic to HAProxy (I do not like to use Stunnel but HAProxy does not have full support for SSL yet, unlike Nginx).
HAProxy must be configured to pass some HTTP traffic to one server (Apache server which fronts the SVN server) and the rest of the HTTP traffic to our Lablz Web/App server.
All non-HTTP traffic must be forwarded to Adito VPN.
This traffic is:
VNC, NX, SMB
... and all other protocols that Adito supports
I can not rely on source IP address or port to split traffic into HTTP and non-HTTP.
So, can such config be accomplished in HAProxy? Can any other reverse proxy be used for this? Let me know if I am not thinking right about HAProxy and an alternative approach is possible.
BTW, Adito SSL VPN is amazing and if this setup works we will be able to provide Lablz developers with a fantastic one-click single-login secure VNC-over-HTTPS access to their boxes in the cloud.
No solution exists for this but via Adito - please prove me wrong. But please do not say that VNC over SSH is better. Yes, VNC-over-SSH is faster, more secure, but also is much harder (for our target user base) to setup and presumes that user is behind the firewall that allows outbound traffic on port 22 (not always the case).
Besides, Adito is much more than the remote access gateway - it is a full blown in-browser VPN, a software distribution platform and more. I am not associated with Adito guys - see my Adito post on our Lablz blog.
OK, first off, I'd use a simple firewall to divide all HTTP from NON-HTTP traffic. What you need is packet inspection to figure out what it is that is coming in.
Neither haproxy or nginx can do that. They are both made for web traffic and I don't see how they could inspect traffic to guess what it is that they are dealing with.
Update: Looked into this it a bit and with iptables you could probably use string matching to devide the traffic. However, that's all tricky, especially with the encrypted nature. A friend of mine discovered l7-filter and this looks like what you need. Let me know if this helps.
Related
I have drawed the following chart to help explain our situation:
We have an API running on the KESTREL WebServer in the back end. This is running as several instances in docker containers. In front of this, we have a HAProxy Load Balancer which directs the traffic to the Kestrel server with the least connections.
All of this so far is only available internally on our network.
We have one server accessible from the internet, running IIS on port 80 and 443.
In IIS we have added a SSL Certificate which encrypts the communication between the end user and our first entry point.
Is there any further need to encrypt the communication between IIS which proxies the request to our HAProxy on the internal network, and from there on, necessary to encrypt communication from HAProxy to the backends?
As far as my knowledge goes, the only benefit of this, would be that nobody on the internal network at our office can listen to the connections going between the servers, but please correct me if I am wrong here.
I've been wanting to setup a linux VirtualBox instance and use iptables to route traffic from other VMs through it and on to an external SOCKS proxy server. However, I have recently read that transparent proxies like this break HTTPS transmissions and that this is part of the design – to prevent man-in-the-middle attacks. If I want this to work, I'll need to configure the proxy inside the browsers of the VM clients for port 443. Are there any other options I could explore to achieve my goal?
To access a SOCKS server each TCP connection must be prefixed with the necessary SOCKS header. That means, that a simple redirect is not possible. You need instead a protocol converter like redsocks or transocks (never used these, but from the description they do what you need).
Apart from that it is not a problem to simply redirect HTTPS traffic or use these protocol converters, as long as you don't change the SSL stream itself. The only problem is if transparent proxies try to intercept and re-route this traffic to other sites (like redirecting to a capture portal) or try to decrypt the connection in order to analyse it (like in firewalls). These kind of interceptions will be noticed from the browser, because either the name in the certificate does not match the target name and/or the issuer of the certificate is not trusted.
I am looking for a way to forward traffic from an application which goes to the web over port 443 to an instance of Fiddler running on my computer. Fiddler does not see this traffic while a packet trace application verified that the traffic is going out.
The application is foreign and I am not able to modify how it requests and it is not going through Internet Explorer (or apparently any other browser). If this app is going to an ip address (ie. 66.xxx.xx.xx port 443) or to a named host (ie. https://www.anysite.com), is there a way to tell my computer to forward this traffic to Fiddler, ie. to localhost port 8888?
I am not sure I am using the right terminology to describe this but and ideas would be appreciated!
Thanks,
David
If you can't get the application itself to send traffic to localhost on a specified port, then you need something lower level than Fiddler. Try WireShark.
http://www.wireshark.com/
#David: What's the application in question? Virtually all applications can be proxied, because those that can't aren't usable from most corporate networks. In some cases, you have to make minor changes to the environment (e.g. setting the proxy for the JVM). Some details are here: http://www.fiddler2.com/fiddler/help/hookup.asp
Using Netmon or Wireshark, you should be able to determine whether or not the application in question is making a request directly to a fixed IP address, or more likely, doing a DNS lookup first. If it's doing a DNS lookup first, you could edit your Windows Hosts file so that whateverthehostis.com points at 127.0.0.1. Because the hosts file only maps host to IP and not port to port, you'll need to adjust Fiddler to run on the target port that the application is looking for (use Tools > Fiddler Options for that).
Now, if the traffic is HTTPS (and I'm guessing it is) you're going to have a problem at that point, because Fiddler currently can only act as a HTTPS endpoint when it "knows" that the traffic is HTTPS by virtue of the client having opened a CONNECT tunnel first. This is something that could be adjusted in a future version of Fiddler, but it's not a common request.
So I've gone ahead and set up my ShoutCast server DNAS and set my DSP in Winamp on my host computer. The server listens on port 8000, so per some instructions I installed an output plugin for winamp (Shoutcast DSP) and used 8000 and the password to connect. Server accepts the connection.
Now, what the heck do I do now? My host computer is SSL secured and the DNAS server is installed within the secure web directory (if that matters). My desired end result is that I want to listen to my ShoutCast setup at home (host computer) from any computer.
I try browsing to my ip address and port 8000 (without using HTTPS) and it comes back with nothing. If I browse with HTTPS://my.server.com:8000, I get Error code: ssl_error_rx_record_too_long)
Have I completely missed something, or am I just a total moron?
Thanks.
SHOUTcast doesn't support SSL. The service on port 8000 is an unencrypted server for HTTP and ICY (the rather pointless SHOUTcast native streaming protocol, which is almost but not quite HTTP). The ssl_error_rx_record_too_long error is characteristic of trying to access a non-HTTPS service as HTTPS.
You should be able to connect to 8000 with your web browser and get the DNAS status page. If, on the other hand, you connect to that port with a media player, it'll return the direct MP3 stream. (Unfortunately, in an incredibly boneheaded piece of design, the way SHOUTcast decides which to respond with is by sniffing your User-Agent header for something beginning with Mozilla, so if you're using an alternative browser or blocking your UA you'll not be able to get the status, and if the stream's down you might just get nothing.)
To listen to a SHOUTcast server through SSL you would need to set up a proxy on another port that forwarded HTTPS requests to local HTTP requests; it'd also have to be a streaming-capable proxy, and you might need some hacks to stop ICY breaking it.
Probably easier, you could set up an SSH forwarded port from your client to the server. That would also be the only way to allow the DJ to connect to SHOUTcast with encryption, since the DJ protocol isn't HTTP compatible at all. Obviously SSH tunnels are no good for random public listeners though.
You could also try Icecast, an alternative to SHOUTcast that I believe has some SSL support (and also uses plain HTTP streaming instead of ICY).
I've got a local application (which I didn't write, and can't change) that talks to a remote web service. It uses HTTPS, and I'd like to see what's in the traffic.
Is there any way I can do this? I'd prefer a Windows system, but I'm happy to set up a proxy on Linux if this makes things easier.
What I'm considering:
Redirecting the web site by hacking my hosts file (or setting up alternate DNS).
Installing an HTTPS server on that site, with a self-signed (but trusted) certificate.
Apparently, WireShark can see what's in HTTPS if you feed it the private key. I've never tried this.
Somehow, proxy this traffic to the real server (i.e. it's a full-blown man-in-the-middle "attack").
Does this sound sensible? Can WireShark really see what's in HTTPS traffic? Can anyone point me at a suitable proxy (and configuration for same)?
Does Fiddler do what you want?
What is Fiddler?
Fiddler is a Web Debugging Proxy which
logs all HTTP(S) traffic between your
computer and the Internet. Fiddler
allows you to inspect all HTTP(S)
traffic, set breakpoints, and "fiddle"
with incoming or outgoing data.
Fiddler includes a powerful
event-based scripting subsystem, and
can be extended using any .NET
language.
Fiddler is freeware and can debug
traffic from virtually any
application, including Internet
Explorer, Mozilla Firefox, Opera, and
thousands more.
Wireshark can definitely display TLS/SSL encrypted streams as plaintext. However, you will definitely need the private key of the server to do so. The private key must be added to Wireshark as an SSL option under preferences. Note that this only works if you can follow the SSL stream from the start. It will not work if an SSL connection is reused.
For Internet Explorer this (SSL session reuse) can be avoided by clearing the SSL state using the Internet Options dialog. Other environments may require restarting a browser or even rebooting a system (to avoid SSL session reuse).
The other key constraint is that an RSA cipher must be used. Wireshark can not decode TLS/SSL stream that use DFH (Diffie-Hellman).
Assuming you can satisfy the constraints above, the "Follow SSL Stream" right-click command works rather well.
You need to setup a proxy for your local application and if it doesnt honour proxy settings, put a transparent proxy and route all https traffic into it before going outside. Something like this can be the "man" in the middle: http://crypto.stanford.edu/ssl-mitm
Also, here's brief instructions on how to archive this with wireshark: http://predev.wikidot.com/decrypt-ssl-traffic
You should also consider Charles. From the product description at the time of this answer:
Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet. This includes requests, responses and the HTTP headers (which contain the cookies and caching information).
For using https proxy to monitor, it depends on the type of handshake. If you local application does not check the server's certificate by CA's signature which you can not fake, and the server does not check your local application's certificate ( or if you have one to setup on https proxy) then you can set up a https proxy to monitor the https traffic. Otherwise, I think it is impossible to monitor traffic with https proxy.
Another way you can try is to add instrumentation probe at the routines of your client program where it send and receive messages from its https library. It needs some reverse engineering work, but should work for you for all situations.
I would recommend WireShark, it is the best tool to follow on different pieces of traffic. Although, I am not sure what can you see with SSL turned on. Maybe, if you supply it with a certificate?