Programmable router - winapi

I'd like to set up a proxy between my home network and internet.
Currently computers at home connect to a cisco router which is connected to internet.
What I'd like is to set up system so that all internet traffic goes through a proxy - in my case it is a dedicated extra computer (server).
Are there programmable routers that can run some software within the router or using a connected computer?
This way I could use a program to see what goes out and comes in.

If you only want to monitor your network then investigate and learn how to use WireShark. If you want to take the long and much harder route of making a proxy server, use a squid proxy. It runs on a Linux server and you can get a lot of user friendly GUI's. Plus there are hundreds of tutorials.

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How to redirect network traffic to a tcp/udp connection in golang

So I've seen projects like trojan-go,v2ray-go
They are making their own proxy protocols in user space level. I am trying to do the same thing but I don't know how to redirect network traffic from clients to proxy server.
Basically I don't understand how those tools (or any tool) can redirect internet traffic of the device to a certain server, so when the packets are going to the internet they go to the proxy server first instead of their destination ip address.
How can I do it in golang without dealing with netlink and Iptables?
I know apps like wireguard do this by dealing with layer 3-4 stuff using netlink API but I need to know how apps do it without adding a new network interface.

p2p direct data exchange...via HTTPS?

Is there any protocol, API or software in existence that can send data/IM/etc directly from one device to another with no server?
Can you not use HTTP GET/POST/DELETE directly between two devices when their device data is known to the user(s)?
I would very much like to know if there is ANY software/protocols that can do this.
thank you!
The internet is build on the Internet Protocol suite. This suite has 5 different layers of protocols: The physical layer, the link layer, the network layer, the transport layer and the application layer. Each depends on the one before.
If you just use the browser, by default HTTP (application layer) is used, which relies on TCP (transport layer), which relies on IP (v4 or v6, network layer), which relies on ethernet (link layer), which finally relies on the actual cable that's plugged into your computer (for WiFi, the first three are the same but the last two differ if I'm not mistaken).
Now to your question: Is there any protocol, API or software in existence that can send data/IM/etc directly from one device to another with no server?
Yes there is. I suggest you start looking at protocols that are in the application layer. To highlight a few standards next to HTTP(S): FTP is for file transfer, IMAP is for emails clients, SMTP is for email servers and SSH is a secure shell which can also be used to tunnel data through.
For your specific case, I think either FTP (FTPS if you want it over SSL), or SSH can be a solution, but it's hard to know for sure without the specifics.
The only thing that these protocols have in common is that one of the two computers will act like server and the other computer as client. This has as downside that port-forwarding might be necessary.
If you've chosen the protocol you'd like to use, then you're up for the next step, selecting a program that can do that for you. For HTTP(S), I'd recommend Apache. If you're using Linux and chose SSH, then you're in luck, there is a build in SSH server in Linux, you can use that. For other protocols, you might just want to search yourself, as I do not have any suggestions.
I hope this answers most of your questions!
Desirius
In browser context, WebRTC is probably what you are looking for: It allows user to user communications.
https://en.wikipedia.org/wiki/WebRTC
https://webrtc.org/

931107 - configuring squid

i'm too beginner in squid. i want a way to remain anonymous over the net. i also want to be able to access the contents of the internet which are filtered. my Windows computer is beyond firewall (filtered). my server (CentOS 5) is not. for example, when i enter http://facebook.com in the browser url, it redirects to an intranet ip which tells me to avoid going to this site!
now i've installed squid on server and traffic is propagated through this server. but this redirection occurs. so still i can't open filtered sites.
what can i do? a friend of mine told that the only way is to use https. ie. the connection between browser (Firefox) and the server must use this protocol. is it right? and how can i do that?
what's your suggestion? i don't want necessarily to use squid. besides, https protocol gets banned or decreased in speed in my country sometimes. so i prefer the protocol remain http. i thought also about writing a code in client and server to transform, compress/decompress and packetize as hoax binary http packets to be sent as much speed and success as possible. but i'm not an expert in this context and now i prefer more straightforward ways.
i respect any help/info.
I assume you are located in Iran. I would suggest using TOR if you mainly access websites. The latest release works reasonably well in Iran. It also includes an option to obfuscate traffic so it is not easily detectable that you are using TOR.
See also this question: https://tor.stackexchange.com/questions/1639/using-tor-in-iran-for-the-first-time-user-guide
A easy way to get the TOR package is using the autoresponder: https://www.torproject.org/projects/gettor.html
In case the website is blocked, it works as follows:
Users can communicate with GetTor robot by sending messages via email.
Currently, the best known GetTor email address is gettor#torproject.org.
This should be the most current stable GetTor robot as
it is operated by Tor Project.
To ask for Tor Browser a user should send an email to GetTor robot
with one of the following options in the message body:
windows: If the user needs Tor Browser for Windows.
linux: If the user needs Tor Browser for Linux.
osx: If the user needs Tor Browser for Mac OSX.

How to build local web proxy without configuring the browsers

How does Netnanny or k9 Web Protection setup web proxy without configuring the browsers?
How can it be done?
Using WinSock directly, or at the NDIS or hardware driver level, and
then filter at those levels, just like any firewalls soft does. NDIS being the easy way.
Download this ISO image: http://www.microsoft.com/downloads/en/confirmation.aspx?displaylang=en&FamilyID=36a2630f-5d56-43b5-b996-7633f2ec14ff
it has bunch of samples and tools to help you build what you want.
After you mount or burn it on CD and install it go to this folder:
c:\WinDDK\7600.16385.1\src\network\ndis\
I think what you need is a transparent proxy that support WCCP.
Take a look at squid-cache FAQ page
And the Wikipedia entry for WCCP
With that setup you just need to do some firewall configuration and all your web traffic will be handled by the transparent proxy. And no setup will be needed on your browser.
netnanny is not a proxy. It is tied to the host machine and browser (and possibly other applications as well. It then filters all incoming and outgoing "content" from the machine/application.
Essentially Netnanny is a content-control system as against destination-control system (proxy).
Easiest way to divert all traffic to a certain site to some other address is by changing hosts file on local host
You might want to have a look at the explanation here: http://www.fiddlertool.com/fiddler/help/hookup.asp
This is how Fiddler2 achieves inserting a proxy in between most apps and the internet without modifying the apps (although lots of explanation of how-to failing the default setup). This does not answer how NetNanny/K9 etc work though, as noted above they do a little more and may be a little more intrusive.
I believe you search for BrowserHelperObjects. These little gizmos capture ALL browser communication, and as such can either remote ads from the HTML (good gizmo), or redirect every second click to a spam site (bad gizmo), or just capture every URL you type and send it home like all the WebToolBars do.
What you want to do is route all outgoing http(s) requests from your lan through a reverse proxy (like squid). This is the setup for a transparent web proxy.
There are different ways to do this, although I've only ever set it up OpenBSD and Linux; and using Squid as the reverse proxy.
At a high level you have a firewall with rules to send all externally bound http traffic to a local squid server. The Squid server is configured to:
accept all http requests
forward the requests on to the real external hosts
cache the reply
forward the reply back to the requestor on the local lan
You can then add more granular rules in Squid to control access to websites, filter content, etc.
I pretty sure you can also get this functionality in different networking gear. I bet F5 has some products that do some or all of what I described, and probably Cisco as well. There is probably other proxies out there besides Squid that you can use too.
PS. I have no idea if this is how K9 Web Protection or NetNanny works.
Squid could provide an intercept proxy for HTTP and HTTPs ports, without configuring the browsers and it also supports WCCP.

Simulating latency when developing on a local webserver

The Performance Golden Rule from Yahoo's performance best practices is:
80-90% of the end-user response time
is spent downloading all the
components in the page: images,
stylesheets, scripts, Flash, etc.
This means that when I'm developing on my local webserver it's hard to get an accurate idea of what the end user will experience.
How can I simulate latency so that I can understand how my application will perform when I've deployed it on the web?
I develop primarily on Windows, but I would be interested in solutions for other platforms as well.
A laser modem pointed at the mirrors on the moon should give latency that's out of this world.
Fiddler2 can do this very easily. Plus, it does so much more that is useful when doing development.
YSlow might help you out. YSlow analyzes web pages based on Yahoo!'s rules.
Firefox Throttle. This can throttle speed (Windows only).
These are plugins for Firefox.
You can just set up a proxy outside that will tunnel traffic from your web server to it and then back to local browser. It would be quite realistic (of course it depends where you put the proxy).
Otherwise you can find many ways to implement it in software..
Run the web server on a nearby Linux box and configure NetEm to add latency to packets leaving the appropriate interface.
If your web server cannot run under Linux, configure the Linux box as a router between your test client machine and your web server, then use NetEm anyway
While there are many ways to simulate latency, including some very good hardware solutions, one of the easiest for me is to run a TCP proxy in a remote location. The proxy listens and then directs the traffic back to my final destination. On a remote server, I run a unix program called balance. I then point this back to my local server.
If you need to simulate for a just a single server request, a simple way is to simply make the server sleep() for a second before returning.

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