I am making a proxy for Windows. I would like to be able to block certain documents under specific URLs.
For example, everything on google.com would work fine, but google.com/index.html could be blocked.
Can anyone help with this please?
I want the proxy to run on the same PC that uses it.
I have found what I needed. Sorry if I wasn't specific enough.
For any future users who come across this post and know what they are after - try FiddlerCore for .NET applications. It's a great package enabling you to capture and 'fiddle' with HTTP and HTTPS responses before they reach your device.
This means that FiddlerCore can be used to analyse a request's header, check for a certain URL and then drop the request.
There are two methods:
(1) using FiddlerCore package
(2) modification of "hosts" file
1)
FiddlerCore is a .NET package which is used to analyse packets in the network.
A deep knowledge in FiddlerCore is required because it contains dangerous functions as well as most helpful functions.
2)
You can block websites by appending curresponding URL to the "hosts" file.
Navigate to C:\Windows\System32\drivers\etc, changing C: to whatever drive letter you have Windows installed on. Select "hosts" to open it.
Just append in a new line :
127.0.0.1
You want to get Administrative privilege for your application to modify the hosts file.
Related
So I got it to the stage where the .net (framework) console application could run on localhost, but the next issue is exposing it using Nginx.
I looked at many tutorials, but they all seems to be for websites. How can i make it work for a console app?
Thank you.
What do you gain from using nginx in front of it instead of just
opening the console app on port 80 (or preferably 443 witha
certificate)? You will probably need to set up nginx as a reverse
proxy for your app.
I have the console app running on port 1234 because there is already an app using port 80. To be honest, I am not sure why I am using Nginx, I just assume that's what I need, since I have the app running on localhost but I cannot access it from outside. I have set the firewall to accept that port from the domain provider side.
uhm.... what exactly do you mean by "exposing a console application"?
because what you expose with nginx - or any other webserver - is a
website. also: welcome to stackoverflow. i recommend taking the tour,
as well as reading how to ask a good question and what's on topic.
Thank you. I am probably not using the most accurate term. Basically, I just want people to be able to access my app. In my mind, I imaging there is some additional setting I need to do to have it "exposed" to the public (and that's using nginx). I can see the app running on localhost but not sure why it's not public.
please say what you expect a console app 'exposed to the public' would
look like. How would they access it? What tool on my desktop would I
start, ignore the nginx part of the discussion
So I have a loop serving some web content similar to this one.
https://gist.github.com/define-private-public/d05bc52dd0bed1c4699d49e2737e80e7
When I run it, external user should go to a website and see the page content served up by this.
If your console app is a Console.ReadLine() Console.WriteLine() type
thing the only way to expose it simply is to setup and SSH server on
your host system. Then the users need an SSH client to access it. This
is doable via web browser hosted SSH access but thats v complex
solution
You can ignore all the Console Readline and Writeline stuff.
Ok, so the solution is actually quite simple. All you need to do is forward your incoming request to a localhost using proxy_pass, as suggested by #fredrik. The following should be added to the default config file (under nginx):
server {
listen 80;
listen [::]:80;
server_name example.com;
location / {
proxy_pass http://localhost:8888/;
}
}
It is not a specific problem because I have more than one experience that fiddler save my app.
A recent example:
I had an excel addin app write in C#. In the app I had a httpclient to connect to my server through ssl. And I ignored the certification in my code explicitly.
The app always worked well(I mean the connection part), but one day in a QA environment, it failed in no causes. The connection seemed to be blocked for long long time.
Coincidentally, we opened the Fiddler and tried to grab some http. Then everything worked fine.
(Fiddler may do something in the middle)
Then after closing Fiddler, we cannot recreate the problem because all things went back to fine again.
(Fiddler change something permanently!)
Here are some clues:
We use the normal C# http clients System.Net.Http .
Our server is ssl (https, but we must ignore the cert)
The app was good in the same environment at frist.
The lastest change is about the localization, and the test enviroment changed the windows local and language.
We are under a company network, using a proxy in the example above.
The failure is not the whole connection module, but a specific request.(In our case, a request that post two small xml files including excel itself)
Please give us some hint and guess, so we can feel better on this mystical problem.
How long is a "long long time" exactly?
Fiddler does not make any persistent changes to the system; if you start and stop it, the system is returned to the prior configuration. I suppose it's remotely possible that if some configuration setting were corrupt before Fiddler ran, that corruption wouldn't be replicated after Fiddler attempted to reapply it, but we don't know of any such "corrections."
This article describes some of the things folks find unexpected in terms of Fiddler "magically" fixing things while it runs.
I want to run an exe on client system from my c# asp.net website. When I use Process.Start()
it throws an error:
The requested operation requires elevation.
How do I set permissions to run that exe?
You can't spawn processes on the client machine from server-side code.
When you use Process.Start in server-side code, it is attempting to execute the process there, on the server where the website is hosted. If you wanted to create processes on the clients computer then you would need to expose a download for them (and not in employing subterfuge, like malign sites might do to install software - supply it gracefully, and normally (and with permission)), or a Silverlight application or something along those lines.
The bottom line is that the code you want to execute (even if that is just to spawn a process) must reside on the client, and be executed there.
You can't run an application from a web server like that. You will have to have the user download the application by supplying the EXE, a setup file or using ClickOnce.
Or you can develop an ActiveX control that you can have the browser automatically download from a Trusted Internet Zone.
Once downloaded, proper signing with a certificate (signed from the trusted (corporate) root certificate) will avoid the user getting a prompt to ask whether he wishes to allow the ActiveX control to install/be activated -
The ActiveX control can subsequently do anything the interactively logged on user could. This means that to actually install a program you'd need to elevate (UAC on Vista+); But if the goal was just to run a standalone executable, you should be good to go.
This all assumes white-hat purposes in a (larger) corporate setting, because it relies on PKI infrastructure and central browser policies, to name just two.**
This would, really, lead to some excellent questions on serverfault or superuser
I noticed you said you wanted to run an exe file on the client, but you didn't say explicitly that the exe is on the server and you want to push it to the client. Everyone seems to be assuming that is the case.
You CAN accomplish this fairly easily with a small JavaScript if you have a few prerequisites:
The executable is already present on the client machine.
All of your clients are running IE
You can enforce a policy to put your site in the Intranet or Trusted
Sites zone.
So basically this means it's a corporate intranet application. I am assuming this is probably the case since, well, if you were expecting to do this with a public app, I would be surprised.
For the script to accomplish this, please see my answer to this question:
How can I get a program on a client machine to run from an ASP.NET page?
I have a bug where special characters (danish 'ø' in this case) are shown correctly when running locally, but wrong when the code runs on a server (I get a pipe '|'). I was trying to solve this today, but I did not have access to the server, other than updating the code files. I will limited access monday, so I can at least write intermediate results to a log file, but to be prepared I thought I'd ask for suggestions here.
Program flow:
A C# test calls my own web service via a WebRequest.
This web service calls an external web service via another web request.
When running my own web service locally I get correct results returned from the external web service.
When deploying the code to the server the external web service returns an error; it didn't find the word I was searching for. Except that I entered 'Bøssemagergade', but the word it complains about is returned as 'B|ssemagergade'. What can cause this difference? AFAIK the server runs with the exact same regional settings as my local machine.
I'm sure this is common stuff, but I haven't been doing web services before (I do feel at home with C#/.NET though, and know about encodings etc.).
Thanks!
You need to check your data at every stage in the process. Make sure you understand which encoding you're using (try to avoid using Encoding.Default) and verify the binary data going across the wire with something like WireShark.
See my debugging unicode problems article for further information.
I need a way to programaticaly block and then later unblock specific websites based on their domain names. I only need to block browsers (so http & https would be sufficient, I guess?) but not just Internet Explorer, it should also work for anyone trying to run Chrome or Firefox too.
This needs to work on Windows XP and be usable from a .NET program (Vb.net or C#).
(ps., I had found this question: How to unblock website which is blocked, using C#? which seems to be saying the same thing, however at the time I could not understand it. Now I see it, thanks all.)
Thanks,
This line in the hosts file will redirect to localhost. Though I have nothing against Nascar ;)
127.0.0.1 www.nascar.com
Block websites using a hosts file.
A down and dirty way would be to dynamically update the hosts file.
c:\Windows\System32\drivers\etc\hosts
You could add entries to the Hosts.ini file to achieve this. It would only work on Windows. Have a look here link text
First off, know that you need to be an Administrator to do this stuff.
Well, you can just add a line to the hosts file in ( c:\Windows\System32\drivers\etc\hosts ) with the site you want, such as:
127.0.0.1 www.example.com
After that is done, just run the following command:
ipconfig /flushdns
Some web browsers, including Firefox, will also have to be restarted as well.
To unblock a blocked site, just delete it's entry from the hosts file, or place a # sign at the beginning of it.