Bypass proxy when calling a web service from a Windows service - vb.net

I have a Windows service that is calling a web service, passing a string, and returning a success or error message.
Everything has worked fine in all my testing and development... until I tried to roll it out internally on a network with a proxy server. The web service addresses are not internal but they need to bypass the proxy server to work correctly. If I disconnect my machine from our network and access the internet directly it works fine and the web service is accessible, but if I am connected to the corporate network it fails.
I can add a service reference fine because that uses the proxy settings for my user and this address is set to bypass the proxy. I have tried to run the service with my user credentials and it still doesn't work.
This is what I am using to call the web service:
Dim results As String
Dim objJob As CheckValidationKey.ImportProjectInfo = New CheckValidationKey.ImportProjectInfo
objJob.Credentials = System.Net.CredentialCache.DefaultCredentials
results = objJob.CheckValidationKey(ValidationKey)
What I can't seem to figure out is how to bypass the proxy. I have tried options in the app.config without any luck.

I didn't get an answer and would still like one, however, this specific issue is no longer a problem. It turns out that the proxy wasn't even the problem, but rather that the specific network segment I was trying to use had soap requests blocked. All those hours!

Related

Vue.js + Net Core 3.1 - Redirect API calls

I'm having an issue with a project I'm working on. I have a Vue client which does API calls to my backend which is written in .NET Core 3.1. Both these applications are deployed on diffent servers.
Now the problem is that my backend server does not allow me to do API calls straight from the browser. So I have to do some kind of 'redirect' on the client server to reach my API.
So for example:
If I call backend_server/api/values I get an error (Firewall).
I think I should make like a second API or something, but I'm not sure how to handle this issue.
Does anybody have any experience on this? Any help is welcome!
Kind regards
You can have multiple options here
Remove the firewall rule -
This will allow your API to get hit from browser. If firewall is not managed by you you can't do this
Add IP or Port exception rule in firewall -
Instead of deactivating the entire inbound rule on server, you can allow specific ports or IP on firewall. Again if you have control on firewall
Create Proxy API -
Another way is you can create a middleware API that forwards your request and acts as a proxy. This will suffice performance, resource, time and compromise security. I recommend not to do this, But it's easily possible in .NET Core
Specify CORS policy -
If your Vue.js and API originates from same origin (IP), You can configure CORS in server which will restrict access to API only from same origin. That means only www.google.com can access GoogleAPI, Likewise. This will protect the API from other origins
Tunnel via VPN -
If security is a concern, Use a VPN service to tunnel your API requests. This can't be possible for every client using your web service.
The best way is to open a specific rule on server for your application if possible. Writing a proxy in between will have lot of disadvantages although can be accomplished.

IIS Reverse Proxy ARR with certificate authentication

I have a scenario where I want to consume a Webservice from a different server within our corporate network using JQuery. My origin application is an ASP.NET Website running on IIS 7.5, the Webservice is running on an SAP Netweaver Gateway, so no Chance to allow my IIS host there or to use JSONP.
The problem is that I run into the CORS issue, so I installed ARR on my IIS machine and tried to do a rewrite url and use my IIS to consume the remote Webservice. But the problem is, that the target Webservice requires Certificate authentication and it seems that this is not supported by ARR. Am I correct?
Any help is appreciated,
Oliver
I have had a similar issue, in my first try I had both my application and ARR running on the same box and this was causing the Application's Authentication module to start first before ARR and was messing up the things, I found success when I had both of them run on different boxes. Below link helped me
http://blogs.msdn.com/b/asiatech/archive/2014/01/28/configuring-arr-with-client-certificate.aspx

Auto-resolving a hostname in WCF Metadata Publishing

I am running a self-hosted WCF service. In the service configuration, I am using localhost in my BaseAddresses that I hook my endpoints to. When trying to connect to an endpoint using the WCF test client, I have no problem connecting to the endpoint and getting the metadata using the machine's name. The problem that I run into is that the client that is generated from metadata uses localhost in the endpoint URLs it wants to connect to. I'm assuming that this is because localhost is the endpoint URL published by metadata. As a result, any calls to the methods on the service will fail since localhost on the calling machine isn't running the service.
What I would like to figure out is if it is possible for the service metadata to publish the proper URL to a client depending on the client who is calling it. For example, if I was requesting the service metadata from a machine on the same network as the server the endpoint should be net.tcp://MYSERVER:1234/MyEndpoint. If I was requesting it from a machine outside the network, the URL should be net.tcp://MYSERVER.mydomain.com:1234/MyEndpoint. And obviously if the client was on the same machine, THEN the URL could be net.tcp://localhost:1234/MyEndpoint.
Is this just a flaw in the default IMetadataExchange contract? Is there some reason the metadata needs to publish the information in a non-contextual way? Is there another way I should be configuring my BaseAddresses in order to get the functionality I want?
Thanks,
Mike
What .NET version are you using? If you're using .NET 4.0, add the UseRequestHeadersForMetadataAddressBehavior to your service host:
UseRequestHeadersForMetadataAddressBehavior urh =
new UseRequestHeadersForMetadataAddressBehavior();
serviceHost.Description.Behaviors.Add(urh);
Obviously, this needs to be done prior to opening the service host.
If you're using .NET 3.5, there's a hotfix that adds this behavior: support.microsoft.com/kb/971842.

wcf service stops after few requests

I am working on an application where i am using a wcf service. I am currently hosting my service on localhost and accessing it from there only by adding the service reference in my project. On one of my page i am sending request on change of selected index on dropdown list. It works fine for first few requests but suddenly stops after that giving following excsption
"Failed to invoke the service. Possible causes: The service is offline or inaccessible; the client-side configuration does not match the proxy; the existing proxy is invalid. Refer to the stack trace for more detail. You can try to recover by starting a new proxy, restoring to default configuration, or refreshing the service."
How can service stop without any reason and that too from my localhost. It only works for first 3-4 requests. In service i am just sending a integer and getting back the records on its basis using a class in a generic list.
Thanks in advance
What protocol / bindings are you using? Can you show us the config? Anything inside the <system.serviceModel> on both the server and the client side.
Do you maybe create a client proxy and call the service method and not properly close and dispose of the client proxy? In that case, you might run out of connections at some point - but that's next to impossible to tell without some code to see what you're doing. Can you show us the service contract in question, and the code how you call it from the client side?

Silverlight WCF calls work in IE but not in FF

I'm having a WCF service deployed on one of my servers, and my Silverlight app on the other server. The problem I'm having is running it in Firefox 3.5. Opening in IE 6/7 works great, but when I open it in Firefox it loads the app, but on calling WCF service i get this:
An error occurred while trying to make a request to URI 'http://10.1.1.20:87/MyService.svc'. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent.
(The connection works over VPN so don't worry about the IP address)
I have encountered a similar problem and after a lot of research I found that adding the following line of code into the constructor of my UserControl solved the problem:
bool registerResult = WebRequest.RegisterPrefix("http://", WebRequestCreator.BrowserHttp);
More information about the WebRequest member can be found here.