Hi i am running a server socket created in java that accepts requests from a client that uses HTTP url to connect and send web requests.
client does this:
URLconnection.opeonConnection(new Url(www.hello.com/hi));
on my server socket it retrieves a Socket object.
is it possible to retrieve the url www.hello.com/hi url that was passed to this socket conection?
Probably, by parsing the client's HTTP headers:
You can get the "/hi" portion with some work. The URL Connection class will use the HTTP protocol to submit some HTTP headers, along with a GET request as "GET /hi HTTP/1.1". The "/hi" portion comes from the URL.
The "www.hello.com" part might be more difficult. The browser will provide the host and port (if port is given) portion of the URL in a "Host: " header. It's likely that your networking infrastructure may contain proxies or load balancers that forward the request on to the final backend server, and if the proxies aren't configured correctly, they won't maintain the original host header. Try it yourself, and talk to your network administrators if it's not working as you expect.
If you want to see what the URL connection class will send to your server you can get an idea by pointing your browser to this URL: http://request.urih.com/. The "request header: raw source" section shows you the HTTP headers sent by an HTTP client (your browser).
The "HTTP Headers for Dummies" web page is also a good introduction to HTTP headers
Yes it is possible to get the String but not the way you likely want it.
You can implement a HTTP-Server (see RFC 2616). But it is likely that you don't want this.
You can also use a Servlet container like Tomcat or Jetty and write a Servlet to use HTTP. With this the Servlet container does all the protocol and you can concentrate on doing the business logic.
As you state you're building a proxy, you're already asking the wrong question.
An HTTP proxy only has to deal with one command: the CONNECT command. You just have to:
Read this one line from the client.
Connect to the target indicated in the command.
Reply with success or failure.
If success, start copying bytes in both directions.
But I don't know why you're even implementing an HTTP proxy when there are dozens of free working ones already in existence.
In in the interface Socket there is getRemoteSocketAddress(). It returns a SocketAddress, and if the implementation of SocketAddress is InetSocketAddress, try to call getHostString().
SocketAddress address =yourSocket.getRemoteSocketAddress().
String address=((InetSocketAddress)address).getHostString();
Hope it helps.
Related
I want to make proxy server to modify my request body, header before forward to real server.
I can just image, how to work in http proxy.
However, I want to know exactly how to work socket proxy, https proxy and http proxy.
I want to read official proxy server specification, but I cannot find it.
Could you explain where can I find the proxy spec?
I am trying to simulate a response from a web server login confirmation to a windows application. I have the captured packets that detail the conversation between the server and the application for successful login already as it is my application, this is for debugging and MIME simulation to test application and network security. communications create what I hope can be a custom foolproof way to prevent a MIME but I dont have a way to test it, so here I am to ask for guidance.
How would I go about simulating the response from the server to the application?
I have some idea in the direction I would possibly need to go to achieve my desired outcome:
Utilizing my network:
I have a Linux machine set up as a dynamic router, dhcp, routing, and my Linksys router just acts as an access point and ethernet switch.
1: Set up web server on Linux machine.
2: redirect traffic from application port to Linux server.
3: run server-side script to respond to application request using packets captured to establish replay successful login to server.
So, I am kinda new to using Linux tools. I have setup a Linux router, captured basic information utilizing Wireshark, and am able to program in VB, javascript, some java. I have not done much network-oriented programming other than some simple communication for authentication I have successfully established.
Any information to point me in the right direction I am grateful for!
Most logins use encryption (https / TLS) so capturing the packets won't help.
If not, the packets will form a http request, and you should be able to see the format of the request, whether the login credentials are part of the URL for GET or part of the http body for POST. It is not hard to create your own http request.
How are parameters sent in an HTTP POST request?
Each http request will be followed by an http response from the server, and the format of the headers or body will contain the login result (http requests and responses are similar in format, but the headers are not the same).
More sophisticated logins may involve a series of requests/responses.
You will need to write a simpler server to receive the requests and send the responses. Java is probably your best choice, given the languages you know, plus there will be plenty of examples online. With JS it may be possible but for the most part JS is used in browsers, so not a great choice. VB is a Windows language not supported on Linux.
Context:
I have never created something or worked on this subject before but I have done my research and now I know what's the subject.
I have a virtual server machine(machineVM) and not a virtual client machine (machineA).
I should send a HTTP request from machineVM to machineA to a specific port. machineVM sees and knows machineA,i.e, it knows client name of machineA(myClient) via the HTTP request .
I'd like to say to machineA: "I have a document for you, come and get it.". On machineA I will have a windows service that will listen to that port and do its stuff.
That HTTP request should look like:
http:\\myClient:port/request_message_body
What are the possible wayouts to achieve the task?
HTTP POST ?
I am aware that HTTP uses port 80. How to decide and which port to use, which port will windows service listen, on which port should HTTP request be sent?
In this request_message_body I'd like to share a path to the folder from which machineA could fetch the document and to specify server and port.
How to format HTTP request correctly?
I should be able to create windows service that listens to a port, because I've created few services before, but I really need help with creation of this HTTP request and sending it.
Any help will be appreciated.
If you want to roll-your-own solution, you'll probably want to build on top of httpclient
There's also loads of libraries out there to help you to build restful webservices (springws, resteasy, jaxrs etc)
Solved!
Thank you #Gimby and #user2412816. You guys made me go through my code again and it was my mistake, like the most of the time. :-)
I am actually trying to send SMS using CDYNE and their API. To do that, I am using Java and HttpGet and HttpClient object (Httpcore and HttpClient libs). I am sending the request to an https URL, sending the parameters like https://www.example.com/SecureREST/SimpleSMSsend?PhoneNumber=ABC&Message=XYZ
Would it be a security issue that I am using a GET request and that all parameters are in the URL it self? What if the content of the Message parameter in the URL contains sensitive informations? Could someone sniff the network to get hold of the content or is is safe since the request is sent using HTTPS?
My believe is that only the www.example.com is visible during the handshake process and that once this is done, everything is encrypted but I just want to make sure.
Wikipedia is pretty clear about this:
Note that when a client sends an HTTPS request, the hostname and port of the URL are unencrypted... However, all other parts of the HTTPS request, including the URL path and query parameters, can only be decrypted by the destination site or by an interposing intermediary that terminates the HTTPS connection on behalf of the site.
So your belief is right. Only the hostname and port are openly visible; the rest of the URL is encrypted.
I'm experiencing a strange problem that I'm not able to figure out. The proxy when used in my Java code to make non-SSL requests always gives error informing me that I cannot send SSL requests to the specified port (whereas I'm not even trying to send any SSL request), however the same proxy when configured in my Firefox browser works like a charm and I can browse all web sites normally. Note that using the same Java code, I can send requests to 443 port alone. But that's because the proxy detects that the requests are SSL, and that's why it only allows them to pass through 443 port.
I don't have the option to use -Dhttp.proxyHost and -Dhttps.proxyHost options with me because they simply won't work on the Socket objects, I would need a Socks proxy which I don't have access to. So I opted to go with commons-httpclient-3.1.jar, and used ProxyClient object to obtain the socket.
This is the code I'm using to obtain a socket:
// Proxy Client
ProxyClient client = new ProxyClient();
client.getHostConfiguration().setHost("google.com", 80);
client.getHostConfiguration().setProxy("corporate-proxy", 80);
ConnectResponse response = client.connect();
Socket socket = response.getSocket();
if (socket == null) {
System.err.println(response.getConnectMethod().getStatusLine());
}
and this is the exact error message that is printed by my System.err.println() statement:
HTTP/1.1 502 Proxy Error ( The specified Secure Sockets Layer (SSL) port is not allowed. ISA Server is not configured to allow SSL requests from this port. Most Web browsers use port 443 for SSL requests. )
Please don't suggest me to use URLConnection because I don't need the proxy for HTTP requests alone.
I have also tried to explicitly specify the protocol to be http without any luck:
client.getHostConfiguration().setHost("google.com", 80, Protocol.getProtocol("http"));
Any suggestions on how to configure this ProxyClient object, so that the proxy server doesn't see requests to be coming as SSL requests?
Thanks.
UPDATE
I seem to have figured out the reason why the ISA server thought I'm using SSL. Actually the statement client.connect(); creates a socket that is connected, via the HTTP CONNECT method, to a proxy. The Java doc says that, even though HTTP CONNECT proxying is generally used for HTTPS tunneling, the returned socket will not have been wrapped in an SSL socket.
But for ISA, it would still think about this kind of HTTP request as an SSL request. And when it sees that this SSL request is not on 443, instead it is on some other port, it straight away rejects it.
So now the problem instead is that how do I make the client.connect() call to send an HTTP GET or HTTP HEAD instead of HTTP CONNECT..
Sorry, but I think this is a limitation os ISA Server and not a problem of ProxyClient. See the article here to configure ISA Server to allow to connect to other port, beside 443. I think ISA Server don´t recognize you request because it isnt in a HTTP 1.x request.
Assuming you're using the Apache HttpClient, your code is different from a similar sample on the Apache web site. It makes use of some other techniques to make the request, perhaps that's where the difference is. See the samples here, and particularly this one.