Server side SSL socket in Visual Basic (VB6) - sockets

I have to edit an existing VB6 application that deals with Socket requests from client endpoints. What are tools (Classes/methods) that allow one to make an SSL Socket instead of a classic socket. I found out that there is a control called WinSock, but I don't know whether it is suitable for the server's tasks or not.
Any kind of help will be appreciated.
Thanks.

Related

Is it possible to create a proxy server for any application?

I've been trying to create a proxy server to analyze TCP packages sent between my computer and a game server.
Now I know that you can do this kind of stuff with Wireshark, but I want to understand the logic of it and how the connections are made.
My main question is that I don't know where to start from. I have the server IP and port from Process Explorer and have the basic socket programming knowledge in python, but as I said, I don't know what to code.
Am I supposed to write a socket that hijacks the incoming TCP connection and forward it to my localhost? but then how would my client send data to server?
As you can see, I'm a bit lost, and I would be very happy if someone could put me in a correct path (what should I research?).
Thank you in advance.
I think there is a useful tools can help you: iptables and netfilter. Using this, you can hijacks the incoming TCP connection and forward it to your localhost easily.

How can I create a network proxy programming?

Excuse me. I speak poor English.
I am trying to create a network proxy programming with sock5 protocol. But I have no way to learn it, I can't figure out how a proxy programming works especially the followings:
What is the difference and association between socks5 and the Shadowsocks ?
Can I set a the network proxy configure in macOs instead of using swift or oc ?
such as enabling this check button(socks5 proxy) and filling the specific configure using a language instead of swift or oc:
configure
Once I set the option on macOs in the Question 2,what kind of data will the programming get if it listening the network?
e.g. will the macOs automatically forward the all new TCP connections to 127.0.0.1:1086 and automatically make the connections confirm to the socks5 request standard?
If so, why the final processing programming (transmit the datas to the real remote proxy-server) can make a successful connection? Instead of a forever loop(a.programming create a socket to remote proxy-server -> b. macOs automatically forward it to 127.0.0.1:1086 and make the connection confirm to the socks5 request standard -> a.)
Is it called as a proxy-client? or local proxy-server? what is the job of it. Why do I set a proxy address as a local one instead of a direct remote server?
Why when I setting a fake socks5 option in macOs network proxy options, a UDP programming can still work successfully?
If you can UNDERSTAND CHINESE:
Chinese language
The follow answers are based on my own experience and opinion.
1、socks5 is an Internet protocol that exchanges network packets between a client and server through a proxy server. Sockes
while Shadowsocks is a software use this protocol.
2 、Yes,you can. Install a Shaowsocks don't need any
Programming language, actually it like installing a EXE file on Windows or pkg on MacOS, it's just a software.
3、Socks5 is an Internet protocol like a language between two computer.
The software's message run on you computer will be "translated" by Shadowsocks.
Those translated message will be sent to the remote service (also run a Shadowsocks) then the service can send message to those "blocked" Webs' services.
4、The remote service can be called an proxy service.The local don't do anything except be "translated" by Shadowsocks. Look this picture.
5、The QQ don't use the port 1080, Shadowsocks need a fixed port to "translate" message.

Best practice for connecting to a TCP service with Play

I want to connect to a locally running TCP service from a web application I'm building using the Play framework and scala.
I'm not sure how to open this connection and send commands to it, should I be writing raw socket code? Also, how should I be managing the connection? Can I just open the connection once and send commands from each web request to it? What if the connection is closed or falls over?
Not sure Pay will be of much help here, most of its modules focus on HTTP communication. You should have a look at Akka-IO though.

Bluetooth: how to create a socket for connecting to a service with specific UUID with Bluez?

I am working with the BlueZ libraries for managing the bluetooth stack under linux. I am trying to open a socket that should connect with a specific service whose UUID is known. I have successfully tried to open sockets between a server and a client following the examples here:
http://people.csail.mit.edu/albert/bluez-intro/c404.html
where it is also described how to explore services in a remote host; however, what I cannot figure out is how to specify the UUID while connecting the socket. This is something quite straightforward on other contexts, as it happens when using Android libraries; however, with BlueZ I haven't found examples on the web.
Thanks for the help!
Stefano
-- added some details in a reply... don't know if it's right or not; if not, sorry
thanks for your help!
In my post I said I wanted to connect a socket with a specified UUID since I had in mind a function like createRfcommSocketToServiceRecord as can be found in:
http://developer.android.com/reference/android/bluetooth/BluetoothDevice.html#createRfcommSocketToServiceRecord%28java.util.UUID%29
which returns a socket given a certain UUID. I am developing two softwares, one being the client and the other the server, therefore it's a service I am creating, not a standard one. I publish such service on the server with a specified UUID, and I would like to connect to it from the client. The server is running fine, since with an android platform, exploiting the mentioned createRfcommSocketToServiceRecord method, I am able to connect to the server with the right service.
The example you posted is very clear as well, but unfortunately it is in Python, while (I forgot to point out) I am using Bluez as a C library. I am able to exploit the SDP and inspect services on a remote server; however, when it is the time of setting up the socket, I don't see how to specify the port. I thought about the rc_channel, but as far as I understood it is the bluetooth channel (ranging from 1 to 11 or something similar). Could you please point out Where I should be able to specify the port while creating the socket in the client? And where am I able to find the right port in the complex structure the sdp is dealing with? -- referred to:
http://people.csail.mit.edu/albert/bluez-intro/x604.html
Thanks again for the help!
You don't connect sockets by UUID. You use a socket to connect to remote device and browse its SDP to discover the UUIDs it offers, and map that to a socket port. Here's an example of this process using PyBluez, python wrappers above BlueZ
http://people.csail.mit.edu/albert/bluez-intro/x290.html

How do online port checkers work?

For example http://www.utorrent.com/testport?port=12345
How does this work? Can the server side script attempt to open a socket?
There are many ways of accomplishing this through server-side scripting. As #Oded mentioned, most server-side handlers are capable of initiating socket connections on arbitrary ports, and most of those even have dedicated port-scanning packages/libraries (PHP has one in the PEAR repository, Python's 'socket' module makes this type of tasks a breeze, etc...)
Keep in mind that on shared host platforms, socket connections are typically disabled for security purposes.
Another way that is also very easy to accomplish is to use a command-line port-scanner such as nmap from your server-side script. i.e in PHP, you would do echo ``nmap -p $port $ip\
The server side script will try to open a connection on the specified port to the originating IP.
If there is no response (the attempt will timeout), this would be an indication that the port is not open.
The server can try, as #Oded said. But that doesn't ensure the receiver will respond.
Typically, something like this happens:
The URL request contains instructions about which port to access. The headers that your browser sends include information about where the request is originating from.
Before responding to the request, the server tries to open a port and checks if this is successful. It waits a while before timing out.
The webpage is rendered dynamically based on the results of this test.
The response is returned to you containing the results.
Sometimes steps (2) and (3) will be replaced with an AJAX callback, which allows the response to return sooner.