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In numerous instances during penetration tests.

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We as hackers have found ourselves in situations where we urgently required a TCP client, whether it

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was to test services, send malformed data, perform fuzzing or tackle a range of other tasks.

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So the need for TCP client has been prevalent.

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However, operating within the confines of large enterprise environments often means forfeiting the

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luxury of creating our tools.

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So now we will write our code and I will explain.

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First, we will import the sockets here.

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Socket is a socket here and we will, for example, let's make the target host.

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Target host.

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Let's make the google w-w-w dot google.com.

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Of course, the port of Http is 80 target target port here is 80 http protocol.

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And now we will create a socket object.

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So client here we will socket dot socket here.

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So firstly we will here, let's try it.

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And the second first that it gets address family and then socket kind.

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Right.

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So socket.

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That a of init here and socket.

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But sock stream.

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And here then we will connect the client.

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So client dot.

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Connect.

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Connect here and now.

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Firstly, we will enter the target host and target port, right?

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And here we will send some data.

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In order to do that, we will use the client dot send method and here we will get we will enter B here

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get.

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Http and 1.1 R and n host.

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Now we will enter Google.com and after that we will inside this.

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Print.

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N r n here.

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And after that we will after sending, we will need to receive data to show print on the screen.

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Right?

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So now we will print the response.

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Response dot decode.

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And after that.

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It will add another here.

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Client that clause.

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That's it.

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So here we after that we send sending some data.

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Of course, we need to get the create this response here.

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And in order to do that, of course, we need to personally do this like that.

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And after that, getting the response from the client.

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We will open the here and now we will get the response.

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So response.

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Client client.

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Client that rests here.

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And 4096.

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That's it.

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So here, let's run this.

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And as you can see here, we got this.

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Let's actually change this to double, double, double dot.

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Auxilia.

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Com and here.

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House.

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And as you can see here, we got a bad request here.

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We have a firewall on our website.

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So to create a TCP client, we begin by initializing this.

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Actually, I'll get my pen, my pen here, and I will draw things on the screen.

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So to create a TCP client.

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We begin by initializing.

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A socket object.

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A socket object with n parameters.

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A if init and sock stream.

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And the af init parameter signifies the use of the standard IPV four ipv four protocol and the address

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or hostname.

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While the SOC stream here indicates that this is t c p protocol.

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Right.

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So and indicates that the client will operate over TCP.

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Next, we establish a connection between the client and server here.

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Connect with this code here.

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Actually.

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Yes.

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So we next we establish the connection with client and server, ensuring that they can communicate to

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send data to the server.

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We convert the we convert data into bytes by bytes and transmitted.

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So the final statement was receiving a response from the server which is here.

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So the and after that we are printing out here, right?

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So and after that we are closing that.

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So the code here provides a simple and commonly used form of TCP client.

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However, it's important to acknowledge that certain assumptions made by these quotes, this code here

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regarding sockets here.

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So firstly, it assumes that the connection will always succeed.

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Secondly, it assumes that the server expects the client to send data first, even though some servers

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may anticipate sending data to the client and the waiting a response.

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Lastly, it assumes that the server will consistently return data promptly so these assumptions are

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primarily made for the sake of simplicity.

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So while there are various approaches to handling, blocking sockets, exception handling and similar

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aspects, penetration testers often prioritize efficiency and expedience when building quick and dirty

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tools for reconnaissance or exploitation purposes.

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Consequently, in this lecture we will omit the inclusion inclusion for more advanced socket handling

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techniques.