S3 Proxy

A browser configured for the HTTP protocol sends client requests not directly, but through a proxy server, which in turn sends them on its own behalf to the destination host. The proxy server here acts as a link between the computer and the requested resource, and the response it immediately sends to the client.

Bouncy Castle is a popular cryptography library in C#. If you want to parse and extract Certificate Signing Request (CSR) extensions using Bouncy Castle, you can follow these steps

Add Bouncy Castle Library

First, make sure you have the Bouncy Castle library added to your project. You can do this via NuGet Package Manager:

Install-Package BouncyCastle

Parse CSR:

Use Bouncy Castle to parse the CSR. The following code demonstrates how to parse a CSR from a PEM-encoded string:

using Org.BouncyCastle.Pkcs;
using Org.BouncyCastle.OpenSsl;
using Org.BouncyCastle.X509;
using System;
using System.IO;

class Program
{
    static void Main()
    {
        string csrString = File.ReadAllText("path/to/your/csr.pem");

        Pkcs10CertificationRequest csr = ParseCSR(csrString);

        // Now you can work with the parsed CSR
    }

    static Pkcs10CertificationRequest ParseCSR(string csrString)
    {
        PemReader pemReader = new PemReader(new StringReader(csrString));
        object pemObject = pemReader.ReadObject();

        if (pemObject is Pkcs10CertificationRequest csr)
        {
            return csr;
        }

        throw new InvalidOperationException("Invalid CSR format");
    }
}

Extract Extensions:

Once you have the CSR parsed, you can extract extensions using the GetAttributes method. Extensions in a CSR are typically stored in the Attributes property. Here's an example:

foreach (DerObjectIdentifier oid in csr.CertificationRequestInfo.Attributes.GetOids())
{
    Attribute attribute = csr.CertificationRequestInfo.Attributes[oid];

    // Work with the attribute, e.g., check if it's an extension
    if (oid.Equals(PkcsObjectIdentifiers.Pkcs9AtExtensionRequest))
    {
        X509Extensions extensions = X509Extensions.GetInstance(attribute.AttrValues[0]);

        // Now you can iterate over extensions and extract the information you need
        foreach (DerObjectIdentifier extOID in extensions.ExtensionOids)
        {
            X509Extension extension = extensions.GetExtension(extOID);
            // Process the extension
        }
    }
}

Modify the code according to your specific requirements and the structure of your CSR. The example assumes a basic structure, and you may need to adapt it based on your CSR format and the extensions you're interested in.

To view the proxy settings on your computer, you can follow these steps depending on the operating system you are using:

For Windows:
- Press the Windows key + R to open the Run dialog box.
- Type "inetcpl.cpl" (without quotes) in the Run dialog box and press Enter.
- In the Internet Properties window, go to the Connections tab.
- Click on the "LAN settings" button.
- In the LAN Settings window, you will see the proxy server settings. If there is a checkmark in the "Use a proxy server for your LAN" box, it means you are using a proxy server.

For macOS:
- Click on the Apple menu in the top-left corner of your screen.
- Select "System Preferences" from the dropdown menu.
- Click on "Network" in the System Preferences window.
- Select the network connection you are using (e.g., Wi-Fi, Ethernet) from the left pane.
- Click on the "Advanced" button.
- In the Advanced window, go to the "Proxies" tab to view the proxy settings.

On the PC you can use SOCKS5 proxies, for example, through the browser Firefox. There are such a function in the settings, you just need to activate it. The only nuance: the connection speed or ping indicators in this case may be slowed down.

To check a proxy for blacklisting, it is necessary to use special tools developed for this purpose. Many proxy-checkers provide free online IP-address verification and provide detailed information related to the proxy servers security. To get it, just enter the IP address of the proxy and click on the "Verify" button.