67 lines
2.1 KiB
C#
67 lines
2.1 KiB
C#
using System.Net;
|
|
using System.Net.Sockets;
|
|
using System.Security.Cryptography;
|
|
using System.Text;
|
|
|
|
new Thread(ServerWorker).Start();
|
|
new Thread(ClientWorker).Start();
|
|
return;
|
|
|
|
static void ClientWorker()
|
|
{
|
|
using var socket = new Socket(SocketType.Stream, ProtocolType.Tcp);
|
|
socket.Connect(new IPEndPoint(IPAddress.Loopback, 1234));
|
|
|
|
using var stream = new NetworkStream(socket);
|
|
|
|
// read public key from server
|
|
using var reader = new BinaryReader(stream);
|
|
using var writer = new BinaryWriter(stream);
|
|
using var rsa = new RSACryptoServiceProvider(2048);
|
|
rsa.ImportParameters(new RSAParameters
|
|
{
|
|
Modulus = reader.ReadBytes(reader.ReadInt32()),
|
|
Exponent = reader.ReadBytes(reader.ReadInt32())
|
|
});
|
|
|
|
while (Console.ReadLine() is { } line)
|
|
{
|
|
// encrypt line and send to server
|
|
byte[] encrypted = rsa.Encrypt(Encoding.UTF8.GetBytes(line), RSAEncryptionPadding.OaepSHA1);
|
|
writer.Write(encrypted.Length);
|
|
writer.Write(encrypted);
|
|
}
|
|
}
|
|
|
|
static void ServerWorker()
|
|
{
|
|
using var socket = new Socket(SocketType.Stream, ProtocolType.Tcp);
|
|
socket.Bind(new IPEndPoint(IPAddress.Any, 1234));
|
|
socket.Listen(1);
|
|
|
|
// generate RSA key pair
|
|
using var rsa = new RSACryptoServiceProvider(2048);
|
|
RSAParameters publicKey = rsa.ExportParameters(false);
|
|
|
|
// accept client socket
|
|
using Socket client = socket.Accept();
|
|
using var stream = new NetworkStream(client);
|
|
|
|
// write public key
|
|
using var writer = new BinaryWriter(stream);
|
|
writer.Write(publicKey.Modulus!.Length);
|
|
writer.Write(publicKey.Modulus);
|
|
writer.Write(publicKey.Exponent!.Length);
|
|
writer.Write(publicKey.Exponent);
|
|
|
|
while (true)
|
|
{
|
|
// read encrypted line from client
|
|
using var reader = new BinaryReader(new NetworkStream(client));
|
|
int length = reader.ReadInt32();
|
|
byte[] encrypted = reader.ReadBytes(length);
|
|
byte[] decrypted = rsa.Decrypt(encrypted, RSAEncryptionPadding.OaepSHA1);
|
|
Console.WriteLine($"Client sent: {Encoding.UTF8.GetString(decrypted)}");
|
|
}
|
|
}
|