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more progress :D

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Rusty Striker 2024-12-17 20:41:30 +02:00
parent d49131bc67
commit c4524fb62e
Signed by: RustyStriker
GPG key ID: 87E4D691632DFF15
6 changed files with 210 additions and 51 deletions
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139
client/Program.cs
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@ -4,58 +4,161 @@ using System.Text;
using System.Threading.Tasks;
using System.Security.Cryptography;
using System.Linq;
using System.IO;
using lib;
namespace Client;
public class Program
{
static void Main(string[] args)
static async Task Main(string[] args)
{
RSA key = RSA.Create(512);
Console.WriteLine($"key: {key.ExportRSAPrivateKey().Length}");
Console.WriteLine(key.ExportRSAPublicKeyPem());
string user = args
.SkipWhile(a => !new[] { "-p", "--phone" }.Contains(a)) // search for the option
.Skip(1) // skip the `-u/--user` itself to get the value
.FirstOrDefault() ?? "0000"; // get the value or deafult if it doesnt exist
// On boot, check if a key is available
RSA serverKey = LoadRSAFromFile("key_server.pem")!;
RSA pubKey = LoadRSAFromFile($"pubkey_{user}.pem") ?? RSA.Create(2048);
RSA privKey = LoadRSAFromFile($"privkey_{user}.pem") ?? pubKey;
SaveRSAKeys(user, pubKey, privKey);
using TcpClient client = new("127.0.0.1", 12345);
byte[] toSend = Encoding.ASCII.GetBytes("hello server");
var stream = client.GetStream();
// First contact init
bool needsRegister = pubKey == privKey || args.Any(a => new[] { "-fr", "--force-register" }.Contains(a));
Aes sk = Aes.Create(); // creates an AES-256 key
if (needsRegister)
{
while(true) {
try {
await RegisterClient(user, pubKey, privKey, serverKey, sk, stream);
}
catch (Exception ex) {
Console.WriteLine("Failed registration process");
Console.WriteLine("Exception: " + ex.Message);
Console.WriteLine("Stack: " + ex.StackTrace);
}
}
}
else
{
}
var inputTask = Task.Run(async () => await HandleUserInput(client, stream));
var serverInput = Task.Run(async () => await HandleServerInput(client, stream));
_ = Task.WaitAny(inputTask, serverInput);
}
static async Task HandleUserInput(TcpClient client, NetworkStream stream) {
while(client.Connected) {
async static Task RegisterClient(string user, RSA pub, RSA priv, RSA server, Aes sk, NetworkStream stream)
{
byte counter = 0;
// first send the `Register` message
byte[] pubBytes = pub.ExportRSAPublicKey();
byte[] data = new byte[16];
Array.Copy(Utils.NumberToBytes(user), data, 8);
Array.Copy(BitConverter.GetBytes(pubBytes.Length), 0, data, 8, 4);
Array.Copy(BitConverter.GetBytes(sk.Key.Length), 0, data, 12, 4);
byte[] msg = Request.CreateRequest(RequestType.Register, ref counter, data);
byte[] finalPayload = [.. msg, .. pubBytes, .. sk.Key];
// signing a hash here is pretty useless tbh
// if oscar is changing this message somehow it will just fail the registration process and will restart eventually
// so kinda pointless, esp when its signed with the server's key
byte[] enc = server.Encrypt(finalPayload, RSAEncryptionPadding.OaepSHA256);
await stream.WriteAsync(enc);
// get the 6 digit code
byte[] digits = new byte[6];
await stream.ReadExactlyAsync(digits, 0, 6);
// print the 6 digit code
Console.WriteLine($"[{DateTime.Now}] 6 digit code: {string.Join(' ',digits.Select(d => d.ToString()))}");
// get the 6 digit code from the user
while(true) {
string? code = Console.ReadLine()?.Trim();
if(code == null || code.Take(6).Any(c => !char.IsDigit(c))) {
Console.WriteLine("Invalid code!");
continue;
}
byte[] codeBytes = code
.Take(6) // take the first 6 characters
.Select(d => byte.Parse(d.ToString())) // parse into bytes
.ToArray();
msg = Request.CreateRequest(RequestType.ConfirmRegister, ref counter, codeBytes);
byte[] signed = priv.SignData(msg, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
enc = sk.EncryptCfb(msg, Array.Empty<byte>(), PaddingMode.None); // no reason to encrpy the signature
finalPayload = [.. enc, .. signed]; // should be 128 (enc) + 256 (signed)
await stream.WriteAsync(finalPayload);
int incoming = await stream.ReadAsync(enc);
msg = sk.DecryptCfb(enc[..incoming], Array.Empty<byte>(), PaddingMode.Zeros);
string r = Encoding.UTF8.GetString(msg);
if(r == "OK") {
Console.WriteLine("Registration process complete");
break;
}
}
}
static RSA? LoadRSAFromFile(string file)
{
if (File.Exists(file))
{
string content = File.ReadAllText(file);
RSA k = RSA.Create();
k.ImportFromPem(content);
return k;
}
return null;
}
static void SaveRSAKeys(string user, RSA pub, RSA priv)
{
File.WriteAllText($"pubkey_{user}.pem", pub.ExportRSAPublicKeyPem());
File.WriteAllText($"privkey_{user}.pem", priv.ExportRSAPrivateKeyPem());
}
static async Task HandleUserInput(TcpClient client, NetworkStream stream)
{
while (client.Connected)
{
string? input = Console.ReadLine();
if(input == null) {
if (input == null)
{
await Task.Delay(100);
continue;
}
else if(input.StartsWith('/')) {
else if (input.StartsWith('/'))
{
// Commands :D, i like commands
switch(input.ToLower()) {
switch (input.ToLower())
{
case "/quit":
case "/exit":
case "/q!":
return;
}
}
else {
else
{
stream.Write(Encoding.ASCII.GetBytes(input));
Console.WriteLine($"[{DateTime.Now}]Sent to server: {input}");
}
}
}
static async Task HandleServerInput(TcpClient client, NetworkStream stream) {
static async Task HandleServerInput(TcpClient client, NetworkStream stream)
{
byte[] buffer = new byte[1024];
while(client.Connected) {
while (client.Connected)
{
int readLen = await stream.ReadAsync(buffer);
if(readLen != 0) {
if (readLen != 0)
{
string fromServer = Encoding.ASCII.GetString(buffer[..readLen]);
Console.WriteLine($"[{DateTime.Now}] From server: {fromServer}");