Module tcp_handler::encrypt

Encryption protocol. Without compression.

With encryption, you can keep the data safe from being intercepted by others.

Example

use anyhow::Result;
use bytes::{Buf, BufMut, BytesMut};
use tcp_handler::encrypt::*;
use tokio::net::{TcpListener, TcpStream};
use variable_len_reader::{VariableReadable, VariableWritable};

#[tokio::main]
async fn main() -> Result<()> {
    let server = TcpListener::bind("localhost:0").await?;
    let mut client = TcpStream::connect(server.local_addr()?).await?;
    let (mut server, _) = server.accept().await?;

    let c_init = client_init(&mut client, &"test", &"0").await;
    let s_init = server_init(&mut server, &"test", |v| v == "0").await;
    let mut s_cipher = server_start(&mut server, s_init).await?;
    let mut c_cipher = client_start(&mut client, c_init).await?;

    let mut writer = BytesMut::new().writer();
    writer.write_string("hello server.")?;
    let mut bytes = writer.into_inner();
    c_cipher = send(&mut client, &mut bytes, c_cipher).await?;

    let (reader, s) = recv(&mut server, s_cipher).await?;
    let mut reader = reader.reader(); s_cipher = s;
    let message = reader.read_string()?;
    assert_eq!("hello server.", message);

    let mut writer = BytesMut::new().writer();
    writer.write_string("hello client.")?;
    let mut bytes = writer.into_inner();
    s_cipher = send(&mut server, &mut bytes, s_cipher).await?;

    let (reader, c) = recv(&mut client, c_cipher).await?;
    let mut reader = reader.reader(); c_cipher = c;
    let message = reader.read_string()?;
    assert_eq!("hello client.", message);

    Ok(())
}

This protocol is like this:

        ┌────┬────────┬────────────┐ (It may not be in contiguous memory.)
in  --> │ ** │ ****** │ ********** │
        └────┴────────┴────────────┘
          Nonce│
          │    │─ Copy once.
          v    v
        ┌────┬────────────────────┐ (In contiguous memory.)
        │ ** │ ****************** │
        └────┴────────────────────┘
          │
          │─ Encrypt in-place
          v
        ┌────────────────────┐ (Encrypted bytes.)
out <-- │ ****************** │
        └────────────────────┘

Functions

• client_init
  Init the client side in tcp-handler encrypt protocol.
• client_start
  Make sure the client side is ready to use in tcp-handler encrypt protocol.
• recv
  Recv message in encrypt tcp-handler protocol.
• send
  Send message in encrypt tcp-handler protocol.
• server_init
  Init the server side in tcp-handler encrypt protocol.
• server_start
  Make sure the server side is ready to use in tcp-handler encrypt protocol.