tokio_rustls/common/
handshake.rs

1use std::future::Future;
2use std::ops::{Deref, DerefMut};
3use std::pin::Pin;
4use std::task::{Context, Poll};
5use std::{io, mem};
6
7use rustls::server::AcceptedAlert;
8use rustls::{ConnectionCommon, SideData};
9use tokio::io::{AsyncRead, AsyncWrite};
10
11use crate::common::{Stream, SyncWriteAdapter, TlsState};
12
13pub(crate) trait IoSession {
14    type Io;
15    type Session;
16
17    fn skip_handshake(&self) -> bool;
18    fn get_mut(&mut self) -> (&mut TlsState, &mut Self::Io, &mut Self::Session);
19    fn into_io(self) -> Self::Io;
20}
21
22pub(crate) enum MidHandshake<IS: IoSession> {
23    Handshaking(IS),
24    End,
25    SendAlert {
26        io: IS::Io,
27        alert: AcceptedAlert,
28        error: io::Error,
29    },
30    Error {
31        io: IS::Io,
32        error: io::Error,
33    },
34}
35
36impl<IS, SD> Future for MidHandshake<IS>
37where
38    IS: IoSession + Unpin,
39    IS::Io: AsyncRead + AsyncWrite + Unpin,
40    IS::Session: DerefMut + Deref<Target = ConnectionCommon<SD>> + Unpin,
41    SD: SideData,
42{
43    type Output = Result<IS, (io::Error, IS::Io)>;
44
45    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
46        let this = self.get_mut();
47
48        let mut stream = match mem::replace(this, MidHandshake::End) {
49            MidHandshake::Handshaking(stream) => stream,
50            MidHandshake::SendAlert {
51                mut io,
52                mut alert,
53                error,
54            } => loop {
55                match alert.write(&mut SyncWriteAdapter { io: &mut io, cx }) {
56                    Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
57                        *this = MidHandshake::SendAlert { io, error, alert };
58                        return Poll::Pending;
59                    }
60                    Err(_) | Ok(0) => return Poll::Ready(Err((error, io))),
61                    Ok(_) => {}
62                };
63            },
64            // Starting the handshake returned an error; fail the future immediately.
65            MidHandshake::Error { io, error } => return Poll::Ready(Err((error, io))),
66            _ => panic!("unexpected polling after handshake"),
67        };
68
69        if !stream.skip_handshake() {
70            let (state, io, session) = stream.get_mut();
71            let mut tls_stream = Stream::new(io, session).set_eof(!state.readable());
72
73            macro_rules! try_poll {
74                ( $e:expr ) => {
75                    match $e {
76                        Poll::Ready(Ok(_)) => (),
77                        Poll::Ready(Err(err)) => return Poll::Ready(Err((err, stream.into_io()))),
78                        Poll::Pending => {
79                            *this = MidHandshake::Handshaking(stream);
80                            return Poll::Pending;
81                        }
82                    }
83                };
84            }
85
86            while tls_stream.session.is_handshaking() {
87                try_poll!(tls_stream.handshake(cx));
88            }
89
90            try_poll!(Pin::new(&mut tls_stream).poll_flush(cx));
91        }
92
93        Poll::Ready(Ok(stream))
94    }
95}
tokio_rustls/common/handshake.rs

tokio_rustls/common/
handshake.rs
