Added `bin` module for byte slice concat.

Removed !Unpin `exchange()` function.

Removed `Exchange<"sock,W,R>` future

Tests for RSA ciphertext len passing. (512 bytes static.)

Fortune for rsh's current commit: Future small blessing − 末小吉

Cargo.lock

@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "ad-hoc-iter"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90a8dd76beceb5313687262230fcbaaf8d4e25c37541350cf0932e9adb8309c8"
+
 [[package]]
 name = "addr2line"
 version = "0.16.0"
@@ -106,9 +112,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "chacha20stream"
-version = "2.0.1"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b34f4279658654cc2c7dbb36ba00b620dd5532153a9b9ebfea1b7ef282e1d4"
+checksum = "54c8d48b47fa0a89a94b80d32b1b3fc9ffc1a232a5201ff5a2d14ac77bc7561d"
 dependencies = [
  "base64 0.13.0",
  "getrandom 0.2.3",
@@ -116,6 +122,7 @@ dependencies = [
  "openssl",
  "pin-project",
  "rustc_version",
+ "serde",
  "smallvec",
  "stackalloc",
  "tokio 0.2.25",
@@ -791,6 +798,7 @@ dependencies = [
 name = "rsh"
 version = "0.1.0"
 dependencies = [
+ "ad-hoc-iter",
  "bytes 1.0.1",
  "chacha20stream",
  "color-eyre",

Cargo.toml

@@ -6,8 +6,9 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+ad-hoc-iter = "0.2.3"
 bytes = { version = "1.0.1", features = ["serde"] }
-chacha20stream = { version = "2.0.1", features = ["async"] }
+chacha20stream = { version = "2.1.0", features = ["async", "serde"] }
 color-eyre = "0.5.11"
 cryptohelpers = { version = "1.8.1" , features = ["serialise", "full"] }
 futures = "0.3.16"

src/bin.rs

@@ -0,0 +1,37 @@
+//! Binary / byte maniuplation
+use bytes::BufMut;
+
+/// Concatenate an iterator of byte slices into a buffer.
+///
+/// # Returns
+/// The number of bytes written
+/// # Panics
+/// If the buffer cannot hold all the slices
+pub fn collect_slices_into<B: BufMut + ?Sized, I, T>(into: &mut B, from: I) -> usize
+where I: IntoIterator<Item=T>,
+      T: AsRef<[u8]>
+{
+    let mut done =0;
+    for slice in from.into_iter()
+    {
+	let s = slice.as_ref();
+	into.put_slice(s);
+	done+=s.len();
+    }
+    done
+}
+
+/// Collect an iterator of byte slices into a new exact-size buffer.
+///
+/// # Returns
+/// The number of bytes written, and the new array
+///
+/// # Panics
+/// If the total bytes in all slices exceeds `SIZE`.
+pub fn collect_slices_exact<T, I, const SIZE: usize>(from: I) -> (usize, [u8; SIZE])
+where I: IntoIterator<Item=T>,
+      T: AsRef<[u8]>
+{
+    let mut output = [0u8; SIZE];
+    (collect_slices_into(&mut &mut output[..], from), output)
+}

src/main.rs

@@ -4,6 +4,7 @@
 #![allow(dead_code)]
 
 #[macro_use] extern crate serde;
+#[macro_use] extern crate ad_hoc_iter;
 #[macro_use] extern crate pin_project;
 
 #[allow(unused_imports)]
@@ -21,6 +22,7 @@ use std::convert::{
 };
 
 mod ext; use ext::*;
+mod bin;
 mod message;
 
 mod cancel;
@@ -30,8 +32,8 @@ mod sock;
 //mod pipeline;
 
 #[tokio::main]
-async fn main() -> eyre::Result<()> {
+async fn main() -> eyre::Result<()>
-    println!("Hello, world!");
+{
-    
+
     Ok(())
 }

src/sock/enc.rs

@@ -10,11 +10,15 @@ use cryptohelpers::{
 use chacha20stream::{
     AsyncSink,
     AsyncSource,
+
+    Key, IV,
 };
 use std::sync::Arc;
 use tokio::{
     sync::{
 	RwLock,
+	RwLockReadGuard,
+	RwLockWriteGuard,
     },
     io::{
 	DuplexStream,
@@ -26,9 +30,15 @@ use std::{
 	Context, Poll,
     },
     pin::Pin,
-    marker::Unpin,
+    marker::{
+	Unpin,
+	PhantomPinned,
+    },
 };
 
+/// Size of a single RSA ciphertext.
+pub const RSA_CIPHERTEXT_SIZE: usize = 512;
+
 /// Max size to read when exchanging keys
 const TRANS_KEY_MAX_SIZE: usize = 4096;
 
@@ -39,12 +49,28 @@ struct ESockInfo {
     them: Option<RsaPublicKey>,
 }
 
+#[derive(Debug)]
+struct ESockState {
+    encr: bool,
+    encw: bool,
+}
+
+/// Contains a Key and IV that can be serialized and then encrypted
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+struct ESockSessionKey
+{
+    key: Key,
+    iv: IV,
+}
+
 /// A tx+rx socket.
 #[pin_project]
 #[derive(Debug)]
 pub struct ESock<W, R> {
-    info: RwLock<ESockInfo>,
+    info: ESockInfo,
 
+    state: ESockState,
+    
     #[pin]
     rx: AsyncSource<R>,
     #[pin]
@@ -64,19 +90,84 @@ impl<W: AsyncWrite, R: AsyncRead> ESock<W, R>
     }
 
     /// Create a future that exchanges keys
-    pub fn exchange(&mut self) -> Exchange<'_, W, R>
+    pub fn exchange_unsafe(&mut self) -> Exchange<'_, W, R>
     {
-	Exchange{sock: self}
+	let us = self.info.us.get_public_parts();
+	todo!("Currently unimplemented")
+	/*
+	    Exchange{
+	    sock: self,
+	    write_buf: Default::default(),
+	    read_buf: Default::default(),
+	    _pin: PhantomPinned,
+
+	    read_state: Default::default(),
+	    write_state: Default::default(),
+
+	    us,
+	    them: None,
+	    us_written: Default::default(),
+	    us_buf: (),
+	    write_sz_num: (),
+	    write_sz_buf: (),
+	    read_sz_buf: (),
+    }*/
+    }
+
+    ///Get a mutable ref to unencrypted read+write
+    fn unencrypted(&mut self) -> (&mut W, &mut R)
+    {
+	(self.tx.inner_mut(), self.rx.inner_mut())
+    }
+    /// Get a mutable ref to encrypted write+read
+    fn encrypted(&mut self) -> (&mut AsyncSink<W>, &mut AsyncSource<R>)
+    {
+	(&mut self.tx, &mut self.rx)
+    }
+
+    /// Have the RSA keys been exchanged?
+    pub fn has_exchanged(&self) -> bool
+    {
+	self.info.them.is_some()
+    }
+    
+    /// Is the Write + Read operation encrypted? Tuple is `(Tx, Rx)`.
+    pub fn is_encrypted(&self) -> (bool, bool)
+    {
+	(self.state.encw, self.state.encr)
     }
 }
 
 impl<W: AsyncWrite+ Unpin, R: AsyncRead + Unpin> ESock<W, R>
 {
+    /// Enable write encryption
+    pub async fn set_encrypted_write(&mut self, set: bool) -> eyre::Result<()>
+    {
+	if set {
+	    let (key, iv) = ((),());
+	    self.state.encw = true;
+	    Ok(())
+	} else {
+	    self.state.encw = false;
+	    Ok(())
+	}
+    }
+    
+    /// Get dynamic ref to unencrypted write+read
+    fn unencrypted_dyn(&mut self) -> (&mut (dyn AsyncWrite + Unpin + '_), &mut (dyn AsyncRead + Unpin + '_))
+    {
+	(self.tx.inner_mut(), self.rx.inner_mut())
+    }
+    /// Get dynamic ref to encrypted write+read
+    fn encrypted_dyn(&mut self) -> (&mut (dyn AsyncWrite + Unpin + '_), &mut (dyn AsyncRead + Unpin + '_))
+    {
+	(&mut self.tx, &mut self.rx)
+    }
     /// Exchange keys.
-    pub async fn exchange_unpin(&mut self) -> eyre::Result<()>
+    pub async fn exchange(&mut self) -> eyre::Result<()>
     {
 	use tokio::prelude::*;
-	let our_key = self.info.read().await.us.get_public_parts();
+	let our_key = self.info.us.get_public_parts();
 	let (tx, rx) = self.inner_mut();
 	let read_fut = {
 	    
@@ -112,30 +203,172 @@ impl<W: AsyncWrite+ Unpin, R: AsyncRead + Unpin> ESock<W, R>
 	let (send, recv) = tokio::join! [write_fut, read_fut];
 	send?;
 	let recv = recv?;
-	self.info.write().await.them = Some(recv);
+	self.info.them = Some(recv);
 	Ok(())
     }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Copy, PartialOrd, Ord)]
+enum ExchangeState
+{
+    /// We are currently reading/writing the buffer's size
+    BufferSize,
+    /// We are currently reading/writing the buffer itself
+    Buffer,
+}
+
+impl Default for ExchangeState
+{
+    #[inline]
+    fn default() -> Self
+    {
+	Self::BufferSize
+    }
+}
+
+
+#[pin_project]
+#[derive(Debug)]
 pub struct Exchange<'a, W, R>
 {
     sock: &'a mut ESock<W, R>,
+
+    us: RsaPublicKey,
+
+    us_written: usize,
+    us_buf: Vec<u8>,
+    
+    /// The return value
+    them: Option<RsaPublicKey>,
+
+    write_sz_num: usize,
+    write_sz_buf: [u8; std::mem::size_of::<u64>()],
+    read_sz_buf: [u8; std::mem::size_of::<u64>()],
+
+    read_buf: Vec<u8>,
+    
+    write_state: ExchangeState,
+    read_state: ExchangeState,
+
+    #[pin] _pin: PhantomPinned,
 }
 
+/*
 impl<'a, W: AsyncWrite, R: AsyncRead> Future for Exchange<'a, W, R>
 {
-    type Output = eyre::Result<()>;
+type Output = eyre::Result<()>;
-    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+use futures::ready;
+let this = self.project();
+let (tx, rx) = {
+let sock = this.sock;
+//XXX: Idk if this is safe?
+unsafe {
+(Pin::new_unchecked(&mut sock.tx), Pin::new_unchecked(&mut sock.rx))
+	    }
+	};
+
+	if this.us_buf.is_empty() {
+	    *this.us_buf = this.us.to_bytes();
+	}
+	
+	let poll_write = loop {
+	    break match this.write_state {
+		ExchangeState::BufferSize => {
+		    if *this.write_sz_num == 0 {
+			*this.write_sz_buf = u64::try_from(this.us_buf.len())?.to_be_bytes();
+		    }
+		    // Write this to tx.
+		    match tx.poll_write(cx, &this.write_sz_buf[(*this.write_sz_num)..]) {
+			x @ Poll::Ready(Ok(n)) => {
+			    *this.write_sz_num+=n;
+			    if *this.write_sz_num == this.write_sz_buf.len() {
+				// We've written all the size bytes, continue to writing the buffer bytes.
+				*this.write_state = ExchangeState::Buffer;
+				continue;
+			    }
+
+			    x
+			},
+			x => x,
+		    }
+		},
+		ExchangeState::Buffer => {
+		    match tx.poll_write(cx, &this.us_buf[(*this.us_written)..]) {
+			x @ Poll::Ready(Ok(n)) => {
+			    if *this.us_written == this.us.len() {
+				
+			    }
+
+			    x
+			},
+			x=> x,
+		    }
+		},
+	    }
+	};
+	let poll_read = match this.read_state {
+	    ExchangeState::BufferSize => {
+		
+	    },
+	    ExchangeState::Buffer => {
+		
+	    },
+	};
 	todo!("This is going to be dificult to implement... We don't have access to write_all and read_exact")
     }
 }
-
+*/
 /// Write half for `ESock`.
 #[pin_project]
 #[derive(Debug)]
-pub struct ESockWriteHalf<W>(Arc<ESockInfo>, #[pin] AsyncSink<W>);
+pub struct ESockWriteHalf<W>(Arc<(ESockInfo, RwLock<ESockState>)>, #[pin] AsyncSink<W>);
 
 /// Read half for `ESock`.
 #[pin_project]
 #[derive(Debug)]
-pub struct ESockReadHalf<R>(Arc<ESockInfo>, #[pin] AsyncSource<R>);
+pub struct ESockReadHalf<R>(Arc<(ESockInfo, RwLock<ESockState>)>, #[pin] AsyncSource<R>);
+
+#[cfg(test)]
+mod tests
+{
+    #[test]
+    fn rsa_ciphertext_len() -> crate::eyre::Result<()>
+    {
+	let data = {
+	    use chacha20stream::cha::{KEY_SIZE, IV_SIZE};
+	    let (key, iv) = chacha20stream::cha::keygen();
+	    let (sz, d) = crate::bin::collect_slices_exact::<&[u8], _, {KEY_SIZE + IV_SIZE}>([key.as_ref(), iv.as_ref()]);
+	    assert_eq!(sz, d.len());
+	    d
+	};
+	println!("KEY+IV: {} bytes", data.len());
+
+	let key = cryptohelpers::rsa::RsaPublicKey::generate()?;
+	let rsa = cryptohelpers::rsa::encrypt_slice_to_vec(data, &key)?;
+	println!("Rsa ciphertext size: {}", rsa.len());
+
+	assert_eq!(rsa.len(), super::RSA_CIPHERTEXT_SIZE, "Incorrect RSA ciphertext length constant for cc20 KEY+IV encoding.");
+
+	Ok(())
+    }
+    #[test]
+    fn rsa_serial_ciphertext_len() -> crate::eyre::Result<()>
+    {
+	let data = serde_cbor::to_vec(&{
+	    let (key, iv) = chacha20stream::cha::keygen();
+	    super::ESockSessionKey {
+		key, iv,
+	    }
+	}).expect("Failed to CBOR encode Key+IV");
+	println!("(cbor) KEY+IV: {} bytes", data.len());
+
+	let key = cryptohelpers::rsa::RsaPublicKey::generate()?;
+	let rsa = cryptohelpers::rsa::encrypt_slice_to_vec(data, &key)?;
+	println!("Rsa ciphertext size: {}", rsa.len());
+
+	assert_eq!(rsa.len(), super::RSA_CIPHERTEXT_SIZE, "Incorrect RSA ciphertext length constant for cc20 KEY+IV CBOR encoding.");
+
+	Ok(())
+    }
+}