eh, idk if this is getting anywhere

src/crypt.rs

@@ -5,3 +5,8 @@ pub type RsaPrivateKey = ();
 
 /// TODO: RSA public key
 pub type RsaPublicKey = ();
+
+pub(crate) fn generate() -> RsaPrivateKey
+{
+    todo!()
+}

src/stream.rs

@@ -54,9 +54,12 @@ impl<T, U> Split for (T, U)
 	(a, b)
     }
 }
+//TODO: Add trait `SplitRef` for exchange, I guess?
 
 /// Combined Read + Write encryptable async stream.
 ///
+/// The `AsyncRead` and `AsyncWrite` impls of this type forward to the backing impls for `S`.
+///
 /// # Exchange
 /// A combined stream is the only way to exchange pubkeys and enabling the creation of encrypted read/write wrappers on the combined stream or splits.
 #[pin_project]
@@ -67,7 +70,50 @@ pub struct Stream<S>
     #[pin] stream: S,
 }
 
-impl<S: AsyncStream> Split for Stream<S>
+impl<S> Stream<S>
+where S: Split,
+      S::First: AsyncWrite,
+      S::Second: AsyncRead
+{
+    /// Create a new `Stream` from two streams, one implemetor of `AsyncWrite`, and one of `AsyncRead`.
+    pub fn new(tx: S::First, rx: S::Second) -> Self
+    {
+	Self {
+	    meta: EncryptedStreamMeta {
+		them: None,
+		us: crypt::generate(),
+	    },
+	    stream: S::unsplit(tx, rx),
+	}
+    }
+}
+
+impl<S: AsyncStream> Stream<S>
+{
+    /// Create a new `Stream` from an implementor of both `AsyncRead` and `AsyncWrite`.
+    pub fn new_single(stream: S) -> Self
+    {
+	Self {
+	    meta: EncryptedStreamMeta {
+		them: None,
+		us: crypt::generate(),
+	    },
+	    stream,
+	}
+    }
+
+    /// Create a split by cloning `S`.
+    pub fn split_clone(self) -> (WriteHalf<S>, ReadHalf<S>)
+	where S: Clone
+    {
+	Stream {
+	    stream: (self.stream.clone(), self.stream),
+	    meta: self.meta
+	}.split()
+    }
+}
+
+impl<S> Split for Stream<S>
 where S: Split,
       S::First: AsyncWrite,
       S::Second: AsyncRead
@@ -83,7 +129,7 @@ where S: Split,
     }
 }
 
-impl<S: AsyncStream> Stream<S>
+impl<S> Stream<S>
 where S: Split,
       S::First: AsyncWrite,
       S::Second: AsyncRead