Fix: window size was not respected, resulting in flooding and poor TCP performance

Ignore-this: 1eb49b5fe7b8114406e4669b79b6ecc7

darcs-hash:1821a5827431e9b5ac13e8aa42d43867a4541421

Author: pe

src/client/mod.rs

@@ -496,9 +496,7 @@ impl<H: Handler> Connection<H> {
     }
 
     /// Process all packets available in the buffer, and returns
-    /// whether at least one complete packet was read.  `buffer` and
-    /// `buffer2` are work spaces mostly used to compute keys. They
-    /// are cleared before using, hence nothing is expected from them.
+    /// whether the connection should continue.
     fn atomic_poll(&mut self) -> Poll<bool, HandlerError<H::Error>> {
 
         try_ready!(self.pending_poll());

src/server/mod.rs

@@ -79,8 +79,8 @@ impl Default for Config {
             auth_banner: None,
             auth_rejection_time: std::time::Duration::from_secs(1),
             keys: Vec::new(),
-            window_size: 1 << 30,
-            maximum_packet_size: 1 << 20,
+            window_size: 200000,
+            maximum_packet_size: 200000,
             limits: Limits::default(),
             preferred: Default::default(),
             max_auth_attempts: 10,

src/session.rs

@@ -228,7 +228,7 @@ impl Encrypted {
             };
             let buf_len = buf.len();
 
-            while buf.len() > 0 && channel.recipient_window_size > 0 {
+            while buf.len() > 0 {
                 // Compute the length we're allowed to send.
                 let off = std::cmp::min(buf.len(), channel.recipient_maximum_packet_size as usize);
                 let off = std::cmp::min(off, channel.recipient_window_size as usize);
@@ -247,6 +247,7 @@ impl Encrypted {
                 channel.recipient_window_size -= off as u32;
                 buf = &buf[off..]
             }
+            debug!("buf.len() = {:?}, buf_len = {:?}", buf.len(), buf_len);
             Ok(buf_len)
         } else {
             Err(Error::WrongChannel)