diff --git a/src/relay/tcprelay/crypto_io.rs b/src/relay/tcprelay/crypto_io.rs
new file mode 100644
index 00000000..c4403649
--- /dev/null
+++ b/src/relay/tcprelay/crypto_io.rs
@@ -0,0 +1,319 @@
+//! IO facilities for TCP relay
+
+use std::io::{self, Read, BufRead};
+use std::mem;
+use std::time::Duration;
+
+use futures::{Future, Poll, Async};
+
+use tokio_core::reactor::{Handle, Timeout};
+
+use super::BUFFER_SIZE;
+
+pub trait DecryptedRead: BufRead {}
+
+pub trait EncryptedWrite: Sized {
+    /// Writes raw bytes directly to the writer directly
+    fn write_raw(&mut self, data: &[u8]) -> io::Result<usize>;
+    /// Flush the writer
+    fn flush(&mut self) -> io::Result<()>;
+    /// Encrypt data into buffer for writing
+    fn encrypt(&mut self, data: &[u8], buf: &mut Vec<u8>) -> io::Result<()>;
+
+    /// Encrypt data in `buf` and write all to the writer
+    fn write_all<B: AsRef<[u8]>>(self, buf: B) -> EncryptedWriteAll<Self, B> {
+        EncryptedWriteAll::Writing {
+            writer: self,
+            buf: buf,
+            pos: 0,
+            enc_buf: Vec::new(),
+            encrypted: false,
+        }
+    }
+
+    /// Copies all data from `r`
+    fn copy<R: Read>(self, r: R) -> EncryptedCopy<R, Self> {
+        EncryptedCopy {
+            reader: r,
+            writer: self,
+            read_done: false,
+            amt: 0,
+            pos: 0,
+            cap: 0,
+            buf: Vec::new(),
+        }
+    }
+
+    /// Copies all data from `r` with timeout
+    fn copy_timeout<R: Read>(self, r: R, timeout: Duration, handle: Handle) -> EncryptedCopyTimeout<R, Self> {
+        EncryptedCopyTimeout::new(r, self, timeout, handle)
+    }
+
+    /// Copies all data from `r` with optional timeout
+    fn copy_timeout_opt<R: Read>(self, r: R, timeout: Option<Duration>, handle: Handle) -> EncryptedCopyOpt<R, Self> {
+        match timeout {
+            Some(t) => EncryptedCopyOpt::CopyTimeout(self.copy_timeout(r, t, handle)),
+            None => EncryptedCopyOpt::Copy(self.copy(r)),
+        }
+    }
+}
+
+/// write_all and encrypt data
+pub enum EncryptedWriteAll<W, B>
+    where W: EncryptedWrite,
+          B: AsRef<[u8]>
+{
+    Writing {
+        writer: W,
+        buf: B,
+        pos: usize,
+        enc_buf: Vec<u8>,
+        encrypted: bool,
+    },
+    Empty,
+}
+
+impl<W, B> Future for EncryptedWriteAll<W, B>
+    where W: EncryptedWrite,
+          B: AsRef<[u8]>
+{
+    type Item = (W, B);
+    type Error = io::Error;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match *self {
+            EncryptedWriteAll::Empty => panic!("poll after EncryptedWriteAll finished"),
+            EncryptedWriteAll::Writing { ref mut writer, ref buf, ref mut pos, ref mut enc_buf, ref mut encrypted } => {
+                if !*encrypted {
+                    *encrypted = true;
+                    writer.encrypt(buf.as_ref(), enc_buf)?;
+                }
+
+                while *pos < enc_buf.len() {
+                    let n = try_nb!(writer.write_raw(&enc_buf[*pos..]));
+                    *pos += n;
+                    if n == 0 {
+                        let err = io::Error::new(io::ErrorKind::Other, "zero-length write");
+                        return Err(err);
+                    }
+                }
+            }
+        }
+
+        match mem::replace(self, EncryptedWriteAll::Empty) {
+            EncryptedWriteAll::Writing { writer, buf, .. } => Ok((writer, buf).into()),
+            EncryptedWriteAll::Empty => unreachable!(),
+        }
+    }
+}
+
+/// Encrypted copy
+pub struct EncryptedCopy<R: Read, W: EncryptedWrite> {
+    reader: R,
+    writer: W,
+    read_done: bool,
+    amt: u64,
+    pos: usize,
+    cap: usize,
+    buf: Vec<u8>,
+}
+
+impl<R: Read, W: EncryptedWrite> Future for EncryptedCopy<R, W> {
+    type Item = u64;
+    type Error = io::Error;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        let mut local_buf = [0u8; BUFFER_SIZE];
+        loop {
+            // If our buffer is empty, then we need to read some data to
+            // continue.
+            if self.pos == self.cap && !self.read_done {
+                let n = try_nb!(self.reader.read(&mut local_buf[..]));
+                self.buf.clear();
+                if n == 0 {
+                    self.read_done = true;
+                } else {
+                    self.writer.encrypt(&local_buf[..n], &mut self.buf)?;
+                }
+                self.pos = 0;
+                self.cap = self.buf.len();
+            }
+
+            // If our buffer has some data, let's write it out!
+            while self.pos < self.cap {
+                let i = try_nb!(self.writer.write_raw(&self.buf[self.pos..self.cap]));
+                self.pos += i;
+                self.amt += i as u64;
+            }
+
+            // If we've written al the data and we've seen EOF, flush out the
+            // data and finish the transfer.
+            // done with the entire transfer.
+            if self.pos == self.cap && self.read_done {
+                try_nb!(self.writer.flush());
+                return Ok(self.amt.into());
+            }
+        }
+    }
+}
+
+/// Encrypted copy
+pub struct EncryptedCopyTimeout<R: Read, W: EncryptedWrite> {
+    reader: R,
+    writer: W,
+    read_done: bool,
+    amt: u64,
+    pos: usize,
+    cap: usize,
+    timeout: Duration,
+    handle: Handle,
+    timer: Option<Timeout>,
+    read_buf: [u8; BUFFER_SIZE],
+    write_buf: Vec<u8>,
+}
+
+impl<R: Read, W: EncryptedWrite> EncryptedCopyTimeout<R, W> {
+    fn new(r: R, w: W, dur: Duration, handle: Handle) -> EncryptedCopyTimeout<R, W> {
+        EncryptedCopyTimeout {
+            reader: r,
+            writer: w,
+            read_done: false,
+            amt: 0,
+            pos: 0,
+            cap: 0,
+            timeout: dur,
+            handle: handle,
+            timer: None,
+            read_buf: [0u8; BUFFER_SIZE],
+            write_buf: Vec::new(),
+        }
+    }
+
+    fn try_poll_timeout(&mut self) -> io::Result<()> {
+        match self.timer.as_mut() {
+            None => Ok(()),
+            Some(t) => {
+                match t.poll() {
+                    Err(err) => Err(err),
+                    Ok(Async::Ready(..)) => Err(io::Error::new(io::ErrorKind::TimedOut, "timeout")),
+                    Ok(Async::NotReady) => Ok(()),
+                }
+            }
+        }
+    }
+
+    fn clear_timer(&mut self) {
+        let _ = self.timer.take();
+    }
+
+    fn read_or_set_timeout(&mut self) -> io::Result<usize> {
+        // First, return if timeout
+        try!(self.try_poll_timeout());
+
+        // Then, unset the previous timeout
+        self.clear_timer();
+
+        self.write_buf.clear();
+        match self.reader.read(&mut self.read_buf) {
+            Ok(0) => {
+                self.cap = 0;
+                self.pos = 0;
+                Ok(0)
+            }
+            Ok(n) => {
+                self.writer.encrypt(&self.read_buf[..n], &mut self.write_buf)?;
+                self.cap = self.write_buf.len();
+                self.pos = 0;
+                Ok(n)
+            }
+            Err(e) => {
+                if e.kind() == io::ErrorKind::WouldBlock {
+                    self.timer = Some(Timeout::new(self.timeout, &self.handle).unwrap());
+                }
+                return Err(e);
+            }
+        }
+    }
+
+    fn write_or_set_timeout(&mut self) -> io::Result<usize> {
+        // First, return if timeout
+        try!(self.try_poll_timeout());
+
+        // Then, unset the previous timeout
+        self.clear_timer();
+
+        match self.writer.write_raw(&self.write_buf[self.pos..self.cap]) {
+            Ok(n) => {
+                self.pos += n;
+                Ok(n)
+            }
+            Err(e) => {
+                if e.kind() == io::ErrorKind::WouldBlock {
+                    self.timer = Some(Timeout::new(self.timeout, &self.handle).unwrap());
+                }
+                return Err(e);
+            }
+        }
+    }
+}
+
+impl<R: Read, W: EncryptedWrite> Future for EncryptedCopyTimeout<R, W> {
+    type Item = u64;
+    type Error = io::Error;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+
+        loop {
+            // If our buffer is empty, then we need to read some data to
+            // continue.
+            if self.pos == self.cap && !self.read_done {
+                let n = try_nb!(self.read_or_set_timeout());
+                if n == 0 {
+                    self.read_done = true;
+                }
+            }
+
+            // If our buffer has some data, let's write it out!
+            while self.pos < self.cap {
+                let i = try_nb!(self.write_or_set_timeout());
+                if i == 0 {
+                    let err = io::Error::new(io::ErrorKind::UnexpectedEof, "early eof");
+                    return Err(err);
+                }
+                self.amt += i as u64;
+            }
+
+            // If we've written al the data and we've seen EOF, flush out the
+            // data and finish the transfer.
+            // done with the entire transfer.
+            if self.pos == self.cap && self.read_done {
+                try_nb!(self.writer.flush());
+                return Ok(self.amt.into());
+            }
+        }
+    }
+}
+
+/// Work for both timeout or no timeout
+pub enum EncryptedCopyOpt<R, W>
+    where R: Read,
+          W: EncryptedWrite
+{
+    Copy(EncryptedCopy<R, W>),
+    CopyTimeout(EncryptedCopyTimeout<R, W>),
+}
+
+impl<R, W> Future for EncryptedCopyOpt<R, W>
+    where R: Read,
+          W: EncryptedWrite
+{
+    type Item = u64;
+    type Error = io::Error;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match *self {
+            EncryptedCopyOpt::Copy(ref mut c) => c.poll(),
+            EncryptedCopyOpt::CopyTimeout(ref mut c) => c.poll(),
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/relay/tcprelay/mod.rs b/src/relay/tcprelay/mod.rs
index 6ecd2d0d..8846dee8 100644
--- a/src/relay/tcprelay/mod.rs
+++ b/src/relay/tcprelay/mod.rs
@@ -47,12 +47,14 @@ use net2::TcpBuilder;
 use ip::IpAddr;
 
 use self::stream::{EncryptedWriter, DecryptedReader};
+pub use self::crypto_io::{DecryptedRead, EncryptedWrite};
 
 pub mod local;
 mod socks5_local;
 pub mod server;
 mod stream;
 pub mod client;
+mod crypto_io;
 
 const BUFFER_SIZE: usize = 32 * 1024; // 32K buffer
 
@@ -111,7 +113,7 @@ pub fn proxy_server_handshake(remote_stream: TcpStream,
             // Send relay address to remote
             let local_buf = Vec::new();
             relay_addr.write_to(local_buf)
-                .and_then(move |buf| try_timeout(enc_w.write_all_encrypted(buf), timeout, &handle))
+                .and_then(move |buf| try_timeout(enc_w.write_all(buf), timeout, &handle))
                 .map(|(w, _)| w)
         });
 
diff --git a/src/relay/tcprelay/server.rs b/src/relay/tcprelay/server.rs
index 53024ca3..0bda2289 100644
--- a/src/relay/tcprelay/server.rs
+++ b/src/relay/tcprelay/server.rs
@@ -32,6 +32,7 @@ use config::{Config, ServerConfig};
 use relay::socks5::Address;
 use relay::{BoxIoFuture, boxed_future};
 use relay::dns_resolver::DnsResolver;
+use relay::tcprelay::crypto_io::EncryptedWrite;
 
 use futures::{self, Future};
 use futures::stream::Stream;
@@ -187,7 +188,7 @@ impl TcpRelayClientConnected {
         let handle = self.handle.clone();
         tunnel(self.addr,
                copy_timeout(r, svr_w, self.timeout, self.handle),
-               w_fut.and_then(move |w| w.copy_from_encrypted_timeout(svr_r, timeout, handle)))
+               w_fut.and_then(move |w| w.copy_timeout_opt(svr_r, timeout, handle)))
     }
 }
 
diff --git a/src/relay/tcprelay/socks5_local.rs b/src/relay/tcprelay/socks5_local.rs
index 8db383bf..867becf0 100644
--- a/src/relay/tcprelay/socks5_local.rs
+++ b/src/relay/tcprelay/socks5_local.rs
@@ -43,6 +43,7 @@ use relay::socks5::{TcpRequestHeader, TcpResponseHeader};
 use relay::loadbalancing::server::RoundRobin;
 use relay::loadbalancing::server::LoadBalancer;
 use relay::{BoxIoFuture, boxed_future};
+use relay::tcprelay::crypto_io::EncryptedWrite;
 
 use super::{tunnel, ignore_until_end, try_timeout};
 
@@ -86,8 +87,7 @@ fn handle_socks5_connect(handle: &Handle,
                 let cloned_timeout = timeout.clone();
 
                 let rhalf = svr_r.and_then(move |svr_r| super::copy_timeout(svr_r, w, timeout, handle));
-                let whalf =
-                    svr_w.and_then(move |svr_w| svr_w.copy_from_encrypted_timeout(r, cloned_timeout, cloned_handle));
+                let whalf = svr_w.and_then(move |svr_w| svr_w.copy_timeout_opt(r, cloned_timeout, cloned_handle));
 
                 tunnel(cloned_addr, whalf, rhalf)
             })
diff --git a/src/relay/tcprelay/stream.rs b/src/relay/tcprelay/stream.rs
index 1d2067c5..377ea2cb 100644
--- a/src/relay/tcprelay/stream.rs
+++ b/src/relay/tcprelay/stream.rs
@@ -19,20 +19,13 @@
 // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#![allow(dead_code)]
-
 use std::io::{self, Read, BufRead, Write};
-use std::mem;
 use std::cmp;
-use std::time::Duration;
 
 use crypto::{Cipher, CipherVariant};
 
-use futures::{Future, Poll, Async};
-
-use tokio_core::reactor::{Handle, Timeout};
-
-use super::{BUFFER_SIZE, BoxIoFuture, boxed_future};
+use super::BUFFER_SIZE;
+use super::{EncryptedWrite, DecryptedRead};
 
 /// Reader wrapper that will decrypt data automatically
 pub struct DecryptedReader<R>
@@ -132,6 +125,8 @@ impl<R> Read for DecryptedReader<R>
     }
 }
 
+impl<R> DecryptedRead for DecryptedReader<R> where R: Read {}
+
 /// Writer wrapper that will encrypt data automatically
 pub struct EncryptedWriter<W>
     where W: Write
@@ -151,62 +146,13 @@ impl<W> EncryptedWriter<W>
         }
     }
 
-    #[doc(hidden)]
-    pub fn cipher_update(&mut self, data: &[u8], buf: &mut Vec<u8>) -> io::Result<()> {
+    fn cipher_update(&mut self, data: &[u8], buf: &mut Vec<u8>) -> io::Result<()> {
         self.cipher.update(data, buf).map_err(From::from)
     }
 
     fn cipher_finalize(&mut self, buf: &mut Vec<u8>) -> io::Result<()> {
         self.cipher.finalize(buf).map_err(From::from)
     }
-
-    /// write_all
-    pub fn write_all_encrypted<B: AsRef<[u8]>>(self, buf: B) -> EncryptedWriteAll<W, B> {
-        EncryptedWriteAll::Writing {
-            writer: self,
-            buf: buf,
-            pos: 0,
-            enc_buf: Vec::new(),
-            encrypted: false,
-        }
-    }
-
-    /// Copy all data from reader
-    pub fn copy_from_encrypted<R: Read>(self, r: R) -> EncryptedCopy<R, W> {
-        EncryptedCopy {
-            reader: r,
-            writer: self,
-            read_done: false,
-            amt: 0,
-            pos: 0,
-            cap: 0,
-            buf: Vec::new(),
-        }
-    }
-
-    /// Write raw bytes
-    pub fn write_raw(&mut self, data: &[u8]) -> io::Result<usize> {
-        self.writer.write(data)
-    }
-
-    /// Flush data
-    pub fn flush(&mut self) -> io::Result<()> {
-        self.writer.flush()
-    }
-}
-
-impl<W> EncryptedWriter<W>
-    where W: Write + 'static
-{
-    /// Copy all data from reader with timeout
-    pub fn copy_from_encrypted_timeout<R>(self, r: R, timeout: Option<Duration>, handle: Handle) -> BoxIoFuture<u64>
-        where R: Read + 'static
-    {
-        match timeout {
-            Some(timeout) => boxed_future(EncryptedCopyTimeout::new(r, self, timeout, handle)),
-            None => boxed_future(self.copy_from_encrypted(r)),
-        }
-    }
 }
 
 impl<W> Drop for EncryptedWriter<W>
@@ -222,238 +168,18 @@ impl<W> Drop for EncryptedWriter<W>
     }
 }
 
-/// write_all and encrypt data
-pub enum EncryptedWriteAll<W, B>
-    where W: Write,
-          B: AsRef<[u8]>
+impl<W> EncryptedWrite for EncryptedWriter<W>
+    where W: Write
 {
-    Writing {
-        writer: EncryptedWriter<W>,
-        buf: B,
-        pos: usize,
-        enc_buf: Vec<u8>,
-        encrypted: bool,
-    },
-    Empty,
-}
-
-impl<W, B> Future for EncryptedWriteAll<W, B>
-    where W: Write,
-          B: AsRef<[u8]>
-{
-    type Item = (EncryptedWriter<W>, B);
-    type Error = io::Error;
-
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
-        match *self {
-            EncryptedWriteAll::Empty => panic!("poll after EncryptedWriteAll finished"),
-            EncryptedWriteAll::Writing { ref mut writer, ref buf, ref mut pos, ref mut enc_buf, ref mut encrypted } => {
-                if !*encrypted {
-                    *encrypted = true;
-                    try!(writer.cipher_update(buf.as_ref(), enc_buf));
-                }
-
-                while *pos < enc_buf.len() {
-                    let n = try_nb!(writer.write_raw(&enc_buf[*pos..]));
-                    *pos += n;
-                    if n == 0 {
-                        let err = io::Error::new(io::ErrorKind::Other, "zero-length write");
-                        return Err(err);
-                    }
-                }
-            }
-        }
-
-        match mem::replace(self, EncryptedWriteAll::Empty) {
-            EncryptedWriteAll::Writing { writer, buf, .. } => Ok((writer, buf).into()),
-            EncryptedWriteAll::Empty => unreachable!(),
-        }
-    }
-}
-
-/// Encrypted copy
-pub struct EncryptedCopy<R: Read, W: Write> {
-    reader: R,
-    writer: EncryptedWriter<W>,
-    read_done: bool,
-    amt: u64,
-    pos: usize,
-    cap: usize,
-    buf: Vec<u8>,
-}
-
-impl<R: Read, W: Write> Future for EncryptedCopy<R, W> {
-    type Item = u64;
-    type Error = io::Error;
-
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
-        let mut local_buf = [0u8; BUFFER_SIZE];
-        loop {
-            // If our buffer is empty, then we need to read some data to
-            // continue.
-            if self.pos == self.cap && !self.read_done {
-                let n = try_nb!(self.reader.read(&mut local_buf[..]));
-                self.buf.clear();
-                if n == 0 {
-                    self.read_done = true;
-                } else {
-                    try!(self.writer.cipher_update(&local_buf[..n], &mut self.buf));
-                }
-                self.pos = 0;
-                self.cap = self.buf.len();
-            }
-
-            // If our buffer has some data, let's write it out!
-            while self.pos < self.cap {
-                let i = try_nb!(self.writer.write_raw(&self.buf[self.pos..self.cap]));
-                self.pos += i;
-                self.amt += i as u64;
-            }
-
-            // If we've written al the data and we've seen EOF, flush out the
-            // data and finish the transfer.
-            // done with the entire transfer.
-            if self.pos == self.cap && self.read_done {
-                try_nb!(self.writer.flush());
-                return Ok(self.amt.into());
-            }
-        }
-    }
-}
-
-/// Encrypted copy
-pub struct EncryptedCopyTimeout<R: Read, W: Write> {
-    reader: R,
-    writer: EncryptedWriter<W>,
-    read_done: bool,
-    amt: u64,
-    pos: usize,
-    cap: usize,
-    timeout: Duration,
-    handle: Handle,
-    timer: Option<Timeout>,
-    read_buf: [u8; BUFFER_SIZE],
-    write_buf: Vec<u8>,
-}
-
-impl<R: Read, W: Write> EncryptedCopyTimeout<R, W> {
-    fn new(r: R, w: EncryptedWriter<W>, dur: Duration, handle: Handle) -> EncryptedCopyTimeout<R, W> {
-        EncryptedCopyTimeout {
-            reader: r,
-            writer: w,
-            read_done: false,
-            amt: 0,
-            pos: 0,
-            cap: 0,
-            timeout: dur,
-            handle: handle,
-            timer: None,
-            read_buf: [0u8; BUFFER_SIZE],
-            write_buf: Vec::new(),
-        }
+    fn write_raw(&mut self, data: &[u8]) -> io::Result<usize> {
+        self.writer.write(data)
     }
 
-    fn try_poll_timeout(&mut self) -> io::Result<()> {
-        match self.timer.as_mut() {
-            None => Ok(()),
-            Some(t) => {
-                match t.poll() {
-                    Err(err) => Err(err),
-                    Ok(Async::Ready(..)) => Err(io::Error::new(io::ErrorKind::TimedOut, "timeout")),
-                    Ok(Async::NotReady) => Ok(()),
-                }
-            }
-        }
+    fn flush(&mut self) -> io::Result<()> {
+        self.writer.flush()
     }
 
-    fn clear_timer(&mut self) {
-        let _ = self.timer.take();
-    }
-
-    fn read_or_set_timeout(&mut self) -> io::Result<usize> {
-        // First, return if timeout
-        try!(self.try_poll_timeout());
-
-        // Then, unset the previous timeout
-        self.clear_timer();
-
-        self.write_buf.clear();
-        match self.reader.read(&mut self.read_buf) {
-            Ok(0) => {
-                self.cap = 0;
-                self.pos = 0;
-                Ok(0)
-            }
-            Ok(n) => {
-                self.writer.cipher_update(&self.read_buf[..n], &mut self.write_buf)?;
-                self.cap = self.write_buf.len();
-                self.pos = 0;
-                Ok(n)
-            }
-            Err(e) => {
-                if e.kind() == io::ErrorKind::WouldBlock {
-                    self.timer = Some(Timeout::new(self.timeout, &self.handle).unwrap());
-                }
-                return Err(e);
-            }
-        }
-    }
-
-    fn write_or_set_timeout(&mut self) -> io::Result<usize> {
-        // First, return if timeout
-        try!(self.try_poll_timeout());
-
-        // Then, unset the previous timeout
-        self.clear_timer();
-
-        match self.writer.write_raw(&self.write_buf[self.pos..self.cap]) {
-            Ok(n) => {
-                self.pos += n;
-                Ok(n)
-            }
-            Err(e) => {
-                if e.kind() == io::ErrorKind::WouldBlock {
-                    self.timer = Some(Timeout::new(self.timeout, &self.handle).unwrap());
-                }
-                return Err(e);
-            }
-        }
-    }
-}
-
-impl<R: Read, W: Write> Future for EncryptedCopyTimeout<R, W> {
-    type Item = u64;
-    type Error = io::Error;
-
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
-
-        loop {
-            // If our buffer is empty, then we need to read some data to
-            // continue.
-            if self.pos == self.cap && !self.read_done {
-                let n = try_nb!(self.read_or_set_timeout());
-                if n == 0 {
-                    self.read_done = true;
-                }
-            }
-
-            // If our buffer has some data, let's write it out!
-            while self.pos < self.cap {
-                let i = try_nb!(self.write_or_set_timeout());
-                if i == 0 {
-                    let err = io::Error::new(io::ErrorKind::UnexpectedEof, "early eof");
-                    return Err(err);
-                }
-                self.amt += i as u64;
-            }
-
-            // If we've written al the data and we've seen EOF, flush out the
-            // data and finish the transfer.
-            // done with the entire transfer.
-            if self.pos == self.cap && self.read_done {
-                try_nb!(self.writer.flush());
-                return Ok(self.amt.into());
-            }
-        }
+    fn encrypt(&mut self, data: &[u8], buf: &mut Vec<u8>) -> io::Result<()> {
+        self.cipher_update(data, buf)
     }
 }
\ No newline at end of file