From 70448dda08e6f07e837ff9c8d166dc29d15341cd Mon Sep 17 00:00:00 2001
From: Russ Magee <rmagee@gmail.com>
Date: Fri, 4 May 2018 23:31:06 -0700
Subject: [PATCH] No need for custom hkexsh.Copy()

---
 hkexnet.go         | 39 ---------------------------------------
 hkexsh/hkexsh.go   |  2 +-
 hkexshd/hkexshd.go |  5 ++---
 3 files changed, 3 insertions(+), 43 deletions(-)

diff --git a/hkexnet.go b/hkexnet.go
index 05ce922..cb3f4c2 100644
--- a/hkexnet.go
+++ b/hkexnet.go
@@ -530,42 +530,3 @@ func (c *Conn) chaffHelper(szMax int) {
 		}
 	}()
 }
-
-// hkexsh.Copy() is a modified version of io.Copy()
-func Copy(dst io.Writer, src io.Reader) (written int64, err error) {
-	// If the reader has a WriteTo method, use it to do the copy.
-	// Avoids an allocation and a copy.
-	if wt, ok := src.(io.WriterTo); ok {
-		return wt.WriteTo(dst)
-	}
-	// Similarly, if the writer has a ReadFrom method, use it to do the copy.
-	if rt, ok := dst.(io.ReaderFrom); ok {
-		return rt.ReadFrom(src)
-	}
-
-	buf := make([]byte, 32*1024)
-	for {
-		nr, er := src.Read(buf)
-		if nr > 0 {
-			nw, ew := dst.Write(buf[0:nr])
-			if nw > 0 {
-				written += int64(nw)
-			}
-			if ew != nil {
-				err = ew
-				break
-			}
-			if nr != nw {
-				err = io.ErrShortWrite
-				break
-			}
-		}
-		if er != nil {
-			if er != io.EOF {
-				err = er
-			}
-			break
-		}
-	}
-	return written, err
-}
diff --git a/hkexsh/hkexsh.go b/hkexsh/hkexsh.go
index 76a96c7..b0644ac 100644
--- a/hkexsh/hkexsh.go
+++ b/hkexsh/hkexsh.go
@@ -230,7 +230,7 @@ func main() {
 			//!_, outerr := io.Copy(conn, os.Stdin)
 			conn.Chaff(true, 100, 500, 32) // enable client->server chaffing
 			_, outerr := func(conn *hkexsh.Conn, r io.Reader) (w int64, e error) {
-				return hkexsh.Copy(conn, r)
+				return io.Copy(conn, r)
 			}(conn, os.Stdin)
 
 			if outerr != nil {
diff --git a/hkexshd/hkexshd.go b/hkexshd/hkexshd.go
index e33180f..8882510 100644
--- a/hkexshd/hkexshd.go
+++ b/hkexshd/hkexshd.go
@@ -131,7 +131,7 @@ func runShellAs(who string, cmd string, interactive bool, conn hkexsh.Conn) (err
 
 	// Copy stdin to the pty.. (bgnd goroutine)
 	go func() {
-		_, _ = hkexsh.Copy(ptmx, conn)
+		_, _ = io.Copy(ptmx, conn)
 	}()
 
 	// ..and the pty to stdout.
@@ -140,8 +140,7 @@ func runShellAs(who string, cmd string, interactive bool, conn hkexsh.Conn) (err
 	// --knowledge of another thread which would do chaffing.
 	// --Modify pty somehow to slave the command through hkexsh.Copy() ?
 	conn.Chaff(true, 100, 500, 32)
-	_, _ = hkexsh.Copy(conn, ptmx)
-	//_, _ = io.Copy(conn, ptmx)
+	_, _ = io.Copy(conn, ptmx)
 
 	//err = c.Run()  // returns when c finishes.