Refactor cipherrwc to wrappers

wrappers/streamcipherrwc.go

@@ -0,0 +1,53 @@
+package wrappers
+
+import (
+	"bytes"
+	"crypto/cipher"
+	"io"
+)
+
+type StreamCipherReadWriteCloser struct {
+	encryptor cipher.Stream
+	decryptor cipher.Stream
+	conn      io.ReadWriteCloser
+	rest      *bytes.Buffer
+}
+
+// Read reads from connection
+func (c *StreamCipherReadWriteCloser) Read(p []byte) (n int, err error) {
+	n, err = c.conn.Read(p)
+	c.decryptor.XORKeyStream(p, p[:n])
+	return
+}
+
+// Write writes into connection.
+func (c *StreamCipherReadWriteCloser) Write(p []byte) (int, error) {
+	encrypted := make([]byte, len(p))
+	c.encryptor.XORKeyStream(encrypted, p)
+	allWritten := 0
+
+	for len(encrypted) > 0 {
+		n, err := c.conn.Write(encrypted)
+		allWritten += n
+		if err != nil {
+			return allWritten, err
+		}
+		encrypted = encrypted[n:]
+	}
+
+	return allWritten, nil
+}
+
+// Close closes underlying connection.
+func (c *StreamCipherReadWriteCloser) Close() error {
+	return c.conn.Close()
+}
+
+func NewStreamCipherRWC(conn io.ReadWriteCloser, encryptor, decryptor cipher.Stream) io.ReadWriteCloser {
+	return &StreamCipherReadWriteCloser{
+		conn:      conn,
+		encryptor: encryptor,
+		decryptor: decryptor,
+		rest:      &bytes.Buffer{},
+	}
+}