1 files changed, 20 insertions, 0 deletions
diff --git a/libgo/go/crypto/rc4/rc4_ref.go b/libgo/go/crypto/rc4/rc4_ref.go
new file mode 100644
index 0000000..13d52b9
--- /dev/null
+++ b/libgo/go/crypto/rc4/rc4_ref.go
@@ -0,0 +1,20 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !amd64,!arm,!386
+
+package rc4
+
+// XORKeyStream sets dst to the result of XORing src with the key stream.
+// Dst and src may be the same slice but otherwise should not overlap.
+func (c *Cipher) XORKeyStream(dst, src []byte) {
+	i, j := c.i, c.j
+	for k, v := range src {
+		i += 1
+		j += uint8(c.s[i])
+		c.s[i], c.s[j] = c.s[j], c.s[i]
+		dst[k] = v ^ byte(c.s[byte(c.s[i]+c.s[j])])
+	}
+	c.i, c.j = i, j
+}