1 files changed, 87 insertions, 0 deletions
diff --git a/drivers/staging/vt6656/rc4.c b/drivers/staging/vt6656/rc4.c
new file mode 100644
index 00000000000..2fd836f0753
--- /dev/null
+++ b/drivers/staging/vt6656/rc4.c
@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * File: rc4.c
+ *
+ * Purpose:
+ *
+ * Functions:
+ *
+ * Revision History:
+ *
+ * Author: Kyle Hsu
+ *
+ * Date: Sep 4, 2002
+ *
+ */
+
+#include "rc4.h"
+
+void rc4_init(PRC4Ext pRC4, u8 * pbyKey, unsigned int cbKey_len)
+{
+	unsigned int  ust1, ust2;
+	unsigned int  keyindex;
+	unsigned int  stateindex;
+	u8 * pbyst;
+	unsigned int  idx;
+
+	pbyst = pRC4->abystate;
+	pRC4->ux = 0;
+	pRC4->uy = 0;
+	for (idx = 0; idx < 256; idx++)
+		pbyst[idx] = (u8)idx;
+	keyindex = 0;
+	stateindex = 0;
+	for (idx = 0; idx < 256; idx++) {
+		ust1 = pbyst[idx];
+		stateindex = (stateindex + pbyKey[keyindex] + ust1) & 0xff;
+		ust2 = pbyst[stateindex];
+		pbyst[stateindex] = (u8)ust1;
+		pbyst[idx] = (u8)ust2;
+		if (++keyindex >= cbKey_len)
+			keyindex = 0;
+	}
+}
+
+unsigned int rc4_byte(PRC4Ext pRC4)
+{
+	unsigned int ux;
+	unsigned int uy;
+	unsigned int ustx, usty;
+	u8 * pbyst;
+
+	pbyst = pRC4->abystate;
+	ux = (pRC4->ux + 1) & 0xff;
+	ustx = pbyst[ux];
+	uy = (ustx + pRC4->uy) & 0xff;
+	usty = pbyst[uy];
+	pRC4->ux = ux;
+	pRC4->uy = uy;
+	pbyst[uy] = (u8)ustx;
+	pbyst[ux] = (u8)usty;
+
+	return pbyst[(ustx + usty) & 0xff];
+}
+
+void rc4_encrypt(PRC4Ext pRC4, u8 * pbyDest,
+			u8 * pbySrc, unsigned int cbData_len)
+{
+	unsigned int ii;
+	for (ii = 0; ii < cbData_len; ii++)
+		pbyDest[ii] = (u8)(pbySrc[ii] ^ rc4_byte(pRC4));
+}