1 files changed, 89 insertions, 0 deletions
diff --git a/drivers/staging/vt6656/rc4.c b/drivers/staging/vt6656/rc4.c
new file mode 100644
index 000000000000..5ad12a3746c0
--- /dev/null
+++ b/drivers/staging/vt6656/rc4.c
@@ -0,0 +1,89 @@
+/*
+ * 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
+ *
+ */
+
+#if !defined(__RC4_H__)
+#include "rc4.h"
+#endif
+
+VOID rc4_init(PRC4Ext pRC4, PBYTE pbyKey, UINT cbKey_len)
+{
+    UINT  ust1, ust2;
+    UINT  keyindex;
+    UINT  stateindex;
+    PBYTE pbyst;
+    UINT  idx;
+
+    pbyst = pRC4->abystate;
+    pRC4->ux = 0;
+    pRC4->uy = 0;
+    for (idx = 0; idx < 256; idx++)
+        pbyst[idx] = (BYTE)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] = (BYTE)ust1;
+        pbyst[idx] = (BYTE)ust2;
+        if (++keyindex >= cbKey_len)
+            keyindex = 0;
+    }
+}
+
+UINT rc4_byte(PRC4Ext pRC4)
+{
+    UINT ux;
+    UINT uy;
+    UINT ustx, usty;
+    PBYTE 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] = (BYTE)ustx;
+    pbyst[ux] = (BYTE)usty;
+
+    return pbyst[(ustx + usty) & 0xff];
+}
+
+VOID rc4_encrypt(PRC4Ext pRC4, PBYTE pbyDest,
+                     PBYTE pbySrc, UINT cbData_len)
+{
+    UINT ii;
+    for (ii = 0; ii < cbData_len; ii++)
+        pbyDest[ii] = (BYTE)(pbySrc[ii] ^ rc4_byte(pRC4));
+}