1 files changed, 63 insertions, 0 deletions
diff --git a/contrib/wpa_supplicant/rc4.c b/contrib/wpa_supplicant/rc4.c
new file mode 100644
index 000000000000..97ec1b0ae357
--- /dev/null
+++ b/contrib/wpa_supplicant/rc4.c
@@ -0,0 +1,63 @@
+/*
+ * Host AP (software wireless LAN access point) user space daemon for
+ * Host AP kernel driver / RC4
+ * Copyright (c) 2002-2004, Jouni Malinen <jkmaline@cc.hut.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include <stdio.h>
+#include "common.h"
+#include "rc4.h"
+
+#define S_SWAP(a,b) do { u8 t = S[a]; S[a] = S[b]; S[b] = t; } while(0)
+
+void rc4_skip(u8 *key, size_t keylen, size_t skip, u8 *data, size_t data_len)
+{
+	u32 i, j, k;
+	u8 S[256], *pos;
+	int kpos;
+
+	/* Setup RC4 state */
+	for (i = 0; i < 256; i++)
+		S[i] = i;
+	j = 0;
+	kpos = 0;
+	for (i = 0; i < 256; i++) {
+		j = (j + S[i] + key[kpos]) & 0xff;
+		kpos++;
+		if (kpos >= keylen)
+			kpos = 0;
+		S_SWAP(i, j);
+	}
+
+	/* Skip the start of the stream */
+	i = j = 0;
+	for (k = 0; k < skip; k++) {
+		i = (i + 1) & 0xff;
+		j = (j + S[i]) & 0xff;
+		S_SWAP(i, j);
+	}
+
+	/* Apply RC4 to data */
+	pos = data;
+	for (k = 0; k < data_len; k++) {
+		i = (i + 1) & 0xff;
+		j = (j + S[i]) & 0xff;
+		S_SWAP(i, j);
+		*pos++ ^= S[(S[i] + S[j]) & 0xff];
+	}
+}
+
+
+void rc4(u8 *buf, size_t len, u8 *key, size_t key_len)
+{
+	rc4_skip(key, key_len, 0, buf, len);
+}