1 files changed, 100 insertions, 0 deletions
diff --git a/libktorrent/mse/rc4encryptor.cpp b/libktorrent/mse/rc4encryptor.cpp
new file mode 100644
index 0000000..422fe5d
--- /dev/null
+++ b/libktorrent/mse/rc4encryptor.cpp
@@ -0,0 +1,100 @@
+ /***************************************************************************
+ *   Copyright (C) 2005 by Joris Guisson                                   *
+ *   joris.guisson@gmail.com                                               *
+ *                                                                         *
+ *   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.             *
+ ***************************************************************************/
+#include "rc4encryptor.h"
+
+namespace mse
+{
+	static void swap(Uint8 & a,Uint8 & b)
+	{
+		Uint8 tmp = a;
+		a = b;
+		b = tmp;
+	}
+	
+	static Uint8 rc4_enc_buffer[bt::MAX_MSGLEN];
+	
+	RC4::RC4(const Uint8* key,Uint32 size) : i(0),j(0)
+	{
+		// initialize state
+		for (Uint32 t = 0;t < 256;t++)
+			s[t] = t;
+		
+		j = 0;
+		for (Uint32 t=0;t < 256;t++)
+		{
+			j = (j + s[t] + key[t % size]) & 0xff;
+			swap(s[t],s[j]);
+		}
+		
+		i = j = 0;
+	}
+	
+	RC4::~RC4()
+	{
+	}
+		
+	void RC4::process(const Uint8* in,Uint8* out,Uint32 size)
+	{
+		for (Uint32 k = 0;k < size;k++)
+		{
+			out[k] = process(in[k]);
+		}
+	}
+	
+	Uint8 RC4::process(Uint8 b)
+	{
+		i = (i + 1) & 0xff;
+		j = (j + s[i]) & 0xff;
+		swap(s[i],s[j]);
+		Uint8 tmp = s[ (s[i] + s[j]) & 0xff];
+		return tmp ^ b;
+	}
+	
+
+	RC4Encryptor::RC4Encryptor(const bt::SHA1Hash & dk,const bt::SHA1Hash & ek) 
+	: enc(ek.getData(),20),dec(dk.getData(),20)
+	{
+		Uint8 tmp[1024];
+		enc.process(tmp,tmp,1024);
+		dec.process(tmp,tmp,1024);
+	}
+
+
+	RC4Encryptor::~RC4Encryptor()
+	{}
+
+
+	void RC4Encryptor::decrypt(Uint8* data,Uint32 len)
+	{
+		dec.process(data,data,len);
+	}
+
+	const Uint8* RC4Encryptor::encrypt(const Uint8* data,Uint32 len)
+	{
+		enc.process(data,rc4_enc_buffer,len);
+		return rc4_enc_buffer;
+	}
+	
+	void RC4Encryptor::encryptReplace(Uint8* data,Uint32 len)
+	{
+		enc.process(data,data,len);
+	}
+	
+}