1 files changed, 79 insertions, 0 deletions
diff --git a/source3/lib/arc4.c b/source3/lib/arc4.c
new file mode 100644
index 0000000000..af2564b6c0
--- /dev/null
+++ b/source3/lib/arc4.c
@@ -0,0 +1,79 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   An implementation of arc4.
+
+   Copyright (C) Jeremy Allison 2005.
+   
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+/*****************************************************************
+ Initialize state for an arc4 crypt/decrpyt.
+ arc4 state is 258 bytes - last 2 bytes are the index bytes.
+*****************************************************************/
+
+void smb_arc4_init(unsigned char arc4_state_out[258], const unsigned char *key, size_t keylen)
+{
+	size_t ind;
+	unsigned char j = 0;
+
+	for (ind = 0; ind < 256; ind++) {
+		arc4_state_out[ind] = (unsigned char)ind;
+	}
+
+	for( ind = 0; ind < 256; ind++) {
+		unsigned char tc;
+
+		j += (arc4_state_out[ind] + key[ind%keylen]);
+
+		tc = arc4_state_out[ind];
+		arc4_state_out[ind] = arc4_state_out[j];
+		arc4_state_out[j] = tc;
+	}
+	arc4_state_out[256] = 0;
+	arc4_state_out[257] = 0;
+}
+
+/*****************************************************************
+ Do the arc4 crypt/decrpyt.
+ arc4 state is 258 bytes - last 2 bytes are the index bytes.
+*****************************************************************/
+
+void smb_arc4_crypt(unsigned char arc4_state_inout[258], unsigned char *data, size_t len)
+{
+	unsigned char index_i = arc4_state_inout[256];
+	unsigned char index_j = arc4_state_inout[257];
+        size_t ind;
+
+	for( ind = 0; ind < len; ind++) {
+		unsigned char tc;
+		unsigned char t;
+
+		index_i++;
+		index_j += arc4_state_inout[index_i];
+
+		tc = arc4_state_inout[index_i];
+		arc4_state_inout[index_i] = arc4_state_inout[index_j];
+		arc4_state_inout[index_j] = tc;
+
+		t = arc4_state_inout[index_i] + arc4_state_inout[index_j];
+		data[ind] = data[ind] ^ arc4_state_inout[t];
+	}
+
+	arc4_state_inout[256] = index_i;
+	arc4_state_inout[257] = index_j;
+}