X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/d03ab969116fe715d569304c1c474749b2f64529..c3321b13915e3b839da060f8dc63c68e31bcc360:/rc5.h

diff --git a/rc5.h b/rc5.h
index 23e6080..c029832 100644
--- a/rc5.h
+++ b/rc5.h
@@ -1,13 +1,13 @@
 /* -*-c-*-
  *
- * $Id: rc5.h,v 1.1 1999/09/03 08:41:12 mdw Exp $
+ * $Id: rc5.h,v 1.4 2004/04/08 01:36:15 mdw Exp $
  *
  * The RC5-32/12 block cipher
  *
  * (c) 1999 Straylight/Edgeware
  */
 
-/*----- Licensing notice --------------------------------------------------* 
+/*----- Licensing notice --------------------------------------------------*
  *
  * This file is part of Catacomb.
  *
@@ -15,28 +15,30 @@
  * it under the terms of the GNU Library General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License, or (at your option) any later version.
- * 
+ *
  * Catacomb 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 Library General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Library General Public
  * License along with Catacomb; if not, write to the Free
  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: rc5.h,v $
- * Revision 1.1  1999/09/03 08:41:12  mdw
- * Initial import.
+/*----- Notes on the RC5 block cipher -------------------------------------*
  *
+ * RC5 was designed by Ron Rivest as a test vehicle for the use of data-
+ * dependent rotations in cryptographic transformations.  The algorithm is
+ * covered by a patent held by RSA Security Inc. (US Patent# 5,724,428).
+ * It's vulnerable to some clever differential attacks, which can break it in
+ * about %$2^{44}$% chosen plaintexts.  I don't recommend the use of this
+ * cipher.
  */
 
-#ifndef RC5_H
-#define RC5_H
+#ifndef CATACOMB_RC5_H
+#define CATACOMB_RC5_H
 
 #ifdef __cplusplus
   extern "C" {
@@ -49,10 +51,12 @@
 /*----- Magic numbers -----------------------------------------------------*/
 
 #define RC5_ROUNDS 12
-#define RC5_KEYSZ 0
+#define RC5_KEYSZ 10
 #define RC5_BLKSZ 8
 #define RC5_CLASS (N, L, 64)
 
+extern const octet rc5_keysz[];
+
 /*----- Data structures ---------------------------------------------------*/
 
 typedef struct rc5_ctx {