diff -Naur pycrypto-2.0.1.org/src/ARC2.c pycrypto-2.0.1/src/ARC2.c
--- pycrypto-2.0.1.org/src/ARC2.c 2009-02-13 17:08:30.000000000 +0100
+++ pycrypto-2.0.1/src/ARC2.c 2009-02-13 17:08:47.000000000 +0100
@@ -11,6 +11,7 @@
*/
#include <string.h>
+#include "Python.h"
#define MODULE_NAME ARC2
#define BLOCK_SIZE 8
@@ -146,6 +147,12 @@
We'll hardwire it to 1024. */
#define bits 1024
+ if ((U32)keylength > sizeof(self->xkey)) {
+ PyErr_SetString(PyExc_ValueError,
+ "ARC2 key length must be less than 128 bytes");
+ return;
+ }
+
memcpy(self->xkey, key, keylength);
/* Phase 1: Expand input key to 128 bytes */