simple noekeon based prng

diff --git a/noekeon_prng.c b/noekeon_prng.c
new file mode 100644 (file)
index 0000000..4e73c7c
--- /dev/null
+++ b/noekeon_prng.c
@@ -0,0 +1,67 @@
+/* noekeon_prng.c */
+/*
+ *   This file is part of the AVR-Crypto-Lib.
+ *   Copyright (C) 2006, 2007, 2008  Daniel Otte (daniel.otte@rub.de)
+ *
+ *   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/>.
+ */
+/**
+ * \author     Daniel Otte
+ * \date       2008-08-24
+ * \license GPLv3 or later
+ * \brief   random number generator based on noekeon running in CFB-mode
+ * 
+ */
+
+#include "noekeon.h"
+#include "memxor.h"
+#include <stdint.h>
+#include <string.h>
+
+static uint8_t random_state[16];
+static uint8_t random_key[16];
+static uint8_t i=0;
+
+uint8_t random8(void){
+       static uint8_t sr[16];
+       
+       if(i==0){
+               noekeon_enc(random_state, random_key);
+               memcpy(sr, random_state, 16);
+               i=15;
+               return sr[15];
+       }
+       --i;
+       return sr[i];
+}
+
+void random_block(void* dest){
+       i=0;
+       noekeon_enc(random_state, random_key);
+       memcpy(dest, random_state, 16);
+}
+
+void srandom32(uint32_t seed){
+       memcpy(random_key, &seed, 4);
+}
+
+void random_seed(const void* buffer){
+       memcpy(random_key, buffer, 16);
+}
+
+void random_add(const void* buffer){
+       memxor(random_key, buffer, 16);
+}
+
+

diff --git a/noekeon_prng.h b/noekeon_prng.h
new file mode 100644 (file)
index 0000000..ff9ca03
--- /dev/null
+++ b/noekeon_prng.h
@@ -0,0 +1,40 @@
+/* noekeon_prng.h */
+/*
+ *   This file is part of the AVR-Crypto-Lib.
+ *   Copyright (C) 2006, 2007, 2008  Daniel Otte (daniel.otte@rub.de)
+ *
+ *   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/>.
+ */
+/**
+ * \author     Daniel Otte
+ * \date       2008-08-24
+ * \license GPLv3 or later
+ * \brief   random number generator based on noekeon running in CFB-mode
+ * 
+ */
+
+#ifndef PRNG_H_
+#define PRNG_H_
+
+#include <stdint.h>
+
+uint8_t random8(void);
+void random_block(void* dest);
+void srandom32(uint32_t seed);
+void random_seed(const void* buffer);
+void random_add(const void* buffer);
+
+#endif /* PRNG_H_*/
+
+