prng renamed to entropium

[avr-crypto-lib.git] / prng.c

diff --git a/prng.c b/prng.c
deleted file mode 100644 (file)
index ad73bdd..0000000
--- a/prng.c
+++ /dev/null
@@ -1,152 +0,0 @@
-/**
- * \file               prng.c
- * \author             Daniel Otte
- * \date               17.05.2006
- * \par License:
- *     GPL
- * \brief      This file contains an implementaition of a pseudo-random-number generator.
- * 
- * Extension 1:
- *     rndCore is expanded to 512 bits for more security.
- *
- * \verbatim
- *                      ################################################################################################
- *                      #                                                                                              #
- *                      #         +---------------------------+                                                        #
- *                      #         |                           |                             +---+                      #
- *                      #         V                           |                             |   |                      #
- *                      #      (concat)                       |                             |   V                      #
- *  +---------------+   #    o---------o             (xor)+---------+      o---------o      | o----o     o---------o   #    +--------------+
- *  | entropy Block | -----> | sha-256 | --(offset)-<     | rndCore | ---> | sha-256 | --+--+-| +1 |---> | sha-256 | -----> | random Block |
- *  +---------------+   #    o---------o             (xor)+---------+      o---------o   |    o----o     o---------o   #    +--------------+
- *                      #                                 (xor) (xor)                    |                             #
- *                      #                                   ^     ^                      |                             #
- *                      #                                    \   /                       |                             #
- *                      #                                   (offset)---------------------+                             #
- *                      #                                                                                              #
- *                      ################################################################################################
- * \endverbatim
- */
-
- /* \verbatim
- *                      ################################################################################################
- *                      #                                                                                              #
- *                      #         +---------------------------+                                                        #
- *                      #         |                           |                             +---+                      #
- *                      #         V                           |                             |   |                      #
- *                      #      (concat)                       |                             |   V                      #
- *  +---------------+   #    o---------o             (xor)+---------+      o---------o      | o----o     o---------o   #    +--------------+
- *  | entropy Block | -----> | sha-256 | --(offset)-<     | rndCore | ---> | sha-256 | --+--+-| +1 |---> | sha-256 | -----> | random Block |
- *  +---------------+   #    o---------o             (xor)+---------+      o---------o   |    o----o     o---------o   #    +--------------+
- *                      #                                 (xor) (xor)                    |                             #
- *                      #                                   ^     ^                      |                             #
- *                      #                                    \   /                       |                             #
- *                      #                                   (offset)---------------------+                             #
- *                      #                                                                                              #
- *                      ################################################################################################
- * \endverbatim
- */
-
-#include <stdint.h>
-#include <string.h>
-#include "sha256.h"
-#include "prng.h"
-
-/**
- * \brief secret entropy pool. 
- * This is the core of the random which is generated
- */
-uint32_t rndCore[16]; 
-
-/*************************************************************************/
-
-/**
- * \brief This function adds entropy to the central entropy pool
- * 
- * @param length This ist the length of the random data in BITS. 
- * @param data This is the random data which should be added to the entropy pool
-*/
-/* idea is: hash the message and add it via xor to rndCore
- *
- * length in bits 
- * 
- * we simply first "hash" rndCore, then entropy.
- */
-void addEntropy(unsigned length, void* data){
-       sha256_ctx_t s;
-       static uint8_t offset=0; /* selects if higher or lower half gets updated */
-       sha256_init(&s);
-       sha256_nextBlock(&s, rndCore);
-       while (length>=512){
-               sha256_nextBlock(&s, data);
-               data = (uint8_t*)data+ 512/8;
-               length -= 512;  
-       }
-       sha256_lastBlock(&s, data, length);
-       uint8_t i;
-       for (i=0; i<8; ++i){
-               rndCore[i+offset] ^= s.h[i];
-       }
-       offset ^= 8; /* hehe */
-}
-
-/*************************************************************************/
-/**
- * \brief This function fills a given buffer with 32 random bytes
- * @param b Pointer to buffer wich is to fill
- */
-void getRandomBlock(uint32_t *b){
-       sha256_ctx_t s;
-       uint8_t offset=8;
-       
-       sha256_init(&s);
-       sha256_lastBlock(&s, rndCore, 512); /* remeber the byte order! */
-       uint8_t i;
-       for (i=0; i<8; ++i){
-               rndCore[i+offset] ^= s.h[i];
-       }
-       offset ^= 8; /* hehe */
-       memcpy(b, s.h, 32); /* back up first hash in b */
-       ((uint8_t*)b)[*b&31]++;         /* the important increment step */
-       sha256_init(&s);
-       sha256_lastBlock(&s, b, 256);
-       memcpy(b, s.h, 32);
-}
-
-/*************************************************************************/
- 
-/**
- * \brief This function simply returns a random byte
- * @return a random byte
- */
-uint8_t getRandomByte(void){
-       static uint8_t block[32];
-       static uint8_t i=32;
-       
-       if (i==32){
-               getRandomBlock((void*)block);
-               i=0;
-       }       
-       return block[i++];
-}
-
-/*************************************************************************/
- 
-/**
- * \brief This function fills the given bock with length random bytes
- * @return a random byte
- */
- 
-void fillBlockRandom(void* block, unsigned length){
-       while(length>RANDOMBLOCK_SIZE){
-               getRandomBlock(block);
-               block = (uint8_t*)block + RANDOMBLOCK_SIZE;
-               length -= RANDOMBLOCK_SIZE;
-       }
-       while(length){
-               *((uint8_t*)block) = getRandomByte();
-               block= (uint8_t*)block +1; --length;
-       }
-}
- 
-