/*#*
*#* $Log$
- *#* Revision 1.7 2007/02/09 15:49:54 asterix
- *#* Fix bug in randpool_stir and randpool_add. Typos.
+ *#* Revision 1.20 2007/06/07 16:06:39 batt
+ *#* Fix some doxygen errors.
+ *#*
+ *#* Revision 1.19 2007/02/15 13:54:26 asterix
+ *#* Rename randpool_getN in randpool_get. Fix bug in randpool_get.
+ *#*
+ *#* Revision 1.17 2007/02/15 13:40:42 asterix
+ *#* Fix bug in randpool_add and randpool_strir.
+ *#*
+ *#* Revision 1.16 2007/02/13 15:11:37 asterix
+ *#* Typo.
+ *#*
+ *#* Revision 1.14 2007/02/13 09:57:12 asterix
+ *#* Add directive #if in struct EntropyPool, and remove #else in randpool_add.
+ *#*
+ *#* Revision 1.13 2007/02/12 18:25:34 asterix
+ *#* Fix bug in randpool_getN.
+ *#*
+ *#* Revision 1.12 2007/02/12 09:47:39 asterix
+ *#* Remove randpool_save. Add randpool_pool.
+ *#*
+ *#* Revision 1.10 2007/02/12 09:03:32 asterix
+ *#* Add CONFIG_RANDPOOL_TIMER macro to swich on or off timer support
+ *#*
+ *#* Revision 1.9 2007/02/09 17:58:09 asterix
+ *#* Add macro CONFIG_RANDPOOL_TIMER.
*#*
*#* Revision 1.6 2007/02/09 09:24:38 asterix
*#* Typos. Add data_len in randpool_add and n_byte in randpool_push pototypes.
#include "randpool.h"
#include "md2.h"
-#include <string.h> //memset(), memcpy();
+#include <stdio.h> //sprintf();
+#include <string.h> //memset(), memcpy();
+
#include <cfg/compiler.h>
-#include <cfg/debug.h> //ASSERT()
-#include <drv/timer.h> //timer_clock();
+#include <cfg/debug.h> //ASSERT()
+#include <cfg/macros.h> //MIN(), ROUND_UP();
-#include <stdio.h> //sprintf();
+#if CONFIG_RANDPOOL_TIMER
+ #include <drv/timer.h> //timer_clock();
+#endif
for(int j = 0; j < n_byte; j++)
{
pool->pool_entropy[i] = pool->pool_entropy[i] ^ byte[j];
- i = (i++) % CONFIG_SIZE_ENTROPY_POOL;
+ i = (++i) % CONFIG_SIZE_ENTROPY_POOL;
}
pool->pos_add = i; // Update a insert bytes.
}
-/**
- * Add n_bit of entropy in entropy pool.
- */
-void randpool_add(EntropyPool *pool, void *data, size_t data_len, size_t entropy)
-{
- ticks_t event = timer_clock();
- uint32_t delta;
- uint8_t sep[] = "\xaa\xaa\xaa\xaa"; // ??
-
- randpool_push(pool, data, data_len); //Insert data to entropy pool.
-
- randpool_push(pool, sep, strlen(sep)); // ??
-
- /*Difference of time between a two accese to entropy pool.*/
- delta = event - pool->last_counter;
-
- randpool_push(pool, &delta, sizeof(delta));
-
- delta = delta & 0xff;
-
- randpool_push(pool, &delta, sizeof(delta));
-
- /*
- * Count of number entropy bit add with delta.
- */
- while(delta)
- {
- delta >>= 1;
- entropy++;
- }
-
- pool->entropy += entropy; //Update a entropy of the pool.
- pool->last_counter = event;
-}
-
-/* \
+/*
* This function stir entropy pool with MD2 function hash.
*
*/
{
size_t entropy = pool->entropy; //Save current calue of entropy.
Md2Context context;
- uint8_t tmp_buf[((sizeof(size_t) * 2) + sizeof(int)) * 2]; //Temporary buffer.
+ uint8_t tmp_buf[((sizeof(size_t) * 2) + sizeof(int)) * 2 + 1]; //Temporary buffer.
md2_init(&context); //Init MD2 algorithm.
- randpool_add(pool, "", 0, 0);
+ randpool_add(pool, NULL, 0);
- for (int i = 0; i < NUM_STIR_LOOP; i++)
+ for (int i = 0; i < (CONFIG_SIZE_ENTROPY_POOL / MD2_DIGEST_LEN); i++)
{
sprintf(tmp_buf, "%0x%0x%0x",pool->counter, i, pool->pos_add);
*/
md2_update(&context, pool->pool_entropy, CONFIG_SIZE_ENTROPY_POOL);
- md2_update(&context, tmp_buf, strlen(tmp_buf));
+ md2_update(&context, tmp_buf, sizeof(tmp_buf) - 1);
/*Insert a message digest in entropy pool.*/
- randpool_push(pool, md2_end(&context), CONFIG_MD2_BLOCK_LEN);
+ randpool_push(pool, md2_end(&context), MD2_DIGEST_LEN);
- pool->counter = (pool->counter + 1) & 0xFFFFFFFF; //Clamp a counter to 4 byte.
+ pool->counter = pool->counter + 1;
}
/*Insert in pool the difference between a two call of this function (see above).*/
- randpool_add(pool, "", 0, 0);
+ randpool_add(pool, NULL, 0);
pool->entropy = entropy; //Restore old value of entropy. We haven't add entropy.
}
+/**
+ * Add \param entropy bits from \param data buffer to the entropy \param pool
+ */
+void randpool_add(EntropyPool *pool, void *data, size_t entropy)
+{
+ uint8_t sep[] = "\xaa\xaa\xaa\xaa"; // ??
+ size_t data_len = ROUND_UP(entropy, 8) / 8; //Number of entropy byte in input.
+
+ randpool_push(pool, data, data_len); //Insert data to entropy pool.
+
+#if CONFIG_RANDPOOL_TIMER
-void randpool_init(EntropyPool *pool)
+ ticks_t event = timer_clock();
+ ticks_t delta;
+
+ /*Difference of time between a two accese to entropy pool.*/
+ delta = event - pool->last_counter;
+
+ randpool_push(pool, &event, sizeof(ticks_t));
+ randpool_push(pool, sep, sizeof(sep) - 1); // ??
+ randpool_push(pool, &delta, sizeof(delta));
+
+ /*
+ * Count of number entropy bit add with delta.
+ */
+ delta = delta & 0xff;
+ while(delta)
+ {
+ delta >>= 1;
+ entropy++;
+ }
+
+ pool->last_counter = event;
+
+#endif
+
+ pool->entropy += entropy; //Update a entropy of the pool.
+}
+
+/**
+ * Randpool function initialization.
+ * The entropy pool can be initialize also with
+ * a previous entropy pool.
+ */
+void randpool_init(EntropyPool *pool, void *_data, size_t len)
{
+ uint8_t *data;
+
+ data = (uint8_t *)_data;
memset(pool, 0, sizeof(EntropyPool));
- pool->pos_get = CONFIG_MD2_BLOCK_LEN;
+ pool->pos_get = MD2_DIGEST_LEN;
+
+#if CONFIG_RANDPOOL_TIMER
pool->last_counter = timer_clock();
+#endif
- //TODO: inizializzazione del timer di sistema.
+ if(data)
+ {
+ /*
+ * Initialize a entropy pool with a
+ * previous pool, and assume all pool as
+ * entropy.
+ */
+ len = MIN(len,(size_t)CONFIG_SIZE_ENTROPY_POOL);
+ memcpy(pool->pool_entropy, data, len);
+ pool->entropy = len;
+ }
}
return pool->entropy;
}
-void randpool_get(EntropyPool *pool, void *data, size_t n_byte)
+/**
+ * Get \param n_byte from entropy pool. If n_byte is larger than number
+ * byte of entropy in entropy pool, randpool_get continue
+ * to generate pseudocasual value from previous state of
+ * pool.
+ * \param n_byte number fo bytes to read.
+ * \param pool is the pool entropy context.
+ * \param _data is the pointer to write the random data to.
+ */
+void randpool_get(EntropyPool *pool, void *_data, size_t n_byte)
{
+ Md2Context context;
+ size_t i = pool->pos_get;
+ size_t n = n_byte;
+ size_t pos_write = 0; //Number of block has been written in data.
+ size_t len = MIN((size_t)MD2_DIGEST_LEN, n_byte);
+ uint8_t *data;
-}
+ data = (uint8_t *)_data;
-void randpool_getN(EntropyPool *pool, void *data, size_t n_byte)
-{
-}
+ /* Test if i + CONFIG_MD2_BLOCK_LEN is inside of entropy pool.*/
+ ASSERT((MD2_DIGEST_LEN + i) < CONFIG_SIZE_ENTROPY_POOL);
+
+ md2_init(&context);
+
+ while(n > 0)
+ {
+
+ /*Hash previous state of pool*/
+ md2_update(&context, &pool->pool_entropy[i], MD2_DIGEST_LEN);
+
+ memcpy(&data[pos_write], md2_end(&context), len);
+
+ pos_write += len; //Update number of block has been written in data.
+ n -= len; //Number of byte copied in data.
+
+ len = MIN(n,(size_t)MD2_DIGEST_LEN);
+
+ i = (i + MD2_DIGEST_LEN) % CONFIG_SIZE_ENTROPY_POOL;
+
+ /* If we haven't more entropy pool to hash, we stir it.*/
+ if(i < MD2_DIGEST_LEN)
+ {
+ randpool_stir(pool);
+ i = pool->pos_get;
+ }
+
+ }
+
+ pool->pos_get = i; //Current number of byte we get from pool.
+ pool->entropy -= n_byte; //Update a entropy.
+
+ /*If we get all entropy entropy is 0*/
+ if(pool->entropy < 0)
+ pool->entropy = 0;
-bool randpool_save(void *data)
-{
}
-uint8_t *randpool_load(void)
+/**
+ * Return a pointer to entropy pool.
+ */
+uint8_t *randpool_pool(EntropyPool *pool)
{
+ return pool->pool_entropy;
}
projects / bertos.git / blobdiff