Allow for higher granularity of entropy estimates by using 'double'

[openssl.git] / crypto / rand / md_rand.c

diff --git a/crypto/rand/md_rand.c b/crypto/rand/md_rand.c
index df3a9e6068b68ac05f426999e250b0d79f23de0f..34843d04dbe32c39432edd2c4f8a79af5df57e5e 100644 (file)
--- a/crypto/rand/md_rand.c
+++ b/crypto/rand/md_rand.c
@@ -56,7 +56,7 @@
  * [including the GNU Public Licence.]
  */
 
-#define ENTROPY_NEEDED 32  /* require 128 bits of randomness */
+#define ENTROPY_NEEDED 16  /* require 128 bits = 16 bytes of randomness */
 
 #ifndef MD_RAND_DEBUG
 # ifndef NDEBUG
@@ -138,13 +138,13 @@ static int state_num=0,state_index=0;
 static unsigned char state[STATE_SIZE+MD_DIGEST_LENGTH];
 static unsigned char md[MD_DIGEST_LENGTH];
 static long md_count[2]={0,0};
-static unsigned entropy=0;
+static double entropy=0;
 
 const char *RAND_version="RAND" OPENSSL_VERSION_PTEXT;
 
 static void ssleay_rand_cleanup(void);
 static void ssleay_rand_seed(const void *buf, int num);
-static void ssleay_rand_add(const void *buf, int num, int add_entropy);
+static void ssleay_rand_add(const void *buf, int num, double add_entropy);
 static int ssleay_rand_bytes(unsigned char *buf, int num);
 static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num);
 
@@ -172,7 +172,7 @@ static void ssleay_rand_cleanup(void)
        entropy=0;
        }
 
-static void ssleay_rand_add(const void *buf, int num, int add)
+static void ssleay_rand_add(const void *buf, int num, double add)
        {
        int i,j,k,st_idx;
        long md_c[2];
@@ -286,7 +286,7 @@ static void ssleay_rand_add(const void *buf, int num, int add)
 #ifndef THREADS        
        assert(md_c[1] == md_count[1]);
 #endif
-       if (entropy < ENTROPY_NEEDED)
+       if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */
            entropy += add;
        }