X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Futil%2Fcrypto_random.c;h=25ba4db2a81ac94c9172c82c428590288ca7e474;hb=0ea8e006d5f5ef84e31e000607bd24a23f8fc1ed;hp=35dafd071b98afcda77b4b4d95c19927e645aeaf;hpb=79dea1de0667904be4ec99d7b65a61fa966da3f3;p=oweals%2Fgnunet.git

diff --git a/src/util/crypto_random.c b/src/util/crypto_random.c
index 35dafd071..25ba4db2a 100644
--- a/src/util/crypto_random.c
+++ b/src/util/crypto_random.c
@@ -55,6 +55,7 @@ GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode, uint32_t i)
   static unsigned int invokeCount;
 #endif
   uint32_t ret;
+  uint32_t ul;
 
   GNUNET_assert (i > 0);
 
@@ -65,8 +66,13 @@ GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode, uint32_t i)
       if ((invokeCount++ % 256) == 0)
         gcry_fast_random_poll ();
 #endif
-      gcry_randomize ((unsigned char *) &ret,
-                      sizeof (uint32_t), GCRY_STRONG_RANDOM);
+      ul = UINT32_MAX - (UINT32_MAX % i);
+      do
+	{
+	  gcry_randomize ((unsigned char *) &ret,
+			  sizeof (uint32_t), GCRY_STRONG_RANDOM);
+	}
+      while (ret >= ul);
       return ret % i;
     }
   else
@@ -99,9 +105,9 @@ GNUNET_CRYPTO_random_permute (enum GNUNET_CRYPTO_Quality mode, unsigned int n)
   ret = GNUNET_malloc (n * sizeof (unsigned int));
   for (i = 0; i < n; i++)
     ret[i] = i;
-  for (i = 0; i < n; i++)
+  for (i = n - 1; i > 0; i--)
     {
-      x = GNUNET_CRYPTO_random_u32 (mode, n);
+      x = GNUNET_CRYPTO_random_u32 (mode, i+1);
       tmp = ret[x];
       ret[x] = ret[i];
       ret[i] = tmp;
@@ -121,12 +127,18 @@ uint64_t
 GNUNET_CRYPTO_random_u64 (enum GNUNET_CRYPTO_Quality mode, uint64_t max)
 {
   uint64_t ret;
+  uint64_t ul;
 
   GNUNET_assert (max > 0);
   if (mode == GNUNET_CRYPTO_QUALITY_STRONG)
     {
-      gcry_randomize ((unsigned char *) &ret,
-                      sizeof (uint64_t), GCRY_STRONG_RANDOM);
+      ul = UINT64_MAX - (UINT64_MAX % max);
+      do
+	{
+	  gcry_randomize ((unsigned char *) &ret,
+			  sizeof (uint64_t), GCRY_STRONG_RANDOM);
+	}
+      while (ret >= ul);
       return ret % max;
     }
   else