1 files changed, 94 insertions, 13 deletions

diff --git a/src/lib/libcrypto/bn/bn_rand.c b/src/lib/libcrypto/bn/bn_rand.c
index 21ecbc04ed..acd0619921 100644
--- a/src/lib/libcrypto/bn/bn_rand.c
+++ b/src/lib/libcrypto/bn/bn_rand.c
@@ -76,7 +76,7 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
 
         bytes=(bits+7)/8;
         bit=(bits-1)%8;
-        mask=0xff<<bit;
+        mask=0xff<<(bit+1);
 
         buf=(unsigned char *)OPENSSL_malloc(bytes);
         if (buf == NULL)
@@ -100,25 +100,48 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
                         goto err;
                 }
 
-        if (top)
+#if 1
+        if (pseudorand == 2)
                 {
-                if (bit == 0)
+                /* generate patterns that are more likely to trigger BN
+                   library bugs */
+                int i;
+                unsigned char c;
+
+                for (i = 0; i < bytes; i++)
+                        {
+                        RAND_pseudo_bytes(&c, 1);
+                        if (c >= 128 && i > 0)
+                                buf[i] = buf[i-1];
+                        else if (c < 42)
+                                buf[i] = 0;
+                        else if (c < 84)
+                                buf[i] = 255;
+                        }
+                }
+#endif
+
+        if (top != -1)
+                {
+                if (top)
                         {
-                        buf[0]=1;
-                        buf[1]|=0x80;
+                        if (bit == 0)
+                                {
+                                buf[0]=1;
+                                buf[1]|=0x80;
+                                }
+                        else
+                                {
+                                buf[0]|=(3<<(bit-1));
+                                }
                         }
                 else
                         {
-                        buf[0]|=(3<<(bit-1));
-                        buf[0]&= ~(mask<<1);
+                        buf[0]|=(1<<bit);
                         }
                 }
-        else
-                {
-                buf[0]|=(1<<bit);
-                buf[0]&= ~(mask<<1);
-                }
-        if (bottom) /* set bottom bits to whatever odd is */
+        buf[0] &= ~mask;
+        if (bottom) /* set bottom bit if requested */
                 buf[bytes-1]|=1;
         if (!BN_bin2bn(buf,bytes,rnd)) goto err;
         ret=1;
@@ -140,3 +163,61 @@ int     BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom)
         {
         return bnrand(1, rnd, bits, top, bottom);
         }
+
+#if 1
+int     BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom)
+        {
+        return bnrand(2, rnd, bits, top, bottom);
+        }
+#endif
+
+/* random number r:  0 <= r < range */
+int     BN_rand_range(BIGNUM *r, BIGNUM *range)
+        {
+        int n;
+
+        if (range->neg || BN_is_zero(range))
+                {
+                BNerr(BN_F_BN_RAND_RANGE, BN_R_INVALID_RANGE);
+                return 0;
+                }
+
+        n = BN_num_bits(range); /* n > 0 */
+
+        if (n == 1)
+                {
+                if (!BN_zero(r)) return 0;
+                }
+        else if (BN_is_bit_set(range, n - 2))
+                {
+                do
+                        {
+                        /* range = 11..._2, so each iteration succeeds with probability >= .75 */
+                        if (!BN_rand(r, n, -1, 0)) return 0;
+                        }
+                while (BN_cmp(r, range) >= 0);
+                }
+        else
+                {
+                /* range = 10..._2,
+                 * so  3*range (= 11..._2)  is exactly one bit longer than  range */
+                do
+                        {
+                        if (!BN_rand(r, n + 1, -1, 0)) return 0;
+                        /* If  r < 3*range,  use  r := r MOD range
+                         * (which is either  r, r - range,  or  r - 2*range).
+                         * Otherwise, iterate once more.
+                         * Since  3*range = 11..._2, each iteration succeeds with
+                         * probability >= .75. */
+                        if (BN_cmp(r ,range) >= 0)
+                                {
+                                if (!BN_sub(r, r, range)) return 0;
+                                if (BN_cmp(r, range) >= 0)
+                                        if (!BN_sub(r, r, range)) return 0;
+                                }
+                        }
+                while (BN_cmp(r, range) >= 0);
+                }
+
+        return 1;
+        }