1 files changed, 67 insertions, 5 deletions

diff --git a/Cryptlib/OpenSSL/crypto/bn/bn_lib.c b/Cryptlib/OpenSSL/crypto/bn/bn_lib.c
index becb9571..80105fff 100644
--- a/Cryptlib/OpenSSL/crypto/bn/bn_lib.c
+++ b/Cryptlib/OpenSSL/crypto/bn/bn_lib.c
@@ -135,15 +135,16 @@ int BN_get_params(int which)
 
 const BIGNUM *BN_value_one(void)
 {
-    static BN_ULONG data_one = 1L;
-    static BIGNUM const_one = { &data_one, 1, 1, 0, BN_FLG_STATIC_DATA };
+    static const BN_ULONG data_one = 1L;
+    static const BIGNUM const_one =
+        { (BN_ULONG *)&data_one, 1, 1, 0, BN_FLG_STATIC_DATA };
 
     return (&const_one);
 }
 
 int BN_num_bits_word(BN_ULONG l)
 {
-    static const char bits[256] = {
+    static const unsigned char bits[256] = {
         0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
         5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
         6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
@@ -203,7 +204,7 @@ int BN_num_bits_word(BN_ULONG l)
         } else
 #endif
         {
-#if defined(SIXTEEN_BIT) || defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
+#if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
             if (l & 0xff00L)
                 return (bits[(int)(l >> 8)] + 8);
             else
@@ -773,7 +774,7 @@ int BN_is_bit_set(const BIGNUM *a, int n)
     j = n % BN_BITS2;
     if (a->top <= i)
         return 0;
-    return (((a->d[i]) >> j) & ((BN_ULONG)1));
+    return (int)(((a->d[i]) >> j) & ((BN_ULONG)1));
 }
 
 int BN_mask_bits(BIGNUM *a, int n)
@@ -852,3 +853,64 @@ int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl)
     }
     return bn_cmp_words(a, b, cl);
 }
+
+/*
+ * Constant-time conditional swap of a and b.
+ * a and b are swapped if condition is not 0.  The code assumes that at most one bit of condition is set.
+ * nwords is the number of words to swap.  The code assumes that at least nwords are allocated in both a and b,
+ * and that no more than nwords are used by either a or b.
+ * a and b cannot be the same number
+ */
+void BN_consttime_swap(BN_ULONG condition, BIGNUM *a, BIGNUM *b, int nwords)
+{
+    BN_ULONG t;
+    int i;
+
+    bn_wcheck_size(a, nwords);
+    bn_wcheck_size(b, nwords);
+
+    assert(a != b);
+    assert((condition & (condition - 1)) == 0);
+    assert(sizeof(BN_ULONG) >= sizeof(int));
+
+    condition = ((condition - 1) >> (BN_BITS2 - 1)) - 1;
+
+    t = (a->top ^ b->top) & condition;
+    a->top ^= t;
+    b->top ^= t;
+
+#define BN_CONSTTIME_SWAP(ind) \
+        do { \
+                t = (a->d[ind] ^ b->d[ind]) & condition; \
+                a->d[ind] ^= t; \
+                b->d[ind] ^= t; \
+        } while (0)
+
+    switch (nwords) {
+    default:
+        for (i = 10; i < nwords; i++)
+            BN_CONSTTIME_SWAP(i);
+        /* Fallthrough */
+    case 10:
+        BN_CONSTTIME_SWAP(9);   /* Fallthrough */
+    case 9:
+        BN_CONSTTIME_SWAP(8);   /* Fallthrough */
+    case 8:
+        BN_CONSTTIME_SWAP(7);   /* Fallthrough */
+    case 7:
+        BN_CONSTTIME_SWAP(6);   /* Fallthrough */
+    case 6:
+        BN_CONSTTIME_SWAP(5);   /* Fallthrough */
+    case 5:
+        BN_CONSTTIME_SWAP(4);   /* Fallthrough */
+    case 4:
+        BN_CONSTTIME_SWAP(3);   /* Fallthrough */
+    case 3:
+        BN_CONSTTIME_SWAP(2);   /* Fallthrough */
+    case 2:
+        BN_CONSTTIME_SWAP(1);   /* Fallthrough */
+    case 1:
+        BN_CONSTTIME_SWAP(0);
+    }
+#undef BN_CONSTTIME_SWAP
+}