1 files changed, 134 insertions, 50 deletions

diff --git a/src/lib/libcrypto/bn/bn_nist.c b/src/lib/libcrypto/bn/bn_nist.c
index e14232fdbb..1fc94f55c3 100644
--- a/src/lib/libcrypto/bn/bn_nist.c
+++ b/src/lib/libcrypto/bn/bn_nist.c
@@ -59,6 +59,7 @@
 #include "bn_lcl.h"
 #include "cryptlib.h"
 
+
 #define BN_NIST_192_TOP (192+BN_BITS2-1)/BN_BITS2
 #define BN_NIST_224_TOP (224+BN_BITS2-1)/BN_BITS2
 #define BN_NIST_256_TOP (256+BN_BITS2-1)/BN_BITS2
@@ -101,60 +102,98 @@ static const BN_ULONG _nist_p_521[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
         0xFFFFFFFF,0x000001FF};
 #endif
 
+
+static const BIGNUM _bignum_nist_p_192 =
+        {
+        (BN_ULONG *)_nist_p_192,
+        BN_NIST_192_TOP,
+        BN_NIST_192_TOP,
+        0,
+        BN_FLG_STATIC_DATA
+        };
+
+static const BIGNUM _bignum_nist_p_224 =
+        {
+        (BN_ULONG *)_nist_p_224,
+        BN_NIST_224_TOP,
+        BN_NIST_224_TOP,
+        0,
+        BN_FLG_STATIC_DATA
+        };
+
+static const BIGNUM _bignum_nist_p_256 =
+        {
+        (BN_ULONG *)_nist_p_256,
+        BN_NIST_256_TOP,
+        BN_NIST_256_TOP,
+        0,
+        BN_FLG_STATIC_DATA
+        };
+
+static const BIGNUM _bignum_nist_p_384 =
+        {
+        (BN_ULONG *)_nist_p_384,
+        BN_NIST_384_TOP,
+        BN_NIST_384_TOP,
+        0,
+        BN_FLG_STATIC_DATA
+        };
+
+static const BIGNUM _bignum_nist_p_521 =
+        {
+        (BN_ULONG *)_nist_p_521,
+        BN_NIST_521_TOP,
+        BN_NIST_521_TOP,
+        0,
+        BN_FLG_STATIC_DATA
+        };
+
+
 const BIGNUM *BN_get0_nist_prime_192(void)
         {
-        static BIGNUM const_nist_192 = { (BN_ULONG *)_nist_p_192,
-                BN_NIST_192_TOP, BN_NIST_192_TOP, 0, BN_FLG_STATIC_DATA };
-        return &const_nist_192;
+        return &_bignum_nist_p_192;
         }
 
 const BIGNUM *BN_get0_nist_prime_224(void)
         {
-        static BIGNUM const_nist_224 = { (BN_ULONG *)_nist_p_224,
-                BN_NIST_224_TOP, BN_NIST_224_TOP, 0, BN_FLG_STATIC_DATA };
-        return &const_nist_224;
+        return &_bignum_nist_p_224;
         }
 
 const BIGNUM *BN_get0_nist_prime_256(void)
         {
-        static BIGNUM const_nist_256 = { (BN_ULONG *)_nist_p_256,
-                BN_NIST_256_TOP, BN_NIST_256_TOP, 0, BN_FLG_STATIC_DATA };
-        return &const_nist_256;
+        return &_bignum_nist_p_256;
         }
 
 const BIGNUM *BN_get0_nist_prime_384(void)
         {
-        static BIGNUM const_nist_384 = { (BN_ULONG *)_nist_p_384,
-                BN_NIST_384_TOP, BN_NIST_384_TOP, 0, BN_FLG_STATIC_DATA };
-        return &const_nist_384;
+        return &_bignum_nist_p_384;
         }
 
 const BIGNUM *BN_get0_nist_prime_521(void)
         {
-        static BIGNUM const_nist_521 = { (BN_ULONG *)_nist_p_521,
-                BN_NIST_521_TOP, BN_NIST_521_TOP, 0, BN_FLG_STATIC_DATA };
-        return &const_nist_521;
+        return &_bignum_nist_p_521;
         }
 
-#define BN_NIST_ADD_ONE(a)      while (!(*(a)=(*(a)+1)&BN_MASK2)) ++(a);
 
 static void nist_cp_bn_0(BN_ULONG *buf, BN_ULONG *a, int top, int max)
-        {
+        {
         int i;
-        BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
-        for (i = (top); i != 0; i--)
-                *_tmp1++ = *_tmp2++;
-        for (i = (max) - (top); i != 0; i--)
-                *_tmp1++ = (BN_ULONG) 0;
-        }
+        BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
+
+        OPENSSL_assert(top <= max);
+        for (i = (top); i != 0; i--)
+                *_tmp1++ = *_tmp2++;
+        for (i = (max) - (top); i != 0; i--)
+                *_tmp1++ = (BN_ULONG) 0;
+        }
 
 static void nist_cp_bn(BN_ULONG *buf, BN_ULONG *a, int top)
-        { 
+        { 
         int i;
-        BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
-        for (i = (top); i != 0; i--)
-                *_tmp1++ = *_tmp2++;
-        }
+        BN_ULONG *_tmp1 = (buf), *_tmp2 = (a);
+        for (i = (top); i != 0; i--)
+                *_tmp1++ = *_tmp2++;
+        }
 
 #if BN_BITS2 == 64
 #define bn_cp_64(to, n, from, m)        (to)[n] = (m>=0)?((from)[m]):0;
@@ -199,6 +238,11 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
                 *res;
         size_t   mask;
 
+        field = &_bignum_nist_p_192; /* just to make sure */
+
+        if (BN_is_negative(a) || a->top > 2*BN_NIST_192_TOP)
+                return BN_nnmod(r, field, a, ctx);
+
         i = BN_ucmp(field, a);
         if (i == 0)
                 {
@@ -208,9 +252,6 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         else if (i > 0)
                 return (r == a) ? 1 : (BN_copy(r ,a) != NULL);
 
-        if (top == BN_NIST_192_TOP)
-                return BN_usub(r, a, field);
-
         if (r != a)
                 {
                 if (!bn_wexpand(r, BN_NIST_192_TOP))
@@ -245,6 +286,11 @@ int BN_nist_mod_192(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         r->top = BN_NIST_192_TOP;
         bn_correct_top(r);
 
+        if (BN_ucmp(field, r) <= 0)
+                {
+                if (!BN_usub(r, r, field)) return 0;
+                }
+
         return 1;
         }
 
@@ -272,6 +318,11 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
                 *res;
         size_t   mask;
 
+        field = &_bignum_nist_p_224; /* just to make sure */
+
+        if (BN_is_negative(a) || a->top > 2*BN_NIST_224_TOP)
+                return BN_nnmod(r, field, a, ctx);
+
         i = BN_ucmp(field, a);
         if (i == 0)
                 {
@@ -281,9 +332,6 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         else if (i > 0)
                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 
-        if (top == BN_NIST_224_TOP)
-                return BN_usub(r, a, field);
-
         if (r != a)
                 {
                 if (!bn_wexpand(r, BN_NIST_224_TOP))
@@ -333,6 +381,11 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         r->top = BN_NIST_224_TOP;
         bn_correct_top(r);
 
+        if (BN_ucmp(field, r) <= 0)
+                {
+                if (!BN_usub(r, r, field)) return 0;
+                }
+
         return 1;
 #else   /* BN_BITS!=32 */
         return 0;
@@ -364,6 +417,11 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
                 *res;
         size_t   mask;
 
+        field = &_bignum_nist_p_256; /* just to make sure */
+
+        if (BN_is_negative(a) || a->top > 2*BN_NIST_256_TOP)
+                return BN_nnmod(r, field, a, ctx);
+
         i = BN_ucmp(field, a);
         if (i == 0)
                 {
@@ -373,9 +431,6 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         else if (i > 0)
                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 
-        if (top == BN_NIST_256_TOP)
-                return BN_usub(r, a, field);
-
         if (r != a)
                 {
                 if (!bn_wexpand(r, BN_NIST_256_TOP))
@@ -470,6 +525,11 @@ int BN_nist_mod_256(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         r->top = BN_NIST_256_TOP;
         bn_correct_top(r);
 
+        if (BN_ucmp(field, r) <= 0)
+                {
+                if (!BN_usub(r, r, field)) return 0;
+                }
+
         return 1;
 #else   /* BN_BITS!=32 */
         return 0;
@@ -505,6 +565,11 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
                 *res;
         size_t   mask;
 
+        field = &_bignum_nist_p_384; /* just to make sure */
+
+        if (BN_is_negative(a) || a->top > 2*BN_NIST_384_TOP)
+                return BN_nnmod(r, field, a, ctx);
+
         i = BN_ucmp(field, a);
         if (i == 0)
                 {
@@ -514,9 +579,6 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         else if (i > 0)
                 return (r == a)? 1 : (BN_copy(r ,a) != NULL);
 
-        if (top == BN_NIST_384_TOP)
-                return BN_usub(r, a, field);
-
         if (r != a)
                 {
                 if (!bn_wexpand(r, BN_NIST_384_TOP))
@@ -631,6 +693,11 @@ int BN_nist_mod_384(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
         r->top = BN_NIST_384_TOP;
         bn_correct_top(r);
 
+        if (BN_ucmp(field, r) <= 0)
+                {
+                if (!BN_usub(r, r, field)) return 0;
+                }
+
         return 1;
 #else   /* BN_BITS!=32 */
         return 0;
@@ -646,14 +713,35 @@ int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 #define BN_NIST_521_TOP_MASK    (BN_ULONG)0x1FF
 #endif
         int     top, ret = 0;
-        BN_ULONG *r_d;
         BIGNUM  *tmp;
 
+        field = &_bignum_nist_p_521; /* just to make sure */
+
+        if (BN_is_negative(a))
+                return BN_nnmod(r, field, a, ctx);
+
         /* check whether a reduction is necessary */
         top = a->top;
         if (top < BN_NIST_521_TOP  || ( top == BN_NIST_521_TOP &&
-           (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))))
-                return (r == a)? 1 : (BN_copy(r ,a) != NULL);
+            (!(a->d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))))
+                {
+                int i = BN_ucmp(field, a);
+                if (i == 0)
+                        {
+                        BN_zero(r);
+                        return 1;
+                        }
+                else
+                        {
+#ifdef BN_DEBUG
+                        OPENSSL_assert(i > 0); /* because 'field' is 1111...1111 */
+#endif
+                        return (r == a)? 1 : (BN_copy(r ,a) != NULL);
+                        }
+                }
+
+        if (BN_num_bits(a) > 2*521)
+                return BN_nnmod(r, field, a, ctx);
 
         BN_CTX_start(ctx);
         tmp = BN_CTX_get(ctx);
@@ -673,15 +761,11 @@ int BN_nist_mod_521(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
 
         if (!BN_uadd(r, tmp, r))
                 goto err;
-        top = r->top;
-        r_d = r->d;
-        if (top == BN_NIST_521_TOP  && 
-           (r_d[BN_NIST_521_TOP-1] & ~(BN_NIST_521_TOP_MASK)))
+
+        if (BN_ucmp(field, r) <= 0)
                 {
-                BN_NIST_ADD_ONE(r_d)
-                r->d[BN_NIST_521_TOP-1] &= BN_NIST_521_TOP_MASK; 
+                if (!BN_usub(r, r, field)) goto err;
                 }
-        bn_correct_top(r);
 
         ret = 1;
 err: