Add 64-bit support to BN_nist_mod_244 and engage BN_nist_mod_* on 64-bit
authorAndy Polyakov <appro@openssl.org>
Thu, 24 Apr 2008 10:04:26 +0000 (10:04 +0000)
committerAndy Polyakov <appro@openssl.org>
Thu, 24 Apr 2008 10:04:26 +0000 (10:04 +0000)
platforms.

crypto/bn/bn_nist.c
crypto/ec/ecp_nist.c

index d8b443c..9419f3b 100644 (file)
@@ -76,7 +76,7 @@ static const BN_ULONG _nist_p_224[][BN_NIST_224_TOP] = {
        {0x0000000000000001ULL,0xFFFFFFFF00000000ULL,
         0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL},
        {0x0000000000000002ULL,0xFFFFFFFE00000000ULL,
-        0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL}
+        0xFFFFFFFFFFFFFFFFULL,0x00000001FFFFFFFFULL} /* this one is "carry-full" */
        };
 static const BN_ULONG _nist_p_256[][BN_NIST_256_TOP] = {
        {0xFFFFFFFFFFFFFFFFULL,0x00000000FFFFFFFFULL,
@@ -148,6 +148,8 @@ static const BN_ULONG _nist_p_521[] = {0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
        0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
        0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,0xFFFFFFFF,
        0xFFFFFFFF,0x000001FF};
+#else
+#error "unsupported BN_BITS2"
 #endif
 
 const BIGNUM *BN_get0_nist_prime_192(void)
@@ -321,7 +323,6 @@ typedef BN_ULONG (*bn_addsub_f)(BN_ULONG *,const BN_ULONG *,const BN_ULONG *,int
 int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
        BN_CTX *ctx)
        {
-#if BN_BITS2 == 32
        int     top = a->top, i;
        int     carry;
        BN_ULONG *r_d, *a_d = a->d;
@@ -354,8 +355,16 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
        else
                r_d = a_d;
 
+#if BN_BITS2==64
+       /* copy upper 256 bits of 448 bit number ... */
+       nist_cp_bn_0(t_d, a_d + (BN_NIST_224_TOP-1), top - (BN_NIST_224_TOP-1), BN_NIST_224_TOP);
+       /* ... and right shift by 32 to obtain upper 224 bits */
+       nist_set_224(buf, t_d, 14, 13, 12, 11, 10, 9, 8);
+       /* truncate lower part to 224 bits too */
+       r_d[BN_NIST_224_TOP-1] &= BN_MASK2l;
+#else
        nist_cp_bn_0(buf, a_d + BN_NIST_224_TOP, top - BN_NIST_224_TOP, BN_NIST_224_TOP);
-
+#endif
        nist_set_224(t_d, buf, 10, 9, 8, 7, 0, 0, 0);
        carry = bn_add_words(r_d, r_d, t_d, BN_NIST_224_TOP);
        nist_set_224(t_d, buf, 0, 13, 12, 11, 0, 0, 0);
@@ -365,9 +374,17 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
        nist_set_224(t_d, buf, 0, 0, 0, 0, 13, 12, 11);
        carry -= bn_sub_words(r_d, r_d, t_d, BN_NIST_224_TOP);
 
+#if BN_BITS2==64
+       carry = (int)(r_d[BN_NIST_224_TOP-1]>>32);
+#endif
        u.f = bn_sub_words;
        if (carry > 0)
+               {
                carry = bn_sub_words(r_d,r_d,_nist_p_224[carry-1],BN_NIST_224_TOP);
+#if BN_BITS2==64
+               carry=(int)(~(r_d[BN_NIST_224_TOP-1]>>32))&1;
+#endif
+               }
        else if (carry < 0)
                {
                /* it's a bit more comlicated logic in this case.
@@ -392,9 +409,6 @@ int BN_nist_mod_224(BIGNUM *r, const BIGNUM *a, const BIGNUM *field,
        bn_correct_top(r);
 
        return 1;
-#else  /* BN_BITS!=32 */
-       return 0;
-#endif
        }
 
 #define nist_set_256(to, from, a1, a2, a3, a4, a5, a6, a7, a8) \
index 71893d5..2a5682e 100644 (file)
@@ -112,10 +112,6 @@ const EC_METHOD *EC_GFp_nist_method(void)
        return &ret;
        }
 
-#if BN_BITS2 == 64
-#define        NO_32_BIT_TYPE
-#endif
-
 int ec_GFp_nist_group_copy(EC_GROUP *dest, const EC_GROUP *src)
        {
        dest->field_mod_func = src->field_mod_func;
@@ -139,34 +135,12 @@ int ec_GFp_nist_group_set_curve(EC_GROUP *group, const BIGNUM *p,
        if (BN_ucmp(BN_get0_nist_prime_192(), p) == 0)
                group->field_mod_func = BN_nist_mod_192;
        else if (BN_ucmp(BN_get0_nist_prime_224(), p) == 0)
-               {
-#ifndef NO_32_BIT_TYPE
                group->field_mod_func = BN_nist_mod_224;
-#else
-               ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
-               goto err;
-#endif
-               }
        else if (BN_ucmp(BN_get0_nist_prime_256(), p) == 0)
-               {
-#ifndef NO_32_BIT_TYPE
                group->field_mod_func = BN_nist_mod_256;
-#else
-               ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
-               goto err;
-#endif
-               }
        else if (BN_ucmp(BN_get0_nist_prime_384(), p) == 0)
-               {
-#ifndef NO_32_BIT_TYPE
                group->field_mod_func = BN_nist_mod_384;
-#else
-               ECerr(EC_F_EC_GFP_NIST_GROUP_SET_CURVE, EC_R_NOT_A_SUPPORTED_NIST_PRIME);
-               goto err;
-#endif
-               }
        else if (BN_ucmp(BN_get0_nist_prime_521(), p) == 0)
-               /* this one works in the NO_32_BIT_TYPE case */
                group->field_mod_func = BN_nist_mod_521;
        else
                {