ec/ecp_nistz256.c: improve ECDSA sign by 30-40%.

[openssl.git] / crypto / ec / ecdsa_ossl.c

diff --git a/crypto/ec/ecdsa_ossl.c b/crypto/ec/ecdsa_ossl.c
index 30458f1402addc2cc856e7f4a3310c4003aae0b7..a405d38b69eaea81aae080c234f7bedc1a46f70b 100644 (file)
--- a/crypto/ec/ecdsa_ossl.c
+++ b/crypto/ec/ecdsa_ossl.c
@@ -153,30 +153,33 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in,
     }
     while (BN_is_zero(r));
 
     }
     while (BN_is_zero(r));
 

-    /* compute the inverse of k */
-    if (EC_GROUP_get_mont_data(group) != NULL) {
-        /*
-         * We want inverse in constant time, therefore we utilize the fact
-         * order must be prime and use Fermat's Little Theorem instead.
-         */
-        if (!BN_set_word(X, 2)) {
-            ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
-            goto err;
-        }
-        if (!BN_mod_sub(X, order, X, order, ctx)) {
-            ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
-            goto err;
-        }
-        BN_set_flags(X, BN_FLG_CONSTTIME);
-        if (!BN_mod_exp_mont_consttime
-            (k, k, X, order, ctx, EC_GROUP_get_mont_data(group))) {
-            ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
-            goto err;
-        }
-    } else {
-        if (!BN_mod_inverse(k, k, order, ctx)) {
-            ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
-            goto err;
+    /* Check if optimized inverse is implemented */
+    if (EC_GROUP_do_inverse_ord(group, k, k, ctx) == 0) {
+        /* compute the inverse of k */
+        if (group->mont_data != NULL) {
+            /*
+             * We want inverse in constant time, therefore we utilize the fact
+             * order must be prime and use Fermats Little Theorem instead.
+             */
+            if (!BN_set_word(X, 2)) {
+                ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+                goto err;
+            }
+            if (!BN_mod_sub(X, order, X, order, ctx)) {
+                ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+                goto err;
+            }
+            BN_set_flags(X, BN_FLG_CONSTTIME);
+            if (!BN_mod_exp_mont_consttime(k, k, X, order, ctx,
+                                           group->mont_data)) {
+                ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+                goto err;
+            }
+        } else {
+            if (!BN_mod_inverse(k, k, order, ctx)) {
+                ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+                goto err;
+            }

         }
     }
 
         }
     }
 


@@ -407,9 +410,12 @@ int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
         goto err;
     }
     /* calculate tmp1 = inv(S) mod order */
         goto err;
     }
     /* calculate tmp1 = inv(S) mod order */

-    if (!BN_mod_inverse(u2, sig->s, order, ctx)) {
-        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
-        goto err;
+    /* Check if optimized inverse is implemented */
+    if (EC_GROUP_do_inverse_ord(group, u2, sig->s, ctx) == 0) {
+        if (!BN_mod_inverse(u2, sig->s, order, ctx)) {
+            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
+            goto err;
+        }

     }
     /* digest -> m */
     i = BN_num_bits(order);
     }
     /* digest -> m */
     i = BN_num_bits(order);