Add OPENSSL_NO_ECDH guards

[oweals/openssl.git] / crypto / ec / ec_cvt.c

diff --git a/crypto/ec/ec_cvt.c b/crypto/ec/ec_cvt.c
index 20782569a9faddf1332869e3e624b60ab379c3c4..682425de38d2187208536e0944723a03a5041a64 100644 (file)
--- a/crypto/ec/ec_cvt.c
+++ b/crypto/ec/ec_cvt.c
@@ -64,24 +64,13 @@
  * The Contribution is licensed pursuant to the OpenSSL open source
  * license provided above.
  *
- * In addition, Sun covenants to all licensees who provide a reciprocal
- * covenant with respect to their own patents if any, not to sue under
- * current and future patent claims necessarily infringed by the making,
- * using, practicing, selling, offering for sale and/or otherwise
- * disposing of the Contribution as delivered hereunder 
- * (or portions thereof), provided that such covenant shall not apply:
- *  1) for code that a licensee deletes from the Contribution;
- *  2) separates from the Contribution; or
- *  3) for infringements caused by:
- *       i) the modification of the Contribution or
- *      ii) the combination of the Contribution with other software or
- *          devices where such combination causes the infringement.
- *
  * The elliptic curve binary polynomial software is originally written by
  * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories.
  *
  */
 
+
+
 #include <openssl/err.h>
 #include "ec_lcl.h"
 
@@ -91,7 +80,35 @@ EC_GROUP *EC_GROUP_new_curve_GFp(const BIGNUM *p, const BIGNUM *a, const BIGNUM
        const EC_METHOD *meth;
        EC_GROUP *ret;
 
-       meth = EC_GFp_nist_method();
+#if defined(OPENSSL_BN_ASM_MONT)
+       /*
+        * This might appear controversial, but the fact is that generic
+        * prime method was observed to deliver better performance even
+        * for NIST primes on a range of platforms, e.g.: 60%-15%
+        * improvement on IA-64, ~25% on ARM, 30%-90% on P4, 20%-25%
+        * in 32-bit build and 35%--12% in 64-bit build on Core2...
+        * Coefficients are relative to optimized bn_nist.c for most
+        * intensive ECDSA verify and ECDH operations for 192- and 521-
+        * bit keys respectively. Choice of these boundary values is
+        * arguable, because the dependency of improvement coefficient
+        * from key length is not a "monotone" curve. For example while
+        * 571-bit result is 23% on ARM, 384-bit one is -1%. But it's
+        * generally faster, sometimes "respectfully" faster, sometimes
+        * "tolerably" slower... What effectively happens is that loop
+        * with bn_mul_add_words is put against bn_mul_mont, and the
+        * latter "wins" on short vectors. Correct solution should be
+        * implementing dedicated NxN multiplication subroutines for
+        * small N. But till it materializes, let's stick to generic
+        * prime method...
+        *                                              <appro>
+        */
+       meth = EC_GFp_mont_method();
+#else
+       if (BN_nist_mod_func(p))
+               meth = EC_GFp_nist_method();
+       else
+               meth = EC_GFp_mont_method();
+#endif
        
        ret = EC_GROUP_new(meth);
        if (ret == NULL)
@@ -99,26 +116,14 @@ EC_GROUP *EC_GROUP_new_curve_GFp(const BIGNUM *p, const BIGNUM *a, const BIGNUM
 
        if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx))
                {
-               /* remove the last error code form the error queue */
-               ERR_get_error();
-               /* try the normal mont method */
                EC_GROUP_clear_free(ret);
-               meth = EC_GFp_mont_method();
-
-               ret = EC_GROUP_new(meth);
-               if (ret == NULL)
-                       return NULL;
-
-               if (!EC_GROUP_set_curve_GFp(ret, p, a, b, ctx))
-                       {
-                       EC_GROUP_clear_free(ret);
-                       return NULL;
-                       }
+               return NULL;
                }
 
        return ret;
        }
 
+#ifndef OPENSSL_NO_EC2M
 EC_GROUP *EC_GROUP_new_curve_GF2m(const BIGNUM *p, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
        {
        const EC_METHOD *meth;
@@ -138,3 +143,4 @@ EC_GROUP *EC_GROUP_new_curve_GF2m(const BIGNUM *p, const BIGNUM *a, const BIGNUM
 
        return ret;
        }
+#endif