Import of old SSLeay release: SSLeay 0.9.0b

[openssl.git] / perl / mul.pl

diff --git a/perl/mul.pl b/perl/mul.pl
new file mode 100644 (file)
index 0000000..611a760
--- /dev/null
+++ b/perl/mul.pl
@@ -0,0 +1,56 @@
+#!/usr/bin/perl
+
+use ExtUtils::testlib;
+
+use SSLeay;
+
+
+sub mul
+       {
+       my($ab,$cd,$num)=@_;
+
+       if ($num <= 4096)
+               {
+               return($ab*$cd);
+               }
+       else
+               {
+               my($a,$b,$c,$d,$n,$ac,$bd,$m,$t1,$t2);
+
+               $n=$num/2;
+
+               $a=$ab->mask_bits($n);
+               $b=$ab->rshift($n);
+               $c=$cd->mask_bits($n);
+               $d=$cd->rshift($n);
+
+               $t1=($b-$a);
+               $t2=($c-$d);
+               $m= &mul($t1,$t2,$n);
+               $ac=&mul($a,$c,$n);
+               $bd=&mul($b,$d,$n);
+               $m=$m+$ac+$bd;
+               $m=$m->lshift($n);
+               $bd=$bd->lshift($num);
+
+               $r=$ac+$m+$bd;
+               return($r);
+               }
+       }
+
+$num=4096*32;
+$a=SSLeay::BN::rand($num);
+$b=SSLeay::BN::rand($num);
+
+#for (1 .. 10)
+       {
+       $r=&mul($a,$b,$num);
+       }
+
+#for (1 .. 10)
+       {
+       $rr=$a*$b;
+       }
+
+$res=$rr-$r;
+print $res->bn2hex()."\n";