Crypto Program - A perl "script" to protect data

#!/usr/bin/perl
#************Random Signature V1,0******************#
#* CodeName: Crypto v1.7 alpha                     *#
#* Coder: K22 - www.klakice.astahost.com;         *#
#* Date: 07/11/2004;                                *#
#* License: GNU/GPL;                               *#
#***************************************************#

sub keygen {                    #Generate a code from a char, not just a simple ASCII
#my (@togen,@plus)=@_;
my @plus=@plus;
my @togen=@_;
my $i=0;
#print $plus[0]."-0-".$plus[1]."-1-".$plus[2]."-2-".$plus[3]."-3-\n";
foreach $chr(@togen) {
$ascii=ord($chr);
$togen[$i]=$ascii+$#togen+ord($#togen)+$plus[0]-$plus[1]-(($plus[2]-$plus[3])*2)+$#plus-ord($#plus);
$i++;
}
  return (@togen);
}

sub degen {                     #Degenerate the coede made by the keygen function
#my (@tode,@plus)=@_;
my @plus=@plus;
my @tode=@_;
my $i=0;
#print $plus[0]."-0-".$plus[1]."-1-".$plus[2]."-2-".$plus[3]."-3-\n";
foreach $chrz(@tode) {
$ascii=$chrz-$#tode-ord($#tode)-$plus[0]+$plus[1]+(($plus[2]-$plus[3])*2)-$#plus+ord($#plus);
$tode[$i]=chr($ascii);
$i++;
}
return (@tode);
}

sub alphagen {                 #Alpha generator, it's a new function, I'll use ti for modify the lenght of the output
$let="a";
for($i=1;$i<=26;$i++){
push(@alpha,$let);
$let++;
}
return (@alpha);
}

sub relpos {                 #Calculations of valide array positions
my ($y,$limit,@refarr)=@_;
my $p=0;
my @val;
for($p=0;$p<=$limit;$p++){
$y=$_[0]+$p;
while(!exists($refarr[$y])){
$val[4].= $#refarr."s-$p\n";
$y=$y-$#refarr-1;
$val[4].= $y."p-$p\n";
}
$val[$p]=$y;
}
return(@val);
}

sub divi(@){                    #Generator of passwd number
my @whr=@_;
my $temp;
$temp=$secpass[$whr[0]]*$secpass[$whr[1]];
$temp=$temp*($secpass[$whr[0]]+$secpass[$whr[1]]-$secpass[$whr[2]]);
return($temp);
}

sub ende {                         #Core of the algorithms
my ($cho,@toende)=@_;
my $x=0;
my $temp;
my @crypto;
my $eli;
foreach $eli(@toende) {
@pos=relpos($x,2,@secpass);
$temp=divi(@pos);
if($cho==1) {
$cc=$eli-$temp;
}
elsif($cho==0) {
$cc=$eli+$temp;
}
$crypto[$x]=$cc;
$x++;
}
return(@crypto);
}

sub timerize {                  #Function to determinate how long the message can be read
print "Select the time of the message default:1 m(Until the end of the month)\n";
print "M=End of the month\n";
print "D=End of the day\n";
print "H=End of the hour\n";
$lim=<>;
chomp($lim);
my ($sec,$min,$h,$mday,$mon,$year,$wday,$yday,$isdst)=localtime();
$mon+=1;
$year+=1900;
my @crdate=($year,$mon);
if($lim =~ m/d/i){
push(@crdate,$mday);
print "Limit set to a day\n";
}
elsif($lim =~ m/h/i){
push(@crdate,$mday,$h);
print "Limit set to a hour\n";
}
else{
print "Limit set to a month";
}
return(@crdate)
}


#Main, if you love calling it so...
while(!($pass) || !($text)){
print "Insert Pass:\n";
$pass=<>;
print "Insert Text:\n";
$text=<>;
print "To decrypt DECA\n";
print "To hashing the string HASH(NOT YET)\n";
print "To decrypt o crypt a text with a time limit [DECA] TIME\n";
$opt=<>;
chomp ($pass,$text,$opt);
}
@chrpass= split(//,$pass);

if($opt =~ m/deca/i) {
$cho=1;
if($opt=~ m/time/i) {
@plus=timerize();
}
print $plus[0]."-0-".$plus[1]."-1-".$plus[2]."-2-".$plus[3]."-3-\n";
#@secpass=keygen(@chrpass,@plus);
@secpass=keygen(@chrpass);
@decry=split(/\|/,$text);
@crypto=ende(1,@decry);
#@crypto=degen(@crypto,@plus);
@crypto=degen(@crypto);
}
else {
if($opt =~ m/hash/i) {
#@plus=hashing(@chrpass);
$cho=2;
}
elsif($opt =~ m/time/i) {
@plus=timerize();
$cho=3;
}
else{
@plus=();
$cho=0;
}
#print $plus[0]."-0-".$plus[1]."-1-".$plus[2]."-2-".$plus[3]."-3-\n";
#@secpass=keygen(@chrpass,@plus);
@secpass=keygen(@chrpass);
@chrtext= split(//,$text);
#@sectext=keygen(@chrtext,@plus);
@sectext=keygen(@chrtext);
@crypto=ende(0,@sectext);
}

foreach (@crypto){
                 $tofile .= $crypto[$x]."|";
                 print $crypto[$x]."|";
                 $x++;
}
if(@crypto){
print "\n\nLeaving...The message has been write in out.txt\n\n 'njoy\n\n";
open(OUT, ">out.txt");
print OUT $tofile;
close(OUT);
}