Hello, recently I recieved a lot of mocking for my 'unsafe' mailform combined with some poor CGI script. Now I am doing some experiments and excercises figuring out what is secure content, and the so-called 'injections'. I`ve put a very basic module free code performing very simple tasks so I need some revisions, and if it`s the right way. 

#!/usr/bin/perl -wT
use strict;
use utf8;
sub pass_env {
    my (@pass1) = split("&", $_[0]);
    my ($pass2) = join("=", @pass1);
    my (%pass3) = split("=", $pass2);
    return %pass3;
}
sub check_mail {
        #use Email::Valid instead
    if ( (my @valid = split("@", $_[0]) )== 2 ) {
        #continue with regex later...
                return 1;
    }
    else {
        return 0;
    }
}
sub check_vars {
        #use htmlspecialchars() based check
    foreach (@_) {
        if  ( /[><;():]+/ ) {
            return 0;
        }
    }
    return 1;
}
##
my $str = "sub=hello&mail=sometext&text=beeee mooo "; # $ENV{'QUERY_ST
+RING} simulation
my %hash = &pass_env($str);


if ( &check_vars($hash{'sub'}, $hash{'mail'}, $hash{'text'})) { 
    if ( &check_mail($hash{'mail'}) ) {
    print $hash{'sub'},"\n";
    print $hash{'mail'}, "\n";
    print $hash{'text'}, "\n";
    }
    else {
        print "Invalid email.\n";
    }
}
else {
    print "Please, fill all forms.\n";
}

[download]

so I need some opinions good or bad, no matter.

In reply to Is that a decent concept? by heatblazer

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