If you want to make sure that you are safe you should always use warnings, strict.pm, and taint mode(if you can). As an extra, you should try using the CPAN module Safe.

Now since I am so bored, I just want to clean up a bit of that code.

my @identity = qw(identity1 identity2 identity3 identity4);
foreach my $i (1..4) {
    my $identity = shift(@identity);
    #...
[download]

Wouldn't it be much better if you just iterated over the identity array because you don't use $i anywhere in there? ..:

my @identity = qw(identity1 identity2 identity3 identity4);
foreach my $identity (@identity) {
    #...
[download]

Tiptoeing up to a Perl hacker.
Dave AKA damian