I've been playing around with Safe, but I've hit a problem with @ISA / inheritance, and I can't seem to work round it. I managed to strip everything right back to a very small example which shows the problem.
#! /usr/bin/perl -w
use strict;
use Safe;
my $CODE = << 'END';
package A;
sub new {
my($class) = @_;
bless { }, $class;
}
package B;
our @ISA = qw(A);
END
# If I uncomment this line, everything works.
# eval $CODE;
my $safe = Safe->new();
$safe->reval($CODE);
warn "code - $@" if $@;
$safe->reval("B->new();");
warn "new - $@" if $@;
When I run this, I get "Can't locate package A for @B::ISA" (twice). If I uncomment the eval, then the problem goes away - but of course in the real app, I don't want to eval the untrusted code outside of Safe (so just suggesting that I uncomment it, isn't going to help me much :-)
Can someone explain to me what's going on? Any idea how I might get round this problem?
Have fun,
rdw
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