use XML::Twig;

use strict;
use warnings;

my $data = do {local $/; <DATA>};

my $twig = new XML::Twig(twig_handlers => {
	'//target[@type="aim"]/*' => sub {
		print $_->tag, ' ', $_->text, "\n";
	},
});
$twig->parse($data);

__DATA__
<result>
  <target type="aim">
    <tag1>123</tag1>
    <tag2>456</tag2>
    <tag3>234</tag3>
  </target>
</result>