I went to report the doc error, and found a major, easy-to-fix bug that's been ignored for two years. ipv4_chkip will pass any string of four or more integers between 0 and 255 connected by .'s. The deal-breaker here is the 'four or more' instead of 'exactly four.'

So I can't recommend it. Perhaps try Regexp::Common instead.

use Net::IPv4Addr qw(:all);
use Regexp::Common qw(net);

my @var = qw(23.23.109.103 12324.123.12.1 1.2.3.4.5.6);

print "Net::IFv4Addr:\n";
ipv4_chkip($_) and print "$_ is good\n" for @var;
print "Regexp::Common:\n";
/^$RE{net}{IPv4}$/ and print "$_ is good\n" for @var;
[download]

produces

Net::IFv4Addr:
23.23.109.103 is good
1.2.3.4.5.6 is good
Regexp::Common:
23.23.109.103 is good
[download]

Note that you do need to anchor the start and end of the regexp with ^ and $, 'cause just /$RE{net}{IPv4}/ would match 312.45.32.4.