If I'm not restricted to an regex: 
my $ans = 1;
my $cnt = 0;
for (map {$cnt++ < 4 and
        $_=~/[0-9]+/ and $_ >= 0 and $_ <= 255 ? 1 : 0}
        split /\./, $ip)
{$ans &= $_};

[download]
Not super pretty, nor fast. But TIMTOWDI, as they say.

-Gryn

In reply to Less regex by gryng
in thread Matching an IP address by bort13

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