Check IP addresses for good form

valid_dotted_quad takes a list of IP addresses and returns true if all are well-formed, false otherwise

sub valid_dotted_quad {
        my $all_valid = 1;
        my @sections;

ARGUMENT:for (@_) {
                next ARGUMENT unless $all_valid;
                next ARGUMENT unless ($all_valid &&= /^\d{1,3}\.\d{1,3
+}\.\d{1,3}
\.\d{1,3}$/o);
                @sections = split /\./, $_;
                for (@sections) {
                        next ARGUMENT unless ($all_valid &&= ($_ <= 0x
+FF));
                }
        }

        return $all_valid;
}
[download]

Comment on Check IP addresses for good form Download Code

Replies are listed 'Best First'.
RE: Check IP addresses for good form by knight (Friar) on Aug 16, 2000 at 20:16 UTC
Don't roll your own: `use Net::IPv4Addr qw( :all ); if ($ip = ipv4_checkip($str)) { # do something }` [download] This also handles IP+netmask strings like "123.45.67.89/255.255.255.0".	[reply] [d/l]
RE: Check IP addresses for good form by merlyn (Sage) on Aug 16, 2000 at 17:47 UTC
Unfortunately, this doesn't allow for all valid forms of an IP address, including such things as `127.1`. See the Socket manpage for the function `inet_aton` on which to base such a function. -- Randal L. Schwartz, Perl hacker	[reply]
(ar0n) Same thing, one line by ar0n (Priest) on Aug 16, 2000 at 18:26 UTC
`sub valid { (grep { (m/^(\d{1,3})$/ and $_ <= 255) or return 0 } split +(/[.]/, shift)) == 4 }` [download] update: changed (note the 'or return 0'). -- ar0n, Minimalist by nature	[reply] [d/l]
RE: (ar0n) Same thing, one line by merlyn (Sage) on Aug 16, 2000 at 18:44 UTC
Nope. That validates `128.215.bogus.65.1`. Try again! -- Randal L. Schwartz, Perl hacker	[reply]