Match a Range of IP's

Dru has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Match a Range of IP's by conrad (Beadle) on Sep 30, 2004 at 16:15 UTC
`[1-99]` is a character range, not a number range, so it'll match 1 .. 9 or 9 (i.e. it's the same as `[1-9]`). One solution is to use `[1-9]\d?` instead, which will match 1 .. 9 and any two-digit number (but if you ever get IP addresses of the form "001" this will fail). A better option would be to use `(\d+)` and add " `&& $1 >= 1 && $1 <= 99`" to the end of the line; bear in mind that that will run into trouble if you have multiple IP addresses per line because of your `/g` though...	[reply] [d/l] [select]
Re: Match a Range of IP's by bpphillips (Friar) on Sep 30, 2004 at 16:13 UTC
your `[1-99]` really means match only one character `[1-9]` (you can't do ranges on two-digit numbers). You need this: `while (<DATA>){ print "$_\n" if m/^192\.168\.[1-9][0-9]?\.\d+$/; }` [download]	[reply] [d/l] [select]
Re: Match a Range of IP's by Zaxo (Archbishop) on Sep 30, 2004 at 16:21 UTC
The `[1-99]` doesn't do what you think. It is a character class which will match a single digit in the range one to nine. That corresponds to what you see. You can match and test with `while (<DATA>) { print if /^192\.168\.(\d{1,3})\.(\d{1,3})\b/ and $1 > 0 and $1 < 100 and $2 < 256; }` [download] I like to do this kind of thing with IP numbers from Socket::inet_aton(), using bitwise ops, but that isn't such an advantage where netmasks don't correspond to the ranges. After Compline, Zaxo	[reply] [d/l] [select]
Re: Match a Range of IP's by DrHyde (Prior) on Sep 30, 2004 at 16:56 UTC
Check out Net::CIDR. You want the `range2cidr` and `cidrlookup` functions.	[reply] [d/l] [select]
Re: Match a Range of IP's by SpanishInquisition (Pilgrim) on Sep 30, 2004 at 17:26 UTC
Regexp::Common::net looks good. See if it's valid and then check the individual octets once you parse it.	[reply]
Re: Match a Range of IP's by runrig (Abbot) on Sep 30, 2004 at 18:13 UTC
If I understand correctly, you just want: `use Socket qw(inet_aton); my $lower = inet_aton("192.168.1.0"); my $upper = inet_aton("192.168.99.255"); while (<DATA>) { chomp; my $ip = inet_aton($_); print "$_\n" if $lower le $ip and $ip le $upper; }` [download]	[reply] [d/l]
Re: Match a Range of IP's by lhoward (Vicar) on Sep 30, 2004 at 18:22 UTC
IMHO, the right way to do this is to convert all the IPs to integers and compare those. Comparing with a RE will work for most common ones, but trying to determine if 144.7.14.2 is betwen 9.0.1.244 and 199.121.5.19 is not well suited for a regular expression. `if((ip2int($iplow)<=ip2int($ip))\ &&(ip2int($ip) <=ip2int($iphigh))){ #... } sub ip2int{ my $ip=shift; my @s=split /\./,$ip return $s[3]+($s[2]+($s[1]+$s[0]256)256)*256; }` [download]	[reply] [d/l]
Re: Match a Range of IP's by si_lence (Deacon) on Sep 30, 2004 at 16:18 UTC
Hello You are using a character class in your match. `[1-99]` means a "1" to "9" and excatly one of it. To select only one or two digit number use somethin like `print "$_\n" if /192\.168\.\d\d?\.\d+/g` [download] si_lence Update: bpphillips is right with his answer (shame on me!), so I changed the description. At least the regex was ok ;-)	[reply] [d/l] [select]
Re^2: Match a Range of IP's by bpphillips (Friar) on Sep 30, 2004 at 16:22 UTC
actually, within a character class, a "-" character indicates a range unless it's at the beginning or the end of the character class	[reply]
Re: Match a Range of IP's by fokat (Deacon) on Sep 30, 2004 at 23:18 UTC
Hi there: This is a task for NetAddr::IP... `perl -MNetAddr::IP -ne 'print "$_ match\n" if NetAddr::IP->new("192.168.1/24")->contains(NetAddr::IP->new($_))'` Best regards -lem, but some call me fokat	[reply] [d/l]
Re^2: Match a Range of IP's by runrig (Abbot) on Sep 30, 2004 at 23:34 UTC
NetAddr::IP->new("192.168.1/24")->contains(NetAddr::IP->new($_)) Except that the CIDR address you have doesn't match the OP's desired range (192.168.1.0-192.168.99.255), so he'd have to run your code up to 99 times to see if the address is in that range. Or just another way (not tested): `use Net::CIDR::Lite; my $range = Net::CIDR::Lite->new("192.168.1.0-192.168.99.255"); while (<DATA>) { chomp; print "$_\n" if $range->find($_); }` [download]	[reply] [d/l]
Re: Match a Range of IP's by Dru (Hermit) on Sep 30, 2004 at 18:02 UTC
Thank you everyone. Alot of good suggestions. I'll have to check each one of them out.	[reply]
Re: Match a Range of IP's by TedPride (Priest) on Oct 01, 2004 at 09:42 UTC
`while (<DATA>) { print if /^192.168.[1-9]\d?.([1-9]\d?\d?)$/ && $1 < 256; }` [download] 1-99 is either one or two digits, with the first digit always being 1 or greater. Then you have to check for a valid 4th pair, which means 1-3 digits with the first being at least 1 and the whole thing being less than 256.	[reply] [d/l]