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hi

i need to verify if an ip-address falls inside a range for example,
say 10.1.1.1 to 10.1.2.255.
So if a user keys in 10.1.2.2, it should fall inside this range and
then the program can do something.

How can i go about declaring the range, and how can i check the ip
whether it falls inside the range. ?
thanks.

In article <> ,
mike <> wrote:
:i need to verify if an ip-address falls inside a range for example,
:say 10.1.1.1 to 10.1.2.255.
:So if a user keys in 10.1.2.2, it should fall inside this range and
:then the program can do something.

:How can i go about declaring the range, and how can i check the ip
:whether it falls inside the range. ?

for each of the three IP addresses, split the IP address on '\.',
say into @ipd; then
$iaddr = pack('C4', $ipd[0], $ipd[1], $ipd[2], $ipd[3]);
gives the binary equivilent of the IP. Once you have all three,
it's just a matter of testing that the test ip is numerically
between the other two values.
--
"No one has the right to destroy another person's belief by
demanding empirical evidence." -- Ann Landers

mike wrote:
> i need to verify if an ip-address falls inside a range for example,
> say 10.1.1.1 to 10.1.2.255.

One idea:

my $test = '10.1.2.2';
my $lower = '10.1.1.1';
my $higher = '10.1.2.255';

sub iptest {
my @ip = @_;
for ( @ip ) {
$_ = join '', map { sprintf '%03s', $_ } split /\./, $_;
}
$ip[0] >= $ip[1] and $ip[0] <= $ip[2] ? 1 : 0;
}

if ( iptest($test, $lower, $higher) ) {
print "$test falls inside the range $lower to $higher.\n";
}

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

(Walter Roberson) wrote:
> In article <> ,
> mike <> wrote:
> :i need to verify if an ip-address falls inside a range for example,
> :say 10.1.1.1 to 10.1.2.255.
> :So if a user keys in 10.1.2.2, it should fall inside this range and
> :then the program can do something.
>
> :How can i go about declaring the range, and how can i check the ip
> :whether it falls inside the range. ?
>
> for each of the three IP addresses, split the IP address on '\.',
> say into @ipd;

Or, better, use Regexp::Common.

Ben

--
And if you wanna make sense / Whatcha looking at me for? (Fiona Apple)
* *

>> On 29 Jan 2004 18:43:28 -0800,
>> (mike) said:

> hi i need to verify if an ip-address falls inside a range
> for example, say 10.1.1.1 to 10.1.2.255. So if a user keys
> in 10.1.2.2, it should fall inside this range and then the
> program can do something.

> How can i go about declaring the range, and how can i check
> the ip whether it falls inside the range. ? thanks.

http://search.cpan.org/

Take a look at NetAddr::IP and Net::IP::Match, one or both
might do what you want.

hth
t

mike wrote:
> hi
>
> i need to verify if an ip-address falls inside a range for example,
> say 10.1.1.1 to 10.1.2.255.
> So if a user keys in 10.1.2.2, it should fall inside this range and
> then the program can do something.
>
> How can i go about declaring the range, and how can i check the ip
> whether it falls inside the range. ?
> thanks.


#!/usr/bin/perl
use strict;
use warnings;
use IO::Socket qw(inet_aton);


my @ip_range = qw{ 10.1.1.1 10.1.2.255 };
my ($lower, $upper) = map { inet_aton($_) } @ip_range;


for ( qw{ 10.1.2.2 10.1.2.10 10.1.3.222 } ) {
my $packed_ip = inet_aton($_);
if ( $packed_ip lt $lower or $packed_ip gt $upper ) {
print "$_ is out of expected range ",
"$ip_range[0] .. $ip_range[1].\n";
next;
}


print "$_ is in range.\n";
}


--
Kien

Kien Ha <> wrote in message news:<RCkSb.6281$ ble.rogers.com>...
> mike wrote:
> > hi
> >
> > i need to verify if an ip-address falls inside a range for example,
> > say 10.1.1.1 to 10.1.2.255.
> > So if a user keys in 10.1.2.2, it should fall inside this range and
> > then the program can do something.
> >
> > How can i go about declaring the range, and how can i check the ip
> > whether it falls inside the range. ?
> > thanks.
>
>
> #!/usr/bin/perl
> use strict;
> use warnings;
> use IO::Socket qw(inet_aton);
>
>
> my @ip_range = qw{ 10.1.1.1 10.1.2.255 };
> my ($lower, $upper) = map { inet_aton($_) } @ip_range;
>
>
> for ( qw{ 10.1.2.2 10.1.2.10 10.1.3.222 } ) {
> my $packed_ip = inet_aton($_);
> if ( $packed_ip lt $lower or $packed_ip gt $upper ) {
> print "$_ is out of expected range ",
> "$ip_range[0] .. $ip_range[1].\n";
> next;
> }
>
>
> print "$_ is in range.\n";
> }




Thanks for all the tips...appreciate that..

In article <RCkSb.6281$ ogers.com>,
Kien Ha <> wrote:
:mike wrote:
:> i need to verify if an ip-address falls inside a range for example,

:use IO::Socket qw(inet_aton);

Looking at perldoc, it appears to me that should be Socket instead
of IO::Socket .


: my $packed_ip = inet_aton($_);
: if ( $packed_ip lt $lower or $packed_ip gt $upper ) {

I realized a potential flaw in my pack 'C4' version:
I was using network byte order and numeric comparisions, which
would fail on small-endian or machines with other unusual binary
storage orders. I see that your version avoids that by doing
string comparisons instead of numeric comparisons. Think I'll
go edit some of my code now...
--
We don't need no side effect-ing
We don't need no scope control
No global variables for execution
Hey! Did you leave those args alone? -- decvax!utzoo!utcsrgv!roderick

In article <bvfbsl$3g6$>,
Walter Roberson <> wrote:
|In article <RCkSb.6281$ ogers.com>,
|Kien Ha <> wrote:

|: my $packed_ip = inet_aton($_);
|: if ( $packed_ip lt $lower or $packed_ip gt $upper ) {

|I realized a potential flaw in my pack 'C4' version:
|I was using network byte order and numeric comparisions, which
|would fail on small-endian or machines with other unusual binary
|storage orders. I see that your version avoids that by doing
|string comparisons instead of numeric comparisons.

Ah, and I just found a theoretical flaw in the inet_aton version.
The documentation for inet_aton says that it returns an
opaque string, and that one should not assume that it is 32 bits
(e.g., because of IPv6.) Theoretically, then, the results of
inet_aton are not always going to be linear for lt / gt purposes,
even if the inputs are consistantly dotted quads.
--
Oh, yeah, an African swallow maybe, but not a European swallow.
That's my point.

Walter Roberson wrote:
> Ah, and I just found a theoretical flaw in the inet_aton version.
> The documentation for inet_aton says that it returns an opaque
> string, and that one should not assume that it is 32 bits (e.g.,
> because of IPv6.) Theoretically, then, the results of inet_aton are
> not always going to be linear for lt / gt purposes, even if the
> inputs are consistantly dotted quads.

So why not keep it simple, then?

http://groups.google.se/groups?selm=....uni-berlin.de



--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl