Bug #17408 for Net-Ping: Net-Ping 2.31 fails to verify source address

Wed Feb 01 04:58:04 2006 Guest - Ticket created

Subject:

Net-Ping 2.31 fails to verify source address

I use Net::Ping 2.31, as downloaded from CPAN, to ping several hosts with ICMP. By the way I use it, I end up with the very same seq number in each packet. Version 2.31 does not verify the source address of the response. This leads me to "phantom" ping, where a device which is switched of and in my drawer sometimes appears to answer, due to previous answers from different hosts. This is frequent when there are large RTTs. The patch I use is a trivial one-liner almost completely taken from a previous version: root@spock:~# diff -c t /usr/lib/perl5/5.8.7/Net/Ping.pm *** t 2006-02-01 10:15:20.000000000 +0100 --- /usr/lib/perl5/5.8.7/Net/Ping.pm 2006-02-01 10:30:49.000000000 +0100 *************** *** 477,482 **** --- 477,483 ---- $self->{"from_type"} = $from_type; $self->{"from_subcode"} = $from_subcode; if (($from_pid == $self->{"pid"}) && # Does the packet check out? + (! $source_verify || (inet_ntoa($from_ip) eq inet_ntoa($ip))) && ($from_seq == $self->{"seq"})) { if ($from_type == ICMP_ECHOREPLY){ $ret = 1; Since I believe this to be the correct behaviour, I humbly suggest that you include it in the next release. Best regards, Bergonz

Tue Jul 31 11:37:44 2007 SMPETERS [...] cpan.org - Correspondence added

On Wed Feb 01 04:58:04 2006, guest wrote: Show quoted text

> I use Net::Ping 2.31, as downloaded from CPAN, to ping several hosts > with ICMP. By the way I use it, I end up with the very same seq number > in each packet. > > Version 2.31 does not verify the source address of the response. This > leads me to "phantom" ping, where a device which is switched of and in > my drawer sometimes appears to answer, due to previous answers from > different hosts. This is frequent when there are large RTTs. > > The patch I use is a trivial one-liner almost completely taken from a > previous version: > > root@spock:~# diff -c t /usr/lib/perl5/5.8.7/Net/Ping.pm > *** t 2006-02-01 10:15:20.000000000 +0100 > --- /usr/lib/perl5/5.8.7/Net/Ping.pm 2006-02-01 10:30:49.000000000

+0100 Show quoted text

> *************** > *** 477,482 **** > --- 477,483 ---- > $self->{"from_type"} = $from_type; > $self->{"from_subcode"} = $from_subcode; > if (($from_pid == $self->{"pid"}) && # Does the packet check out? > + (! $source_verify || (inet_ntoa($from_ip) eq

inet_ntoa($ip))) && Show quoted text

> ($from_seq == $self->{"seq"})) { > if ($from_type == ICMP_ECHOREPLY){ > $ret = 1; > > Since I believe this to be the correct behaviour, I humbly suggest that > you include it in the next release. > > Best regards, > Bergonz

Excellent! This appears to solve the problems with using Net::Ping multi-threaded too! Thanks much for this fix which will be in the next release.

Tue Jul 31 11:37:47 2007 The RT System itself - Status changed from 'new' to 'open'

Mon Aug 06 09:10:48 2007 SMPETERS [...] cpan.org - Correspondence added

On Tue Jul 31 11:37:44 2007, SMPETERS wrote: Show quoted text

> On Wed Feb 01 04:58:04 2006, guest wrote:

> > I use Net::Ping 2.31, as downloaded from CPAN, to ping several hosts > > with ICMP. By the way I use it, I end up with the very same seq number > > in each packet. > > > > Version 2.31 does not verify the source address of the response. This > > leads me to "phantom" ping, where a device which is switched of and in > > my drawer sometimes appears to answer, due to previous answers from > > different hosts. This is frequent when there are large RTTs. > > > > The patch I use is a trivial one-liner almost completely taken from a > > previous version: > > > > root@spock:~# diff -c t /usr/lib/perl5/5.8.7/Net/Ping.pm > > *** t 2006-02-01 10:15:20.000000000 +0100 > > --- /usr/lib/perl5/5.8.7/Net/Ping.pm 2006-02-01 10:30:49.000000000

> +0100

> > *************** > > *** 477,482 **** > > --- 477,483 ---- > > $self->{"from_type"} = $from_type; > > $self->{"from_subcode"} = $from_subcode; > > if (($from_pid == $self->{"pid"}) && # Does the packet check

out? Show quoted text

> > + (! $source_verify || (inet_ntoa($from_ip) eq

> inet_ntoa($ip))) &&

> > ($from_seq == $self->{"seq"})) { > > if ($from_type == ICMP_ECHOREPLY){ > > $ret = 1; > > > > Since I believe this to be the correct behaviour, I humbly suggest that > > you include it in the next release. > > > > Best regards, > > Bergonz

> > > Excellent! This appears to solve the problems with using Net::Ping > multi-threaded too! Thanks much for this fix which will be in the next > release.

This patch was included in version 2.33. Thanks!

Mon Aug 06 09:10:51 2007 SMPETERS [...] cpan.org - Status changed from 'open' to 'resolved'

Mon Aug 06 09:11:27 2007 SMPETERS [...] cpan.org - Reference by ticket #4170 added