#!/usr/bin/perl use strict; use warnings; use English; use Data::Dumper; # Set these for your remote host... my $user = "user"; my $password = "password"; my $host = "machine"; # Time to wait for remote command to finish... my $timeout=10; # Consider upping this if you change $high # Remote command... my $cmd = "cat"; # Print heading... print "Net::SSH::Perl bug test...\n"; print "host=$host user=$user remoteCmd=$cmd\n"; # Set variables... my $high=932779; # Maximum number of starting xmitChars my $low=0; my $i=$high; my $delta=$high-$low;; my $ssh; # Main loop... while($delta>1) { undef($ssh); print "xferChars=$i"; # setup SSH... $ssh = newssh() || die "Can't create a new ssh, exiting..."; print '|'; # Indicates newssh worked... $ssh->login($user,$password) || die "Can't login, exiting..."; print '-'; # Indicates successful login... # Proper values of $i will trigger the bug... my $stdin = '=' x $i; # Run remote command... my ($stdout, $stderr, $exit) = runcmd($ssh, $cmd, $stdin, $timeout); # Check output... if(defined($stdout)) { if(length($stdout) != $i) { die "Data mismatch, expected: $i chars, got: ", length($stdout), "chars\n"; } # Go back up... $delta = $high-$i; $low = $i; $i += int($delta/2); print "OK, back up to $i chars\n" }else{ # Go down... $delta = $i-$low; $high = $i; $i -= int($delta/2); print "Error, down to $i chars\n\t$stderr\n"; next; } } if ($i == $high) { print "\nBug did not trigger with $high chars on this system.\n"; }else{ print "\nReport for remote host: $host...\n"; print "xferChars=$low works, xferChars=$high hangs on timeout=$timeout.\n"; } print "exiting...\n"; sub newssh { my $ssh; # Require the correct SSH package, based on OS... if($OSNAME=~/^(MSWin32)/) { require Net::SSH::W32Perl; $ssh = Net::SSH::W32Perl->new( $host, port => 22 , protocol => 2, #debug => 999, ); }else{ require Net::SSH::Perl; $ssh = Net::SSH::Perl->new( $host, port => 22 , protocol => 2, #debug => 999, ); } return($ssh); } sub runcmd { my $ssh = shift || die "Missing ssh object"; my $cmd = shift || die "Missing cmd"; my $stdin = shift || die "Missing stdin"; my $timeout = shift || die "Missing timeout"; my ($stdout, $stderr, $exit); eval { local $SIG{'ALRM'} = sub { die "alarm handler $timeout second timeout"; }; alarm($timeout); ($stdout, $stderr, $exit) = $ssh->cmd($cmd, $stdin); alarm(0); }; if($@) { $stderr=$@; $stderr=~s/( at |\n).*$/ /s; } return ($stdout, $stderr, $exit); }

Net::SSH::Perl bug test... host=nwsgpb user=watchmrk remoteCmd=cat xferChars=932779|-Error, down to 466390 chars Received disconnect message: Corrupted MAC on input. xferChars=466390|-Error, down to 233195 chars Received disconnect message: Corrupted MAC on input. xferChars=233195|-Error, down to 116598 chars Received disconnect message: Corrupted MAC on input. xferChars=116598|-Error, down to 58299 chars Received disconnect message: Corrupted MAC on input. xferChars=58299|-Error, down to 29150 chars alarm handler 10 second timeout xferChars=29150|-Error, down to 14575 chars alarm handler 10 second timeout xferChars=14575|-Error, down to 7288 chars alarm handler 10 second timeout xferChars=7288|-OK, back up to 10931 chars xferChars=10931|-OK, back up to 12753 chars xferChars=12753|-Error, down to 11842 chars alarm handler 10 second timeout xferChars=11842|-Error, down to 11387 chars alarm handler 10 second timeout xferChars=11387|-OK, back up to 11614 chars xferChars=11614|-Error, down to 11501 chars alarm handler 10 second timeout xferChars=11501|-OK, back up to 11557 chars xferChars=11557|-Error, down to 11529 chars Received disconnect message: Corrupted MAC on input. xferChars=11529|-OK, back up to 11543 chars xferChars=11543|-Error, down to 11536 chars Received disconnect message: Corrupted MAC on input. xferChars=11536|-Error, down to 11533 chars alarm handler 10 second timeout xferChars=11533|-OK, back up to 11534 chars xferChars=11534|-OK, back up to 11535 chars xferChars=11535|-OK, back up to 11535 chars Report for remote host: nwsgpb... xferChars=11535 works, xferChars=11536 hangs on timeout=10. exiting...