Question

I was mind altered, and was trying to configure munin plugin on ubuntu server. I pasted Perl code in terminal as bash – and each line of code ran as a command.

Is perl syntax different enough to not have caused any damage or unintended changes to server?

Here is the code (btw, it did create two folders in my home directory that’s why Im worried):

I wonder if I unintentionally messed up something :S

#!/usr/bin/perl
#
# Plugin to monitor the number of accesses to Apache servers. It handles
# a list of ports passed in from a plugin configuration file.
#
# Requirements:
#   - Needs access to http://localhost/server-status?auto (or modify the
#     address for another host). See your apache documentation on how to
#     set up this url in your httpd.conf. Apache needs ExtendedStatus
#     enabled for this plugin to work
#
# Tip: To see if it's already set up correctly, just run this plugin
# with the parameter "autoconf". If you get a "yes", everything should
# work like a charm already.
#
# Parameters supported:
#
#   config
#   autoconf
#
# Configurable variables
#
#   url      - Override default status-url
#   port     - HTTP port numbers
#
#   ssl      - activate SSL (add env.ssl yes in munin plugin configuration)
#   urls     - Override default status-url (SSL)
#   ports    - HTTPS port numbers (SSL)
#
# $Log$
# Revision 1.13  2006/03/07 20:30:00 fra519
# adapt script for Apache-SSL Server.
#
# Revision 1.12  2004/12/10 18:51:43  jimmyo
# linux/apt* has been forced to LANG=C, to get predictable output.
#
# Revision 1.11  2004/12/10 10:47:47  jimmyo
# Change name from ${scale} to ${graph_period}, to be more consistent.
#
# Revision 1.10  2004/12/09 22:12:54  jimmyo
# Added "graph_period" option, to make "graph_sums" usable.
#
# Revision 1.9  2004/09/26 22:14:39  jimmyo
# Changd COUNTER -> DERIVE for some plugins. Set min/max values.
#
# Revision 1.8  2004/05/20 13:57:11  jimmyo
# Set categories to some of the plugins.
#
# Revision 1.7  2004/05/14 21:16:46  jimmyo
# "Upped" som plugins from contrib/manual to auto.
#
# Revision 1.6  2004/04/27 21:32:06  jimmyo
# Clarified the vlabels in the apache-plugins (Deb#238594).
#
# Revision 1.5  2004/04/27 08:46:57  jimmyo
# Fixed broken autoconf in apache-* plugins (Deb#236144).
#
# Revision 1.4  2004/02/18 15:47:35  jimmyo
# The generic/apache_* plugins now have defined max values.
#
# Revision 1.3  2004/02/03 17:17:25  jimmyo
# Generic/apache-plugins have been modified to properly to report the correct autoconf value. Also, bugfixes in _processes and _volume.
#
# Revision 1.2  2004/01/29 18:47:30  jimmyo
# Made plugins apache_* compatible with older versions of LWP::UserAgent (SF#881411).
#
# Revision 1.1  2004/01/02 18:50:00  jimmyo
# Renamed occurrances of lrrd -> munin
#
# Revision 1.1.1.1  2004/01/02 15:18:07  jimmyo
# Import of LRRD CVS tree after renaming to Munin
#
# Revision 1.4  2003/12/18 16:35:33  jimmyo
# fail more gracefully when using uninstalled perl modules.
#
# Revision 1.3  2003/11/07 17:43:16  jimmyo
# Cleanups and log entries
#
#
#
# Magic markers:
#%# family=auto
#%# capabilities=autoconf

my $ret = undef;
my $ssl = undef;

if (! eval "require LWP::UserAgent;")
{
    $ret = "LWP::UserAgent not found";
}
if (! eval "require Crypt::SSLeay;" and exists $ENV{'ssl'})
{
    $ssl = "Crypt::SSLeay not found";
}

my $URL = exists $ENV{'url'} ? $ENV{'url'} : "http://127.0.0.1:%d/server-status?auto";
my @PORT = exists $ENV{'port'} ? split(' ', $ENV{'port'}) : (80);

my $URLS = exists $ENV{'urls'} ? $ENV{'urls'} : "https://127.0.0.1:%d/server-status?auto";
my @PORTS = exists $ENV{'ports'} ? split(' ', $ENV{'ports'}) : (443);

if ( exists $ARGV[0] and $ARGV[0] eq "autoconf" )
{
    if ($ret)
    {
        print "no ($ret)\n";
        exit 1;
    }

    if ($ssl) {
        print "no ($ssl)\n";
        exit 1;
    }

    my $ua = LWP::UserAgent->new(timeout => 30);

    my @badports;
    foreach my $port (@PORT) {
        my $url = sprintf $URL, $port;
        my $response = $ua->request(HTTP::Request->new('GET',$url));
        push @badports, $port unless $response->is_success and $response->content =~ /^Total Accesses:/im;
    }
    if (exists $ENV{'ssl'}) {
        foreach my $port (@PORTS) {
            my $url = sprintf $URLS, $port;
            my $response = $ua->request(HTTP::Request->new('GET',$url));
            push @badports, $port unless $response->is_success and $response->content =~ /^Total Accesses:/im;
        }
    }
    if (@badports) {
        print "no (no apache server-status or ExtendedStatus missing on ports @badports)\n";
        exit 1;
    } else {
        print "yes\n";
        exit 0;
    }
}

if ( exists $ARGV[0] and $ARGV[0] eq "config" )
{
    print "graph_title Apache accesses\n";
    print "graph_args --base 1000\n";
    print "graph_vlabel accesses / \${graph_period}\n";
    print "graph_category apache\n";
    foreach my $port (@PORT) {
        print "accesses$port.label port $port\n";
        print "accesses$port.type DERIVE\n";
        print "accesses$port.max 1000000\n";
        print "accesses$port.min 0\n";
    }
    if (exists $ENV{'ssl'}) {
        foreach my $port (@PORTS) {
            print "accesses$port.label port $port\n";
            print "accesses$port.type DERIVE\n";
            print "accesses$port.max 1000000\n";
            print "accesses$port.min 0\n";
        }
    }
    exit 0;
}

my $ua = LWP::UserAgent->new(timeout => 30);

foreach my $port (@PORT) {
    my $url = sprintf $URL, $port;
    my $response = $ua->request(HTTP::Request->new('GET',$url));
    if ($response->content =~ /^Total Accesses:\s+(.+)$/im) {
        print "accesses$port.value $1\n";
    } else {
        print "accesses$port.value U\n";
    }
}

if (exists $ENV{'ssl'}) {
    foreach my $port (@PORTS) {
        my $url = sprintf $URLS, $port;
        my $response = $ua->request(HTTP::Request->new('GET',$url));
        if ($response->content =~ /^Total Accesses:\s+(.+)$/im) {
            print "accesses$port.value $1\n";
        } else {
            print "accesses$port.value U\n";
        }
    }
}
# vim:syntax=perl

Answer 1

The comments will be ignored. I originally meant the Perl comments. Looks like I will have to ignore downvotes as I help you out here 🙂

I have pasted the command into a bash shell of a vanilla Ubuntu desktop install. Downvoters will (not unreasonably) think this a bad idea for a whole host of reasons.

My attitude is I have a spare Ubuntu Virtual Machine available to test this so I am happy to destroy it if anything bad happens to it. A cursory visual inspection of the code reveals the following.

Do you have a command call my? If not then the following code is clear of mines.

my $ret = undef;
my $ssl = undef;

if (! eval "require LWP::UserAgent;")


if (! eval "require Crypt::SSLeay;" and exists $ENV{'ssl'})
{
    $ssl = "Crypt::SSLeay not found";
}

my $URL = exists $ENV{'url'} ? $ENV{'url'} : "http://127.0.0.1:%d/server-status?auto";
my @PORT = exists $ENV{'port'} ? split(' ', $ENV{'port'}) : (80);

my $URLS = exists $ENV{'urls'} ? $ENV{'urls'} : "https://127.0.0.1:%d/server-status?auto";
my @PORTS = exists $ENV{'ports'} ? split(' ', $ENV{'ports'}) : (443);

Following on we have

if ( exists $ARGV[0] and $ARGV[0] eq "autoconf" )
{
  if ($ret)
  {
      print "no ($ret)\n";
      exit 1;
  }

if ($ssl) {
    print "no ($ssl)\n";
    exit 1;

The exit 1 would have taken you out of the current shell.

Assuming that you were in a sub shell more analysis to follow …

So here is the interesting code.

rkielty@ubuntu:~$ foreach my $port (@PORT) {
bash: syntax error near unexpected token `('

Clear of mines

rkielty@ubuntu:~$     push @badports, $port unless $response->is_success and $response->content =~ /^Total Accesses:/im;
The program 'push' is currently not installed.  You can install it by typing:
sudo apt-get install heimdal-clients

Now here you will have to check to see if you have a push program and see what it does.

run which push then man or info push

rkielty@ubuntu:~$         print "no (no apache server-status or ExtendedStatus missing on ports @badports)\n";
Warning: unknown mime-type for "no (no apache server-status or ExtendedStatus missing on ports @badports)\n" -- using "application/octet-stream"
Error: no such file "no (no apache server-status or ExtendedStatus missing on ports @badports)\n"

So here we are protected by the error.

Following on from there there are two invocations of exit.

So it’s looks like you probably should be fine.

The caveats are that you need to ensure that there are no programs called my or push on your system

I’m not sure how the directories would have been created and you should probably investigate that further. Remember they may not have been caused by this.