Linux repeater mod

[lall]

Hi,

chunkrepeater.pl is a modified version of ultravnc_repeater.pl
chunkrepeater.pl is very easy to use and run. Just make it executable (4) and double click it to run in default mode!

Complete how-to:
I use console to explain the process, because there may be differences in different OS builds, but console stays quite the same.
You can basically copy-paste those commands to your console.

Open your console/terminal and write:

1)Download script

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wget http://www.chunkvnc.com/extras/lall/chunkrepeater.tar.gz

This will download the script to your home directory.

2)Unpack it:

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tar xvfz chunkrepeater.tar.gz

3)Move it where you want it to be (optional):
Tip! Use TAB to finish your commands.

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mv chunkrepeater/ /path/you/want-it-to-be/

(for example: mv chunkrepeater/ /srv/)

4)Make it executable!

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sudo chmod +x chunkrepeater/chukrepeater.pl

OR if you moved it

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sudo chmod +x /path/to/script/chunkrepeater.pl

That's it! Now the script is ready to run!

###########################

How to use the script:

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sudo /path/to/script/chunkrepeater.pl [-b -w] [-r] [server port] [viewer port]

All [arguments] are optional!

-w runs script in whitelist mode
-b runs script in blacklist mode
-r refuses existing IDs

To kill/stop the script:

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sudo killall -p chunkrepeater.pl

Log file will be created in:
/var/log/chunkrepeater.log

Download:
http://www.chunkvnc.com/extras/lall/

Changes:
script has IP logging
script runs always as system daemon (no need to use CHUNKREPEATER_LOOP=BG)
script always creates log file to /var/log/ (no need to use CHUNKREPEATER_LOGFILE=/pathtologfile.log)
script has three operating modes - normal, whitelist and blacklist.

Tips:
edit chunkrepeater.pl with any text editor and change 10101 and 10102 ports as you need them to be! with so, you can simply start the script without entering your server and viewer ports! (chunkrepeater -w 5900 5901)

To switch between operating modes you must kill the script first and then run it in different mode.


Still working on other mods and security.

[maxabbr]

Thanks lall, great tip and explanation about the repeater configuration on Linux.

[supercoe]

Wow, great tips and first post!

Welcome lall, I hope you stick around.

[JonD]

I use the repeater from
http://koti.mbnet.fi/jtko/
and auto start it with my linux box bootup.

Is there anyone that can compare the perl script with the above application to show the relative merits of each repeater?

The one feature that I do use... a restriction on what IDs are permitted to pass through the repeater.

JonD

[redge]

lall,

you welcome
please, merge your effort together with others coders
[topic=18035][/topic]

http://code.google.com/p/uvncrepeater/

[lall]

I use the repeater from
http://koti.mbnet.fi/jtko/
and auto start it with my linux box bootup.

Is there anyone that can compare the perl script with the above application to show the relative merits of each repeater?

The one feature that I do use... a restriction on what IDs are permitted to pass through the repeater.

JonD

JonD,

This Jari's code is quite old. But it works, I've used it before.

If you'd like, I may edit the perl script so, that there would be a blacklist file for IP addresses and ID numbers. This was in my todo list, because I have some InstantSupport exes installed as services, and I have no idea where they are..and it sounds like fun

[lall]

lall,

you welcome
please, merge your effort together with others coders
[topic=18035][/topic]

http://code.google.com/p/uvncrepeater/

I will digest the information that's available. Thanks for link.

[JonD]

lall,

A modified script to restrict to specified IDs would be great. Since most everyone here seems to be using the Perl script, I think I would like to switch.

JonD

[lall]

I'll do necessary modifications and post complete modified script with complete how-to.
Since it's Christmas (happy holidays to all) it's gonna take me some time.
And since I'm not a programmer or a developer, the process may be slower than it's for some qualified perl-philologist

[supercoe]

I agree that the Perl repeater would be the best one to work on.

Looking forward to see what you do here.


Wishlist:

- Simple authentication before allowing an ID to connect
- Ability to see currently connected ID's (rudi did this in a test build of the Windows repeater with a built in http server)


I'm new to Perl as well but I'd really like to help in any way I can since repeater security is often requested.

Happy holidays.

[lall]

lall,

A modified script to restrict to specified IDs would be great. Since most everyone here seems to be using the Perl script, I think I would like to switch.

JonD

Have you tried the script already? I'd like to get (any) comments.

[redge]

i can't check, i have a linux server but i'm not techncian of linux, i'm just lammer, and the repeater is installed is based on the repeater linux 0.14

[lall]

i can't check, i have a linux server but i'm not techncian of linux, i'm just lammer, and the repeater is installed is based on the repeater linux 0.14

0.14 is old..i'd really recommend you to switch.
You and lammer? I hardly believe..

If you'd like test the repeater and need help, I can help you out.

What is your server OS? Debian based? Or centOS?

if it's centos, i must create new virtual machine to test the script, since i have never used centOS before..although i imagine that it's not a problem for me. I am usng debian based linux distros.

Should I write complete how-to for downloading, unpacking and using the script so everyone can understand it?

[redge]

would be happy to know the list change log of repeater before request update repeater on my linux virtual server

i'm owner of the virtual server based Debian linux but not technician of linux
i'm experienced user of windows not linux

[lall]

would be happy to know the list change log of repeater before request update repeater on my linux virtual server

i'm owner of the virtual server based Debian linux but not technician of linux
i'm experienced user of windows not linux

Let me know if you need help, maybe i can help.

[lall]

Before I'm diving to security, i'm splitting the code into 2:
GUI mode and verbose mode.

If all goes well, the script will run in GUI by default and in verbose mode from command line.

[Rat]

Although I've already mentioned this point to Lall privately I thought I should repeat it publicly here now that there's a forum thread.

I use the Perl repeater on shared hosting environments where the user has only limited privileges and the BG Loop mode allowed it to run effectively as a daemon. A GUI would also be of limited use in this scenario unless it provided a Web interface which woud be great and was something that I have also considered.

I can only reiterate Supercoe's comment that the ability to provide security to the script would be my highest priority too.

I also recently suggested a mod to add IP address logging, see the code below:

IP ADDRESS LOGGING MOD
In the code where it has: lprint("new vnc client connecting."); and lprint("new vnc server connecting."); add some other lprint commands like the following:

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if ($client_listen) {lprint($client_listen->sockhost ());}
else if ($client_listen6) {lprint($client_listen6->sockhost ());}

and

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if ($server_listen) {lprint($server_listen->sockhost ());}
else if ($server_listen6) {lprint($server_listen6->sockhost ());}

This should log the Client and Server IP address in the log file.

Note: See http://perldoc.perl.org/IO/Socket/INET.html[/u]

[lall]

Hi rat,

Actually, I added IP logging to the point where the server gets an ID.

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lprint("storing new vnc server with ID:$id from " . $sock->peerhost);

But i'll add it before that point too, thanks for info.

[lall]

A GUI would also be of limited use in this scenario unless it provided a Web interface which would be great and was something that I have also considered.

If you can tell me how to create PHP based UI for the script without local webserver, I'll do it. I searched and experimented, but didn't had success..
So far the easiest (for users) is to write Tk UI in to the script and IF users are really unable to install perl-tk, they can always run the script in verbose mode, without needing to install anything.

You asked how did I manage to run the scrip as sys daemon:

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#Daemon stuff
setpgrp(0, 0);
my $pid = fork();

	if (! defined $pid) {
	die "chunkrepeater.pl: $!\n";
	} elsif ($pid) {
	wait;
	exit 0;
	}
	if (fork) {
		exit 0;
	}
	setpgrp(0, 0);
	close STDIN;
	if (! $ENV{CHUNKREPEATER_LOGFILE}) {
		close STDOUT;
		close STDERR;
	}
	if (exists $ENV{CHUNKREPEATER_PIDFILE}) {
		open_pidfile();
	}

if (exists $ENV{CHUNKREPEATER_PIDFILE}) {
	open_pidfile();
}

# End of background/daemon stuff

This is original code from original ultravnc_repeater.pl, I just ripped out what wasn't needed. This should run even without superuser privileges.

[naftali5]

A GUI would also be of limited use in this scenario unless it provided a Web interface which would be great and was something that I have also considered.

If you can tell me how to create PHP based UI for the script without local webserver, I'll do it. I searched and experimented, but didn't had success..
So far the easiest (for users) is to write Tk UI in to the script and IF users are really unable to install perl-tk, they can always run the script in verbose mode, without needing to install anything.

How about simply modfying the pl script to maintain a single file, in a sensible format, of all current server connections, all viewer connections, along with if they are bridged, and connection information (ip, id, and anything else you have). This will allow integration of a read-only UI from any programming language. I don't specifcally need it to be linux, but this feature (ability to view/retrieve a list of current connections) is noticably lacking in every implementation of repeater that i have seen.

[lall]

A GUI would also be of limited use in this scenario unless it provided a Web interface which would be great and was something that I have also considered.

If you can tell me how to create PHP based UI for the script without local webserver, I'll do it. I searched and experimented, but didn't had success..
So far the easiest (for users) is to write Tk UI in to the script and IF users are really unable to install perl-tk, they can always run the script in verbose mode, without needing to install anything.

How about simply modfying the pl script to maintain a single file, in a sensible format, of all current server connections, all viewer connections, along with if they are bridged, and connection information (ip, id, and anything else you have). This will allow integration of a read-only UI from any programming language. I don't specifcally need it to be linux, but this feature (ability to view/retrieve a list of current connections) is noticably lacking in every implementation of repeater that i have seen.

Hi,

I've considered this option too. But.
Right now my plans are to write live connections monitoring in to the repeater but without GUI. In that case you can use the repeater in headless server without graphical manager and still get the information as txt files. And I'll write separate GUI controller (in perl, for now) for the repeater that collects data (logs, live connections) from text files. This is really good way, because you can always write other GUIs for the repeater (php, or whatever is needed). This will make repeater to be independent from GUIs and gives a lot flexibility for users.

[supercoe]

+1 for the GUI being separate, Rudi has similar ideas for UltraVNC v2.

[stinson6016]

Have been using chunkrepeater at work the past week using a php log file viewer with success. every thing seems to work well