NamHuy

Log4Tailer 2.0 released with SSH tailing capabilities

Huy Tran — Tue, 23 Feb 2010 15:15:44 +0000

Log4Tailer 2.0 http://code.google.com/p/log4tailer/ has just been released. It has been a month of some thought and testing the feasability of including tailing over SSH, and this release provides just that. It will open the door for a range of more features to control remote logs scattered across a network from a single terminal, instead of having multiple terminals or windows opened. As always, the project provides a nice pdf UserGuide explaining the ssh tailing capabilities of log4tailer.

Ubuntu Karmik and Eclipse Galileo

Huy Tran — Mon, 11 Jan 2010 21:46:45 +0000

The great Ubuntu Karmik is just around the corner. If you happen to use Eclipse from the official eclipse webpage and you see that some eclipse buttons do not work, then apply the following hack. Make yourself a one line script to execute eclipse like follows:

#!/bin/bash

export GDK_NATIVE_WINDOWS=1
./eclipse

and it will work again. For tptp (the profiling tools for eclipse) you’ll need libstdc++5 package from debian.

Ubuntu Linux enable telnet service

Huy Tran — Tue, 03 Nov 2009 20:14:10 +0000

Q. How do I install and start telnet service / server under Ubuntu Linux?

A. Telnet is an insecure service. It is recommended that you use ssh service. However sometime telnet server or service is needed. Here are instructions to enable telnet:
Install telnetd server

$ sudo apt-get install telnetd
Restart inetd service:
$ sudo /etc/init.d/openbsd-inetd restart
You should now be able to telnet to the server from Windows or Linux desktop system to Ubentu Linux telnet server. Type the following command to connect to Telnet server:
$ telnet ubentu-linux-server-ip
$ telnet 192.168.1.200
$ telnet ubentu.mydomain.com

Linux Security Hole Goes Back Eight Years

Huy Tran — Sun, 23 Aug 2009 23:20:07 +0000

Here’s another deep chink in the armor of the braindead zealots who claim Linux is inherently more secure than Windows. Julien Tinnes and Tavis Ormandy have found what could be the widest ranging vulnerability yet discovered in the Linux kernel.

Affected versions include all Linux 2.4 and2.6 versions since May 2001. This spans 2.4.4 up to and including 2.4.37.4 in the 2.4 kernel and every iteration of 2.6 from 2.6.0 up to and including 2.6.30.4.

What is this vulnerability all about? Functions in certain kernel routines are left uninitialized, so pointers aren’t validated before dereferencing. This allows local execution of code (sample POC available in both articles linked above) which compromises the machine. Compromise? Yes, pwnt.

These are known affected modules according to Redhat’s bugzilla:
ipx.ko
irda.ko
x25.ko
ax25.ko
bluetooth.ko
sctp.ko
pppoe.ko
pppox.ko
appletalk.ko

That thread offers mitigation possibilities (and some commenters — see #32 and #48 — explain why those steps won’t work). According to post #27 in that thread, the exploit is already being used (as of about a week ago as I write this) to attack machines: “They entered the system through a web application exploit and then used the exploit to gain a root shell.”

This gets to the bigger problems of security. If you think of Linux as only the kernel or even the kernel plus the utilities that make it a functioning operating system, you’re seeing only one layer of vulnerability. Add another layer of complexity with various software and you’re adding more complexity and, accordingly exponentially more layers of vulnerability. If someone can get in through one door, he can often find “keys” to open other doors. That in a nutshell is what happens in cases like #27 in the Redhat bugzilla thread.

Fedora, Debian, and Ubuntu have reportedly already patched for this kernel issue.

Ubuntu 9.04 (Jaunty Jackalope) Final

Huy Tran — Fri, 24 Apr 2009 02:45:10 +0000

Ubuntu is a community developed, linux-based operating system that is perfect for laptops, desktops and servers. It contains all the applications you need – a web browser, presentation, document and spreadsheet software, instant messaging and much more. Ubuntu is free software. Whether you use it at home, at school or at work Ubuntu contains all the applications you’ll ever need, from word processing and email applications, to web server software and programming tools.

Ubuntu is and always will be free of charge. You do not pay any licensing fees. You can download, use and share Ubuntu with your friends, family, school or business for absolutely nothing. We issue a new desktop and server release every six months. That means you’ll always have the the latest and greatest applications that the open source world has to offer. Everything you need on one CD, which provides a complete working environment. Additional software is available online.

Ubuntu comes with full commercial support from Canonical and hundreds of companies around the world. Ubuntu includes the very best translations and accessibility infrastructure that the free software community has to offer. Ubuntu CDs contain only free software applications; we encourage you to use free and open source software, improve it and pass it on.

With Ubuntu Desktop Edition you can surf the web, read email, create documents and spreadsheets, edit images and much more. Ubuntu has a fast and easy graphical installer right on the Desktop CD. On a typical computer the installation should take you less than 25 minutes. The graphical installer enables you to get up and running quickly and easily. On the desktop you have a full set of productivity, internet, drawing and graphics applications, and games.

The Server Edition – built on the solid foundation of Debian which is known for its robust server installations — has a strong heritage for reliable performance and predictable evolution. As your business grows, so does your network. More applications need to be deployed and more servers are required. Ubuntu Server Edition offers support for several common configurations, and simplifies common Linux server deployment processes. It provides a well-integrated platform enabling you to quickly and easily deploy a new server with any of the standard internet services: mail, web, DNS, file serving or database management. A key lesson from its Debian heritage is that of security by default. The Ubuntu Server has no open ports after the installation and contains only the essential software needed to build a secure server.

Link : Ubuntu 9.04 (Jaunty Jackalope) Final

HOWTO: Recording audio cds with K3b

Huy Tran — Mon, 09 Mar 2009 09:38:23 +0000

k3b cannot deal with mp3 files by default in Ubuntu Edgy Eft.
If you need to produce an audio cd by adding mp3 files with k3b, you’ll need to install the following package:
sudo apt-get install libk3b2-mp3
and you are done!!

HowTo Ubuntu 8.10 64bit and Areca 6.2 (6.1) java Backup Utility

Huy Tran — Tue, 17 Feb 2009 08:01:23 +0000

1) Go to Synaptic and install

libswt-cairo-gtk-3.4-jni
libswt-gnome-gtk-3.4-jni
libswt-gtk-3.4-java
libswt-gtk-3.4-jni
libswt-mozilla-gtk-3.4-jni

2) cd /usr/lib/jni

cp the files:

libswt-atk-gtk-3448.so
libswt-cairo-gtk-3448.so
libswt-gtk-3448.so
libswt-pi-gtk-3448.so
libswt-awt-gtk-3448.so
libswt-gnome-gtk-3448.so
libswt-mozilla-gtk-3448.so

to the areca/lib folder with names in order of appearance:

libswt-atk-gtk-3232.so
libswt-cairo-gtk-3232.so
libswt-gtk-3232.so
libswt-pi-gtk-3232.so
libswt-awt-gtk-3232.so
libswt-gnome-gtk-3232.so
libswt-mozilla-gtk-3232.so

overwriting the original ones .

3) the files:

org.eclipse.swt.gtk.linux.x86_3.2.0.v3232m.jar
org.eclipse.jface_3.2.0.I20060605-1400.jar

come from an eclipse installation actually, so if you don’t have eclipse,
download it and:

cd eclipse/plugins

and cp the org.eclipse.swt.gtk.linux.x86_64_3.4.1.v3449c.jar
into areca/lib org.eclipse.swt.gtk.linux.x86_3.2.0.v3232m.jar

and cp org.eclipse.jface_3.4.1.M20080827-2000.jar to areca/lib
org.eclipse.jface_3.2.0.I20060605-1400.jar

overwriting the original ones.

Now, the file libarecafs.so surprise, surprise is a 32 bit one, so I compiled the 64bit one.
With the 32bit one, you’ll get a couple of warnings:

09-01-22 20:44 – WARNING – com.myJava.file.metadata.posix.jni.JNIMetaDataAccessor cannot be used on this system. Got the following error : “java.lang.UnsatisfiedLinkError : /home/jordilin/areca/lib/libarecafs.so: /home/jordilin/areca/lib/libarecafs.so: wrong ELF class: ELFCLASS32 (Possible cause: architecture word width mismatch)”
09-01-22 20:44 – WARNING – [com.myJava.file.metadata.posix.jni.JNIMetaDataAccessor] not validated. The default metadata accessor will be used instead.

4) ./areca.sh
5) done

Note. I tested this using 6.2 pre-release, but using 6.1 should be the same.

Ubuntu Linux: How to Install Flash Player for firefox

Huy Tran — Sat, 27 Sep 2008 04:47:44 +0000

Install Flash Player For Ubuntu Linux

Type the following command to install flash player:

$ sudo apt-get install flashplugin-nonfree

Now flash player should be working. Visit youtube or any other site to view flash content.

add delete and switch user in ubuntu by command lines

Huy Tran — Sun, 20 Apr 2008 19:55:33 +0000

First, I want to add a user. So how to do it?

+ To add user:

sudo adduser

to add password for your user

sudo passwd

+ How can i switch from one user to another one? In this example, i want to switch from one user to another one.

and type in your password to login

after that, you will be at a ‘$’ prompt. type:

bash

to get to a normal prompt.

+ How can I delete a user?

sudo userdel

Terminal or shell command to shutdown or reboot Ubuntu Linux

Huy Tran — Sat, 09 Feb 2008 11:48:55 +0000

So how do you shutdown or reboot Ubuntu Linux from a terminal or a shell prompt? If GUI is working you can always click on a Quit button. If GUI is not working or if you are working remotely over ssh type the following command:

To shutdown / poweroff Ubuntu Linux

Type the command:

sudo halt

sudo shutdown -h now

sudo shutdown -r now

sudo init 6

To reboot Ubuntu Linux

Type the command:

sudo reboot

More information can be found about these two commands by typing following commands (man page):

man reboot
man shutdown