Posts Tagged ‘most linux distributions’

Converting jpeg / png pictures to mp4 format videos on Linux with avconv

Wednesday, June 12th, 2013

making mp4 videos from jpeg and png pictures gnu linux
Here in my job, there is one internet (TV) around which can only read video formats in Mp4. Henceforth I needed a way to convert a number of JPEG / PNG format Picture files to Mp4. In my situation I needed to make video out of pictures and script it as this was required to be later pushed via FTP protocol to the Internet TV. Ater doing some research I figured out this is possible to build video out of pictures by using together ImageMagick and avconv.

First thing is to send pictures in certain resolution. There is a tool from imagemagick package called mogrify (which can do that). To convert a number of different dimension pictures to lets say 1024×768, used:

noah:~# mogrify -resize 1024×768 *.png

In earlier Linux distributions to create a movie from pictures ffmpeg was used like so:

# ffmpeg -qscale 5 -r 20 -b 9600 -i SDC%04d.png movie.mp4

However in newer version of ffmpeg support for this is removed, and to make video from images, there is other tool avconv. On most Linux distributions avconv is part of libav-tools package.

To install on avconv Debian and Ubuntu;
noah:~# apt-get install –yes libav-tools

Once installed to create single mp4 video from JPEG or PNG pictures:

noah:~# avconv -i SDC106001.JPG SDC10595.JPG SDC13611.JPG SDC13612.JPG SDC13614.JPG  movie-from-pictures.mp4

I found there is also a nice GUI,software Open Movie Editor, which can create video out of number of pictuers stored in a directory. 
Open Movie Editor is available in most Linux distributions (unfortunately as of time of writting on Debian Wheeze there is no install candidate of openmovieeditor), there is however substitute package doing the same job called openshot);
On latest Debian stable to install Openshot:

noah:~# apt-get install –yes openshot

openshot running on Debian Wheezy Linux create video from pictures

Openshot has an option (Import Image Sequence) from File -> Import Image Sequence. Using this option you can select a directory with fles with common prefix name lets say IMG*.png and create Video based on the photos inside.

Linux create  video from images import image sequence Debian / Fedora and Ubuntu

On Ubuntu Linux or other distro where openmovieeditor is avialable install it with:

ubuntu:~# apt-get install –yes openmovieeditor

Openmovieeditor Linux create movies from images screenshot
To create a video out of pictures click on Media Browser tab. Choose the Folder with pictures from which video will be generated and drag them to the Video bar
(window).

To save produced video navigate to menus:

Project -> Render

and select format to save it as. One good codec to save output is Quicktime's. To convert later Quicktime MOV Video to MP4 video,
there is the  Pytube Media Converter script.

Well that's all enjoy your new videos from pictures 🙂

How to create user with only FTP access on Linux

Saturday, May 11th, 2013

Linux access only to ftp How to prohibit ssh access on GNU Linux

Creating user with access only through FTP is vital in daily routine system administration job. The reason why it is good to disable SSH access to users which don't need it is of course better security. Disabling access to ssh shell for users which don't need it prevents you for user to run malicious code usually exploits or some DDoS Fork bombs – like the infamous Linux shell Denial of Service string;

:(){ :|:&};:

Better not try above string on productive server 😉
So back to the topic here how to add Linux FTP only user;

1. Create a regular user with adduser or useradd (depending) on GNU / Linux distribution

adduser is available across most Linux distributions nowadays, however I remember in past there was some distros which had useradd instead. Anyways for most adduser should be ok. As of time of writting both 3 main stream Linux distributions Slackware, Debian and Fedora has adduser.

linux:~#  adduser new-user-for-ftp-only

Adding user `new-user-for-ftp-only' …
Adding new group `new-user-for-ftp-only' (1006) …
Adding new user `new-user-for-ftp-only' (1005) with group `new-user-for-ftp-only' …
Creating home directory `/home/new-user-for-ftp-only' …
Copying files from `/etc/skel' …
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for new-user-for-ftp-only
Enter the new value, or press ENTER for the default
    Full Name []: New Linux User Only for FTP access  
    Room Number []:
    Work Phone []:
    Home Phone []:
    Other []:
Is the information correct? [Y/n] Y

linux:~#

2. Change user shell /bin/bash to /bin/false

Again depending on Linux distribution by default /bin/bash /bin/sh or /bin/whatever shell will get added. To make just created user access to SSH disabled. Change shell to /bin/false – a tiny program which just returns a FALSE value and quits immediately.

There are two ways to do so;

a) Edit directly /etc/passwd with vim / joe

linux:~# vim /etc/passwd

Go to end of file and find the record for user, should be smth like:

 

new-user-for-ftp-only:x:1005:1006:New Linux User Only for FTP access,,,:/home/new-user-for-ftp-only:/bin/bash

Change to;

new-user-for-ftp-only:x:1005:1006:New Linux User Only for FTP access,,,:/home/new-user-for-ftp-only:/bin/false

b) Use chsh cmd

linux:~# chsh new-user-for-ftp-only

Changing the login shell for new-user-for-ftp-only
Enter the new value, or press ENTER for the default
    Login Shell [/bin/bash]: /bin/false

linux:~# grep -i new-user-for-ftp-only /etc/passwd

new-user-for-ftp-only:x:1005:1006:New Linux User Only for FTP access,,,:/home/new-user-for-ftp-only:/bin/false

3. Testing if ssh access to new user is disabled

linux:~# ssh new-user-for-ftp-only@localhost

new-user-for-ftp-only@localhost's password:
Linux noah 2.6.32-5-amd64 #1 SMP Mon Feb 25 00:26:11 UTC 2013 x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Connection to localhost closed.

How to check what process is listening on network port with: lsof & fuser commands in Linux / BSD

Saturday, March 16th, 2013

It is a common thing for me as a Linux and FreeBSD sysadmin to know what process assignes to which port number? I'm sure many novice system administrators will end up sooner or later with same question. Knowing what kind of processes has listening to TCP and UDP protocol / ports is a must to have a proper configured Linux / BSD system. In Linux there are two commands ( lsof and fuser) with which you can get various extra PID information on running processes (i.e. get information which cannot otherwise be obtained via the usual ps and netstat  To use them on most Linux distributions, you will have to have them installed.

1. Install fuser / lsof on Linux / BSD

a) On RPM based Linux distros – Fedora, CentOS, RHEL, SuSE /sbin/fuser is usually part of base install psmisc rpm package, however /usr/sbin/lsof is not among standard installed rpms, so you have to manually install via yum:

[root@centos ~]# yum install -y lsof
….

b) On Deb based Linuxes (Debian, Ubuntu, Mint, ArchLinux etc.). both lsof and fuser has to be installed via a separate packages non-part of Debian base install packs.

server:~# apt-get --yes install lsof fuser
....

On Debian full path location of both is in /bin/fuser and /usr/bin/lsof.

Two tools are precious swiss army knife outfit to use, whether you doubt someone cracked into a server or in doubt you might have "hidden" cracker processes on server.

c) Install fuser on Free/Net/Open/ BSD

bsd# cd /usr/ports/sysutils/fuser
bsd# make install clean
....
bsd# cd /usr/ports/sysutils/lsof
bsd# make install clean
....

2. Using fuser and lsof to look up process PIDs assigned to port numbers

lsof name is derived from List Open Files, as we know in UNIX, GNU / Linux,  *BSD everything on the system is a file, thus to get all kind of information concerning all active files (i.e. ports, PIDs, procotols and process names;

server:~# lsof +M -i4 | less

COMMAND     PID     USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
portmap    1317   daemon    4u  IPv4     3930      0t0  UDP *:sunrpc[portmapper]
portmap    1317   daemon    5u  IPv4     3939      0t0  TCP *:sunrpc[portmapper] (LISTEN)
rpc.statd  1329    statd    4u  IPv4     3974      0t0  UDP *:657
rpc.statd  1329    statd    6u  IPv4     3983      0t0  UDP *:28530[status]
rpc.statd  1329    statd    7u  IPv4     3986      0t0  TCP *:58515[status] (LISTEN)
apache2    1625 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    1625 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
sshd       1918     root    3u  IPv4     4945      0t0  TCP *:ssh (LISTEN)
miniserv.  2155     root    5u  IPv4     5299      0t0  TCP *:20000 (LISTEN)
miniserv.  2155     root    6u  IPv4     5300      0t0  UDP *:20000
miniserv.  2161     root    6u  IPv4     5367      0t0  TCP *:webmin (LISTEN)
miniserv.  2161     root    7u  IPv4     5368      0t0  UDP *:10000
ntpd       2172      ntp   16u  IPv4     5395      0t0  UDP *:ntp
ntpd       2172      ntp   18u  IPv4     5402      0t0  UDP localhost:ntp
ntpd       2172      ntp   19u  IPv4     5403      0t0  UDP iqtest.soccerfame.com:ntp
ntpd       2172      ntp   20u  IPv4    16028      0t0  UDP secure.broomlake.com:ntp
apache2    4505 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4505 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    4539 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4539 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    4780 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4780 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    4900 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4900 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    4907 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4907 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    4915 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    4915 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5067 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5067 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5133 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5133 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5134 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5134 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5148 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5148 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5152 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5152 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5259 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5259 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5265 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5265 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5266 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5266 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5346 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5346 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5356 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5356 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5467 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5467 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5523 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5523 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5568 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5568 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5715 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5715 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5716 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5716 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5758 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5758 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    5789 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    5789 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2    6106 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2    6106 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   16608 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   16608 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   16904 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   16904 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   17124 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   17124 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   17280 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   17280 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   20855 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   20855 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   20920 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   20920 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   21023 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   21023 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   22182 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   22182 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23307 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23307 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23366 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23366 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23408 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23408 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23419 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23419 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23428 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23428 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23452 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23452 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23561 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23561 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23579 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23579 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   23851 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   23851 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   24103 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   24103 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   24659 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   24659 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
sshd      25073     root    3u  IPv4 29855891      0t0  TCP iqtest.soccerfame.com:ssh->pc-freak.net:50176 (ESTABLISHED)
sshd      25084     hipo    3u  IPv4 29855891      0t0  TCP iqtest.soccerfame.com:ssh->pc-freak.net:50176 (ESTABLISHED)
apache2   25089 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   25089 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   26737 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   26737 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   27243 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   27243 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   27282 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   27282 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   27633 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   27633 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   28205 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   28205 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   29244 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   29244 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   29372 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   29372 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   29411 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   29411 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   29462 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   29462 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   29548 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   29548 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   30161 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   30161 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   31876 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   31876 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   31958 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   31958 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32052 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32052 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32061 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32061 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32143 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32143 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32149 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32149 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32440 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32440 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32635 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32635 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   32790 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   32790 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   40211 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   40211 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   40309 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   40309 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   40432 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   40432 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   40476 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   40476 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46319     root    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46319     root    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46438 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46438 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46439 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46439 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46440 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46440 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46441 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46441 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46442 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46442 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46443 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46443 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46509     root    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46509     root    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46510     root    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46510     root    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   46515     root    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   46515     root    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   51287 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   51287 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   51485 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   51485 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   51804 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   51804 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
named     54418     bind   20u  IPv4 31298857      0t0  TCP localhost:domain (LISTEN)
named     54418     bind   21u  IPv4 31298859      0t0  TCP iqtest.soccerfame.com:domain (LISTEN)
named     54418     bind   22u  IPv4 31298861      0t0  TCP secure.broomlake.com:domain (LISTEN)
named     54418     bind   23u  IPv4 31298865      0t0  TCP localhost:953 (LISTEN)
named     54418     bind  512u  IPv4 31298856      0t0  UDP localhost:domain
named     54418     bind  513u  IPv4 31298858      0t0  UDP iqtest.soccerfame.com:domain
named     54418     bind  514u  IPv4 31298860      0t0  UDP secure.broomlake.com:domain
named     54418     bind  515u  IPv4 31298864      0t0  UDP *:domain
proftpd   62010  proftpd    1u  IPv4 31306260      0t0  TCP *:ftp (LISTEN)
mysqld    62420    mysql   11u  IPv4 31306903      0t0  TCP *:mysql (LISTEN)
apache2   62582 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   62582 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   62845 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   62845 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)
apache2   64748 www-data    3u  IPv4     5456      0t0  TCP *:www (LISTEN)
apache2   64748 www-data    4u  IPv4     5458      0t0  TCP *:https (LISTEN)

Above lsof command lists all active listening processes port number on UDP and TCP/IP 4 proto with the assigned process PID number (in second column). This is very useful if you find out to have listening service on port number and you cannot figure out what process name exactly is listening.

A classic example, where this is very helpful is if you have a listening process on SMTP port 25 and you cannot identify what kind of mail server is taking up the port? This has happened me many times on Debian Linux based hosts, which by default had priorly installed sendmail and I later removed sendmail to install Postfix or Exim SMTP.
To find out what is assigning port 25, you had to grep the protocol name from all binded host processes, like so:

 

server:~# lsof +M -i4 | grep -i smtp

exim4     17550     root    3u  IPv4 31577966      0t0  TCP localhost:smtp (LISTEN)

Whether you want to get information on Process ID, binding other random port lets say port 10000, following same logic you can grep it:

server:~# lsof +M -i4 |grep -i 10000
miniserv.  2161     root    7u  IPv4     5368      0t0  UDP *:10000

To get rid of a process for which you're unsure what kind of (/etc/init.d/service-name) init script is starting it, you can then use kill cmd to stop it;

server:~# kill -9 2161

Second approach to find out what kind of process is listening on a random port or socket, lets say port num 58515 is by using fuser.

 

 

server:~# netstat -ltn4
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State     
tcp        0      0 0.0.0.0:3306            0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:10000           0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:58515           0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:21              0.0.0.0:*               LISTEN    
tcp        0      0 77.92.85.71:53          0.0.0.0:*               LISTEN    
tcp        0      0 109.123.106.44:53       0.0.0.0:*               LISTEN    
tcp        0      0 127.0.0.1:53            0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN    
tcp        0      0 127.0.0.1:953           0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:443             0.0.0.0:*               LISTEN    
tcp        0      0 0.0.0.0:20000           0.0.0.0:*               LISTEN    

Below netstat cmmand, lists all active listening processes on respective IP address and port for protocol TCPIP v.4.

Hence on to get more information on what process is listening on port 58515?

server:~#  fuser -v 58515/tcp

                     USER        PID ACCESS COMMAND
58515/tcp:           statd      1329 F…. rpc.statd

Once you know what is listening, whether you want to kill it this is also possible directly through fuser;

 

server:~# fuser -vk 58515/tcp

As a close-up, I will say fuser and lsof are two must have software tools on any productive server. It is among the critical applications admin has to install during initial server set-up. fuser and lsof helps me often in my sysadmin work, it was more than once I've used them to identify script-kiddies exploit scanners running as a standard process names, as well secretly listening on weird port number  cracker back-doors.

Hopefully this little article, helps someone learn something new. Plenty is written and will be written and if one takes the time to research he can learn much, much more. I'm sure my tiny article is nothing new under the sun for old-school admins, I still hope it will be of use to novice. I'm looking forward to hear if I'm missing some neat use or some interesting case, when lsof or fuser "saved your ass" 🙂
 

Download and Play Apogee’s Raptor (Call of the Shadows) DOS arcade game on GNU / Linux and BSD* with dosbox / Few words on Apogee and Shareware

Thursday, January 19th, 2012

Since its early days dosbox has elolved a lot. For all those who haven't heard of dosbox, it is x86 Free Software Linux / FreeBSD DOS emulator

DosBox supports, almost all the game classics we used top lay in oldschool times when DOS (Disk Operating System ) version was running on top of most personal computer.

The most spread versions of DOS people used to use on their PCs were Novell (DR-DOS) more rarely used, and MS-DOS (The Microsoft DOS ver.).

I'm sometimes being sentimental about the past so I remembered for Raptor Call of the Shadows !

Having a bit of experience with DOSBox to run few DOS games I've decided to give a try with dosbox.

First I have to dig for this shareware, since this game is part of the sharewares, nowdays a binary version of it is freely distributed on the net.
Finding the game however took me about 10 minutes, as most of the download links for Raptor, were either dead or required some kind of registration. After a bit of look I found it on an old torrent with few seeders and succeded downloading.

For the convenience of people who would like to download run the Raptor arcade classic game check here

Nicely Raptor works out of the box directly launched with dosbox emulator.
Dosbox has packages for most Linux distributions.
I personally used it on my Debian Linux so installed via apt:

debian:~# apt-get install dosbox
...

The game works without any dosbox hacks, just download, unarchive and launch with dosbox:

hipo@debian:~$ wget http://www.pc-freak.net/files/Raptor_Call_of_The_Shadows_Apogee_arcade.tar.gz
...
hipo@debian:~$ tar -zxvf Raptor_Call_of_The_Shadows_Apogee_arcade.tar.gz
...
hipo@debian:~$ cd Raptor/
hipo@debian:/home/hipo/Raptor$ dosbox rap.exe

Apogee Raptor Screenshot Dosbox Debian linux

Raptor Call of the Shadows main screen linux debian

Dosbox raptor level

People like me 😉 who lived in that glorious times when DOS was a standard for a desktop operating system pretty much like MS Windows is today, certainly remember the awesome games produced by Apogee Software a company later known as 3D Realms

Apogee until this very day remain one of the greatest game creation companies in history of games. 3D Realms played a crucial role in development of PC game industry as well as has a great santimental value to probably million of old school arcade game addicts.

They can be ben undoubtedly can be praised for having created some of the most awesome arcade games for all times.

Some of the early hit games they created you probably know, few of the titles are:

  • Duke Nukem I, II
  • Arctic Adventure
  • Monster Bash
  • Stargunner
  • Commander Keen series
  • Wolfenstein 3D
  • Blake Stone
  • Terminal Velocity (Terminal Reality)
  • Shadow Warrior
  • Death Rally
  • Blood

Apogee was also notable for being a company to had established the so spread mostly during the late 80s up to the early years of the second millenium.

ShareWare model of distribution is an interesting phenomenon, that co-relates more or less with the ideas of Free Software.
The idea of ShareWare games was games are distributed for Free and the end customer (gamer) is asked to pay for a game only if he likes it.

Some of the shareware published games was available for free download and play, however the game was only bundled with only a number of game levels to unlock the rest of the game levels you had to play some money.

The shareware games produced were then freely published and shared via dial up access BBS nodes (A text based Bulletin Board System similar to nowdays Forums).
BBS has historically been the major way of sharing knowledge and exchanging ideas and opinions preceding the massive rise of the WEB.
Today most computer users would probably even haven't heard about BBS, if you like to have a general idea on how BBSes seemed to look dahmer.vistech.net .

ShareWare started to loose speed with the decline of BBS and the emergence of Free Software.

Some of the conceptual ideas of ShareWare found its way in "Open Source & Free Software", and commercial companies like RedHat and SuSE.

If you have tried some other Apogee games with Dosbox on Linux and FreeBSD and you can positively confirm they work it will be great. In theory all of the DOS games of apogee should work fine with dosbox. Any feedback or game recommendations of your favourite games of the DOS years are mostly welcome in comments. I'm curious to hear what was your favourite DOS game. Maybe when I have time I'll prepare a list of my favourite games put them here 😉

How to mount ISO image files in Graphical Environment (GUI) on Ubuntu and Debian GNU/Linux

Saturday, January 14th, 2012

Mounting ISO files in Linux is easy with mount cmd, however remembering the exact command one has to issue is a hard task because mounting ISO files is not a common task.

Mounting ISO files directly by clicking on the ISO file is very nice, especially for lazy people uninitiated with the command line 😉

Besides that I'm sure many Windows users are curious if there is an equivallent program to DaemonTools for Linux / BSD*?

The answer to this question is YES!
There are two major programs which can be used as a DaemonTools substitute on Linux:

These are FuriousISOMount and AcetoneISO
AcetoneISO is more known and I've used it some long time ago and if I'm correct it used to be one of the first ISO Mount GUI programs for Linux. There is a project called GMount-ISO / (GMountISO) which of the time of writting this article seems to be dead (at least I couldn't find the source code).

Luckily FuriousISOMount and AcetoneISO are pretty easy to install and either one of the two is nowdays existing in most Linux distributions.
Probably the programs can also be easily run on BSD platform also quite easily using bsd linux emulation.
If someone has tried something to mount GUIs in Free/Net/OpenBSD, I'll be interesting to hear how?

1. Mount ISO files GUI in GNOME with Furius ISO Mount

FuriousISOMount is a simple Gtk+ interface to mount -t iso9660 -o loop command.

To start using the program on Debian / Ubuntu install with apt;

debian:~# apt-get install furiusisomount
The following extra packages will be installed:
fuseiso fuseiso9660 libumlib0
The following NEW packages will be installed:
furiusisomount fuseiso fuseiso9660 libumlib0

To access the program in GNOME after install use;

Applications -> Accessories -> Furious ISO Mount

Screenshot ISO Mount Tool Debian GNU/Linux Screenshot
 

When mounting it is important to choose Loop option to mount the iso instead of Fuse

After the program is installed to associate the (.iso) ISO files, to permanently be opened with furiusisomount roll over the .iso file and choose Open With -> Other Application -> (Use a custom command) -> furiusisomount

GNOME Open with menu Debian GNU / Linux

2. Mount ISO Files in KDE Graphical Environment with AcetoneISO

AcetoneISO is build on top of KDE's QT library and isway more feature rich than furiousisomount.
Installing AcetoneISO Ubuntu and Debian is done with:

debian:~# apt-get install acetoneiso
The following NEW packages will be installed:
acetoneiso gnupg-agent gnupg2 libksba8 pinentry-gtk2 pinentry-qt4
0 upgraded, 6 newly installed, 0 to remove and 35 not upgraded.
Need to get 3,963 kB of archives.
After this operation, 8,974 kB of additional disk space will be used.
...

Screenshot Furius ISO Mount Tool Debian GNU/Linux ScreenShot

AcetoneISO supports:
 

  • conversion between different ISO formats
  • burn images to disc
  • split ISO image volumes
  • encrypt images
  • extract password protected files

Complete list of the rich functionality AcetoneISO offers is to be found on http://www.acetoneteam.org/viewpage.php?page_id=6
To start the program via the GNOME menus use;

Applications -> Accessories -> Sound & Video -> AcetoneISO

I personally don't like AcetoneISO as I'm not a KDE user and I see the functionality this program offers as to rich and mostly unnecessery for the simple purpose of mounting an ISO.

3. Mount ISO image files using the mount command

If you're a console guy and still prefer mounting ISO with the mount command instead of using fancy gui stuff use:

# mount -t iso9660 -o loop /home/binary/someiso.iso /home/username/Iso_Directory_Name

 

Geki2 and Geki3 a Xenon 2 Megablast like games for GNU / Linux and FreeBSD

Thursday, December 22nd, 2011

Do you remember the old arcade spaceship shooter Xenon 2 Megablast? I do 😉 For all those who are too young to remember, here are two screenshots:

Xenon2 Main game Screen PC DOS ver

Xenon 2 megablast PC DOS level screenshot

Even though Xenon 2 Megablast original can now be played using dosbox DOS emulator. Its interesting to mention I've found two Linux games that more or less can be qualitified to resemble Xenon 2.
The games are Native Free Software games and existing in package repositories of most Linux distributions and *BSD port trees.

Geki 2 and Geki 3 are of a less quality to Xenon but still, the game experience is nice and is among the Arcade shooter games to bring you fun in the boring days if you're on GNU / Linux or FreeBSD Free OS platforms.

Installing Geki2 and Geki3 on Debian and Ubuntu Linux is standard with apt:

debian:~# apt-get install geki2 geki3
...

On Debian GNU / Linux , after installed the games would not create GNOME Applications -> Games -> game startup shortcuts, however the game startups will get added in GNOME Applications Menu under:

Applications -> Debian -> Games -> Action -> Geki 2
and
Applications -> Debian -> Games -> Action -> Geki 3

The games can be launched also manually with commands:

geki2

Geki 2 Linux Xenon 2 like game Main Menu

or

geki3
Geki3 gameplay screenshot Debian Linux

Geki 2 is a way closer to Xenon 2 as it has similar look and feel and the same vertical direction the spaceship is navigated.
In Geki 3 still the shoot 'em' up spaceship like arcade is present, however instead of penguin you have to fly a flying penguin, as well as the spaceship move direction is horizontal.

 Both the games have the same sound and music effects. The game music and effects are not of top quality but are not bad. In general  the games surely gives some of the arcade atmosphere.

Geki 2 GNU Linux Xenon 2 like vertical shooter arcade
Geki 2 Xenon 2 Megablast like on Debian Linux

In the tradition of the arcade games at the end of each level in both games you face the Level Boss Enemy, you should destroy.

Geki3 Level boss Debian Linux Screenshot
As you can see in below's screenshot the overall graphics of GEKI 3 is poorer while compared to GEKI 2

still GEKI 2 gampley is fun and addictive and I would say not less enjoyable than GEKI 2.
 At times I even think that Geki 3 is more fun because it is more dynamic.

 Maybe other reason, why I enjoyed more Geki 3 is also the fact that Geki 2 is a way harder to play. Dying only 3 times in the game you get  GAME OVER  and the next game you're started from the beginning of the same level you died in …

Geki2 Linux different shooting Screenshot

 Something really annoying that affects both the games; there is no option to play them in Fullscreen mode! ARGH!

Game controls for Geki2 and Geki3 are identical as follows:

Up - Arrow up key
Down - Down arrow key
Right - Right arrow key
left - Left arrow key
Shoot - z or Space
Pause - s

Geki2 and Geki3 are fun and can kill some time, but definitely aren't that (professional) as other spaceship shoot'em'up arcades for Linux and BSD. Games like Starfighter , Critical Mass or  powermanga .
 Lest that they are two worthy to install and play on your Free Software OS.

How to crack password protected rar and 7z files on GNU / Linux

Friday, October 7th, 2011

break / crack password protected rar, zip archives on Linux and FreeBSD rarcrcack

RarCrack is able to crack rar and 7z archive files protected by password on Linux.
The program is currently at release version 0.2, so its far from perfection, but at least it can break rars.

RarCrack is currently installable on most Linux distributions only from source, to install on a random Linux distro, download and make && make install . RarCrack’s official site is here, I’ve mirrored the current version of RarCrack for download here . To install rarcrack from source using the mirrored version:

linux:~# wget http://www.pc-freak.net/files/rarcrack-0.2.tar.bz2
...
linux:~# tar -jxvvf rarcrack-0.2.tar.bz2
linux:~# cd rarcrack-0.2
linux:~/rarcrack-0.2# make
...
linux:~/rarcrack-0.2# make install
...

On FreeBSD, rarcrack is available and installable via the ports tree, to install on FreeBSD:

freebsd# cd /usr/ports/security/rarcrack
freebsd# make && make install
...

To use RarCrack to crack rar, zip or 7z archive file:

freebsd% rarcrack rar_file_protected_with_password.rar --type rar

The argument –type rar is optional, in most archives RarCrack should detect the archive automatically. The –type option could also take the arguments of rar and 7z .

I’ve created a sample rar file protected with password linux_then_and_now.png.rar . The archive linux_then_and_now.png contains a graphic file illustrating the linux growth in use in computers, mobiles and servers. linux_then_and_now.png.rar is protected with the sample password parola

RarCrack also supports threads (a simultaneous instance spawned copies of the program). Using threads speeds up the process of cracking and thus using the –threads is generally a good idea. Hence a good way to use rarcrack with the –threads option is:

freebsd% rarcrack linux_then_and_now.png.rar --threads 8 --type rar
RarCrack! 0.2 by David Zoltan Kedves (kedazo@gmail.com)
INFO: the specified archive type: rar
INFO: cracking linux_then_and_now.png.rar, status file: linux_then_and_now.png.rar.xml
Probing: '0i' [24 pwds/sec]
Probing: '1v' [25 pwds/sec]

RarCrack‘s source archive also comes with three sample archive files (rar, 7z and zip) protected with passwords for the sake of testing the tool.
One downside of RarCrack is its extremely slow in breaking the passwords on my Lenovo notebook – dual core 1.8ghz with 2g ram it was able to brute force only 20-25 passwords per second.
This means cracking a normal password of 6 symbols will take at least 5 hours.
RarCrack is also said to support cracking zip passwords, but my tests to crack password protected zip file did not bring good results and even one of the tests ended with a segmentation fault.

To test how rarcrack performs with password protected zip files and hence compare if it is superior or inferior to fcrackzip, I used the fcrackzip’s sample pass protected zip noradi.zip

hipo@noah:~$ rarcrack --threads 8 noradi.zip --type zip
2 by David Zoltan Kedves (kedazo@gmail.com)
INFO: the specified archive type: zip
INFO: cracking noradi.zip, status file: noradi.zip.xml
Probing: 'hP' [386 pwds/sec]
Probing: 'At' [385 pwds/sec]
Probing: 'ST' [380 pwds/sec]

As you can see in above’s command output, the zip password cracking rate of approximately 380 passwords per second is a bit quicker, but still slower than fcrackzip.

RarCrack seg faults if cracking a pass protected zip is passed on without specifying the –type zip command arguments:

linux:~$ rarcrack --threads 8 noradi.zip
RarCrack! 0.2 by David Zoltan Kedves (kedazo@gmail.com)
Segmentation fault

While talking about cracking protected rar and zip archives with password, its worthy to mention creating a password protected archive with Gnome Desktop on Linux and FreeBSD is very easy.

To create the password protected archive in Gnome graphic environment:

a. Point the cursor to the file you want to archive with password

Gnome pointing file properties drop down menu

b. Press on Other Options and fill in the password in the pwd dialog

Linux protect rar with password on Gnome Desktop

I think as of time of writting, no GUI frontend interface for neither RarCrack or FcrackZip is available. Lets hope some good guy from the community will take the time to write extension for Gnome to allow us to crack rar and zip from a nice GUI interface.

How to find out which processes are causing a hard disk I/O overhead in GNU/Linux

Wednesday, September 28th, 2011

iotop monitor hard disk io bottlenecks linux
To find out which programs are causing the most read/write overhead on a Linux server one can use iotop

Here is the description of iotop – simple top-like I/O monitor, taken from its manpage.

iotop does precisely the same as the classic linux top but for hard disk IN/OUT operations.

To check the overhead caused by some daemon on the system or some random processes launching iotop without any arguments is enough;

debian:~# iotop

The main overview of iostat statistics, are the:

Total DISK READ: xx.xx MB/s | Total DISK WRITE: xx.xx K/s
If launching iotop, shows a huge numbers and the server is facing performance drop downs, its a symptom for hdd i/o overheads.
iotop is available for Debian and Ubuntu as a standard package part of the distros repositories. On RHEL based Linuxes unfortunately, its not available as RPM.

While talking about keeping an eye on hard disk utilization and disk i/o’s as bottleneck and a possible pitfall to cause a server performance down, it’s worthy to mention about another really great tool, which I use on every single server I administrate. For all those unfamiliar I’m talking about dstat

dstat is a – versatile tool for generating system resource statistics as the description on top of the manual states. dstat is great for people who want to have iostat, vmstat and ifstat in one single program.
dstat is nowdays available on most Linux distributions ready to be installed from the respective distro package manager. I’ve used it and I can confirm tt is installable via a deb/rpm package on Fedora, CentOS, Debian and Ubuntu linuces.

Here is how the tool in action looks like:

dstat Linux hdd load stats screenshot

The most interesting things from all the dstat cmd output are read, writ and recv, send , they give a good general overview on hard drive performance and if tracked can reveal if the hdd disk/writes are a bottleneck to create server performance issues.
Another handy tool in tracking hdd i/o problems is iostat its a tool however more suitable for the hard core admins as the tool statistics output is not easily readable.

In case if you need to periodically grasp data about disks read/write operations you will definitely want to look at collectl i/o benchmarking tool .Unfortunately collect is not included as a packaget for most linux distributions except in Fedora. Besides its capabilities to report on servers disk usage, collect is also capable to show brief stats on cpu, network.

Collectl looks really promosing and even seems to be in active development the latest tool release is from May 2011. It even supports NVidia’s GPU monitoring 😉 In short what collectl does is very similar to sysstat which by the way also has some possibilities to track disk reads in time.  collectl’s website praises the tool, much and says that in most machines the extra load the tool would add to a system to generate reports on cpu, disk and disk io is < 0.1%.  I couldn’t find any data online on how much sysstat (sar) extra loads a system. It will be interesting if some of someone concluded some testing and can tell which of the two puts less load on a system.