Posts Tagged ‘basis’

Richard Stallman explaining Why IPads and Cell Phones are bad for freedom

Wednesday, July 11th, 2012

It is a public secret that Mobile Phones which does us very good and generally makes our daily lifes way easier are also a big enemy to our natural ihnibited freedom. Life has become such that it is almost inevitable to do any business or do a daily simple jobs without using Mobile Phone. There is almost none practically today that has wilfully rejected to use the mobile phone on any basis, almost anyone except some strangers like Richard Stallman and probably few others security freaks.

I've been shocked to find out the Father of Free Software (Richard Mathew Stallman), well known in the hacker dome as RMS does not own and didn't use any mobiles. The concerns he pointed are very much logical and rightful. Owning a mobile is a great security hole in personal privacy (mobile phones can be easily sniffed by Mobile Operators) as well as anyone wearing a mobile can be tracked up to 5 to 2 meters to the exact location where he is based on the mobile phone cells to which the mobile is connected.

Many people are not aware actually of the severeness of the issue of constant tracking of people everywhere through this call "goodies". Many mobile operators are already running a software which is building place behaviour patterns of every user of their mobile network. In other words, as we're used to bring and use the mobile everywhere in automated program is creating a map for each number assigned in some of the mobile operators. The gathered data about our location going habits can then be easily used as a indicator for predicting our future behaviour, bying habits (how many times we go to super-market), how many times we go to cinema, what kind of interests we hold etc. etc.
This combined with Google, account monitoring could possibly create a system similar to the old movies Big Brother, where all people goods and even attitudes or desires is monitored, influenced and controlled ….

The severeness of the future implications of this constant "personal surveillance and tracking device" as Stallman use to call it is very dangerous for our freedoms.

I tried to live without a mobile phone, just like Stallman for about months, and to tell you the truth the world around seems completely different when you decide not to use 'em. The time I lived wihtout a mobile, clearly show me we have come to the point we cannot any more live without GSM. We fall the trap of dependanding the little "talk box" communication for absolutely everything, obviously sacrificing privacy and freedom for convenience.
Mobiles are just one side of the coin, as the non-free software which is ruling the software market and the use of computers puts another treat and takes away many foundamential freedoms we used to have in the less technological world.

Apple as a vendor of software and hardware also denies and breaks our freedom very badly, as the company tracks everyone who owns anything created by apple connected to the internet. Besides that non-free software producers, could change the user software with a press of a button giving them the opportunity to decide what is good and bad for us, leaving us at a state of a helpless dependable users.

The topic of technological little-by-little enslavement, we're going through nowdays and the denying freedoms, we experience while being convinced by companies that we became more free by each next mambo-jambo gadget or by owning the latest smart-phone is very huge and complex but unfortunately underseen in society. I don't understand why, is it due to the low technical skills of mass users is it due to a "not-care what will happen in future" attitude, but obviously people openly discussing or protesting the technologization taking away our freedom is almost zero ….

Here is the video I found in youtube in which Stallman is asked few, questions on Ipads (IBADS) and Mobile Phone use. I believe his short explanation synthesizes the problem quite well ;;;;

I just wonder after you check the video, Would you still accept an Ipad as a birthday gift ? 🙂
Do you still think cell-phones are "good" freedom safe and reliable ?

How road signs evolved / short history of roadsigns

Friday, June 29th, 2012

how the road signs evolved brief history of road signs Ancient Roman Road of Tall Aqibrin

As a person interested in history and antrophology. Just recently on my last trip to Romania as I travelled a very interesting question poped up in my mind – How it happened that RoadSigns we use on every street highway and practically everywhere on the road came to be. Interestingly now with the standartization of road signs often the most popular road signs are used as a basis for development on other popular prohibit or allowance signs, we read on airports public institutions, pubs and mostly everywhere.

So in short I did a short research on Road Sign History, just to find out once again that the ancients, were wiser than we think. The first road signs probably came to existence with the existence of humanity, however officially, there was no standartization of using signs to point on road locations travellers before it was introudced in the Roman Empire. In Rome a pillars on the roads were placed to point to major road arteries leading to Rome and various important empire city centers.

During the middle ages, milestones pillars were no longer used, but for practical reasons wooden markers placed across european cities instructed tradesman and travellers to major city important centers and were used to show a general road direction leading to nearby city.
The wooden signs practice had been in use until the first modern roadsigns erected  on a wide scale designed for riders of 'high' and ordinary bicycles in the late 1870 and 1880s. The modern road signs as we know it today however emerged as a result of the  first International Road Congress meeting that occured in Rome in 1908.
On the meeting a four standard pictures were selected to note the basic for road signs further development. The need for the meeting was the large increase of roads across european artery cities. The road signs developed on the meeting were bump, curve, intersection and railroad crossings. The invention and adoption of cars and the boom of the car producing industry quickened the need for international road sign standard. The intensive work on international road signs that took place between 1926 and 1949 eventually led to the development of the European road sign system as we know it. The signs were quicky spread to America and in 1960, the road signs become universal in America and almost everywhere all around the developed and developing world.

As of today 2012 it can be said road signs exist all around the civilized world.Though most of road signs are identical across all countries around the world today still some road symbols varies from country to country. I remember seeing some very unique road signs during my travelling through Serbia, 2 years ago.
 

Color Psychology – Color Mind Programming or how big companies boost their sales and make up your mind

Thursday, June 21st, 2012

Colors Programming Color mind Programming, how big companies boost their sales and make up your mind

As I've pointed earlier there is plenty of "secretly" kept and less known by public research on how colors influence us daily. The biggest companies are heavily taking advantage of what is found and known for colors impact on our minds (psyche). Actually there is a whole branch in psychology which deals with impact of colors perception on us.Besides companies, many modern governments are well aware of the many facts on how citizens percept colors and use this in color 'installment' in government offices and government institutions.

There is no universal knowledge on how colors completely affect us as every human on earth is very unique and saying this or that color has this or that impact on indivirual or group is not 100% accurate. However there are general traits nowdays formed especially with globalization and unification of TV ads and big companies corporate image, a unification started on how different nationality people perceive colors.

Nowdays in developed countries there are more and more people who perceive certain colors in similar fashion. Therefore every serious top marketer should carefully study colors and their relation with ancient time people believes and understanding on what each of the 'rainbow' colors symbolize. Most likely because there is no completely unified understanding of colors between various individuals may companies like Google and Microsoft started using all the rainbow colors in their basic company logos and branding for more on this topic please check my previous blog post Color trick Microsoft and Google use to keep their users loyal

Another large industry area, where color programming is very heavy is Computer and Video Games. You certainly still remember large portions of the games like Sega’s Sonic the HendgeHog or Mario Super Bros. or even the old arcade machines with games like Punisher or Cadillacs and Dinosaurs, Street Fighter etc.
All this old arcade games have a big portion of Color programming embedded in and this is one of the main reasons we remember them for a long time and playing them evoked such a strong feelings in youth.

This trend of using colors to make up our minds is being observed for many other physical goods as well as is starting to get more and more heavy adoption by websites branding on the internet.
Actually those with most succesful businesses on the internet have already integrated some kind of color programming scheme. An example for this would be the Internet top domain names seller GoDaddy. The have adopted a green scheme as a primary color combined with some other ones to create in the customer a feeling of ecology, naturality, peace and solitude.

The study of color programming is one major field to be known by anyone truly willing to understand why certain big store chainslike Carrefour, Lidl, Billa, MediaMarkt – in western europe or TechnoMarket, TechnoPolis (MediaMarkt copied tech equipment by shops here in Bulgaria) are decorated inside the way they are. I personally didn't like the concept of color programming since from Spiritual point of view it is a big evil. Trying to manipulate people perception to do something you would like to in general is very evil from spiritual point of view. A mixture of rainbow colors in a natural environment for example flowers in the wood or wild mountain place is one thing, but making it artificial and placing it in certain pre-desired order is totally another. Besides that the colors in the natural environment are natural and therefore the impact on us even if colorful is very much better than if it is done with a certain intention like in the big supermarkets stores, fast just food companies – McDonalds, Burger King etc.

The research on color mind influcence – Color mind programming is a controversial science. Nowdays many big businesses however use this as a granted science, even whole business sects with some mambo-jambo believes universities, children garden and schools in modern countries have employed the use of some type of color programming aiming to influence their pupils, students (organizational members – you call it).
Color mind programming and heavy use on advertisements on the TV, the Internet, Stores and mostly everywhere are however starting to took their tolls. The high increase in mental problems and dumbness in developed and some undeveloped countries as well as the increased number of people who go insane because of too much color programming is reality. The believe that mental programming is one of the ultimate tools to influence somebody and push him to do things you want like consome more of a product or generally consume (buy) more goods creates another severe issue it makes people to constantly over-consume (eat more than the body needs) and this increases the number of over-consumption evoked diseases …

But color programming doesn't stop with just the material (physical) surrounding world it is a concept highly employed in online based marketing. Online business is seen on so many top used websites, social networks like take for instance (facebook). It is so spread that even the software primary vendors like Microsoft, search engines Google Inc. have already heavily employed the color programming as a basis of their products.

There is another reason why most vendors nowdays issue their physical or 'virtual' products so colorful using all the colors of the rainbow. The reason is the fact that as a kids through animation, cartoons, toys and surrounding environment we have been exposed already even from our very youth age to a kind of color programming through kids toys we've been given by our parents). Hence the young years color programming became a basis for a future time color programming. The colorfulness of our kids years are already sub-consciously stored in our minds, so almost naturally there is a feeling of joy to pop-up once we see something childishly colorful.
 

Facebook use in organizations harmful for company businesses – How to block facebook access to company or organization network on Linux routers

Wednesday, May 2nd, 2012

Facebook harms company and organization employee efficiency picture, Falling company efficiency diagram due to facebook employee use

I don't know if someone has thought about this topic but in my view Facebook use in organizations has a negative influence on companies overall efficiency!
Think for a while, facebook's website is one of the largest Internet based "people stealing time machine" so to say. I mean most people use facebook for pretty much useless stuff on daily basis (doesn't they ??). The whole original idea of facebook was to be a lay off site for college people with a lot of time to spend on nothing.
Yes it is true some companies use facebook succesfully for their advertising purposes and sperading the awareness of a company brand or product name but it is also true that many companies administration jobs like secretaries, accountants even probably CEOs loose a great time in facebook useless games and picture viewing etcetera.

Even government administration job positioned people who have access to the internet access facebook often from their work place. Not to mention, the mobility of people nowdays doesn't even require facebook to be accessed from a desktop PC. Many people employeed within companies, who does not have to work in front of a computer screen has already modern mobile "smart phones" as the business people incorrectly call this mini computer devices which allows them to browse the NET including facebook.

Sadly Microsoft (.NET) programmers and many of the programmers on various system platforms developers, software beta testers and sys admins are starting to adopt this "facebook loose your time for nothing culture". Many of my friends actively use the Facebook, (probably) because they're feeling lonely in front of the computer screen and they want to have interaction with someone.

Anyways, the effect of this constant fb use and aline social networks is clear. If in the company the employeed personal has to do work on the computer or behind any Internet plugged device, a big time of the use of the device is being 'invested' in facebook to kill some time instead of investing the same time for innovation within the company or doing the assigned tasks in the best possible way

Even those who use facebook occasionally from their work place (by occasionally I mean when they don't have any work to do on the work place), they are constantly distracted (focus on work stealed) by the hanging opened browser window and respectively, when it comes to do some kind of work their work efficiency drops severely.
You might wonder how do I know that facebook opened browser tab would have bad interaction with the rest of the employee work. Well let me explain. Its a well known scientifically proven fact that the human mind is not designed to do simultaneously multiple tasks (we're not computers, though even computers doesn't work perfect when simultaneous tasks are at hand.).
Therefore using facebook in parallel with their daily job most people nowdays try to "multi task" their job and hence this reflects in poor work productivity per employee. The chain result cause of the worsened productivity per employee is therefore seen in the end of the fiscal quarter or fiscal year in bad productivity levels, bad or worsened quality of product and hence to poor financial fiscal results.

I've worked before some time for company whose CEO has realized that the use of certain Internet resources like facebook, gmail and yahoo mail – hurts the employee work productivity and therefore the executive directors asked me to filter out facebook, GMAIL and mail.yahoo as well as few other website which consumed a big portion of the employees time …
Well apparantly this CEO was smart and realized the harm this internet based resources done to his business. Nowdays however many company head executives did not realize the bad effect of the heavy use of public internet services on their work force and never ask the system administrator to filter out this "employees efficiency thefts".

I hope this article, will be eventually red by some middle or small sized company with deteriorating efficiency and this will motivate some companies to introduce an anti-facebook and gmail use policy to boost up the company performance.

As one can imagine, if you sum up all the harm all around the world to companies facebook imposed by simply exposing the employees to do facebooking and not their work, this definitely worsenes the even severe economic crisis raging around …
The topic of how facebook use destroyes many businesses is quite huge and actually probably I'm missing a lot of hardmful aspects to business that can be imposed by just a simple "innocent facebook use", so I will be glad to hear from people in comments, if someone at all benefits of facebook use in an company office (I seriously doubt there is even one).

Suppose you are a company that does big portion of their job behind a computer screen over the internet via a Software as a Service internet based service, suppose you have a project deadline you have to match. The project deadline is way more likely to be matched if you filter out facebook.
Disabling access to facebook of employees and adding company policy to prohibit social network use and rules & regulations prohibiting time consuming internet spaces should produce good productivity results for company lightly.
Though still the employees can find a way to access their out of the job favourite internet services it will be way harder.
If the employee work progress is monitored by installed cameras, there won't be much people to want to cheat and use Facebook, Gmail or any other service prohibited by the company internal codex

Though this are a draconian measures, my personal view is that its better for a company to have such a policy, instead of pay to their emloyees to browser facebook….

I'm not aware what is the situation within many of the companies nowdays and how many of them prohibit the fb, hyves, google plus and the other kind of "anti-social" networks.
But I truly hope more and more organizations chairman / company management will comprehend the damages facebook makes to their business and will issue a new policy to prohibit the use of facebook and the other alike shitty services.

In the mean time for those running an organization routing its traffic through a GNU / Linux powered router and who'd like to prohibit the facebook use to increase the company employees efficiency use this few lines of bash code + iptables:

#!/bin/sh
# Simple iptables firewall rules to filter out www.facebook.com
# Leaving www.facebook.com open from your office will have impact on employees output ;)
# Written by hip0
# 05.03.2012
get_fb_network=$(whois 69.63.190.18|grep CIDR|awk '{ print $2 }');
/sbin/iptables -A OUTPUT -p tcp -d ${get_fb_network} -j DROP

Here is also the same filter out facebook, tiny shell script / blocks access to facebook script

If the script logic is followed I guess facebook can be disabled on other company networks easily if the router is using CISCO, BSD etc.
I will be happy to hear if someone did a research on how much a company efficiency is increased whether in the company office facebook gets filtered out. My guess is that efficiency will increase at least with 30% as a result of prohibition of just facebook.

Please drop me a comment if you have an argument against or for my thesis.

How to install OpenNTPD NTP server to synchronize system clock on FreeBSD for better security

Sunday, February 12th, 2012

FreeBSD, OpenBSD, NetBSD and Linux ntpd alternative server to synchronize server system time

Lately I've been researching on ntpd and wrote a two articles on how to install ntpd on CentOS, Fedora and how to install ntpd on FreeBSD and during my research on ntpd, I've come across OpenNTPD and decided to give it a go on my FreeBSD home router.
OpenBSD project is well known for it is high security standards and historically has passed the test of time for being a extraordinary secure UNIX like free operating system.
OpenBSD is developed in parallel with FreeBSD, however the development model of the two free operating systems are way different.

As a part of the OpenBSD to be independant in its basis of software from other free operating systems like GNU / Linux and FreeBSD. They develop the all around free software realm known OpenSSH. Along with OpenSSH, one interesting project developed for the main purpose of OpenBSD is OpenNTPD.

Here is how openntpd.org describes OpenNTPD:

"a FREE, easy to use implementation of the Network Time Protocol. It provides the ability to sync the local clock to remote NTP servers and can act as NTP server itself, redistributing the local clock."

OpenNTPD's accent just like OpenBSD's accent is security and hence for FreeBSD installs which targets security openntpd might be a good choice. Besides that the so popular classical ntpd has been well known for being historically "insecure", remote exploits for it has been released already at numerous times.

Another reason for someone to choose run openntpd instead of ntpd is its great simplicity. openntpd configuration is super simple.

Here are the steps I followed to have openntpd time server synchronize clock on my system using other public accessible openntpd servers on the internet.

1. Install openntpd through pkg_add -vr openntpd or via ports tree

a) For binar install with pkg_add issue:

freebsd# pkg_add -vr openntpd
...

b) if you prefer to compile it from source

freebsd# cd /usr/ports/net/openntpd
freebsd# make install clean
...

2. Enable OpenNTPD to start on system boot:

freebsd# echo 'openntpd_enable="YES"' >> /etc/rc.conf

3. Create openntpd ntpd.conf configuration file

There is a default sample ntpd.conf configuration which can be straight use as a conf basis:

freebsd# cp -rpf /usr/local/share/examples/openntpd/ntpd.conf /usr/local/etc/ntpd.conf

Default ntpd.conf works just fine without any modifications, if however there is a requirement the openntpd server to listen and accept time synchronization requests from only certain hosts add to conf something like:

listen on 192.168.1.2
listen on 192.168.1.3
listen on 2607:f0d0:3001:0009:0000:0000:0000:0001
listen on 127.0.0.1

This configuration will enable only 192.168.1.2 and 192.168.1.3 IPv4 addresses as well as the IPv6 2607:f0d0:3001:0009:0000:0000:0000:0001 IP to communicate with openntpd.

4. Start OpenNTPD service

freebsd# /usr/local/etc/rc.d/openntpd

5. Verify if openntpd is up and running

freebsd# ps axuww|grep -i ntp
root 31695 0.0 0.1 3188 1060 ?? Ss 11:26PM 0:00.00 ntpd: [priv] (ntpd)
_ntp 31696 0.0 0.1 3188 1140 ?? S 11:26PM 0:00.00 ntpd: ntp engine (ntpd)
_ntp 31697 0.0 0.1 3188 1088 ?? S 11:26PM 0:00.00 ntpd: dns engine (ntpd)
root 31700 0.0 0.1 3336 1192 p2 S+ 11:26PM 0:00.00 grep -i ntp

Its also good idea to check if openntpd has succesfully established connection with its peer remote openntpd time servers. This is necessery to make sure pf / ipfw firewall rules are not preventing connection to remote 123 UDP port:

freebsd# sockstat -4 -p 123
USER COMMAND PID FD PROTO LOCAL ADDRESS FOREIGN ADDRESS
_ntp ntpd 31696 4 udp4 83.228.93.76:54555 212.70.148.15:123
_ntp ntpd 31696 6 udp4 83.228.93.76:56666 195.69.120.36:123
_ntp ntpd 31696 8 udp4 83.228.93.76:49976 217.75.140.188:123

By default openntpd is also listening to IPv6 if IPv6 support is enabled in freebsd kernel.

6. Resolve openntpd firewall filtering issues

If there is a pf firewall blocking UDP requests to in/out port 123 within /etc/pf.conf rule like:

block in log on $EXT_NIC proto udp all

Before the blocking rule you will have to add pf rules:

# Ipv4 Open outgoing port TCP 123 (NTP)
pass out on $EXT_NIC proto tcp to any port ntp
# Ipv6 Open outgoing port TCP 123 (NTP)
pass out on $EXT_NIC inet6 proto tcp to any port ntp
# Ipv4 Open outgoing port UDP 123 (NTP)
pass out on $EXT_NIC proto udp to any port ntp
# Ipv6 Open outgoing port UDP 123 (NTP)
pass out on $EXT_NIC inet6 proto udp to any port ntp

where $EXT_NIC is defined to be equal to the external lan NIC interface, for example:
EXT_NIC="ml0"

Afterwards to load the new pf.conf rules firewall has to be flushed and reloaded:

freebsd# /sbin/pfctl -f /etc/pf.conf -d
...
freebsd# /sbin/pfctl -f /etc/pf.conf -e
...

In conclusion openntpd should be more secure than regular ntpd and in many cases is probably a better choice.
Anyhow bear in mind on FreeBSD openntpd is not part of the freebsd world and therefore security updates will not be issued directly by the freebsd dev team, but you will have to regularly update with the latest version provided from the bsd ports to make sure openntpd is 100% secure.

For anyone looking for more precise system clock synchronization and not so focused on security ntpd might be still a better choice. The OpenNTPD's official page states it is designed to reach reasonable time accuracy, but is not after the last microseconds.
 

How to configure NTP server (ntpd) to synchronize server clock over the Internet on FreeBSD

Friday, February 10th, 2012

 

FreeBSD ntpd logo / How to configure ntpd to synchronize with internet time servers on FreeBSD

On FreeBSD ntpd , ntpdc , ntpdate , ntpq doesn't need to be installed via a specific package like on GNU/Linux as they're part of the FreeBSD world (binary standardly shipped with FreeBSD basis system).

The FreeBSD handbook has a chapter explaining thoroughfully on ntp on FreeBSD ,however for the lazy ones here is a short few steps tutorial on how to install and configure ntpd on bsd :

1. Copy sample ntp.conf file to /etc/

freebsd# cp -rpf /usr/src/etc/ntp.conf /etc/ntp/

No need for any modifications if you don't want to apply some specific restrictions on whom can access the ntpd server. If you update regularly the FreeBSD system with freebsd-update or directly by rebuilding the FreeBSD kernel / world adding restrictions might be not necessery..

If you check /usr/src/etc/ntp.conf you will notice freebsd project people are running their own ntp servers , by default ntpd will use this servers to fetch timing information. The exact server hosts which as of time of writting are used can be seen in ntp.conf and are:

server 0.freebsd.pool.ntp.org iburst maxpoll 9
server 1.freebsd.pool.ntp.org iburst maxpoll 9
server 2.freebsd.pool.ntp.org iburst maxpoll 9

2. Add ntpd daemon to load on system boot via /etc/rc.conf

By default ntpd is disabled on FreeBSD, you can see if it is disabled or enabled by invoking:

freebsd# /etc/rc.d/ntpd rcvar
# ntpd
ntpd_enable=NO

To Enable ntpd to get loaded each time it boots , following 3 lines has to be added in /etc/rc.conf .

ntpdate_enable="YES"
ntpdate_flags="europe.pool.ntp.org"
ntpd_enable="YES"

Quick way to add them is to use echo :

echo 'ntpdate_enable="YES" >> /etc/rc.conf
echo 'ntpdate_flags="europe.pool.ntp.org" >> /etc/rc.conf
echo 'ntpd_enable="YES" >> /etc/rc.conf

Now as the 3 rc.conf vars are set to "YES", the ntpd can be started. Without having this variables in /etc/rc.conf , "/etc/rc.d/ntpd start" will refuse to start ntpd.

3. Start the ntpd service

freebsd# /etc/rc.d/ntpd start
...

One interesting note to make is ntpd can also operate without specifying any config file (/etc/ntp.conf), the only requirement for the server to start is to have a properly set ntpdate server, like lets say (ntpdate_flags="europe.pool.ntp.org")

4. Permit only certain host or localhost to "talk" to the ntpd server

If you want to imply some ntp server restrictions, the configuration directives are same like on Linux:

To allow only a a host inside a local network with IP 192.168.0.2 as well as localhost, to be able to fetch time information via ntpd server put inside /etc/ntp.conf:

restrict 127.0.0.1
restrict 192.168.0.1 mask 255.255.255.0 nomodify notrap

If you want to prohibit ntpd to serve as a Network Time Server, to any other host except localhost, add in /etc/ntp.conf :

restrict default ignore

Allowing and denying certain hosts can be also done on pf (packet filter) or ipfw firewall level, and in my view is easier (and less confusing), than adding restrictions through ntp.conf. Besides that using directly the server firewall to apply restrictions is more secure. If for instance a remote exploit vulnerability is discovered affecting your ntpd server. this will not affect you externally as access to the UDP port 123 will be disabled on a firewall level.
Something good to mention is NTP servers communicate between each other using the UDP source/destination (port 123). Hence if the NTPD server has to be publicly accessible and there is a firewall already implemented, access to source/dest port 123 should be included in the configured firewall …

5. Check if the ntp server is running properly / ntp server query operations

[root@pcfreak /home/hipo]# ps axuww|grep -i ntp
root 15647 0.0 0.2 4672 1848 ?? Ss 2:49PM 0:00.04 /usr/sbin/ntpd -c /etc/ntp.conf -p /var/run/ntpd.pid -f /var/db/ntpd.drift

To query the now running ntpd server as well as set various configuration options "on the fly" (e.g. without need for ntp.conf edits and init script restart), a tool called ntpdc exists. ntpdc tool could be used to connect to localhost running ntpd as well as to connect and manage remotely a ntpd server.
The most basic use of ntpdc is to check (server peers).:
freebsd# ntpdc localhost
ntpdc> peers
remote local st poll reach delay offset disp
===================================================

kgb.comnet.bg 83.228.93.76 2 64 377 0.00282 -0.050575 0.06059
*billing.easy-la 83.228.93.76 2 64 377 0.01068 -0.057400 0.06770
=ns2.novatelbg.n 83.228.93.76 2 64 377 0.01001 -0.055290 0.06058

ntpdc has also a non-interactive interface, handy if there is a need for requests to a ntpd to be scripted. To check ntpd server peers non-interactively:

freebsd# ntpdc -p localhost
===================================================
kgb.comnet.bg 83.228.93.76 2 64 377 0.00284 -0.043157 0.06184
=billing.easy-la 83.228.93.76 2 64 377 0.01059 -0.042648 0.05811
*ns2.novatelbg.n 83.228.93.76 2 64 377 0.00996 -0.041097 0.06094

ntpdc has plenty of other ntpd query options, e.g. :

ntpdc> help
ntpdc commands:
addpeer controlkey fudge keytype quit timeout
addrefclock ctlstats help listpeers readkeys timerstats
addserver debug host loopinfo requestkey traps
addtrap delay hostnames memstats reset trustedkey
authinfo delrestrict ifreload monlist reslist unconfig
broadcast disable ifstats passwd restrict unrestrict
clkbug dmpeers iostats peers showpeer untrustedkey
clockstat enable kerninfo preset sysinfo version
clrtrap exit keyid pstats sysstats

ntpdc is an advanced query tool for ntpd , servers. Another tool exists called ntpq which syntax is almost identical to ntpdc . The main difference between the two is ntpq is a monitoring tool mostly used just for monitoring purposes, where ntpdc can also change plenty of things in the server configuration.

For people who want to learn more on ntpd the man page is a great reading , containing chapters describing thoroughfully exactly how NTPD time servers operate, etc.

Test your web browser compatability with Acid3 test

Wednesday, January 25th, 2012

Acid3 Test is a group of browser compitability tests. Acid3 test is a good indicator on how Web ready is your browser.

Acidtest is part of the web standards project. Latest Firefox 9.0.1 passes the test on 100% (100/100).
I've tried it with Epiphany and it scored only 67/100, still I'm using Epiphany on daily basis and I'm quite happy with it.
Acid3 browser compitability Test Firefox 9.0.1
The tests involved are testing browser for:
 

  • DOM
  • DOM2
  • Checks on HTML tables and forms browser rendering
  • SVG compitability testing
  • DOM1 and DOM2 compitability
  • Various ECMA Script Javascript compitability tests
  • Unicode (UTF-16 and UTF-8) browser compitability
  • XHML, SMIL, CSS, HTML compitability
  • Content-type image/png, text plain etc.

Acid3 browser test fail
The Acid3 test is written itself in Javascript. It consists of 6 testing "stages" (buckets) upon which the browser tested is evaluated.
Each of the test is represented visually by a rectangle. If the a test stage is passed you see a new rectangle appearing in the tested browser.
In wikipedia, there is a thorough list with web browsers by type and engine and the level of support for the Acid3 test.
The test is of great use if you're web developer.

How to set a crontab to execute commands on a seconds time interval on GNU / Linux and FreeBSD

Sunday, October 30th, 2011

crontab-execute-cron-jobs-every-second-on-linux-cron-logo
Have you ever been in need to execute some commands scheduled via a crontab, every let’s say 5 seconds?, naturally this is not possible with crontab, however adding a small shell script to loop and execute a command or commands every 5 seconds and setting it up to execute once in a minute through crontab makes this possible.
Here is an example shell script that does execute commands every 5 seconds:

#!/bin/bash
command1_to_exec='/bin/ls';
command2_to_exec='/bin/pwd';
for i in $(echo 1 2 3 4 5 6 7 8 9 10 11); do
sleep 5;
$command1_to_exec; $command2_to_exec;
done

This script will issue a sleep every 5 seconds and execute the two commands defined as $command1_to_exec and $command2_to_exec

Copy paste the script to a file or fetch exec_every_5_secs_cmds.sh from here

The script can easily be modified to execute on any seconds interval delay, the record to put on cron to use with this script should look something like:

# echo '* * * * * /path/to/exec_every_5_secs_cmds.sh' | crontab -

Where of course /path/to/exec_every_5_secs_cmds.sh needs to be modified to a proper script name and path location.

Another way to do the on a number of seconds program / command schedule without using cron at all is setting up an endless loop to run/refresh via /etc/inittab with a number of predefined commands inside. An example endless loop script to run via inittab would look something like:

while [ 1 ]; do
/bin/ls
sleep 5;
done

To run the above sample never ending script using inittab, one needs to add to the end of inittab, some line like:

mine:234:respawn:/path/to/script_name.sh

A quick way to add the line from consone would be with echo:

echo 'mine:234:respawn:/path/to/script' >> /etc/inittab

Of course the proper paths, should be put in:

Then to load up the newly added inittab line, inittab needs to be reloaded with cmd:

# init q

I've also red, some other methods suggested to run programs on a periodic seconds basis using just cron, what I found in stackoverflow.com's  as a thread proposed as a solution is:

* * * * * /foo/bar/your_script
* * * * * sleep 15; /foo/bar/your_script
* * * * * sleep 30; /foo/bar/your_script
* * * * * sleep 45; /foo/bar/your_script

One guy, even suggested a shorted way with cron:

0/15 * * * * * /path/to/my/script

The creator of C and UNIX Dennis Ritchie passed away R.I.P. Dennis

Thursday, October 13th, 2011

Dennis Ritchie old young picture

I just read the lwn.net – Linux Weekly news ‘s website the very sad news that one of the greatest modern day computer heroes Dennis MacAlistair Ritchie after a long illness has passed away in his home.

The original notification for this grieving news are on Rob Pike’s Google Plus wall , this is the original message:

Rob Pike - 1:02 AM - Public
I just heard that, after a long illness, Dennis Ritchie (dmr) died at home this weekend. I have no more information.
I trust there are people here who will appreciate the reach of his contributions and mourn his passing appropriately.
He was a quiet and mostly private man, but he was also my friend, colleague, and collaborator, and the world has lost a truly great mind.

For all those who haven’t heard about Dennis Ritchie , he was a computer scientist who developed the C Programming language and had an immeasurable influence on all kind of Modern programming.

C Programming Language cover Dennis Ritchie

Dennis worked on the development of Unix’s predecessor Multics as well as with Ken Thompson worked together in Bell Labs and are practically the fathers of UNIX.
Unix the Seventh Edition source code has later become the basis for the early UNIX BSD distributions. Among the most important technical contributions Dennis has done is the introduction of a Streams mechanism – pipes – (as called today in GNU/Linux and BSD and other unices).
Ritchie’s C Language creation on top of Ken Thompson’s B Programming language has been standartized and become the de-facto standard for almost every modern existing OS around.
Moreover dmr has been among the co-creators of Plan 9 Operating system (which is currently open-source distributed) as well as coded a few bits for the Inferno OS which today is known under the code name Vita Nuova

Unix Live Free or die Bell labs early UNIX logo

dmr (the hacker nickname of Dennis) lines up across the most notable computer hackers of all times. He received U.S. national Medal of Technology in 1999 from president Bill Clinton for his contributions to co-inventing the UNIX operating system and the creation of C Language

Denis Ritchie receives national prize in 1999 for Technology from president Bill Clinton
To sum it up DMR is just an “icon” in the computer geek world and his memory will surely live forever in the hacker undeground and computer geek culture.

Dennis Ritche near a personal computer picture

A few quotes dmr is so famous with:

"I am not now, nor have I ever been, a member of the demigodic party."
"Usenet is a strange place."
"UNIX is very simple, it just needs a genius to understand its simplicity."
"C is quirky, flawed, and an enormous success."
"We really didn't buy it thinking we'd have this enormous investment."

Here is also a short video telling a few words of UNIX history and showing Dennis Ritchie in his UNIX development years:

Farewell Denis! See you in Hacker’s paradise 😉

Filter messages in Qmail with unwanted words, get rid of the Viagra annoying spam with Qtrap

Sunday, September 4th, 2011

Drop qmail received mail containing banned / unwanted words to get rid of Viagra and Sex related spam

Recently the annoying Viagra spam has emerged again. Therefore I decided to clean up some of the mails received to one of the qmail servers to protect users emailbox from this viagra peril.

To do so I’ve remember about an old script which used to be part of qmailrocks.org qmail install, the script is called qtrap and is able to filter emails based on list of specific mail contained words.
Since qmailrocks.org is gone (down) for some time and its still available only on few mirrored locations which by the way are not too easy to find I decided to write a little post on how qtrap.sh could be integrated quick & easy with any Qmail + Vpopmail install out there.

Hereby I include the description for qtrap.sh given by the script author:

“qtrap.sh script is applied on a per domain basis and serves as a “bad word” scanner to catch any spam that Spamassassin may have missed. This filter serves as the last defense against SPAM before it arrived in your inbox. I like this filter because it helps to get rid of any SPAM that happens to make it by Spamassassin. Without any protection at all, my mailbox gets a shit ton of SPAM every day. Within the first 3 months I enacted the Qtrap filter, Qtrap logged over 9,000 deleted SPAM messages, none of which were legitimate e-mails. My keyboard’s delete key was very appreciated the extra rest.

Any emails that are scanned and contain a banned word will be automatically deleted and logged by the qtrap script. A whitelist feature now exists so that individual addresses or domains can be exempt from the qtrap scan.”

Now as one might have general idea on what the script does. Here is the step by step qtrap.sh integration;

1. Create necessery qtrap directory and logs and set proper permissions

If the vpopmail is installed in /home/vpopmail , issue the following commands.

debian:~# cd /home/vpopmail
debian:~# mkdir -p qtrap/logs
debian:/home/vpopmail/qtrap# cd qtrap
debian:/home/vpopmail/qtrap# wget http://www.pc-freak.net/files/qtrap.sh
...
debian:/home/vpopmail/qtrap# cd ~
debian:~# touch /home/vpopmail/qtrap/logs/qtrap.logdebian:~# chown -R vpopmail:vchkpw /home/vpopmail/qtrapdebian:~# chmod -R 755 /home/vpopmail/qtrap

On older qmail installations it could be vpopmail is installed in /var/vpopmail if that’s the case, link /var/vpopmail to /home/vpopmail and go back to step 1. To link:

debian:~# ln -sf /var/vpopmail/ /home/vpopmail

2. Edit qtrap.sh to whitelist email addresses and build a ban words list

a) Include the email addresses mail arriving from which would not be checked by qtrap.sh

Inside qtrap.sh in line 63, there is a shell function whitelist_check(), the function looks like so:

whitelist_check () {
case $WHITELIST in
address@somewhere.com|address@somewhereelse.com)
echo $SENDER found in whitelist on `date "+%D %H:%M:%S"` >> /home/vpopmail/qtrap/logs/qtrap.log
exit 0;;
*)
;;
esac
}

By default the script has just two sample mails which gets whitelisted this is the line reading:

address@somewhere.com|address@somewhereelse.com

The whitelisted emails should be separated with a pipe, thus to add two more sample emails to get whitelisted by script the line should be changed like:

address@somewhere.com|address@somewhereelse.com|hipod@mymailserver.com|hipo@gmail.com

In order to whitelist an entire domain let’s say yahoo.com add a line to the above code like:

address@somewhere.com|address@somewhereelse.com|hipod@mymailserver.com|hipo@gmail.com|*yahoo.com

b) Defining the bad words ban list, mails containing them should not be delivery by qmail

The function that does check for the ban word list inside the script is checkall();, below is a paste from the script function:

checkall () {
case $BANNED_WORDS in
porn|PORN|Sex|SEX)
printout $BANNED_WORDS
echo MESSAGE DROPPED from $SENDER because of $BANNED_WORDS on `date "+%D %H:%M:%S"` >> /home/vpopmail/qtrap/logs/qtrap.log
exit 99;;
*)
;;
esac
}

checkall(); is located on line 74 in qtrap.sh, the exact list of banned words which the script should look for is located on line 76, the default qtrap.sh filters only mails containing just 4 words, e.g.:

porn|PORN|Sex|SEX)

To add the Viagra and VIAGRA common spam words to the list, modify it and expand like so:

porn|PORN|Sex|SEX|viagra|Viagra)

The delimiter is again | , so proceed further and add any unwanted spam words that are not common for any legit mails.

3. Install qtrap.sh to process all emails delivered to vpopmail

If its necessery to install the dropping of mails based on word filtering only to a single vpopmail virtualdomain do it with cmd:

debian:~# cd /home/vpopmail/domains/yourdomain.com
debian:/home/vpopmail/domains/yourdomain.com# touch .qmail-default.new
debian:/home/vpopmail/domains/yourdomain.com# echo '| /home/vpopmail/qtrap/qtrap.sh' >> .qmail-default.new
debian:/home/vpopmail/domains/yourdomain.com# echo "| /home/vpopmail/bin/vdelivermail '' bounce-no-mailbox" >> .qmail-default.new
debian:/home/vpopmail/domains/yourdomain.com# chown vpopmail:vchkpw .qmail-default.new
debian:/home/vpopmail/domains/yourdomain.com# cp -rpf .qmail-default .qmail-default.bak; mv .qmail-default.new .qmail-default
If however qtrap.sh needs to get installed for all existing vpopmail virtualdomains on the qmail server, issue a one liner bash script:

debian:~# cd /home/vpopmail/domains
debian:/var/vpopmail/domains# for i in *; do cd $i; echo "| /home/vpopmail/qtrap/qtrap.sh" >> $i/.qmail-default.new;
echo "| /home/vpopmail/bin/vdelivermail '' bounce-no-mailbox" >> $i/.qmail-default.new;
chown vpopmail:vchkpw .qmail-default.new; mv .qmail-default .qmail-default.old; mv .qmail-default.new .qmail-default; cd ..; done

This for loop will add ‘| /home/vpopmail/qtrap/qtrap.sh’ to all .qmail-default for all vpopmail domains.

Afterwards the .qmail-default file should contain the following two lines:

| /home/vpopmail/qtrap/qtrap.sh
| /home/vpopmail/bin/vdelivermail '' delete

A very important thing here you should consider that adding some common words, as let’s say hello or mail etc. could easily drop almost all the emails the qmail hands in to vpopmail.

Caution!! Never ever implement common words in the list of words !!
Always make sure the banned words added to qtrap.sh are words that are never enter an everyday legit email.

Another thing to keep in mind is that qtrap.sh doesn’t make a copy of the received message ,though it can easily be modified to complete this task.
Any mail that matches the banned words list will be dropped and lost forever.

4. Check if qtrap.sh is working

To check, if qtrap is working send mail to some mailbox located on the qmail server containing inside subject or mail message body the unwanted word defined inside qtrap.sh.

The mail should not be received in the mailbox to which its sent, if qtrap is working moreover qtrap.sh should log it inside it’s log file:

debian:~# cat /home/vpopmail/qtrap/logs/qtrap.log
MESSAGE DROPPED from hipo@mytestmail.com because of viagra on 09/03/11 11:34:19
MESSAGE DROPPED from support@mymailserver.com because of Viagra on 09/03/11 11:39:29

If the qtrap.log contains records similar to the one above, and the mail matching the banned word is not delivered, qtrap.sh is properly configured. If any issues check in qmail logs, they should have a good pointer on what went wrong with qtrap.sh invokation.

Note that I’ve integrated qtrap.sh to custom qmail install running on Debian Lenny 5.0 GNU/Linux.
If I have time I’ll soon test if its working fine on the latest stable Debian Squeeze and will report here in comments.
If however someone is willing to test if the script works on Debian Squeeze 6.0 or have tested it already please drop a comment to report if it works fine.
qtrap.sh, is a bit oldish and is not written to work too optimal therefore on some heavy loaded mail servers it can create some extra load and a bit delay the mail delivery. Thus when implementang one needs to consider the downsides of putting it in.

Also I was thinking tt might be nice if the script is rewritten to read the ban words and whitelist mails from files instead of as it is now as the words are hard coded in the script.
If I have some free time, I’ll probably do this, though I’m not sure if this is a too good idea as this might have a negative performance impact on the script execution time, as each instance of the script invoked should do one more operation of reading a file storing the ban words.

Well that’s pretty much it, enjoy 😉