You are not logged in.

#1 2012-05-14 14:20:55

archkid420
Member
Registered: 2012-05-13
Posts: 20

Arch forum registration question

When registrating, why do they need to know the output of the command:

date -u +%j$(uname) | sha256sum | sed 's/\W//g'

What does it do?


[Arch64 | awesome]

Offline

#2 2012-05-14 14:24:03

65kid
Member
From: Germany
Registered: 2011-01-26
Posts: 663

Re: Arch forum registration question

I guess it's a CAPTCHA

Offline

#3 2012-05-14 14:25:16

archkid420
Member
Registered: 2012-05-13
Posts: 20

Re: Arch forum registration question

oh really? i thought it was getting my system info...


[Arch64 | awesome]

Offline

#4 2012-05-14 14:34:13

Awebb
Member
Registered: 2010-05-06
Posts: 4,545

Re: Arch forum registration question

Run it without the hash to see what it does. It does not gather anything about your computer, so don't worry.

Offline

#5 2012-05-14 15:06:00

ewaller
Administrator
From: Pasadena, CA
Registered: 2009-07-13
Posts: 13,443

Re: Arch forum registration question

archkid420 wrote:

When registrating, why do they need to know the output of the command:

date -u +%j$(uname) | sha256sum | sed 's/\W//g'

What does it do?

65Kid hit the nail on the head.  A while back, the forums were being inundated with bottom feeding spammers.  That little "Test" was put in place to filter out anyone who was not serious about running a Linux system from a command line.  It is certainly over the head of the most of parasites that would spew their garbage on the forums.

Edit:: And no, it does not gather anything.  Note that the input to the hash is the kernel you are running and the date.  Those are fed into the SHA-2 hash which is nothing more than a signature of the input data -- the original inputs cannot be recovered from the hash.  At our end, we know the date, and we know what the kernel is.  We generate a hash of those as well.  If the hash your system provides matches the hash that we generate, your in -- you become part of the club smile

Last edited by ewaller (2012-05-14 15:11:32)


Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
You assume people are rational and influenced by evidence.  You must not work with the public much. -- Trilby
----
How to Ask Questions the Smart Way

Offline

#6 2012-05-14 15:35:23

Trilby
Forum Moderator
From: Massachusetts, USA
Registered: 2011-11-29
Posts: 14,226
Website

Re: Arch forum registration question

And if the hash your system provides doesn't match .... well, you don't want to know what happens to those people.  It's not pretty.

wink


InterrobangSlider
• How's my coding? See this page.
• How's my moderating? Feel free to email any concerns, complaints, or objections.

Offline

#7 2012-05-14 15:39:23

karol
Archivist
Registered: 2009-05-06
Posts: 25,433

Re: Arch forum registration question

The previous registration question wasn't all that easy either ;-)
https://bbs.archlinux.org/viewtopic.php?id=97222

Offline

#8 2012-05-14 15:39:36

Awebb
Member
Registered: 2010-05-06
Posts: 4,545

Re: Arch forum registration question

We once had a dude MD5'ing the date. I still can't get the pictures out of my head.

Offline

#9 2012-05-14 16:06:37

altbdoor
Member
From: KL, Malaysia
Registered: 2012-04-25
Posts: 128

Re: Arch forum registration question

it was funny because i remembered i do not have access to internet on my arch system yet, and i need to ask a question in the forums. when the "captcha" came, i was like wut?

had to read word by word from the screen, type word by word into arch (gosh sure hope the result is short).
oh guess what. one long string of numbers.
had to read number by number from arch, type number by number into pc.

fun and eye-opening experience nevertheless big_smile


Lurking in newbie corner, helping with wireless problems.

Offline

#10 2012-05-14 16:36:25

karol
Archivist
Registered: 2009-05-06
Posts: 25,433

Re: Arch forum registration question

altbdoor wrote:

fun and eye-opening experience nevertheless big_smile

You can use this: https://bbs.archlinux.org/viewtopic.php … 51#p999551 and register from a non-Arch system.

Offline

#11 2012-05-14 21:06:46

nomorewindows
Member
Registered: 2010-04-03
Posts: 3,015

Re: Arch forum registration question

It would definitely be difficult to run that command line from inside Windows!


I may have to CONSOLE you about your usage of ridiculously easy graphical interfaces...
Look ma, no mouse.

Offline

#12 2012-05-14 22:05:26

karol
Archivist
Registered: 2009-05-06
Posts: 25,433

Re: Arch forum registration question

nomorewindows wrote:

It would definitely be difficult to run that command line from inside Windows!

gnu tools for Windows do exist, as does cygwin. You can also fire up a VM with some Linux distro ;P

Offline

#13 2012-05-14 22:07:48

archkid420
Member
Registered: 2012-05-13
Posts: 20

Re: Arch forum registration question

ewaller wrote:

65Kid hit the nail on the head.  A while back, the forums were being inundated with bottom feeding spammers.  That little "Test" was put in place to filter out anyone who was not serious about running a Linux system from a command line.  It is certainly over the head of the most of parasites that would spew their garbage on the forums.

Edit:: And no, it does not gather anything.  Note that the input to the hash is the kernel you are running and the date.  Those are fed into the SHA-2 hash which is nothing more than a signature of the input data -- the original inputs cannot be recovered from the hash.  At our end, we know the date, and we know what the kernel is.  We generate a hash of those as well.  If the hash your system provides matches the hash that we generate, your in -- you become part of the club smile

oh, that's smart smile


[Arch64 | awesome]

Offline

#14 2012-05-14 22:48:21

Xyne
Moderator/TU
Registered: 2008-08-03
Posts: 5,728
Website

Re: Arch forum registration question

karol wrote:
nomorewindows wrote:

It would definitely be difficult to run that command line from inside Windows!

gnu tools for Windows do exist, as does cygwin. You can also fire up a VM with some Linux distro ;P

Doesn't the command expect the output to be "Linux"? What does "uname" return under cygwin?

Regardless, installing a working POSIX environment if you don't have one just to register on a forum is not KISS.


As for blocking bots, it can't be that hard to write a bot to parse the registration page and return the expected output. It only blocks  bots now because no one has targeted this forum specifically.

Offline

#15 2012-05-14 23:07:12

Pierre
Developer
From: Bonn
Registered: 2004-07-05
Posts: 1,950
Website

Re: Arch forum registration question

The problem are not the usual bots, but humans. These days they pay some poor guys a few cents a day to break captchas. I tried all kinds of different questions; problem was they could be easily solved using google or wikipedia.

There is already a lengthy thread with all answers you are looking for; but again: we are targeting competent linux users; so if this test is a little more difficult on windows it's not a real issue.

Anyway, if someone comes up with a better idea that has a similar success rate, let me know. (Questions like "Who created Arch Linux" or "What's the md5sum of the latest ISO" got bypassed after a short time.)

Offline

#16 2012-05-14 23:29:26

nomorewindows
Member
Registered: 2010-04-03
Posts: 3,015

Re: Arch forum registration question

Pierre wrote:

The problem are not the usual bots, but humans. These days they pay some poor guys a few cents a day to break captchas. I tried all kinds of different questions; problem was they could be easily solved using google or wikipedia.

There is already a lengthy thread with all answers you are looking for; but again: we are targeting competent linux users; so if this test is a little more difficult on windows it's not a real issue.

Anyway, if someone comes up with a better idea that has a similar success rate, let me know. (Questions like "Who created Arch Linux" or "What's the md5sum of the latest ISO" got bypassed after a short time.)

I was looking for something on amiga.org forums, and they used those kinds of questions just to use the search function!


I may have to CONSOLE you about your usage of ridiculously easy graphical interfaces...
Look ma, no mouse.

Offline

#17 2012-05-14 23:30:25

jasonwryan
Forum & Wiki Admin
From: .nz
Registered: 2009-05-09
Posts: 19,385
Website

Re: Arch forum registration question

The current approach works. I've yet to see a compelling (or even plausible) reason to change it...


Arch + dwm   •   Mercurial repos  •   Github

Registered Linux User #482438

Offline

#18 2012-05-15 00:54:21

ngoonee
Forum Fellow
From: Between Thailand and Singapore
Registered: 2009-03-17
Posts: 6,856

Re: Arch forum registration question

jasonwryan wrote:

The current approach works. I've yet to see a compelling (or even plausible) reason to change it...

Though I (and I presume jason as well) would be all for a system which is even harder, perhaps involving counting the number of options in our default kernel config set to 'M' smile


Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.

Offline

Board footer

Powered by FluxBB