An encrypting function.

**Peter Fox** · Jan 25 '06, 12:25 AM

Re: An encrypting function.

Following on from frizzle's message. . .[color=blue]
>Hi there,
>
>I need an encrypting function, but haven't got a clue where to start.[/color]
Ummm...yes - where to start.

I can't help feeling that you are not using the right method to do what
you're /really/ trying to achieve. If something is getting re-inputted
then why bother? If you want random numbers then you can generate
random strings with rand and md5 functions *and check input against
session vars* or values regenerated from a database seed.

There's an easy way to avoid o0 etc and that's by replacing one with
a distinctive character. NB 5s, 8B,1L,4A - many screens don't tell you.

I have a hunch you're trying too hard, but without a clearer idea of
what you're trying to do can't go further.

[color=blue]
>First a string has to be encrypted with two different encryption keys.
>Both output should be anything a-z / A-Z / 0-9 with a fixed length
>(e.g. 20 chars).
>(Preferably the encryption keys should pick chars from a string i give
>them,
>to prevent l's and 1's, o's and 0's etc.)
>
>Then they get inputted again ( say $_POST['name'] and $_POST['code'] )
>and i have to decrypt them. I know $_POST['name'] should use
>decode/encode-key 1,
>and $_POST['code'] should use decode/encode-key 2.
>
>
>Decoded they should be the same again.
>(Example below.)
>
>I hope it's kind of clear ...
>
>Greetings frizzle.
>
>
>-------- EXAMPLE --------
>
>Input : foobar
>
>Output key 1 : klKpUR867Biwr74 2gsBd
>Output key 2 : 9KdfnbDSnd65sgh 45hsd
>
>$_POST['name'] : klKpUR867Biwr74 2gsBd
>$_POST['code'] : 9KdfnbDSnd65sgh 45hsd
>
>Result : foobar ( $_POST['name'] === $_POST['code'] )
>[/color]

--
PETER FOX Not the same since the porcelain business went down the pan
peterfox@eminen t.demon.co.uk.n ot.this.bit.no. html
2 Tees Close, Witham, Essex.
Gravity beer in Essex <http://www.eminent.dem on.co.uk>

**Carl Vondrick** · Jan 25 '06, 12:45 AM

Re: An encrypting function.

You may want to look into Mcrypt
(http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
what are you really try to achieve?

**Iván Sánchez Ortega** · Jan 25 '06, 01:15 AM

Re: An encrypting function.

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

frizzle wrote:
[color=blue]
> Hi there,
>
> I need an encrypting function, but haven't got a clue where to start.[/color]

Maybe by RTFM?

PHP: Mcrypt Functions - Manual

http://php.net/manual/en/ref.mcrypt.php

Mcrypt Functions

- --
- ----------------------------------
Iván Sánchez Ortega -i-punto-sanchez--arroba-mirame-punto-net

http://acm.asoc.fi.upm.es/~mr/

Proudly running Debian Linux with 2.6.12-1-686 kernel, KDE3.5.0, and PHP
5.1.2-1 generating this signature.
Uptime: 01:22:27 up 4:11, 1 user, load average: 0.57, 0.31, 0.18

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)

iD8DBQFD1sTm3jc Q2mg3Pc8RAiC0AJ 9nMHtEv24XBLrO5 aWnTIvc940TswCe PFOj
AscAJ7+AFeXveYK rlY+iNOo=
=7Y0o
-----END PGP SIGNATURE-----

**Chung Leong** · Jan 25 '06, 01:45 AM

Re: An encrypting function.

Crypt_Blowfish

http://pear.php.net/package/Crypt_Blowfish

**frizzle** · Jan 25 '06, 10:25 PM

Re: An encrypting function.

Carl Vondrick wrote:[color=blue]
> You may want to look into Mcrypt
> (http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
> what are you really try to achieve?[/color]

What i'm trying to do is build a way of security that a human is
submitting a form.
I know there are ways out there already, but i also have other purposes
in mind.

Example:

Image random generated according to key 1:

image.php?txt=k jGKUGFfas8gkjaf Kfasdf

The image is a php file, getting $_GET['txt'], decrypt it according
key 1, and encrypt it according to key 2. The second encrypting
becomes visible in the actual image.

I have a have a hidden form field with the value of key 1, and the
visitor has to insert the text from the image / key 2 into a form
field.

Then after posting i compare the decrypted hidden formfield's value
against the user submitted value ( / image's value). if they match,
the user read the image, and is human ...

It might sound stupid, sloppy or whatever, but i'm just trying to
achieve my goal.

Thanks.

**Jim Michaels** · Feb 7 '06, 08:15 AM

Re: An encrypting function.

"frizzle" <phpfrizzle@gma il.com> wrote in message
news:1138227180 .394441.177630@ z14g2000cwz.goo glegroups.com.. .[color=blue]
> Carl Vondrick wrote:[color=green]
>> You may want to look into Mcrypt
>> (http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
>> what are you really try to achieve?[/color]
>
> What i'm trying to do is build a way of security that a human is
> submitting a form.
> I know there are ways out there already, but i also have other purposes
> in mind.
>
> Example:
>
> Image random generated according to key 1:
>
> image.php?txt=k jGKUGFfas8gkjaf Kfasdf
>
> The image is a php file, getting $_GET['txt'], decrypt it according
> key 1, and encrypt it according to key 2. The second encrypting
> becomes visible in the actual image.
>
> I have a have a hidden form field with the value of key 1, and the
> visitor has to insert the text from the image / key 2 into a form
> field.
>
> Then after posting i compare the decrypted hidden formfield's value
> against the user submitted value ( / image's value). if they match,
> the user read the image, and is human ...[/color]

Not sure, but sounds like a CAPTCHA. They can be OCR'd
(http://www.ocr-research.org.ua/ ) from what I found in an earlier post.
[color=blue]
>
> It might sound stupid, sloppy or whatever, but i'm just trying to
> achieve my goal.
>
> Thanks.
>[/color]

**frizzle** · Feb 7 '06, 09:35 AM

Re: An encrypting function.

Thanks, indeed that's what i meant.
Apparently it's a weaker system then i imagined.
I guess i'll have to find another alternative again ... :(

Greetings Frizzle.

Jim Michaels wrote:[color=blue]
> "frizzle" <phpfrizzle@gma il.com> wrote in message
> news:1138227180 .394441.177630@ z14g2000cwz.goo glegroups.com.. .[color=green]
> > Carl Vondrick wrote:[color=darkred]
> >> You may want to look into Mcrypt
> >> (http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
> >> what are you really try to achieve?[/color]
> >
> > What i'm trying to do is build a way of security that a human is
> > submitting a form.
> > I know there are ways out there already, but i also have other purposes
> > in mind.
> >
> > Example:
> >
> > Image random generated according to key 1:
> >
> > image.php?txt=k jGKUGFfas8gkjaf Kfasdf
> >
> > The image is a php file, getting $_GET['txt'], decrypt it according
> > key 1, and encrypt it according to key 2. The second encrypting
> > becomes visible in the actual image.
> >
> > I have a have a hidden form field with the value of key 1, and the
> > visitor has to insert the text from the image / key 2 into a form
> > field.
> >
> > Then after posting i compare the decrypted hidden formfield's value
> > against the user submitted value ( / image's value). if they match,
> > the user read the image, and is human ...[/color]
>
> Not sure, but sounds like a CAPTCHA. They can be OCR'd
> (http://www.ocr-research.org.ua/ ) from what I found in an earlier post.
>[color=green]
> >
> > It might sound stupid, sloppy or whatever, but i'm just trying to
> > achieve my goal.
> >
> > Thanks.
> >[/color][/color]

**Jerry Stuckle** · Feb 7 '06, 11:15 AM

Re: An encrypting function.

frizzle wrote:[color=blue]
> Thanks, indeed that's what i meant.
> Apparently it's a weaker system then i imagined.
> I guess i'll have to find another alternative again ... :(
>
> Greetings Frizzle.
>
>
> Jim Michaels wrote:
>[color=green]
>>"frizzle" <phpfrizzle@gma il.com> wrote in message
>>news:11382271 80.394441.17763 0@z14g2000cwz.g ooglegroups.com ...
>>[color=darkred]
>>>Carl Vondrick wrote:
>>>
>>>>You may want to look into Mcrypt
>>>>(http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
>>>>what are you really try to achieve?
>>>
>>>What i'm trying to do is build a way of security that a human is
>>>submitting a form.
>>>I know there are ways out there already, but i also have other purposes
>>>in mind.
>>>
>>>Example:
>>>
>>>Image random generated according to key 1:
>>>
>>> image.php?txt=k jGKUGFfas8gkjaf Kfasdf
>>>
>>>The image is a php file, getting $_GET['txt'], decrypt it according
>>>key 1, and encrypt it according to key 2. The second encrypting
>>>becomes visible in the actual image.
>>>
>>>I have a have a hidden form field with the value of key 1, and the
>>>visitor has to insert the text from the image / key 2 into a form
>>>field.
>>>
>>>Then after posting i compare the decrypted hidden formfield's value
>>>against the user submitted value ( / image's value). if they match,
>>>the user read the image, and is human ...[/color]
>>
>>Not sure, but sounds like a CAPTCHA. They can be OCR'd
>>(http://www.ocr-research.org.ua/ ) from what I found in an earlier post.
>>
>>[color=darkred]
>>>It might sound stupid, sloppy or whatever, but i'm just trying to
>>>achieve my goal.
>>>
>>>Thanks.
>>>[/color][/color]
>
>[/color]

Why? Is this a high security site?

OCR'ing CAPTCHA images does take time and effort - each one is typically
different. What would be on your site which would require that much effort?

Not to denigrate your site in any form - but the fact is, spammers
et.al. wouldn't bother with 99.99999% of the CAPTCHA images. They'll
just go onto another site.

It's like your front door. Your lock isn't unpickable - it just
requires time and effort on a burglar's part to pick. However, you lock
your door anyway, because it's a deterrent - the burglar will most
likely move on (unless you're storing Fort Knox inside).

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

**frizzle** · Feb 7 '06, 12:05 PM

Re: An encrypting function.

Jerry Stuckle wrote:[color=blue]
> frizzle wrote:[color=green]
> > Thanks, indeed that's what i meant.
> > Apparently it's a weaker system then i imagined.
> > I guess i'll have to find another alternative again ... :(
> >
> > Greetings Frizzle.
> >
> >
> > Jim Michaels wrote:
> >[color=darkred]
> >>"frizzle" <phpfrizzle@gma il.com> wrote in message
> >>news:11382271 80.394441.17763 0@z14g2000cwz.g ooglegroups.com ...
> >>
> >>>Carl Vondrick wrote:
> >>>
> >>>>You may want to look into Mcrypt
> >>>>(http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
> >>>>what are you really try to achieve?
> >>>
> >>>What i'm trying to do is build a way of security that a human is
> >>>submitting a form.
> >>>I know there are ways out there already, but i also have other purposes
> >>>in mind.
> >>>
> >>>Example:
> >>>
> >>>Image random generated according to key 1:
> >>>
> >>> image.php?txt=k jGKUGFfas8gkjaf Kfasdf
> >>>
> >>>The image is a php file, getting $_GET['txt'], decrypt it according
> >>>key 1, and encrypt it according to key 2. The second encrypting
> >>>becomes visible in the actual image.
> >>>
> >>>I have a have a hidden form field with the value of key 1, and the
> >>>visitor has to insert the text from the image / key 2 into a form
> >>>field.
> >>>
> >>>Then after posting i compare the decrypted hidden formfield's value
> >>>against the user submitted value ( / image's value). if they match,
> >>>the user read the image, and is human ...
> >>
> >>Not sure, but sounds like a CAPTCHA. They can be OCR'd
> >>(http://www.ocr-research.org.ua/ ) from what I found in an earlier post.
> >>
> >>
> >>>It might sound stupid, sloppy or whatever, but i'm just trying to
> >>>achieve my goal.
> >>>
> >>>Thanks.
> >>>[/color]
> >
> >[/color]
>
> Why? Is this a high security site?
>
> OCR'ing CAPTCHA images does take time and effort - each one is typically
> different. What would be on your site which would require that much effort?
>
> Not to denigrate your site in any form - but the fact is, spammers
> et.al. wouldn't bother with 99.99999% of the CAPTCHA images. They'll
> just go onto another site.
>
> It's like your front door. Your lock isn't unpickable - it just
> requires time and effort on a burglar's part to pick. However, you lock
> your door anyway, because it's a deterrent - the burglar will most
> likely move on (unless you're storing Fort Knox inside).
>
>
> --
> =============== ===
> Remove the "x" from my email address
> Jerry Stuckle
> JDS Computer Training Corp.
> jstucklex@attgl obal.net
> =============== ===[/color]

Well you're probably right, but i also still haven't found a 'good'
CAPTCHA method that doesn't rely on sessions.

I'd like to have two inputs: 1 by the user, and one hidden formfield,
each with their own decryption key, and compare those,
but i haven't found a proper encryption / decryption function yet, that
is good, but quite easy to understand (not to break! ;) )

Frizzle.

**Jim Michaels** · Feb 18 '06, 05:35 AM

Re: An encrypting function.

"frizzle" <phpfrizzle@gma il.com> wrote in message
news:1139313323 .133826.179460@ o13g2000cwo.goo glegroups.com.. .[color=blue]
> Jerry Stuckle wrote:[color=green]
>> frizzle wrote:[color=darkred]
>> > Thanks, indeed that's what i meant.
>> > Apparently it's a weaker system then i imagined.
>> > I guess i'll have to find another alternative again ... :(
>> >
>> > Greetings Frizzle.
>> >
>> >
>> > Jim Michaels wrote:
>> >
>> >>"frizzle" <phpfrizzle@gma il.com> wrote in message
>> >>news:11382271 80.394441.17763 0@z14g2000cwz.g ooglegroups.com ...
>> >>
>> >>>Carl Vondrick wrote:
>> >>>
>> >>>>You may want to look into Mcrypt
>> >>>>(http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
>> >>>>what are you really try to achieve?
>> >>>
>> >>>What i'm trying to do is build a way of security that a human is
>> >>>submitting a form.
>> >>>I know there are ways out there already, but i also have other
>> >>>purposes
>> >>>in mind.
>> >>>
>> >>>Example:
>> >>>
>> >>>Image random generated according to key 1:
>> >>>
>> >>> image.php?txt=k jGKUGFfas8gkjaf Kfasdf
>> >>>
>> >>>The image is a php file, getting $_GET['txt'], decrypt it according
>> >>>key 1, and encrypt it according to key 2. The second encrypting
>> >>>becomes visible in the actual image.
>> >>>
>> >>>I have a have a hidden form field with the value of key 1, and the
>> >>>visitor has to insert the text from the image / key 2 into a form
>> >>>field.
>> >>>
>> >>>Then after posting i compare the decrypted hidden formfield's value
>> >>>against the user submitted value ( / image's value). if they match,
>> >>>the user read the image, and is human ...
>> >>
>> >>Not sure, but sounds like a CAPTCHA. They can be OCR'd
>> >>(http://www.ocr-research.org.ua/ ) from what I found in an earlier
>> >>post.
>> >>
>> >>
>> >>>It might sound stupid, sloppy or whatever, but i'm just trying to
>> >>>achieve my goal.
>> >>>
>> >>>Thanks.
>> >>>
>> >
>> >[/color]
>>
>> Why? Is this a high security site?
>>
>> OCR'ing CAPTCHA images does take time and effort - each one is typically
>> different. What would be on your site which would require that much
>> effort?
>>
>> Not to denigrate your site in any form - but the fact is, spammers
>> et.al. wouldn't bother with 99.99999% of the CAPTCHA images. They'll
>> just go onto another site.
>>
>> It's like your front door. Your lock isn't unpickable - it just
>> requires time and effort on a burglar's part to pick. However, you lock
>> your door anyway, because it's a deterrent - the burglar will most
>> likely move on (unless you're storing Fort Knox inside).
>>
>>
>> --
>> =============== ===
>> Remove the "x" from my email address
>> Jerry Stuckle
>> JDS Computer Training Corp.
>> jstucklex@attgl obal.net
>> =============== ===[/color]
>
> Well you're probably right, but i also still haven't found a 'good'
> CAPTCHA method that doesn't rely on sessions.
>
> I'd like to have two inputs: 1 by the user, and one hidden formfield,
> each with their own decryption key, and compare those,
> but i haven't found a proper encryption / decryption function yet, that
> is good, but quite easy to understand (not to break! ;) )
>
> Frizzle.[/color]

use MD5 digits as an index into a dictionary array, and use soundex to
compare words in case they mistype, using only a subset of the md5 string?
[color=blue]
>[/color]

**Jim Michaels** · Feb 18 '06, 06:35 AM

Re: An encrypting function.

"Jerry Stuckle" <jstucklex@attg lobal.net> wrote in message
news:sqednSzHUN QL43XeRVn-iw@comcast.com. ..[color=blue]
> frizzle wrote:[color=green]
>> Thanks, indeed that's what i meant.
>> Apparently it's a weaker system then i imagined.
>> I guess i'll have to find another alternative again ... :(
>>
>> Greetings Frizzle.
>>
>>
>> Jim Michaels wrote:
>>[color=darkred]
>>>"frizzle" <phpfrizzle@gma il.com> wrote in message
>>>news:1138227 180.394441.1776 30@z14g2000cwz. googlegroups.co m...
>>>
>>>>Carl Vondrick wrote:
>>>>
>>>>>You may want to look into Mcrypt
>>>>>(http://us3.php.net/manual/en/ref.mcrypt.php). But, with Peter said,
>>>>>what are you really try to achieve?
>>>>
>>>>What i'm trying to do is build a way of security that a human is
>>>>submittin g a form.
>>>>I know there are ways out there already, but i also have other purposes
>>>>in mind.
>>>>
>>>>Example:
>>>>
>>>>Image random generated according to key 1:
>>>>
>>>> image.php?txt=k jGKUGFfas8gkjaf Kfasdf
>>>>
>>>>The image is a php file, getting $_GET['txt'], decrypt it according
>>>>key 1, and encrypt it according to key 2. The second encrypting
>>>>becomes visible in the actual image.
>>>>
>>>>I have a have a hidden form field with the value of key 1, and the
>>>>visitor has to insert the text from the image / key 2 into a form
>>>>field.
>>>>
>>>>Then after posting i compare the decrypted hidden formfield's value
>>>>against the user submitted value ( / image's value). if they match,
>>>>the user read the image, and is human ...
>>>
>>>Not sure, but sounds like a CAPTCHA. They can be OCR'd
>>>(http://www.ocr-research.org.ua/ ) from what I found in an earlier post.
>>>
>>>
>>>>It might sound stupid, sloppy or whatever, but i'm just trying to
>>>>achieve my goal.
>>>>
>>>>Thanks.
>>>>[/color]
>>
>>[/color]
>
> Why? Is this a high security site?
>
> OCR'ing CAPTCHA images does take time and effort - each one is typically
> different. What would be on your site which would require that much
> effort?
>
> Not to denigrate your site in any form - but the fact is, spammers et.al.
> wouldn't bother with 99.99999% of the CAPTCHA images. They'll just go
> onto another site.
>
> It's like your front door. Your lock isn't unpickable - it just requires
> time and effort on a burglar's part to pick. However, you lock your door
> anyway, because it's a deterrent - the burglar will most likely move on
> (unless you're storing Fort Knox inside).[/color]

I think he's got a point there. I dunno. here's one. Won't guarantee it.
there's better ones out there that mangle fonts.

WordPress Plugins

http://wp-plugins.net/plugin/captcha/

Choose from thousands of free plugins to build, customize, and enhance your WordPress website.

I've looked through the GD source code. it can't mangle fonts. only rotate
them. for that you're probably looking at making a DLL with the bitstream
library or something like that, or relying on windows' truetype font
rendering engine to render a bitmap, which could possibly do the job.
[color=blue]
>
>
> --
> =============== ===
> Remove the "x" from my email address
> Jerry Stuckle
> JDS Computer Training Corp.
> jstucklex@attgl obal.net
> =============== ===[/color]

An encrypting function.

An encrypting function.

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment