CVC generating

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kapilashantha rajapaksha

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Dec 7, 2009, 3:04:48 AM12/7/09
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Dear Sir,

I'm having with problem while generating CVC value for credit card. Can any  body tell me how to  form  input data using PAN,Expired data and service code (in RG7000)?


We have correct CVK A/B pair

Example

PAN =5341 7800 0000 1002
Expire data = 1111
Service code =201

I want to know how to form input data block using these value ?

Regards
-Kapila

Mark Salter

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Dec 7, 2009, 3:29:07 AM12/7/09
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kapilashantha rajapaksha wrote:
> I'm having with problem while generating CVC value for credit card. Can any
> body tell me how to form input data using PAN,Expired data and service
> code (in RG7000)?

What is the 'problem'?
Is the wrong value being generated, an error message being issued, a
return indicating a problem or something else?

>
> We have correct CVK A/B pair
Care to share the clear *test* value, so we may generate the CVC for
comparison?

>
> Example
>
> PAN =5341 7800 0000 1002
> Expire data = 1111
> Service code =201
>
> I want to know how to form input data block using these value ?
Have you read your HSM manual(s)? I'm sure it will define the data it
expects to be passed and how for each supported function?

In pseudo code, the CVC/CVV algorithm takes :-

(pan+expireData+ServiceCode+"00000000000000000000000000000000").substring(0,32)

but the message passed to your HSM might want the component parts
separately or unpadded?


--
Mark

kapilashantha rajapaksha

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Dec 7, 2009, 3:48:37 AM12/7/09
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Thanks Mark,

This is the way for getting success result
Thanks a lot
(pan+expireData+ServiceCode+"00000000000000000000000000000000").substring(0,32)


Regards
Kapila




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Sandile

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Oct 24, 2018, 1:52:40 PM10/24/18
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Please tell to find CVKA/B

Sandile

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Oct 24, 2018, 2:32:11 PM10/24/18
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Hi,
Mark please help to find CVK A/B

Kapilashantha Rajapaksha

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Oct 25, 2018, 2:41:22 AM10/25/18
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Tell your exact requirement because it's not clear for me

On Wed, Oct 24, 2018, 11:22 PM Sandile <nts...@gmail.com> wrote:
Please tell to find CVKA/B

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Sandile Mkhize

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Oct 25, 2018, 3:23:24 AM10/25/18
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Hi kapilashantha 
I want to calculate iccv but I don't know how to find CVK A/B of the particular card, the only think I have is (service code, expired date and pan number) please help me, basically I want to write a chip... thanks

Regards
Sandile.

Kapilashantha Rajapaksha

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Oct 25, 2018, 4:51:29 AM10/25/18
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Ok,

CVK -A and CVK -B are  single length DES keys which is not stored in cards / chips. And further it's used for issuing  group of cards. it  means not related to particular card. 

These keys are stored in database / host in encrypted form.   In the process of CVV/iCVV  generation, we have to call HSM functions  with encrypted CVK-A and CVK-B with your other data. So it will be only decrypting inside of HSM.

But if you want to get clear CVK A-B , you may ask from bank or authorized office who has entered CVK keys into HSM. Otherwise you can't find these keys from anywhere.

Regards,
  

Sandile Mkhize

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Oct 25, 2018, 5:11:51 AM10/25/18
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Hi

So you mean I can't calculate iCVV number , becouse of not having CVKA/B. Or is there other way of calculating iCVV number without having CVKA/B .
Do you know any alternative way of finding iCVV number.

Regards
Sandile

Kapilashantha Rajapaksha

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Oct 25, 2018, 5:22:18 AM10/25/18
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You can't generate without CVKA/B.  But let me know purpose of generating icvv in yourself?

Sandile Mkhize

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Oct 25, 2018, 6:35:18 AM10/25/18
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Hi 

The purpose is to change ccv to iccv , basically I have track 2 for magnactic stripe and I want to convert it into chip/emv track 2, so the different between these two track 2 is cvv number that is why I want to calculate iccv from ccv.because there is a tool that am using which is eftlab but they are so much keys I don't know .

Kapilashantha Rajapaksha

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Oct 25, 2018, 6:59:40 AM10/25/18
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I hope that you are doing card migration from magnetic strip to EMV right ?.   Yes CVV  is in track-2.  However to translate cvv to  icvv you should follow same HSM or you have to export CVK A-B and import to your tool.

In addition, you may look into MDK (Master Derivation Key )  to validate and generate  ARQC and ARPC for EMV cards.

Regards  

Sandile Mkhize

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Oct 25, 2018, 7:10:49 AM10/25/18
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Yes am doing card migration from magnetic to EMV,Where can I get HSM and how to export CVKA/B. that what I want ,to import CVKA-B into my tool.

Yes I also want that to calculate ARQC and ARPC for emv card. I will screen grab it for you to see what am talking about.there is some key that are not provided when calculating ARQC 
.

Kapilashantha Rajapaksha

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Oct 25, 2018, 7:26:32 AM10/25/18
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It's all in HSM manual (How to export and import ).  Let me know the HSM type they are currently using ?

Sandile Mkhize

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Oct 25, 2018, 7:33:09 AM10/25/18
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      They are using  Hsm    thlales
 Am not sure if is what you want.but it eftlab the tool am using.

Mohammad nasiri

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Mar 25, 2019, 7:12:03 PM3/25/19
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hi
please help me
im PVV
PVK
How can i get؟؟؟؟

Track 2 Magnetic tape I write!

need to Offset/Pvv

Jason

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Jun 7, 2020, 4:16:27 PM6/7/20
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Hello sandile! Any luck finding cvk a/b?

Jason

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Jun 7, 2020, 4:16:27 PM6/7/20
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Hello, is thier any way how to find cvk a/b without HSM.... I know the pan, expiring date, CVV and CVC as well. But at least I need to know how cvk a/b is created. Thank you

Alejandro Revilla

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Jun 7, 2020, 4:17:21 PM6/7/20
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Sure, you need to contact the key custodians and ask them for the clear text key parts of that CVK.



On Sun, Jun 7, 2020 at 5:16 PM Jason <sopho...@gmail.com> wrote:
Hello, is thier any way how to find cvk a/b without HSM.... I know the pan, expiring date, CVV and CVC as well. But at least I need to know how cvk a/b is created. Thank you

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