Re: HMAC Calculation

[Suren K <suren7437@xxxxxxxxx>]

Hi Thomas,

I tried that as well but i am not getting the expected result.

I declared a field with CCSID as UTF-8

dcl-s signKey char(100) ccsid(*utf8);

For now I hardcoded the secret key in plain text inside the program and
used the Signkey field to move the value into the Key data structure.

Regards,
Suren


On Mon, Dec 7, 2020, 5:47 PM Thomas Raddatz <thomas.raddatz@xxxxxx> wrote:

> Did you convert the secret key (KEYD0200) to the ccsid of the target
> system? I assume that you need the hmac for a PC and not for an IBM I,
> right? Therefore you want to use an Ascii or UTF-8 key instead of an EBCDIC
> key, I assume.
>
> In that case the key must be converted to the CCSID of the target system,
> before passing it to the Qc3CalculateHMAC() API.
>
> Thomas.
>
> -----Ursprüngliche Nachricht-----
> Von: RPG400-L <rpg400-l-bounces@xxxxxxxxxxxxxxxxxx> Im Auftrag von Suren K
> Gesendet: Montag, 7. Dezember 2020 10:15
> An: RPG programming on IBM i <rpg400-l@xxxxxxxxxxxxxxxxxx>
> Betreff: Reg: HMAC Calculation
>
> Hi All,
>
> How are you?
>
> I am facing the following issue with Qc3CalculateHMAC API.
>
> Currently i am trying to do the JWT token validation in iSeries, to do
> that i am planning to generate the HMAC using the header, payload and
> signed secret key.
>
> The logic i am using is Passing the input data as
> Header(Base64encoded).Payload(Base64encoded).
>
> 1) For Base64 decoding - SYSTOOLS.BASE64ENCODE function is used.
> 2) Algorithm - SHA256.
> 3) I am passing the Secret Key as plain character text using "KEYD0200"
>
> But the HMAC generated by the API is not correct. Am i doing anything
> wrong?
>
> Qc3CalculateHMAC(
>     %addr(headerPayload) :
>     %len(%trimr(headerPayload)) :
>     'DATA0100' :
>     algd0500 :
>     'ALGD0500' :
>     keyparam :
>     'KEYD0200' :
>     '0' : // crypto
>     *blank : // crypto dev
>     hash :
>     QUSEC);
>
> Could anyone please help me to figure out the issue?
>
> Regards,
> Suren K
> --
> This is the RPG programming on IBM i (RPG400-L) mailing list To post a
> message email: RPG400-L@xxxxxxxxxxxxxxxxxx To subscribe, unsubscribe, or
> change list options,
> visit:
> https://smex12-5-en-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2flists.midrange.com%2fmailman%2flistinfo%2frpg400%2dl&umid=610e4461-c6f6-4a7e-b039-66c99e2689e4&auth=e97acd68c6deb7b858f463424a55c9ae42d5359e-b35601ec44c876b516ef29c843b5d6cb9c44d158
> or email: RPG400-L-request@xxxxxxxxxxxxxxxxxx
> Before posting, please take a moment to review the archives at
> https://smex12-5-en-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2farchive.midrange.com%2frpg400%2dl&umid=610e4461-c6f6-4a7e-b039-66c99e2689e4&auth=e97acd68c6deb7b858f463424a55c9ae42d5359e-b01fb74cc3366396f8ce552b3fb7a7e1d77d948b
> .
>
> Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
> questions.
>
> Help support midrange.com by shopping at amazon.com with our affiliate
> link:
> https://smex12-5-en-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2famazon.midrange.com&umid=610e4461-c6f6-4a7e-b039-66c99e2689e4&auth=e97acd68c6deb7b858f463424a55c9ae42d5359e-25c69241f01dab5b20ef507ba6ee621ff83bc9a0
> --
> This is the RPG programming on IBM i (RPG400-L) mailing list
> To post a message email: RPG400-L@xxxxxxxxxxxxxxxxxx
> To subscribe, unsubscribe, or change list options,
> visit: https://lists.midrange.com/mailman/listinfo/rpg400-l
> or email: RPG400-L-request@xxxxxxxxxxxxxxxxxx
> Before posting, please take a moment to review the archives
> at https://archive.midrange.com/rpg400-l.
>
> Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
> questions.
>
> Help support midrange.com by shopping at amazon.com with our affiliate
> link: https://amazon.midrange.com