Re: Reg: HMAC Calculation

[mlazarus <mlazarus@xxxxxxxxxxxx>]

Suren,

 How is headerPayload defined?  If it's a variying field you'll likely 
need to change the line in the call to:

%addr(headerPayload: *DATA)


 -mark

On 12/7/2020 4:14 AM, Suren K wrote:
> 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
>