Reg: DES Decryption in IBMi

Hi Everyone,

Currently I have a scenario like Java will encrypt an image using
DES/CBC/PKCS5Padding with an 8 character length Key and IV they were using
in an array of data like IVBytesJpg = new byte[]{44, 140, (byte)146, 35,
26,(byte) 149, (byte)136, 150 } and store the encrypted image into an
Windows Share Drive (/WindosIP/Shared Drive/Image File).

I am accessing the Windows share drive from iSeries and decrypting the
image and exposing the image in base64 format in REST API.

To achieve this I am using the below steps

Step 1: Fetch the encrypted image from Windows Share drive using the below
code in rpgle (using QNTC)

dcl-s Wrk_WindowsImage sqltype(clob_file);
dcl-s Wrk_Image sqltype(clob:500000);

Wrk_WindowsImage_FO = SQFRD;
Wrk_WindowsImage_Name = /QNTC/WindosIP/Shared Drive/Image File
Wrk_WindowsImage_NL = %len(%trimr(Wrk_WindowsImage_Name));
exec sql values :Wrk_WindowsImage into :Wrk_Image;

This way I can fetch the encrypted image from Windows Share drive into an
CLOB variable

Step 2: Decrypt the Image

Using the IBMi API Qc3DecryptData and Algorithm Format as ALGD0200 and Key
Format as KEYD0200

In the algorithm ALGD0200, I am not sure how to use PKCS5Padding, So I am
just using the Pad option QC3PO as '0' (Do not remove padding).

I am not sure how can I use the array of data (IVBytesJpg = new byte[]{44,
140, (byte)146, 35, 26,(byte) 149, (byte)136, 150 }) as input for IV, if
someone shed some light it would be great.

Step 3: Convert the image into Base64 format
Convert the decrypted value in Base64 format. For this I am planning to use
Scott Klements Base64 utility (https://www.scottklement.com/base64/)

Could you please help me out in how to use the PKCS5Padding and array of
data as IV in Qc3DecryptData API?

Regards,
Suren