Simple encryption function in Dart language

Job ID: 33034442

Budget: $10 – $30 USD

Hey
I would like from you to help me create a hash function, the steps are pretty simple:

T = they all have tags (1 to 5)
L = and lengths (e.g. name="test", hence its length is 4
V = 5 values (name, taxID, date, total, totalVat)



1. for each value, hash T and L to hex, then to string
2. concatenate the hashed T and L with V

e.g. for name, since its tag is 1 and its length is 4 ( "test" ) then tag's hash is 01, and the length's tag is 04, so concatenating them with the value: 0104test

and we do that for each value, let's take another example for taxID

its tag is 2, and length is 10 (constant length) and its value 1234567891

tag's hex is 02, length is 0a, hence the TLV is 020a1234567891


GUYS
here's the exact docs:
https://blogs.sap.com/2021/11/18/qr-code-in-base64-encoding-for-ksa-e-invoicing/
https://salla.dev/blog/qr-code-fatoora-e-invoicing-zatca/
I might be wrong in my explanation, so please head back to the docs it'll be explaind better.


I need this ASAP with the best offer from the most experienced, Thanks.
Related categories: Cryptography Dart Flutter Encryption