(Ruby) Create a Hash Signature for Value Added Tax Audit SOAP Message for Angola

Demonstrates how to create a hash signature that is required in Value Added Tax Audit Files in Angola, Africa.

It is the following two instructions that should be used to create a hash value to be put into a <hash></hash> field in SOAP XML file containing the tax data for the VAT authorities:

openssl dgst -shal -sign private.pem -outRegisto1.shal Registo1.txt

then

openssl enc -base64 - in Registo1.shal -out Registo1.b64 -A

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

pkey = Chilkat::CkPrivateKey.new()

# Load the private key from an PEM file.
# Provide the password in the 2nd argument.
# If no password is needed, just pass an empty string.
success = pkey.LoadAnyFormatFile("qa_data/rsa/rsaPrivKey_secret.pem","secret")
if (success != true)
    print pkey.lastErrorText() + "\n";
    exit
end

# Assuming this is an RSA private key..
rsa = Chilkat::CkRsa.new()

# Import the private key into the RSA object:
success = rsa.ImportPrivateKeyObj(pkey)
if (success != true)
    print rsa.lastErrorText() + "\n";
    exit
end

# OpenSSL uses big-endian.
rsa.put_LittleEndian(false)

# SHA1 hash and sign, and return base64.
rsa.put_EncodingMode("base64")
b64sig = rsa.signStringENC("2018-05-18,2018-05-18T11:22:19;FAC 001/18;53.00;","sha1")
print b64sig + "\n";

# The signature is equal in size to your private key.  For example, if you have a 1024-bit RSA key,
# then 1024 bits = 128 bytes.   When 128 bytes is base64 encoded, the result is a string approximately
# 4/3rds the size of the original.  128 * 4 / 3 = (approximately) 172 bytes.

# If your RSA key is 2048-bits, then your signature will be twice as long.