(Perl) 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 Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use 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 != 1) {
    print $pkey->lastErrorText() . "\r\n";
    exit;
}

# 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 != 1) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# OpenSSL uses big-endian.
$rsa->put_LittleEndian(0);

# 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 . "\r\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.