(Perl) SII Chile - FRMT Signature Computation and Add to XML

Compute the FRMT signature and add to the XML. This is the RSA signature of the SHA-1 digest of the "flattened" DD element.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

# Also see:  Compute the FRMA Signature and Add to XML

$xml = chilkat::CkXml->new();

# Load the unsigned XML that contains the following:

# <DTE version="1.0">
#   <Documento ID="F60T33">
#         <TED version="1.0">
#             <DD>
# 		...
#                 <CAF version="1.0">
#                     <DA>
# 			...
#                     </DA>
#                     <FRMA algoritmo="SHA1withRSA">...</FRMA>
#                 </CAF>
#                 ...
#             </DD>
#             ... The FRMT will be added here in another example ...
#         </TED>
#   </Documento>
# </DTE>

$success = $xml->LoadXmlFile("qa_data/xml_dsig/sii_cl/test_1.xml");
if ($success == 0) {
    print "Failed to load initial XML file." . "\r\n";
    exit;
}

# Get a reference to the "DD" element
# ddXml is a Xml
$ddXml = $xml->FindChild("Documento|TED|DD");
if ($xml->get_LastMethodSuccess() == 0) {
    print "Failed to find DD element" . "\r\n";
    exit;
}

#  We need to get the "flattened" DD XML where:
#    - No whitespace between elements.
#    - The 5 pre-defined entities are converted.
#    - The text is encoded in the ISO-8859-1 character set (Latin-1), 
$sbFlattened = chilkat::CkStringBuilder->new();
$ddXml->put_EmitCompact(1);
$ddXml->put_EmitXmlDecl(0);
$ddXml->GetXmlSb($sbFlattened);

# Compute the SHA-1 message digest of the iso-8859-1 byte representation, 
# and sign it with our RSA private key, getting the result in base64 format.

$privKey = chilkat::CkPrivateKey->new();
$success = $privKey->LoadAnyFormatFile("qa_data/rsa/rsaPrivKey_pkcs8.pem","");
if ($success == 0) {
    print $privKey->lastErrorText() . "\r\n";
    exit;
}

$rsa = chilkat::CkRsa->new();
$rsa->ImportPrivateKeyObj($privKey);

$rsa->put_EncodingMode("base64");
$rsa->put_Charset("iso-8859-1");
$sig = $rsa->signStringENC($sbFlattened->getAsString(),"sha1");

# Add the FRMT signature element to the XML.
$xml->UpdateChildContent("Documento|TED|FRMT",$sig);
$xml->UpdateAttrAt("Documento|TED|FRMT",1,"algoritmo","SHA1withRSA");

# See what we have:
$xml->put_EmitCompact(0);
$xml->put_EmitXmlDecl(1);
print $xml->getXml() . "\r\n";