(PHP Extension) Swift Alliance LAU XML Signature

Calculating the LAU for Swift Alliance File Act XML using HMAC SHA256. (The XML signature, also referred to as Local Authentication (LAU), is computed using the algorithm HMAC based on SHA-256.)

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

// We begin with the following XML:

// <?xml version="1.0" encoding="UTF-8"?>
// <Saa:DataPDU xmlns:Saa="urn:swift:saa:xsd:saa.2.0" xmlns:Sw="urn:swift:snl:ns.Sw" xmlns:SwInt="urn:swift:snl:ns.SwInt" xmlns:SwGbl="urn:swift:snl:ns.SwGbl" xmlns:SwSec="urn:swift:snl:ns.SwSec">
//     <Saa:Revision>2.0.6</Saa:Revision>
//     <Saa:Header>
//         <Saa:Message>
//             <Saa:SenderReference>Ref760FA1234</Saa:SenderReference>
//             <Saa:MessageIdentifier>tsrv.fin.mt7xx.gteesstandbys</Saa:MessageIdentifier>
//             <Saa:Format>File</Saa:Format>
//             <Saa:SubFormat>Input</Saa:SubFormat>
//             <Saa:Sender>
//                 <Saa:DN>cn=su8,o=ptsqgbbb,o=swift</Saa:DN>
//                 <Saa:FullName>
//                     <Saa:X1>PTSQGBBBXXX</Saa:X1>
//                 </Saa:FullName>
//             </Saa:Sender>
//             <Saa:Receiver>
//                 <Saa:DN>cn=abc,ou=saa,o=xxx,o=swift</Saa:DN>
//                 <Saa:FullName>
//                     <Saa:X1>PTSXXXXXXXX</Saa:X1>
//                     <Saa:X2>saa</Saa:X2>
//                 </Saa:FullName>
//             </Saa:Receiver>
//             <Saa:InterfaceInfo>
//                 <Saa:UserReference>CRE...</Saa:UserReference>
//                 <Saa:MessageCreator>ApplicationInterface</Saa:MessageCreator>
//                 <Saa:MessageContext>Original</Saa:MessageContext>
//                 <Saa:MessageNature>Financial</Saa:MessageNature>
//             </Saa:InterfaceInfo>
//             <Saa:NetworkInfo>
//                 <Saa:Priority>Normal</Saa:Priority>
//                 <Saa:IsPossibleDuplicate>true</Saa:IsPossibleDuplicate>
//                 <Saa:Service>swift.corp.fast!x</Saa:Service>
//                 <Saa:Network>Application</Saa:Network>
//                 <Saa:SessionNr>0080</Saa:SessionNr>
//                 <Saa:SeqNr>000001</Saa:SeqNr>
//                 <Saa:SWIFTNetNetworkInfo>
//                     <Saa:RequestType>tsrv.fin.mt7xx.gteesstandbys</Saa:RequestType>
//                     <Saa:Reference>2f949999-d32e-49eb-9999-9a819b9b9c0d</Saa:Reference>
//                     <Saa:FileInfo>SwCompression=Zip</Saa:FileInfo>
//                 </Saa:SWIFTNetNetworkInfo>
//             </Saa:NetworkInfo>
//             <Saa:SecurityInfo>
//                 <Saa:SWIFTNetSecurityInfo>
//                     <Saa:FileDigestAlgorithm>SHA-256</Saa:FileDigestAlgorithm>
//                     <Saa:FileDigestValue>9tnnjIgsowPSU+ehm8Rb0J5TvZIvhCYnySzFkpur1aw=</Saa:FileDigestValue>
//                 </Saa:SWIFTNetSecurityInfo>
//             </Saa:SecurityInfo>
//             <Saa:FileLogicalName>Payload.ZIP</Saa:FileLogicalName>
//             <Saa:ExpiryDateTime>20210712074808</Saa:ExpiryDateTime>
//         </Saa:Message>
//     </Saa:Header>
//     <Saa:Body>Payload.ZIP</Saa:Body>
// </Saa:DataPDU>

// Load the XML file to be signed.
$sbXml = new CkStringBuilder();
$success = $sbXml->LoadFile('c:/someDir/fileToSign.xml','utf-8');
if ($success == false) {
    print 'Failed to load XML file.' . "\n";
    exit;
}

// We need to add a "LAU" XML element just before the "</Saa:DataPDU>"
$numReplaced = $sbXml->Replace('</Saa:DataPDU>','<LAU xmlns=\'urn:swift:saa:xsd:saa.2.0\'></LAU></Saa:DataPDU>');

$gen = new CkXmlDSigGen();
$gen->put_SigLocation('Saa:DataPDU|LAU');
$gen->put_SigLocationMod(0);
$gen->put_SigNamespacePrefix('ds');
$gen->put_SigNamespaceUri('http://www.w3.org/2000/09/xmldsig#');
$gen->put_SignedInfoCanonAlg('EXCL_C14N');
$gen->put_SignedInfoDigestMethod('sha256');
$gen->put_Behaviors('CompactSignedXml');

// Sign the entire document.
$gen->AddSameDocRef('','sha256','EXCL_C14N','','');

// Set our HMAC key
$gen->SetHmacKey('Abcdef0123456789Abcdef0123456789','ascii');

// Sign the XML:
$success = $gen->CreateXmlDSigSb($sbXml);
if ($success == false) {
    print $gen->lastErrorText() . "\n";
    exit;
}

// Examine the signed XML
print $sbXml->getAsString() . "\n";

// Save the signed XML to a file.
$success = $sbXml->WriteFile('c:/someDir/signedFile.xml','utf-8',false);

?>