(PHP Extension) Validate a .pkpass Archive

Opens a .pkpass archive (which is just a .zip renamed to .pkpass) and validates the contents. The hashes in the manifest are compared with the computed hash values for each individual file. If all computed hash values match, then the signature is verified.

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.

$crypt = new CkCrypt2();
$zip = new CkZip();

$success = $zip->OpenZip('qa_data/pkpass/invalid.pkpass');
if ($success == false) {
    print $zip->lastErrorText() . "\n";
    exit;
}

// Get the contents of the manifest.json file, which contains something like this:

// {
//   "icon.png" : "0296b01347b3173e98438a003b0e88986340b2d8",
//   "logo.png" : "25de09e2d3b01ce1fe00c2ca9a90a2be1aaa05cf",
//   "icon@2x.png" : "5afd9585b08c65fdf105a90c8bd643407cba2787",
//   "pass.json" : "145ea5a5db784fff485126c77ecf7a1fc2a88ee7",
//   "strip@2x.png" : "468fa7bc93e6b55342b56fda09bdce7c829d7d46",
//   "strip.png" : "736d01f84cb73d06e8a9932e43076d68f19461ff"
// }

// ent is a CkZipEntry
$ent = $zip->GetEntryByName('manifest.json');
if ($zip->get_LastMethodSuccess() == false) {
    print 'manifest.json entry not found.' . "\n";
    exit;
}

// Get the exact content of the manifest.json for later signature verification.
$bdManifest = new CkBinData();
$success = $ent->UnzipToBd($bdManifest);

$json = new CkJsonObject();
$json->put_EmitCompact(false);
$json->Load($ent->unzipToString(0,'utf-8'));
print $json->emit() . "\n";

// For each file in the JSON, get the filename and hex hash value.
$crypt->put_EncodingMode('hexlower');
$crypt->put_HashAlgorithm('sha1');

$someHashesFailed = false;

$sbHashHex = new CkStringBuilder();
$bdFileData = new CkBinData();
$numMembers = $json->get_Size();
$i = 0;
while ($i < $numMembers) {
    $filename = $json->nameAt($i);
    $sbHashHex->Clear();
    $sbHashHex->Append($json->stringAt($i));

    // ent is a CkZipEntry
    $ent = $zip->GetEntryByName($filename);
    if ($zip->get_LastMethodSuccess() == false) {
        print $filename . ' not found in the pkpass file.' . "\n";
        exit;
    }

    // Get the data for this file.
    $bdFileData->Clear();
    $success = $ent->UnzipToBd($bdFileData);

    $computedHashHex = $crypt->hashBdENC($bdFileData);
    if ($sbHashHex->ContentsEqual($computedHashHex,false) == false) {
        print 'Computed hash does not match stored hash for ' . $filename . "\n";
        print '  computed: ' . $computedHashHex . "\n";
        print '  stored:   ' . $sbHashHex->getAsString() . "\n";
        $someHashesFailed = true;
    }
    else {
        print 'hash verified for ' . $filename . '(' . $computedHashHex . ')' . "\n";
    }

    $i = $i + 1;
}

if ($someHashesFailed == true) {
    print 'Some hashes failed.' . "\n";
    exit;
}

// Let's verify the signature..
// First get the signature.
// ent is a CkZipEntry
$ent = $zip->GetEntryByName('signature');
if ($zip->get_LastMethodSuccess() == false) {
    print 'signature not found in the pkpass file.' . "\n";
    exit;
}

$bdSignature = new CkBinData();
$success = $ent->UnzipToBd($bdSignature);

// Show the contents of the signature in base64 encoding.
print 'Signature:' . "\n";
print $bdSignature->getEncoded('base64_mime') . "\n";
print '----' . "\n";

// Verify the signature against the manifest.json
$crypt->put_EncodingMode('base64');
$verified = $crypt->VerifyBdENC($bdManifest,$bdSignature->getEncoded('base64'));
if ($verified == false) {
    print $crypt->lastErrorText() . "\n";
}

print 'signature verified = ' . $verified . "\n";

?>