Sign with .pfx to create .p7s, Verify with .cer

Perl example to sign a file using a .pfx and creating a .p7s file as output. It then uses a .cer file to verify the signature.

Download Chilkat Perl Module

use chilkat;

$crypt = new chilkat::CkCrypt2();

#  Any string argument automatically begins the 30-day trial.
$success = $crypt->UnlockComponent("30-day trial");
if ($success != 1) {
    print "Crypt component unlock failed" . "\n";
    exit;
}

$certStore = new chilkat::CkCertStore();
$success = $certStore->LoadPfxFile("chilkat.pfx","myPfxPassword");
if ($success != 1) {
    print $certStore->lastErrorText() . "\n";
    exit;
}

$cert = $certStore->FindCertBySubjectCN("Chilkat Software, Inc.");
if ($cert eq null ) {
    print "Failed to find certificate" . "\n";
    exit;
}

#  We can explicitly choose hash/encryption algorithms using a CSP.
$csp = new chilkat::CkCSP();
$csp->SetProviderMicrosoftEnhanced();
$csp->SetHashAlgorithm("sha-1");

#  Tell the crypt component to use this cert and this CSP.
$crypt->SetSigningCert($cert);
$crypt->SetCSP($csp);

#  We can sign any type of file, creating a .p7s as output:
$success = $crypt->CreateP7S("hamlet.xml","hamlet.p7s");
if ($success == 1) {
    print "Signature created." . "\n";
}
else {
    print $crypt->lastErrorText() . "\n";
}

#  Verify and restore the original file:
#  Use a cert from a .cer file (which only contains the public key)
$cert2 = new chilkat::CkCert();
$success = $cert2->LoadFromFile("chilkat.cer");
if ($success != 1) {
    print $cert2->lastErrorText() . "\n";
    exit;
}

$crypt->SetVerifyCert($cert2);

$success = $crypt->VerifyP7S("hamlet.xml","hamlet.p7s");
if ($success == 1) {
    print "Signature verified." . "\n";
}
else {
    print $crypt->lastErrorText() . "\n";
}