(Perl) Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

1. Creates a SHA256 digest of the contents of the input file
2. Signs the SHA256 digest using the private key.

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:
$success = $pkey->LoadPemFile("private.pem");
if ($success != 1) {
    print $pkey->lastErrorText() . "\r\n";
    exit;
}

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

# Import the private key into the RSA component:
$success = $rsa->ImportPrivateKeyObj($pkey);
if ($success != 1) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

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

# Load the file to be signed.
$bdFileData = chilkat::CkBinData->new();
$success = $bdFileData->LoadFile("in.dat");

$bdSig = chilkat::CkBinData->new();
$success = $rsa->SignBd($bdFileData,"sha256",$bdSig);
if ($success != 1) {
    print $rsa->lastErrorText() . "\r\n";
    exit;
}

# Save the binary signature to a file.
$success = $bdSig->WriteFile("signature.sig");
if ($success != 1) {
    print "Failed to write signature.sig." . "\r\n";
    exit;
}

print "Success." . "\r\n";