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JavaScript

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

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:
openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat
The in.dat file can contain text or binary data of any type. The OpenSSL command does the following:
  1. Creates a SHA256 digest of the contents of the input file
  2. Signs the SHA256 digest using the private key.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

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

var pkey = new CkPrivateKey();

// Load the private key from an PEM file:
success = pkey.LoadPemFile("private.pem");
if (success == false) {
    console.log(pkey.LastErrorText);
    return;
}

var rsa = new CkRsa();

// Import the private key into the RSA component:
success = rsa.UsePrivateKey(pkey);
if (success == false) {
    console.log(rsa.LastErrorText);
    return;
}

// OpenSSL uses big-endian.
rsa.LittleEndian = false;

// Load the file to be signed.
var bdFileData = new CkBinData();
success = bdFileData.LoadFile("in.dat");

var bdSig = new CkBinData();
success = rsa.SignBd(bdFileData,"sha256",bdSig);
if (success == false) {
    console.log(rsa.LastErrorText);
    return;
}

// Save the binary signature to a file.
success = bdSig.WriteFile("signature.sig");
if (success !== true) {
    console.log("Failed to write signature.sig.");
    return;
}

console.log("Success.");