(Node.js) Sign JSON (or any Text) to Create a Detached PKCS7 Signature

Demonstrates how to sign JSON or any string using a certificate + private key from a .p12/.pfx to create a detached PKCS7 signature. (A detached signature is one that does not embed the original signed data.)

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var crypt = new chilkat.Crypt2();

    var cert = new chilkat.Cert();
    var success = cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123");
    if (success !== true) {
        console.log(cert.LastErrorText);
        return;
    }

    // Tell the crypt component to use this cert.
    success = crypt.SetSigningCert(cert);
    if (success !== true) {
        console.log(crypt.LastErrorText);
        return;
    }

    crypt.HashAlgorithm = "sha256";

    // By default, all the certs in the chain of authentication are included in the signature.
    // If desired, we can choose to only include the signing certificate:
    crypt.IncludeCertChain = false;

    // Create the detached signature, which does NOT contain the original data.
    // To create a PKCS7 signature that contains the original data, see CAdES Sign JSON
    crypt.Charset = "utf-8";

    var stringToSign = "{ \"abc\": 123}";
    detachedSig = crypt.SignString(stringToSign);
    if (crypt.LastMethodSuccess == false) {
        console.log(crypt.LastErrorText);
        return;
    }

    // Verify the signature against the original data.
    var verified = crypt.VerifyString(stringToSign,detachedSig);
    if (verified == false) {
        console.log(crypt.LastErrorText);
        return;
    }

    console.log("Success!");

}

chilkatExample();