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Node.js

S/MIME Decrypt using Certificate and Private Key in Apple Keychain

See more Apple Keychain Examples

Decrypts S/MIME using a certificate with private key found in the Apple Keychain.

Chilkat Node.js Downloads

Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

    var cert = new chilkat.Cert();

    //  Load the certificate to be used for decryption by the Subject Common Name
    //  On MacOS and iOS, Chilkat will search the Keychain(s) for the matching certificate.
    //  Note: The private key must be present to decrypt.
    success = cert.LoadByCommonName("My Cert");
    if (success == false) {
        console.log(cert.LastErrorText);
        return;
    }

    console.log("Cert has private key: " + cert.HasPrivateKey());

    //  Load the MIME to be decrypted.
    //  We encrypted using this example:  S/MIME Encrypt using Certificate in Apple Keychain
    var mime = new chilkat.Mime();
    success = mime.LoadMimeFile("./encrypted.mime");
    if (success == false) {
        console.log(mime.LastErrorText);
        return;
    }

    console.log(mime.GetMime());
    console.log("----");

    //  Here's the encrypted MIME:

    //  Subject: test
    //  SomeHeader: 123
    //  Content-Type: application/x-pkcs7-mime; name="smime.p7m"; smime-type="enveloped-data"
    //  Content-Disposition: attachment; filename="smime.p7m"
    //  Content-Transfer-Encoding: base64
    //  
    //  MIICSwYJKoZIhvcNAQcDoIICPDCCAjgCAQAxggGzMIIBrwIBADCBljCBgTELMAkGA1UEBhMCSVQx
    //  EDAOBgNVBAgMB0JlcmdhbW8xGTAXBgNVBAcMEFBvbnRlIFNhbiBQaWV0cm8xFzAVBgNVBAoMDkFj
    //  dGFsaXMgUy5wLkEuMSwwKgYDVQQDDCNBY3RhbGlzIENsaWVudCBBdXRoZW50aWNhdGlvbiBDQSBH
    //  MwIQPCWvkSv8oQ7xRmEHJ6TzEDANBgkqhkiG9w0BAQEFAASCAQB3VZvHRE5EWxug7Sckpcz1ucDZ
    //  YiTKiqmyPt75MhzNRQLtKFx/jWwlemUwnPMzeu6yutCkZ74Bdn7MBsfDqV3bUz43wAu+fRBteGvF
    //  mTc00MfY8L7o8dkpj4AqAOCj4hKQzbSE99GvSzyXcPE2Gm5NrOPtKxqfFqbBRTCb4fBZP84LaL+x
    //  rnYfrM4qXTppixyN8iFYCd4maEbMu/GA5o+j0BkDDnx42pILDoAGV/ERyx55Y3Nc2Mhm/cITBMNn
    //  g7uS9KPrlYizNaqVu09Hi9jg4gdZaRiTjUqg05tSOk/YqIQxTgfscwSPY92/ewpI6e1EHtLt8Q33
    //  gWCbERptSntUMHwGCSqGSIb3DQEHATAdBglghkgBZQMEAQIEENm1AxeXlEMx7p6McjHIj5CAUEQj
    //  0GuJ5LnTqiqIjOiwmwNidl1N1TRluxX5vAQvwBuYE6bQK4+i04yn2Av3cucW4kvxgP2Nmni+XgQt
    //  aPPKlasaVceEeZ15IYjw77/m3YYn

    //  -------------------------------------
    //  Decrypt the MIME.
    success = mime.DecryptUsingCert(cert);
    if (success == false) {
        console.log(mime.LastErrorText);
        return;
    }

    //  -------------------------------------
    //  Note: A password dialog may be shown, possibly twice, when accessing the private key.
    //  See the following blog post explaining how to suppress the dialog:
    //  Suppress Password Dialog when Accessing Private Key in Apple Keychain

    //  Show the unencrypted MIME
    console.log(mime.GetMime());

    //  Here's the decrypted MIME

    //  Subject: test
    //  SomeHeader: 123
    //  Content-Type: text/plain
    //  
    //  This is the body.

}

chilkatExample();