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JavaScript

Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

See more OpenSSL Examples

Demonstrates how to decrypt binary DER that was encrypted using the following openssl command:
openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt
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.

// Duplicates the following openssl command:
// openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

var cert = new CkCert();
success = cert.LoadFromFile("qa_data/openssl/EE.cer");
if (success == false) {
    console.log(cert.LastErrorText);
    return;
}

var bd = new CkBinData();
success = bd.LoadFile("qa_data/openssl/EE.key");
// Assuming success..

var privKey = new CkPrivateKey();
success = privKey.LoadAnyFormat(bd,"");
if (success == false) {
    console.log(privKey.LastErrorText);
    return;
}

var crypt = new CkCrypt2();
success = crypt.SetDecryptCert2(cert,privKey);
if (success == false) {
    console.log(crypt.LastErrorText);
    return;
}

crypt.CryptAlgorithm = "PKI";
success = crypt.CkDecryptFile("qa_data/openssl/hello.txt.enc","qa_output/hello.txt");
if (success == false) {
    console.log(crypt.LastErrorText);
    return;
}

console.log("Success.");