Rust

Convert Java KeyStore to PKCS12 / PFX

See more Java KeyStore (JKS) Examples

Loads a Java keystore file and saves it as a PKCS12 / PFX. A Java keystore (JKS) can contain two types of entries: (1) trusted root certificates or (2) private keys + cert chains. Usually a JKS will contain all entries of one type or another (and thus a particular JKS serves one purpose or another; meaning that a JKS containing trusted roots is used as a source for verifying pre-trusted roots, and a JKS containing private keys (and cert chains) is used as a secure, encrypted store for private keys).

A PKCS12 / PFX typically contains one or more private keys, along with each private key's certificate chain. Therefore, it typically makes sense to only write the private key entries to a PKCS12 (and the associated certificate chains). If a JKS contains trusted root certificates, it makes more sense to conver it to a PEM file (such as the CA cert bundle in PEM format from mozilla.org).

Rust

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

let jks = chilkat::JavaKeyStore::new();

let jks_password = "myJksPassword".to_string();

// Load the Java keystore from a file.  The JKS file password is used
// to verify the keyed digest that is found at the very end of the keystore.
// It verifies that the keystore has not been modified.
if jks.load_file(&jks_password, "/someDir/keyStore.jks").is_err() {
    println!("{}", jks.last_error_text());
    return;
}

// To convert, we'll access the private key entries
// from the JKS, add each to the PKCS12, and then save the PKCS12.
let pkcs12 = chilkat::Pfx::new();

let num_private_keys = jks.num_private_keys();
let mut i: i32 = 0;

// For each private key entry, get the private key and
// the associated certificate chain.
// Each private key is password protected.  Usually it is the same
// password as used for the keyed digest of the entire JKS.  
// However, this does not have to be.  The password is passed
// here to handle the possibility of each private key requiring
// a different password.
i = 0;
while i < num_private_keys {
    let priv_key = jks.get_private_key(&jks_password, i).unwrap();
    println!("{}", jks.get_private_key_alias(i).unwrap_or_default());
    let cert_chain = jks.get_cert_chain(i).unwrap();

    // Add the private key and it's associated certificate chain to the PKCS12.
    if pkcs12.add_private_key(&priv_key, &cert_chain).is_err() {
        println!("{}", pkcs12.last_error_text());

        return;
    }

    i = i + 1;
}

// Save the PKCS12 / PFX to a file.
// The password can be the same as the JKS password, or something new.
// (With the PKCS12 format, there is a single password for the entire contents
// of the file.  With the JKS format, there is flexibility in allowing each private key
// to have it's own password.)
let pkcs12_password = "myNewPassword".to_string();
if pkcs12.to_file(&pkcs12_password, "/pkcs12_files/myPfx.p12").is_err() {
    println!("{}", pkcs12.last_error_text());
} else {
    println!("Successfully saved to PKCS12 format.");
}