Rust

SSH HSM Public Key Authentication

Demonstrates SSH public-key authentication using a private key stored on an HSM — a USB token or smart card — accessed through PKCS#11. A session is opened with the vendor's driver, the key handles are located, and an SshKey object is bound to them with UsePkcs11.

Background: The point of an HSM is that the private key is generated on the device and cannot be exported: the signing operation happens on the hardware, so the key material never reaches your application's memory or disk. Even a fully compromised host cannot yield a copy of the key. PKCS#11 is the vendor-neutral interface to such devices, which is why the driver path and the object-finding template are the only vendor-specific parts of this example.

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

// Demonstrates SSH public-key authentication using a private key stored on an HSM (a USB token
// or smart card) accessed through PKCS#11.
// 
// Note: Chilkat's PKCS#11 implementation runs on Windows, Linux, macOS, and other supported
// operating systems.

let pkcs11 = chilkat::Pkcs11::new();

// The PKCS#11 driver supplied by your HSM vendor: a .dll on Windows, a .so on Linux, or a
// .dylib on macOS.
pkcs11.set_shared_lib_path("C:/Program Files (x86)/Gemalto/IDGo 800 PKCS#11/IDPrimePKCS1164.dll");

// The PIN should come from a secure source rather than being hard-coded.
let pin = "0000".to_string();

// Normal user = 1
let user_type = 1;

if pkcs11.quick_session(user_type, &pin).is_err() {
    println!("{}", pkcs11.last_error_text());
    return;
}

// Describe the private key object to be located on the HSM.
let json = chilkat::JsonObject::new();
let _ = json.update_string("class", "private_key");
let _ = json.update_string("label", "MySshKey");

let priv_handle = pkcs11.find_object(&json);
if priv_handle == 0 {
    println!("{}", pkcs11.last_error_text());
    return;
}

// Find the corresponding public key by changing the class in the same template.
let _ = json.update_string("class", "public_key");

let pub_handle = pkcs11.find_object(&json);
if pub_handle == 0 {
    println!("{}", pkcs11.last_error_text());
    return;
}

// Create an SSH key object that uses the HSM handles.  The key type may be "rsa" or "ec".
let key = chilkat::SshKey::new();
let key_type = "rsa".to_string();
if key.use_pkcs11(&pkcs11, priv_handle, pub_handle, &key_type).is_err() {
    println!("{}", key.last_error_text());
    return;
}

let ssh = chilkat::Ssh::new();

let port = 22;
if ssh.connect("ssh.example.com", port).is_err() {
    println!("{}", ssh.last_error_text());
    return;
}

// The corresponding public key must already be installed on the SSH server for the account.
// The signing operation happens on the HSM -- the private key never leaves the device.
if ssh.authenticate_pk("mySshLogin", &key).is_err() {
    println!("{}", ssh.last_error_text());
    return;
}

println!("Public-key authentication successful.");

ssh.disconnect();

let _ = pkcs11.logout();
let _ = pkcs11.close_session();