Perl

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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Perl

use chilkat();

$success = 0;

#  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.

$pkcs11 = chilkat::CkPkcs11->new();

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

#  The PIN should come from a secure source rather than being hard-coded.
$pin = "0000";

#  Normal user = 1
$userType = 1;

$success = $pkcs11->QuickSession($userType,$pin);
if ($success == 0) {
    print $pkcs11->lastErrorText() . "\r\n";
    exit;
}

#  Describe the private key object to be located on the HSM.
$json = chilkat::CkJsonObject->new();
$json->UpdateString("class","private_key");
$json->UpdateString("label","MySshKey");

$priv_handle = $pkcs11->FindObject($json);
if ($priv_handle == 0) {
    print $pkcs11->lastErrorText() . "\r\n";
    exit;
}

#  Find the corresponding public key by changing the class in the same template.
$json->UpdateString("class","public_key");

$pub_handle = $pkcs11->FindObject($json);
if ($pub_handle == 0) {
    print $pkcs11->lastErrorText() . "\r\n";
    exit;
}

#  Create an SSH key object that uses the HSM handles.  The key type may be "rsa" or "ec".
$key = chilkat::CkSshKey->new();
$keyType = "rsa";
$success = $key->UsePkcs11($pkcs11,$priv_handle,$pub_handle,$keyType);
if ($success == 0) {
    print $key->lastErrorText() . "\r\n";
    exit;
}

$ssh = chilkat::CkSsh->new();

$port = 22;
$success = $ssh->Connect("ssh.example.com",$port);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

#  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.
$success = $ssh->AuthenticatePk("mySshLogin",$key);
if ($success == 0) {
    print $ssh->lastErrorText() . "\r\n";
    exit;
}

print "Public-key authentication successful." . "\r\n";

$ssh->Disconnect();

$pkcs11->Logout();
$pkcs11->CloseSession();