OpenPGP_Crypt_RSA::convert_private_key PHP Method

    static function convert_private_key($packet)
    {
        return self::convert_key($packet, true);
    }

 /**
  */
 public function generateKey($opts)
 {
     $skey = $this->_generateSecretKeyPacket($opts['keylength'], 'OpenPGP_SecretKeyPacket');
     $id = new Horde_Mail_Rfc822_Address($opts['email']);
     if (strlen($opts['comment'])) {
         $id->comment[] = $opts['comment'];
     }
     if (strlen($opts['name'])) {
         $id->personal = $opts['name'];
     }
     /* This is the private key we are creating. */
     $key = new OpenPGP_Message(array($skey, new OpenPGP_UserIDPacket($id->writeAddress(array('comment' => true)))));
     $rsa = OpenPGP_Crypt_RSA::convert_private_key($skey);
     $rsa->setHash(Horde_String::lower($opts['hash']));
     $rsa_sign_func = array('RSA' => array($opts['hash'] => function ($data) use($rsa) {
         return array($rsa->sign($data));
     }));
     /* Create signature packet. */
     $sig = new OpenPGP_SignaturePacket($key, 'RSA', $opts['hash']);
     /* "Generic certification of a User ID and Public-Key packet." */
     $sig->signature_type = 0x10;
     /* Add subpacket information. */
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_KeyFlagsPacket(array(0x3));
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_PreferredSymmetricAlgorithmsPacket(array(0x9, 0x8, 0x7, 0x2));
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_PreferredHashAlgorithmsPacket(array(0x8, 0x9, 0xa, 0xb, 0x2));
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_PreferredCompressionAlgorithmsPacket(array(0x2, 0x1));
     $ks_prefs = new OpenPGP_SignaturePacket_KeyServerPreferencesPacket();
     $ks_prefs->no_modify = true;
     $sig->hashed_subpackets[] = $ks_prefs;
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_FeaturesPacket(array(0x1));
     if (isset($opts['expire'])) {
         $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_KeyExpirationTimePacket($opts['expire'] - time());
     }
     $sig->unhashed_subpackets[] = new OpenPGP_SignaturePacket_IssuerPacket(substr($skey->fingerprint, -16));
     $key[] = $sig;
     /* Create self-signature. */
     $sig->sign_data($rsa_sign_func);
     /* OpenPGP currently (as of April 2015) encrypts passphrases w/
      * AES-128 & SHA-1, so use this strategy. */
     if (strlen($opts['passphrase'])) {
         $cipher = new Crypt_AES(CRYPT_AES_MODE_CFB);
         $cipher->setKeyLength(128);
         $s2k = new OpenPGP_S2K(crypt_random_string(8), 2);
         $cipher->setKey($s2k->make_key($opts['passphrase'], 16));
         $iv = crypt_random_string(16);
         $this->_encryptPrivateKey($skey, $cipher, $s2k, $iv);
     }
     /* Encryption subkey. See RFC 4880 [5.5.1.2] (by convention, top-level
      * key is used for signing and subkeys are used for encryption) */
     $ekey = $this->_generateSecretKeyPacket($opts['keylength'], 'OpenPGP_SecretSubkeyPacket');
     /* Computing signature: RFC 4880 [5.2.4] */
     $sig = new OpenPGP_SignaturePacket(implode('', $skey->fingerprint_material()) . implode('', $ekey->fingerprint_material()), 'RSA', $opts['hash']);
     /* This is a "Subkey Binding Signature". */
     $sig->signature_type = 0x18;
     $sig->hashed_subpackets[] = new OpenPGP_SignaturePacket_KeyFlagsPacket(array(0xc));
     $sig->unhashed_subpackets[] = new OpenPGP_SignaturePacket_IssuerPacket(substr($skey->fingerprint, -16));
     $sig->sign_data($rsa_sign_func);
     if (strlen($opts['passphrase'])) {
         $this->_encryptPrivateKey($ekey, $cipher, $s2k, $iv);
     }
     $key[] = $ekey;
     $key[] = $sig;
     return new Horde_Pgp_Element_PrivateKey($key);
 }