<?php
// this class generates new public/private keys using openssl
// it makes a couple calls directly against the openssl executable on your server
require_once('SemisecureLoginReimagined_RsaKeys_Base.php');
if (!class_exists('SemisecureLoginReimagined_RsaKeys')) {
	class SemisecureLoginReimagined_RsaKeys extends SemisecureLoginReimagined_RsaKeys_Base {

		// constructor
		// numbits should be either 512, 1024, or 2048
		// publicexponent should be either 10001 (F4 = 0x10001 = 65537) or 3 (0x3)
		function SemisecureLoginReimagined_RsaKeys($numbits = 1024, $publicexponent = 10001) {
			//$this->public_exponent = $publicexponent;
			//$this->num_bits = $numbits;
			$this->private_key = $this->generateNewPrivateKey($numbits, $publicexponent);
			list($this->modulus, $this->public_key) = $this->getModulusAndPublicKeyFromPrivateKey($this->private_key);
		}
		
		// get modulus and public key from privatekey via openssl
		function getModulusAndPublicKeyFromPrivateKey($privkey) {
			if (preg_match('/^-----BEGIN RSA PRIVATE KEY-----[^-]+-----END RSA PRIVATE KEY-----$/s', $privkey)) {
				$descriptorspec = array(
					0 => array("pipe", "r"),  // stdin is a pipe that the child will read from
					1 => array("pipe", "w")   // stdout is a pipe that the child will write to
					//2 => array("file", "/tmp/error-output.txt", "a") // stderr is a file to write to
				);
				$process = @proc_open("$this->opensslLocation rsa -pubout -modulus", $descriptorspec, $pipes);
				if (is_resource($process)) {
					fwrite($pipes[0], $privkey);
					fclose($pipes[0]);
					//$output = stream_get_contents($pipes[1]); // PHP5 only :(
					while (!feof($pipes[1]))
						$output .= fgets($pipes[1]);
					$output = trim($output);
					fclose($pipes[1]);
					@proc_close($process);
					if (preg_match('/^Modulus=(.+)(-----BEGIN PUBLIC KEY-----[^-]+-----END PUBLIC KEY-----)$/s', $output, $matches)) {
						return array(
							trim($matches[1]),
							trim($matches[2])
						);
					}
				}
			}
			return array('', '');
		}
		
		// generates private key via openssl
		function generateNewPrivateKey($numbits = 1024, $publicexponent = 10001) {
			if ($publicexponent == 10001) {
				$e = '-f4';
				$this->public_exponent = 10001;
			}
			else {
				$e = '-3';
				$this->public_exponent = 3;
			}
				
			$numbits = (int)$numbits;
			switch($numbits) {
				case 512:
				case 1024:
				case 2048:
				case 3072:
					$nbits = $numbits;
					break;
				default:
					$nbits = 1024;
					break;
			}
			$this->num_bits = $nbits;
			
			$privkey = @shell_exec("$this->opensslLocation genrsa $e $nbits");
			return trim($privkey);
		}
	}
}
?>