SFTP using SSH2 extension

sftp.php

<?php

// Connect to sftp server
function sftp_connect(array $config)
{
  if (!function_exists('ssh2_connect')) {
    throw new Exception('Extension SSH2 not installed: check server configuration');
  }

  $options = array_merge(array(
    'host' => 'localhost',
    'port' => 22,
    'methods' => null,
    'fingerprint' => null,
    'username' => 'user', // SSH username
    'auth' => 'none', // 'none', 'key' or 'password'
    // if auth == key
    'pubkey' => '/path/to/key.pub',
    'privkey' => '/path/to/key.rsa',
    'passphrase' => null, // may not be supported, randomly, fuck this shit ><
    // if auth == password
    'password' => null
  ), $options);

  if ($ssh = ssh2_connect($config['host'], $config['port'], $config['methods'])) {
    if ($config['fingerprint']) {
      $fingerprint = ssh2_fingerprint($ssh, SSH2_FINGERPRINT_MD5 | SSH2_FINGERPRINT_HEX);
      if ($fingerprint != $config['fingerprint']) {
        throw new Exception(sprintf('Known host fingerprint "%s" does not match %s:%s fingerprint "%s". Possible man-in-the-middle attack ?', $config['fingerprint'], $config['host'], $config['port'], $fingerprint));
      }
    }
    $connected = false;
    switch ($config['auth']) {
      case 'key':
        $connected = ssh2_auth_pubkey_file($ssh, $config['username'], $config['pubkey'], $config['privkey'], $config['passphrase']);
        break;
      case 'password':
        $connected = ssh2_auth_password($ssh, $config['username'], $config['password']);
        break;
      case 'none':
        $connected = ssh2_auth_none($ssh, $config['username']);
        break;
      default:
        throw new Exception(sprintf('Invalid configuration: "%s" is not a valid value for "ssh2_auth". It must be one of "key", "password", or "none".', $config['auth']));
    }
    if (!$connected) {
      throw new Exception(sprintf('Failed authenticating to %s:%s using method %s', $config['host'], $config['port'], $config['auth']));
    }
  } else {
    throw new Exception(sprintf('Failed connecting to %s:%s', $config['host'], $config['port']));
  }

  return $ssh;
}

// Send file via SSH
function sftp_send_file($source, $dest, $server)
{
  if (!is_file($source)) {
    throw new Exception(sprintf('Source file "%s" does not exist', $source));
  }

  // $server = connection options or SSH resource ?
  $ssh = is_array($server) ? sftp_connect($server) : $server;

  return ssh2_scp_send($ssh, $source, $dest);
}