ReminderTokenUtils.php

<?php

class ReminderTokenUtils
{
  public function __construct ()
  {
  }

  /**
   * @param string $userDN
   * @param int $timeStamp
   * @return string
   * @throws Exception
   */
  public function generateToken (string $userDN, int $timeStamp, TaskGateway $gateway): string
  {
    $token = NULL;
    // Salt has been generated with APG.
    $salt  = '8onOlEsItKond';
    $payload = json_encode($userDN . $salt);
    // This allows the token to be different every time.
    $time = time();

    // Create hmac with sha256 alg and the key provided for JWT token signature in ENV.
    $token_hmac = hash_hmac("sha256", $time . $payload, $_ENV["SECRET_KEY"], TRUE);

    // We need to have a token allowed to be used within an URL.
    $token = $this->base64urlEncode($token_hmac);

    // Save token within LDAP
    $this->saveTokenInLdap($userDN, $token, $timeStamp, $gateway);

    return $token;
  }

  /**
   * @param string $userDN
   * @param string $token
   * NOTE : UID is the full DN of the user. (uid=...).
   * @param int $days
   * @return bool
   * @throws Exception
   */
  private function saveTokenInLdap (string $userDN, string $token, int $days, TaskGateway $gateway): bool
  {
    $result = FALSE;

    $currentTimestamp = time();
    // Calculate the future timestamp by adding days to the current timestamp (We actually adds number of seconds).
    $futureTimestamp = $currentTimestamp + ($days * 24 * 60 * 60);

    preg_match('/uid=([^,]+),ou=/', $userDN, $matches);
    $uid = $matches[1];
    $dn  = 'cn=' . $uid . ',' . 'ou=tokens' . ',' . $_ENV["LDAP_BASE"];

    $ldap_entry["objectClass"]    = ['top', 'fdTokenEntry'];
    $ldap_entry["fdTokenUserDN"]  = $userDN;
    $ldap_entry["fdTokenType"]    = 'reminder';
    $ldap_entry["fdToken"]      = $token;
    $ldap_entry["fdTokenTimestamp"] = $futureTimestamp;
    $ldap_entry["cn"]         = $uid;

    // set the dn for the token, only take what's between "uid=" and ",ou="


    // Verify if token ou branch exists
    if (!$this->tokenBranchExist('ou=tokens' . ',' . $_ENV["LDAP_BASE"], $gateway)) {
      // Create the branch
      $this->createBranchToken($gateway);
    }