Uncaught TypeError: stream_set_timeout(): Argument #1 ($stream) must be of type resource, bool given

[glwrba]

When trying to establish the SMTP connection, the code assumes that the socket being obtained is a valid one, and performs a call to set the stream_set_timeout. That's correct for a successful connection, however if a connection cannot be established the call to fsockopen returns a boolean FALSE which leads to an exception when trying to call the @stream_set_timeout function since it expects a handle rather than a boolean, leading to the below stacktrace and exception:

Fatal error: Uncaught TypeError: stream_set_timeout(): Argument #1 ($stream) must be of type resource, bool given in /opt/apache-2.4/sites/microforum.openservers.org/inc/mailhandlers/smtp.php:281 Stack trace: #0 /opt/apache-2.4/sites/microforum.openservers.org/inc/mailhandlers/smtp.php(281): stream_set_timeout(false, 5, 0) #1 /opt/apache-2.4/sites/microforum.openservers.org/inc/mailhandlers/smtp.php(199): SmtpMail->connect() #2 /opt/apache-2.4/sites/microforum.openservers.org/inc/functions.php(677): SmtpMail->send() #3 /opt/apache-2.4/sites/microforum.openservers.org/member.php(621): my_mail('glwrba@yahoo.co...', 'New registratio...', 'admin,\n\nThere i...') #4 {main} thrown in /opt/apache-2.4/sites/microforum.openservers.org/inc/mailhandlers/smtp.php on line 281

The snippet of code that fails is as below

`(Line 281) of inc/mailhandlers/smtp.php

function connect()
{
global $lang, $mybb;

            $this->connection = @fsockopen($this->host, $this->port, $error_number, $error_string, $this->timeout);
    
            // DIRECTORY_SEPARATOR checks if running windows
            if(function_exists('stream_set_timeout') && DIRECTORY_SEPARATOR != '\\')
            {
                    @stream_set_timeout($this->connection, $this->timeout, 0);
            }

`

The solution is to check the handle being returned, and in case of getting a FALSE boolean, we should immediately log the condition and return from the function with a FALSE flagging that something has failed while trying to send the mail via SMTP.

The snippet below represents one potential way to fix this issue

`function connect()
{
global $lang, $mybb;

            $this->connection = @fsockopen($this->host, $this->port, $error_number, $error_string, $this->timeout);

            if ( ! $this->connection )
                    {
                          $this->fatal_error("A connection cannot be established to the mail server specified.");
                            return false;

                  }

Said that, this is not the only change required since after doing so, the user is sent a positive notification on the screen , rather than a message indicating that something went wrong, i'm afraid more work is required in the upstream call chain so that when a FALSE is returned it must be interpreted as a failure and some action taken. I didn't dig too much yet but i think these changes should be incorporated to turn the mail process robust enough. ( it seems quite rough for now )