[aur-dev] [PATCH] valid_email :: add dns check

[Lukas Fleischer]

On Mon, Mar 19, 2012 at 09:48:36PM +0100, BlackEagle wrote:
> When an email address is of the correct format check if there is an mx
> record for the domain part. This forces people wanting to trash
> something in aur to use a domain part with an mx record.
> 
> This will not stop invalid email, it only adds an extra check and a
> possible help for typos.
> 
> Signed-off-by: BlackEagle <ike.devolder at gmail.com>
> ---
>  web/lib/aur.inc.php |    9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/web/lib/aur.inc.php b/web/lib/aur.inc.php
> index c662b80..7e9d7de 100644
> --- a/web/lib/aur.inc.php
> +++ b/web/lib/aur.inc.php
> @@ -80,7 +80,14 @@ function check_sid($dbh=NULL) {
>  # verify that an email address looks like it is legitimate
>  #
>  function valid_email($addy) {
> -	return (filter_var($addy, FILTER_VALIDATE_EMAIL) !== false);
> +	if (filter_var($addy, FILTER_VALIDATE_EMAIL) === false)
> +		return false;

This isn't noted down for the AUR yet but we always use opening and
closing braces in other Arch projects, such as pacman (even if it's just
a one-line block). It probably makes sense to add such a rule to our
coding guidelines.

Could you please change that when resubmitting the patch? I'll take care
of adding that to our guidelines later...

> +
> +	$domain = substr($addy, strrpos($addy, '@')+1);

Please add spaces before and after the plus sign (it should look like
"strrpos($addy, '@') + 1").

> +	if (!checkdnsrr($domain, 'MX') || checkdnsrr($domain, 'A'))

That check doesn't look correct to me. Why would we reject mail
addresses if there's an A record for the domain part? You probably
forgot parentheses and/or a negation ("!") here.

Also, I'm not sure why you're checking for A records at all? Could you
please elaborate on this?

Oh, and don't forget to add braces here as well :)

> +		return false;
> +
> +	return true;
>  }
>  
>  # a new seed value for mt_srand()
> -- 
> 1.7.9.4