| Re: FORMS, validating mail was sent [message #181950 is a reply to message #181948] |
Thu, 27 June 2013 19:13   |
Thomas 'PointedEars'
Messages: 701
Registered: October 2010
Karma: 0
|
Senior Member |
|
|
Gordon Burditt wrote:
>> Utter nonsense. An (standards-compliant) “MX” or “A” DNS record *never*
>> points to 127.0.0.1. In particular, an MX record never has an IP address
>> as its value, as I have already pointed out.
>
> You expect spammers, vandals, and viruses to generate standards-compliant
> DNS?
No, you are very confused.
> [non sequitur]
> An MX record is not supposed to have an IP address as it's value,
More, the value of an MX record is never interpreted as an IP address in the
first place, the same as the value of a CNAME record is never interpreted as
an IP address by any DNS client implementation that is not FUBAR.
> but there is a good chance that if it does (for the destination
> address) a good fraction of the mail will be delivered anyway.
Pray tell, which host will the mail be delivered to if it cannot be resolved
in the first place?
> […]
>> 127.0.0.1 is specified at most in the local host file, and resolving a
>
> There's nothing wrong with including "localhost" in a nameserver for
> a local LAN.
Depends.
>> domain name of a supposed e-mail address will *never* result in
>> 127.0.0.1.
>
> You're wrong, unless you're going to use the "(standards-compliant)"
> dodge.
It is no dodge, it is both the standard *and* the *implementation* of DNS.
> Some people don't know you shouldn't put IP addresses in MX records,
> especially those where it seems to work.
“Seems” is correct, because MX 127.0.0.1 is equivalent to 127.0.0.1.$ZONE,
_not_ to 127.0.0.1.
PointedEars
--
realism: HTML 4.01 Strict
evangelism: XHTML 1.0 Strict
madness: XHTML 1.1 as application/xhtml+xml
-- Bjoern Hoehrmann
|
|
|
|
| Re: FORMS, validating mail was sent [message #181960 is a reply to message #181931] |
Fri, 28 June 2013 09:43 |
Arno Welzel
Messages: 317
Registered: October 2011
Karma: 0
|
Senior Member |
|
|
Am 25.06.2013 15:19, schrieb Thomas 'PointedEars' Lahn:
> Gordon Burditt wrote:
[...]
>> Exim also has "sender verify" (which can be optionally enabled).
>> On starting to receive an incoming message, Exim starts to send a
>> bounce message back to the envelope-sender. If the bounce message
>> is refused (at the MAIL FROM: and RCPT TO: stage), so is the message.
>> The bounce message is never completely sent (and has no text) so
>> it's never delivered. If sender DNS or mail server goes down, the
>> message goes nowhere.
>
> That is the counter-measure I was talking about. It does not pertain to the
> “From” header field, but to the *Envelope*-From. Which is something that
> you cannot change with PHP's mail().
JFTR: Depending on the platform you use PHP you can - just pass an
optional parameter to sendmail (-f) to override the envelope-From:
mail('to(at)foobar(dot)example',
'subject',
'message',
'From: from(at)foobar(dot)example',
'-f from(at)foobar(dot)example');
Also see: <http://php.net/manual/en/function.mail.php>
--
Arno Welzel
http://arnowelzel.de
http://de-rec-fahrrad.de
|
|
|
|
Calendar
Search
Help
Members
Register
Login
Home
]