[Mailman-Users] DMARC hack

[Allan Hansen]

Stephen,

Much appreciated. 
Checking for aol.com and yahoo.com here alone will not work. I have a bunch of other subscribers that have
accounts with providers that are owned by Yahoo (mostly) and AOL, but whose addresses are not of this form.
I would have to do this for all addresses, to be safe.

If I do this and add the bit about the Reply-To, what would the code look like?

Yours,

	Allan

> On May 24, 2015, at 6:10 , Stephen J. Turnbull <stephen at xemacs.org> wrote:
> 
> Allan Hansen writes:
> 
>> 69,74d68
>> <     
>> <     # Added to deal with DMARC issuej
>> <     name, addrs = parseaddr(msg.get('from'))
>> <     addrs += '.invalid'
> 
> This is known to be a bad idea, as it increases the spam score at many
> sites (because the author's mail domain doesn't resolve).  Subscribers
> at such sites may have trouble receiving mail, and your list(s) may be
> tagged as suspicious.
> 
> I would recommend the From-munging approach:
> 
>    name, addr = parseadder(msg.get('from'))
>    if addr.endswith('aol.com') or addr.endswith('yahoo.com'):
>        # I forget what happens if it's a bare address
>        name = "%s (%s) via list" % (name if name else "Anonymous", addr)
>        addr = <list-post address>
>        del msg['from']
>        msg['from'] = formataddr((name, addr))
> 
> Mark (or you) probably have better code, and in some cases you may
> want to add the addr to the Reply-To field.
> 
>> <     del msg['from']
>> <     msg['from'] = formataddr((name, addrs))
>> \ No newline at end of file
>