Re: spamd and outlook.com

[Reyk Floeter]

On Fri, Apr 21, 2017 at 11:59:20AM +0200, Peter N. M. Hansteen wrote:
> On Fri, Apr 21, 2017 at 11:25:14AM +0200, Markus Rosjat wrote:
> > 
> > so if you have spamd in place in greylisting mode and you have customers
> > that work with people who use Office365 as a service you will get calls that
> > emails are delayed for a freaking long time and if you check the ip range
> > that outlook.com could send from you get scared.
> 
> start with
> 
> $ host -ttxt outlook.com
> 
> and follow the includes to the very end. Then weep.
> 
> TL;DR: last time I looked that expanded to eighty-some *networks* of varying 
> sizes.
> 
> https://github.com/akpoff/spf_fetch fed the relevant domains is one solution,
> and in addition you will find my collection of manually maintained SPF 
> sedimentation 
> is available at https://home.nuug.no/~peter/nospamd 
> 

I use the attached script to fetch the SPF entries recursively, in a
plain text format that can be fed into pfctl.

outlook.com gives me 82 networks.

Reyk

---snip---
#!/usr/bin/perl

# Copyright (c) 2016 Reyk Floeter <r...@openbsd.org>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

$domain = shift @ARGV or die "usage: $0 domain";

sub parsespf
{
        my $domain = shift;
        my @foo = `nslookup -q=TXT $domain`;
        my @results = ();

        foreach (@foo) {
                next if not /$domain\ttext/;
                next if not s/$domain\ttext = "v=spf1([^"]+)"/$1/;

                @results = split /\s+/;
                foreach (@results) {
                        next if /.all/;
                        if (s/^ip[46]://) {
                                print "$_\n";
                        } elsif (s/^(redirect|include)[:=]//) {
                                print "\n#$_\n";
                                parsespf($_);
                        }
                } 
        } 
}

parsespf($domain);

0;