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Posted to users@spamassassin.apache.org by rstarkov <ws...@starkov.name> on 2011/04/05 12:08:13 UTC
RCVD_IN_SORBS_DUL on my own emails to self
Like so many people, I get a dynamic IP from my ISP. Right now, any emails I
send to myself show up as "RCVD_IN_SORBS_DUL". Somehow I thought that as
long as my SMTP server isn't blacklisted, something like this wouldn't
happen.
The exact message is: RCVD_IN_SORBS_DUL RBL: SORBS: sent directly from
dynamic IP address
* [82.6.105.32 listed in dnsbl.sorbs.net]
So what should I do now, just keep resetting my modem until I get an IP that
isn't blacklisted? Doesn't that make this rule completely useless, blocking
email from a lot of legitimate users?
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by David B Funk <db...@engineering.uiowa.edu>.
On Wed, 6 Apr 2011, rstarkov wrote:
> Ah right. Yes, it's qmail. It appears that RFC3848 is not directly supported
> by my managed server... It runs Plesk, and all I can find are a couple of
> lone voices asking for this to become supported (met with silence or people
> not knowing what on earth is being talked about). It appears to be a
> comparatively little known rfc :/
>
> Thanks very much for helping me figure out what exactly is wrong here. If I
> feel brave enough to upgrade whatever needs upgrading by myself then I'll
> know where to start; fortunately the managed server comes with such an
> option.
>
FWIW, sendmail & postfix both get it right.
There's a patch that can be applied to qmail to make it work too.
(see: http://www.fehcom.de/qmail/smtpauth.html##PATCHES )
--
Dave Funk University of Iowa
<dbfunk (at) engineering.uiowa.edu> College of Engineering
319/335-5751 FAX: 319/384-0549 1256 Seamans Center
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#include <std_disclaimer.h>
Better is not better, 'standard' is better. B{
Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by rstarkov <ws...@starkov.name>.
> Spamassassin does honor authentication headers that are -properly- added.
> (see rfc3848 for an official statement of what needs to be done). In your
> example that MTA (qmail?) did not add proper authentication headers.
Ah right. Yes, it's qmail. It appears that RFC3848 is not directly supported
by my managed server... It runs Plesk, and all I can find are a couple of
lone voices asking for this to become supported (met with silence or people
not knowing what on earth is being talked about). It appears to be a
comparatively little known rfc :/
Thanks very much for helping me figure out what exactly is wrong here. If I
feel brave enough to upgrade whatever needs upgrading by myself then I'll
know where to start; fortunately the managed server comes with such an
option.
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by David B Funk <db...@engineering.uiowa.edu>.
On Wed, 6 Apr 2011, rstarkov wrote:
>
[snip..]
> > if your MTA properly marks mail received with authentication and inserts
> > authentication headers, SpamAssassin will take those headers and dynamic
> > RBL checks should not apply.
>
> I don't think it does. Here's a sample email in its entirety:
> http://pastebin.com/3hR48LqX
>
> What sort of headers should be added? Should it mention something about
> ESMTP in the "Received" header or something like that?
>
Spamassassin does honor authentication headers that are -properly- added.
(see rfc3848 for an official statement of what needs to be done). In your
example that MTA (qmail?) did not add proper authentication headers.
--
Dave Funk University of Iowa
<dbfunk (at) engineering.uiowa.edu> College of Engineering
319/335-5751 FAX: 319/384-0549 1256 Seamans Center
Sys_admin/Postmaster/cell_admin Iowa City, IA 52242-1527
#include <std_disclaimer.h>
Better is not better, 'standard' is better. B{
Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by rstarkov <ws...@starkov.name>.
> no. You should just properly configure trusted_networks and
> internal_networks so all dnsbl rules would be used as they should.
OK, so I need to add all of my ISPs dynamic IPs as trusted? (as suggested in
http://wiki.apache.org/spamassassin/DynablockIssues)
It sounds backwards though; the above will surely not help when I visit a
friend and connect via their dynamic IP? Or via my 3G broadband? The first
Received header will still be from some random dynamic IP address.
> if your MTA properly marks mail received with authentication and inserts
> authentication headers, SpamAssassin will take those headers and dynamic
> RBL checks should not apply.
I don't think it does. Here's a sample email in its entirety:
http://pastebin.com/3hR48LqX
What sort of headers should be added? Should it mention something about
ESMTP in the "Received" header or something like that?
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> > You should use SMTP authentication when posting through your SMTP
> > server.i guess you are not.
> > (And the SMTP server should not be on dynamic IP, of course)
On 05.04.11 04:29, rstarkov wrote:
> I am using SMTP authentication, and it's on a static IP. It's the PC with my
> Thunderbird that's on a dynamic IP.
ok
> > The dynamic checks are only run at internal network border, which means,
> > mail should not get delivered from such hosts directly.
> > That requires properly configured internal_networks.
> Right, I'm just misusing a rule, aren't I. I think I should just turn it
> off.
no. You should just properly configure trusted_networks and
internal_networks so all dnsbl rules would be used as they should.
> > And, of course, your MTA must put authentication info to mail headers in
> > the format SA understands (so it knows SMTP AUTH was used and therefore
> > skips those RBL checks).
>
> I'm not sure what exactly you mean here - could you drop a keyword or two so
> I could google?
"spamassassin dynamic"
http://wiki.apache.org/spamassassin/TrustPath
> My MTA authenticates to the SMTP server because the SMTP
> server will not talk to anyone who hasn't, but I don't think either the MTA
> or my server add any headers to indicate that this has occurred.
if your MTA properly marks mail received with authentication and inserts
authentication headers, SpamAssassin will take those headers and dynamic
RBL checks should not apply.
you should paste such mail to pastebin/whatever and send the link here so we
(on this list) could see what's the problem
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by rstarkov <ws...@starkov.name>.
> You should use SMTP authentication when posting through your SMTP
> server.i guess you are not.
> (And the SMTP server should not be on dynamic IP, of course)
I am using SMTP authentication, and it's on a static IP. It's the PC with my
Thunderbird that's on a dynamic IP.
> The dynamic checks are only run at internal network border, which means,
> mail should not get delivered from such hosts directly.
> That requires properly configured internal_networks.
Right, I'm just misusing a rule, aren't I. I think I should just turn it
off.
> And, of course, your MTA must put authentication info to mail headers in
> the
> format SA understands (so it knows SMTP AUTH was used and therefore skips
> those RBL checks).
I'm not sure what exactly you mean here - could you drop a keyword or two so
I could google? My MTA authenticates to the SMTP server because the SMTP
server will not talk to anyone who hasn't, but I don't think either the MTA
or my server add any headers to indicate that this has occurred.
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> > your IP isn't backlisted. It's listed as a DUL, which is correct:
[...]
> > You'll have to use a smarthost or get a static/business connection.
On 05.04.11 03:29, rstarkov wrote:
> I'm not sure I understand this bit. From what I see on
> http://en.wikipedia.org/wiki/Smart_host, I already use a "smart host", in
> that the SMTP server specified in my mail client is not an open relay. Or is
> there more to this?
You should use SMTP authentication when posting through your SMTP server.
i guess you are not.
(And the SMTP server should not be on dynamic IP, of course)
> One other thing I don't get is this: surely anyone who uses something like
> Thunderbird to send their email from a dynamic IP like this one will
> invariably trigger this rule?
The dynamic checks are only run at internal network border, which means,
mail should not get delivered from such hosts directly.
That requires properly configured internal_networks.
If you use the same server for MX and for SMTP, and you run spam checks on
it, you can configure trusted_networks to include dynamic IP addresses ytou
are sending mail from, so they are not checked.
SMTP authentication does the same but I found it better.
And, of course, your MTA must put authentication info to mail headers in the
format SA understands (so it knows SMTP AUTH was used and therefore skips
those RBL checks).
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Nigel Frankcom <ni...@blue-canoe.com>.
On Sun, 10 Apr 2011 00:59:29 +0200, Michelle Konzack
<li...@tamay-dogan.net> wrote:
>Hello rstarkov,
>
>Am 2011-04-09 15:50:36, hacktest Du folgendes herunter:
>> Does your header definitely include an ESMTP marker as per the RFC? Mine
>> didn't; that was the real issue. We didn't find a bug in this rule. So I
>> guess SpamAssassin doesn't have a way to find out that you were
>> authenticated and that it was your own message.
>
>Yes, look into my previous message...
>
>However, I find SORBS too errorprone and not very reliabel!
>
>Thanks, Greetings and nice Day/Evening
> Michelle Konzack
I'd agree that one in spades. I'm still getting stuff bounce from
cached entries months after I cleared the last SORBS issue. That was
the 3rd time I've had to do so and I've been on static from the get go
(15 years +).
My ISP didn't help overly. BT decided that all issues relating to
rbl's are abuse issues and should be dealt with by that department; it
might have helped if they told said department and actually trained
the poor sods.
Saying that, no amount of training helps with SORBS. IMVHO SORBS gives
rbl's an undeserved bad name. Additionally, BT's approach of 'we are
big ergo you do what we say' doesn't add much in the way of help
either.
After many years I'm moving off BT, though that is because of their
billing and the incompetence there makes their rbl handling look like
it's 6 sigma.
I've defended BT for years, seems I was naive.
Expect to see me in SORBS soon :-D
Nigel
Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by John Hardin <jh...@impsec.org>.
On Sun, 10 Apr 2011, Jonathan Nichols wrote:
> back on topic... is there a way to lower the score for a particular
> ruleset for certain hosts/clients?
I assume you don't want to just use whitelist_from_rcvd for this?
An alternative would be to write a header rule that checks the last
external hop for the target hosts/clients (by name or, more reliably if
not dynamic, by IP address), and score it a few points negative. If you
want to be more specific, write metas that join the "specific host/client"
rule and the other particular rules you want to offset, and score the
metas instead.
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> > Am 2011-04-09 15:50:36, hacktest Du folgendes herunter:
> >> Does your header definitely include an ESMTP marker as per the RFC? Mine
> >> didn't; that was the real issue. We didn't find a bug in this rule. So I
> >> guess SpamAssassin doesn't have a way to find out that you were
> >> authenticated and that it was your own message.
> On Apr 9, 2011, at 5:59 PM, Michelle Konzack wrote:
> > Yes, look into my previous message...
> >
> > However, I find SORBS too errorprone and not very reliabel!
> >
> > Thanks, Greetings and nice Day/Evening
> > Michelle Konzack
On 10.04.11 15:30, Jonathan Nichols wrote:
> Sadly, I have to agree and have been dealing with that for a while. in
> fact, I wonder if this message will ever make it to the list or if
> apache.org will bounce it because of SORBS.. :/
>
> back on topic... is there a way to lower the score for a particular
> ruleset for certain hosts/clients?
there's trusted_networks setting that will make SA skip checking of those
IP's.
However blacklists like PBL and DUL are only being checked on
internal_networks boundary, that is, only for machines that deliver mail to
your network.
If the problem lies in dialup machines sending mail directly to your
mailhost without authentication (or your mailhost does not mark
authenticated mail the way SA understands), trusted_networks should help
here.
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Jonathan Nichols <jn...@pbp.net>.
On Apr 9, 2011, at 5:59 PM, Michelle Konzack wrote:
> Hello rstarkov,
>
> Am 2011-04-09 15:50:36, hacktest Du folgendes herunter:
>> Does your header definitely include an ESMTP marker as per the RFC? Mine
>> didn't; that was the real issue. We didn't find a bug in this rule. So I
>> guess SpamAssassin doesn't have a way to find out that you were
>> authenticated and that it was your own message.
>
> Yes, look into my previous message...
>
> However, I find SORBS too errorprone and not very reliabel!
>
> Thanks, Greetings and nice Day/Evening
> Michelle Konzack
>
Sadly, I have to agree and have been dealing with that for a while. in fact, I wonder if this message will ever make it to the list or if apache.org will bounce it because of SORBS.. :/
back on topic... is there a way to lower the score for a particular ruleset for certain hosts/clients?
Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Michelle Konzack <li...@tamay-dogan.net>.
Hello rstarkov,
Am 2011-04-09 15:50:36, hacktest Du folgendes herunter:
> Does your header definitely include an ESMTP marker as per the RFC? Mine
> didn't; that was the real issue. We didn't find a bug in this rule. So I
> guess SpamAssassin doesn't have a way to find out that you were
> authenticated and that it was your own message.
Yes, look into my previous message...
However, I find SORBS too errorprone and not very reliabel!
Thanks, Greetings and nice Day/Evening
Michelle Konzack
--
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by rstarkov <ws...@starkov.name>.
> It seems, ther is a bug in thsis SA rule... because from the header I
> see, that I was authenticated and SA see this too, so why it does reject
> MY OWN MESSAGE?
Does your header definitely include an ESMTP marker as per the RFC? Mine
didn't; that was the real issue. We didn't find a bug in this rule. So I
guess SpamAssassin doesn't have a way to find out that you were
authenticated and that it was your own message.
>> One other thing I don't get is this: surely anyone who uses something
>> like
>> Thunderbird to send their email from a dynamic IP like this one will
>> invariably trigger this rule? I must have had a major misunderstanding
>> about
>> SMTP then; what
>> http://wiki.apache.org/spamassassin/Rules/RCVD_IN_SORBS_DUL
>> seems to be saying is that NOBODY with a dynamic IP is "supposed" to be
>> talking to an SMTP server... which just makes no sense to me.
It was actually a minor misunderstanding. I didn't know that there was a
special way to mark a "Received" entry as "authenticated", which, I think,
tells SpamAssassin that it doesn't need to check if earlier hosts were
dynamic (in fact I wonder if this tells SA to ignore a whole lot of rules
that would otherwise trigger on my originating Received entry).
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Michelle Konzack <li...@tamay-dogan.net>.
Hello Matus UHLAR - fantomas,
Am 2011-04-10 15:00:53, hacktest Du folgendes herunter:
> SA never rejects messages. Your problem must lie elsewhere...
The problem is, it scores to high FOR ME! I have checked others and it
is working correctly, but if I send from my IP at <free.fr> it is OK,
not from an IP of <o2.de> e.g. <89.204.137.232>...
Thanks, Greetings and nice Day/Evening
Michelle Konzack
--
##################### Debian GNU/Linux Consultant ######################
Development of Intranet and Embedded Systems with Debian GNU/Linux
itsystems@tdnet France EURL itsystems@tdnet UG (limited liability)
Owner Michelle Konzack Owner Michelle Konzack
Apt. 917 (homeoffice)
50, rue de Soultz Kinzigstraße 17
67100 Strasbourg/France 77694 Kehl/Germany
Tel: +33-6-61925193 mobil Tel: +49-177-9351947 mobil
Tel: +33-9-52705884 fix
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> Am 2011-04-05 03:29:44, hacktest Du folgendes herunter:
> > I'm not sure I understand this bit. From what I see on
> > http://en.wikipedia.org/wiki/Smart_host, I already use a "smart host", in
> > that the SMTP server specified in my mail client is not an open relay. Or is
> > there more to this?
On 10.04.11 00:44, Michelle Konzack wrote:
> I have the same problem! If I activate the SORBS DUL, I can not even
> send over my own SMTP-Relay <mail.tamay-dogan.net> (even authenticated).
activate where?
> It seems, ther is a bug in thsis SA rule... because from the header I
> see, that I was authenticated and SA see this too, so why it does reject
> MY OWN MESSAGE?
SA never rejects messages. Your problem must lie elsewhere...
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Michelle Konzack <li...@tamay-dogan.net>.
Hello rstarkov,
Am 2011-04-05 03:29:44, hacktest Du folgendes herunter:
> I'm not sure I understand this bit. From what I see on
> http://en.wikipedia.org/wiki/Smart_host, I already use a "smart host", in
> that the SMTP server specified in my mail client is not an open relay. Or is
> there more to this?
I have the same problem! If I activate the SORBS DUL, I can not even
send over my own SMTP-Relay <mail.tamay-dogan.net> (even authenticated).
It seems, ther is a bug in thsis SA rule... because from the header I
see, that I was authenticated and SA see this too, so why it does reject
MY OWN MESSAGE?
> One other thing I don't get is this: surely anyone who uses something like
> Thunderbird to send their email from a dynamic IP like this one will
> invariably trigger this rule? I must have had a major misunderstanding about
> SMTP then; what http://wiki.apache.org/spamassassin/Rules/RCVD_IN_SORBS_DUL
> seems to be saying is that NOBODY with a dynamic IP is "supposed" to be
> talking to an SMTP server... which just makes no sense to me.
1+
Thanks, Greetings and nice Day/Evening
Michelle Konzack
--
##################### Debian GNU/Linux Consultant ######################
Development of Intranet and Embedded Systems with Debian GNU/Linux
itsystems@tdnet France EURL itsystems@tdnet UG (limited liability)
Owner Michelle Konzack Owner Michelle Konzack
Apt. 917 (homeoffice)
50, rue de Soultz Kinzigstraße 17
67100 Strasbourg/France 77694 Kehl/Germany
Tel: +33-6-61925193 mobil Tel: +49-177-9351947 mobil
Tel: +33-9-52705884 fix
<http://www.itsystems.tamay-dogan.net/> <http://www.flexray4linux.org/>
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by rstarkov <ws...@starkov.name>.
> your IP isn't backlisted. It's listed as a DUL, which is correct:
OK, right, that makes sense.
> You'll have to use a smarthost or get a static/business connection.
I'm not sure I understand this bit. From what I see on
http://en.wikipedia.org/wiki/Smart_host, I already use a "smart host", in
that the SMTP server specified in my mail client is not an open relay. Or is
there more to this?
One other thing I don't get is this: surely anyone who uses something like
Thunderbird to send their email from a dynamic IP like this one will
invariably trigger this rule? I must have had a major misunderstanding about
SMTP then; what http://wiki.apache.org/spamassassin/Rules/RCVD_IN_SORBS_DUL
seems to be saying is that NOBODY with a dynamic IP is "supposed" to be
talking to an SMTP server... which just makes no sense to me.
Any help will be very much appreciated!
--
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Re: RCVD_IN_SORBS_DUL on my own emails to self
Posted by Yet Another Ninja <ax...@gmail.com>.
On 2011-04-05 12:08, rstarkov wrote:
>
> Like so many people, I get a dynamic IP from my ISP. Right now, any emails I
> send to myself show up as "RCVD_IN_SORBS_DUL". Somehow I thought that as
> long as my SMTP server isn't blacklisted, something like this wouldn't
> happen.
>
> The exact message is: RCVD_IN_SORBS_DUL RBL: SORBS: sent directly from
> dynamic IP address
> * [82.6.105.32 listed in dnsbl.sorbs.net]
>
> So what should I do now, just keep resetting my modem until I get an IP that
> isn't blacklisted? Doesn't that make this rule completely useless, blocking
> email from a lot of legitimate users?
your IP isn't backlisted. It's listed as a DUL, which is correct:
-> 32.105.6.82.in-addr.arpa.
type = PTR, class = 1, ttl = 604800, dlen = 50
host = cpc1-cmbg8-0-0-cust287.5-4.cable.virginmedia.co
That IP is also listed in Spamhaus's PBL:
http://www.spamhaus.org/query/bl?ip=82.6.105.32
which is also correct.
You'll have to use a smarthost or get a static/business connection.