Re: Bus error in smtpctl spf walk

2018-03-07 Thread Otto Moerbeek 
On Wed, Mar 07, 2018 at 08:30:25AM +0100, Gilles Chehade wrote:

> On Tue, Mar 06, 2018 at 01:13:11PM +0100, Otto Moerbeek wrote:
> > On Tue, Mar 06, 2018 at 10:46:23AM +0100, Jan Johansson wrote:
> > 
> > > >Synopsis:Bus error in smtpctl spf walk (on certain domains)
> > > >Category:user
> > > >Environment:
> > >   System  : OpenBSD 6.3
> > >   Details : OpenBSD 6.3-beta (GENERIC.MP) #26: Fri Mar  2 22:56:04 
> > > MST 2018
> > >
> > > dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> > > 
> > >   Architecture: OpenBSD.amd64
> > >   Machine : amd64
> > > >Description:
> > > Got a mail with "Return-Path: 
> > > bounces+abcd1...@sendgrid.meetup.com" and wanted to add it to my white 
> > > list but smtpctl spf walk says "Bus error". Other domains like 
> > > facebookmail.com works without problem. 
> > > http://www.kitterman.com/spf/validate.html seems to think 
> > > sendgrid.meetup.com has a valid record.
> > > 
> > > >How-To-Repeat:
> > > echo sendgrid.meetup.com | smtpctl spf walk
> > > 
> > > >Fix:
> > > Not known
> > 
> > Try this,
> > 
> > -Otto
> > 
> > Index: spfwalk.c
> > ===
> > RCS file: /cvs/src/usr.sbin/smtpd/spfwalk.c,v
> > retrieving revision 1.5
> > diff -u -p -r1.5 spfwalk.c
> > --- spfwalk.c   26 Jan 2018 08:00:54 -  1.5
> > +++ spfwalk.c   6 Mar 2018 12:12:42 -
> > @@ -140,6 +140,8 @@ dispatch_txt(struct dns_rr *rr)
> > char *end;
> > ssize_t n;
> >  
> > +   if (rr->rr_type != T_TXT)
> > +   return;
> > n = parse_txt(rr->rr.other.rdata, rr->rr.other.rdlen, buf, sizeof(buf));
> > if (n == -1 || n == sizeof(buf))
> > return;
> > 
> 
> ok gilles@, the check can't hurt
> 
> I'm curious why we can even get rr_type != T_TXT when res_query_async()
> is called with a type == T_TXT though, I'll look into this to ensure we
> don't use a broken pattern in multiple places.

It is because there's a cname record involved:

;; QUESTION SECTION:
;sendgrid.meetup.com.   IN  TXT

;; ANSWER SECTION:
sendgrid.meetup.com.300 IN  CNAME   u3863915.wl166.sendgrid.net.
u3863915.wl166.sendgrid.net. 1800 INTXT "v=spf1 include:sendgrid.net 
~all"

-Otto

Re: Bus error in smtpctl spf walk

2018-03-06 Thread Gilles Chehade 
On Tue, Mar 06, 2018 at 01:13:11PM +0100, Otto Moerbeek wrote:
> On Tue, Mar 06, 2018 at 10:46:23AM +0100, Jan Johansson wrote:
> 
> > >Synopsis:  Bus error in smtpctl spf walk (on certain domains)
> > >Category:  user
> > >Environment:
> > System  : OpenBSD 6.3
> > Details : OpenBSD 6.3-beta (GENERIC.MP) #26: Fri Mar  2 22:56:04 
> > MST 2018
> >  
> > dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> > 
> > Architecture: OpenBSD.amd64
> > Machine : amd64
> > >Description:
> > Got a mail with "Return-Path: bounces+abcd1...@sendgrid.meetup.com" 
> > and wanted to add it to my white list but smtpctl spf walk says "Bus 
> > error". Other domains like facebookmail.com works without problem. 
> > http://www.kitterman.com/spf/validate.html seems to think 
> > sendgrid.meetup.com has a valid record.
> > 
> > >How-To-Repeat:
> > echo sendgrid.meetup.com | smtpctl spf walk
> > 
> > >Fix:
> > Not known
> 
> Try this,
> 
>   -Otto
> 
> Index: spfwalk.c
> ===
> RCS file: /cvs/src/usr.sbin/smtpd/spfwalk.c,v
> retrieving revision 1.5
> diff -u -p -r1.5 spfwalk.c
> --- spfwalk.c 26 Jan 2018 08:00:54 -  1.5
> +++ spfwalk.c 6 Mar 2018 12:12:42 -
> @@ -140,6 +140,8 @@ dispatch_txt(struct dns_rr *rr)
>   char *end;
>   ssize_t n;
>  
> + if (rr->rr_type != T_TXT)
> + return;
>   n = parse_txt(rr->rr.other.rdata, rr->rr.other.rdlen, buf, sizeof(buf));
>   if (n == -1 || n == sizeof(buf))
>   return;
> 

ok gilles@, the check can't hurt

I'm curious why we can even get rr_type != T_TXT when res_query_async()
is called with a type == T_TXT though, I'll look into this to ensure we
don't use a broken pattern in multiple places.

-- 
Gilles Chehade

https://www.poolp.org  @poolpOrg

Re: Bus error in smtpctl spf walk

2018-03-06 Thread Jan Johansson 
Otto Moerbeek  wrote:
> Try this,
> 
>   -Otto
> 
> Index: spfwalk.c
> ===
> RCS file: /cvs/src/usr.sbin/smtpd/spfwalk.c,v
> retrieving revision 1.5
> diff -u -p -r1.5 spfwalk.c
> --- spfwalk.c 26 Jan 2018 08:00:54 -  1.5
> +++ spfwalk.c 6 Mar 2018 12:12:42 -
> @@ -140,6 +140,8 @@ dispatch_txt(struct dns_rr *rr)
>   char *end;
>   ssize_t n;
>  
> + if (rr->rr_type != T_TXT)
> + return;
>   n = parse_txt(rr->rr.other.rdata, rr->rr.other.rdlen, buf, sizeof(buf));
>   if (n == -1 || n == sizeof(buf))
>   return;

Thats works perfect!

Thank you!

Re: Bus error in smtpctl spf walk

2018-03-06 Thread Ricardo Mestre 
Hi Otto,

Ugh! They have an "SPF record" and causes the error, your patch solves
the issue.

This will also prevent similar error(s) from other offenders, so FWIW
OK mestre@

On 13:13 Tue 06 Mar , Otto Moerbeek wrote:
> On Tue, Mar 06, 2018 at 10:46:23AM +0100, Jan Johansson wrote:
> 
> > >Synopsis:  Bus error in smtpctl spf walk (on certain domains)
> > >Category:  user
> > >Environment:
> > System  : OpenBSD 6.3
> > Details : OpenBSD 6.3-beta (GENERIC.MP) #26: Fri Mar  2 22:56:04 
> > MST 2018
> >  
> > dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> > 
> > Architecture: OpenBSD.amd64
> > Machine : amd64
> > >Description:
> > Got a mail with "Return-Path: bounces+abcd1...@sendgrid.meetup.com" 
> > and wanted to add it to my white list but smtpctl spf walk says "Bus 
> > error". Other domains like facebookmail.com works without problem. 
> > http://www.kitterman.com/spf/validate.html seems to think 
> > sendgrid.meetup.com has a valid record.
> > 
> > >How-To-Repeat:
> > echo sendgrid.meetup.com | smtpctl spf walk
> > 
> > >Fix:
> > Not known
> 
> Try this,
> 
>   -Otto
> 
> Index: spfwalk.c
> ===
> RCS file: /cvs/src/usr.sbin/smtpd/spfwalk.c,v
> retrieving revision 1.5
> diff -u -p -r1.5 spfwalk.c
> --- spfwalk.c 26 Jan 2018 08:00:54 -  1.5
> +++ spfwalk.c 6 Mar 2018 12:12:42 -
> @@ -140,6 +140,8 @@ dispatch_txt(struct dns_rr *rr)
>   char *end;
>   ssize_t n;
>  
> + if (rr->rr_type != T_TXT)
> + return;
>   n = parse_txt(rr->rr.other.rdata, rr->rr.other.rdlen, buf, sizeof(buf));
>   if (n == -1 || n == sizeof(buf))
>   return;
>

Re: Bus error in smtpctl spf walk

2018-03-06 Thread Otto Moerbeek 
On Tue, Mar 06, 2018 at 10:46:23AM +0100, Jan Johansson wrote:

> >Synopsis:Bus error in smtpctl spf walk (on certain domains)
> >Category:user
> >Environment:
>   System  : OpenBSD 6.3
>   Details : OpenBSD 6.3-beta (GENERIC.MP) #26: Fri Mar  2 22:56:04 
> MST 2018
>
> dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> 
>   Architecture: OpenBSD.amd64
>   Machine : amd64
> >Description:
> Got a mail with "Return-Path: bounces+abcd1...@sendgrid.meetup.com" 
> and wanted to add it to my white list but smtpctl spf walk says "Bus error". 
> Other domains like facebookmail.com works without problem. 
> http://www.kitterman.com/spf/validate.html seems to think sendgrid.meetup.com 
> has a valid record.
> 
> >How-To-Repeat:
> echo sendgrid.meetup.com | smtpctl spf walk
> 
> >Fix:
> Not known

Try this,

-Otto

Index: spfwalk.c
===
RCS file: /cvs/src/usr.sbin/smtpd/spfwalk.c,v
retrieving revision 1.5
diff -u -p -r1.5 spfwalk.c
--- spfwalk.c   26 Jan 2018 08:00:54 -  1.5
+++ spfwalk.c   6 Mar 2018 12:12:42 -
@@ -140,6 +140,8 @@ dispatch_txt(struct dns_rr *rr)
char *end;
ssize_t n;
 
+   if (rr->rr_type != T_TXT)
+   return;
n = parse_txt(rr->rr.other.rdata, rr->rr.other.rdlen, buf, sizeof(buf));
if (n == -1 || n == sizeof(buf))
return;