Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Mark Sapiro
On 10/18/2017 03:41 PM, Jordan Brown wrote: > On 10/18/2017 11:35 AM, Mark Sapiro wrote: >> DMARC is not the problem. It is perfectly reasonable for say, irs.gov >> to publish DMARC p=reject as long as mail From: irs.gov is not an >> employees personal post to an email list. Presumably the IRS

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 03:42 PM, Dimitri Maziuk wrote: Because the very first $relayhost may apply transport encoding. You have to compute the hash before that happens. It's my understanding that DKIM is usually applied by the egress MSA / MTA. I guess an MSA could apply DKIM itself. It would need to

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Dimitri Maziuk
On 10/18/2017 04:26 PM, Grant Taylor via Mailman-Users wrote: > On 10/18/2017 02:10 PM, Dimitri Maziuk wrote: > > Do I understand you correctly to mean to create the signature before > applying transport encoding? > >> Only, you can't do that on the MX, it has to be done on the client. > > Why

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 02:10 PM, Dimitri Maziuk wrote: They are different ASCII representations of the same byte, yes. They are not the same text. Hum. I wonder if we have been talking about slightly different things. I've been referring to "ü" being displayed the same in MUAs which is interpreting

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Dimitri Maziuk
On 10/18/2017 02:32 PM, Grant Taylor via Mailman-Users wrote: > I'm referring to the difference between: > >  - ü  - ASCII (?) >  - =C3=BC - quoted-printable >  - w7w=   - base 64 >  - - HTML > > All four representations are for the *same* letter / character / glyph / > byte(s). They are

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 01:07 PM, Dimitri Maziuk wrote: 17 == 0x11. "17" != "0x11". Which was precisely the point: if your MTA, say, does unicodedata.normalize( 'NFKD' ... ), and turns u-umlaut into a regular "u", you may consider it benign. Many won't. I would not consider that benign at all. I'm

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Dimitri Maziuk
On 10/18/2017 01:30 PM, Grant Taylor via Mailman-Users wrote: > The (decimal) number 17 can be encoded multiple ways: > > 10001 = binary  base  2 >    25 = hex base  6 >    21 = octal   base  8 >    17 = decimal base 10 >    11 = hexadecimal base 16 > > All five encoded

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 12:35 PM, Mark Sapiro wrote: DMARC is not the problem. It is perfectly reasonable for say, irs.gov to publish DMARC p=reject as long as mail From: irs.gov is not an employees personal post to an email list. Presumably the IRS would have rules against that. The problem is when

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Mark Sapiro
On 10/18/2017 11:14 AM, Grant Taylor via Mailman-Users wrote: > > I think it will be interesting to see what happens as more and more > domains adopt DMARC, including those that use p=reject.  Especially with > some of governmental institutions purportedly being mandated to use > DMARC.  -  IMHO,

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 11:51 AM, Dimitri Maziuk wrote: Like tnеtсоnsulting.nеt being a benign minor encoding change in a couple of characters? No. That is not a simple content encoding change. Content (re)encoding changes the representation of the same encoded data. <е> 1077, Hex 0435, Octal 2065

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 11:50 AM, Mark Sapiro wrote: ... This is the crux of our disagreement. The outbound message is still the original author's message, albeit slightly altered by subject prefixing, content filtering and/or other transformations to conform with list policies. I don't agree that it is a

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Dimitri Maziuk
On 10/18/2017 11:37 AM, Grant Taylor via Mailman-Users wrote: > I believe I remember (but can't point to) something in the DKIM spec > that referenced the possibility that the DKIM signature could be broken > by things as benign as an MTA doing a content transfer encoding > conversion.  -  I have

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Mark Sapiro
On 10/18/2017 09:31 AM, Grant Taylor via Mailman-Users wrote: > > Um  My interpretation of 6854 § 1 and § 4 makes me think that an > empty group list is perfectly acceptable.  Further, the group list can > be non-empty and contain the lists posting address. True, but in either case it still

Re: [Mailman-Users] cause of bounces

2017-10-18 Thread Grant Taylor via Mailman-Users
On 10/18/2017 09:18 AM, Dimitri Maziuk wrote: Then you seem to misunderstand what crypto signatures actually do. I believe I understand what the crypto signatures actually do. We are each entitled to decide what to actually do based on the result of the crypto signature (in)validity. If