Hi Pete,

Here are the individual answers to your questions:

 - Are you objecting to recipes in general, or are you only
   objecting to JSON-encoded recipes?

I am objecting to the current architecture of recipes that allows
structural state manipulation on the transport layer. Encoding
this structural complexity in JSON is compounding the risk.

The specific parsing differential unique to JSON here is the lack
of strict object-key ordering and duplicate key handling in
standard JSON specs. If a Milter parser evaluates a nested recipe
payload differently than the downstream MTA engine, the
cryptographic canonicalization is shattered. 15 years of DKIM1
proved that flat, native tag-value structures are inherently
immune to this exact category of serialization differentials. Why
did DKIM1 work without JSON for 15 years?

 - What text do you want to add to what section of what document?
   [Regarding y2k38]

This is not a matter of a local text patch in the Security
Considerations. The wire format specification itself needs to
enforce strict boundaries. If timestamp and expiry tags are not
explicitly bound to deterministic datatypes (like uint64_t
equivalency) on the wire, the protocol invites overflow
vulnerabilities on legacy architectures.

 - Do you see DKIM as securing critical infrastructure? Please
   explain.

Yes, absolutely. Global email transport is critical nfrastructure
(CRITIS). National grid operators, public administrations, and
educational networks rely on DKIM to protect their core
communications from spoofing and manipulation. Designing an
internet standard under the assumption that it does not secure
critical infrastructure is a fundamental violation of OWASP Top
10: Insecure Design principles.

 - This is not a discussion I'm willing to have on this list.
   I'll write to you separately about this topic. [Regarding
   Running Code]

Pete, to me it seems you do not like qualified architectural
discussions on list.

Did you forget the fundamental rules the IETF was built on: "We
believe in Rough Consensus and Running Code."? But actually,
there is no running code. Defining Rough Consensus while
bypassing the reality of broken implementations at the edge nodes
degrades a core IETF principle into theoretical debate.

 - As the editor of RFC 5322, I can tell you that the parsing
   differentials between 5322 parsers make parsing differentials
   between JSON parsers look downright quaint...

Arguing that we should introduce nested JSON parsing
differentials into the transport layer just because legacy RFC
5322 parsers are already structurally flawed is an architectural
fallacy [RFC 5322, OWASP-Richtlinien zu Insecure Design]. We
should minimize parsing complexity at the trust boundaries, not
compound it. You SHOULD consider consulting John Klensin.

 - I'm not sure what you're referring to. Please cite a specific
   message.

I am referring to Bron's explicit acknowledgment on this list
regarding the operational failure of the current design at
inbound edge gateways.

BTW: Bron already confirmed that this design would possibly not
work on Inbound Edge Gateways. If the recipe model cannot survive
the reality of inbound boundary validation, the design is
fundamentally faulty.

Operators in the real world require deterministic security, not
administrative consensus.

Regards,

Timo

It looks like Pete Resnick aimed to say:
> Hi Timo,
> 
> Please answer the below questions individually. Copy and paste them into 
> your answer if you need to.
> 
> On 10 Sep 2026, at 15:59, Timo Gerke wrote:
> 
>> Shifting Parsing Differentials to the Security Considerations
>> section is the administrative equivalent of putting a warning
>> label on a structurally flawed bridge instead of fixing the
>> engineering. If a design inherently allows two compliant parsers
>> to interpret the same wire format differently, the cryptographic
>> canonization is broken by design. This cannot be patched in
>> prose.
> 
> Are you objecting to recipes in general, or are you only objecting to 
> JSON-encoded recipes?
> 
> If the latter, please describe the parsing differential that occurs from 
> JSON-encoded recipes that would not also occur in any other encoding of 
> recipes.
> 
> If the former, then I don't see enough support for your objection to 
> consider the rough consensus to be broken.
> 
>> Regarding internal representation and y2k38: This is not about
>> internal code; it is about strict constraints on the wire format.
> 
> What text do you want to add to what section of what document?
> 
>> If a protocol aims to secure critical infrastructure...
> 
> Do you see DKIM as securing critical infrastructure? Please explain.
> 
>> ...running
>> legacy 32-bit hardware, leaving timestamp boundaries "out of
>> scope" is a known operational risk that flat, native types can
>> easily avoid.
> 
> What text do you want to add to what section of what document?
> 
>> Finally, defining Rough Consensus while bypassing the reality of
>> broken Running Code at the edge nodes degrades a core IETF
>> principle into theoretical debate.
> 
> This is not a discussion I'm willing to have on this list. I'll write to 
> you separately about this topic.
> 
>> You are confusing me. As editor of RFC 5322 you should be the
>> last one who supports complex JSON objects in mail headers.
> 
> As the editor of RFC 5322, I can tell you that the parsing differentials 
> between 5322 parsers make parsing differentials between JSON parsers 
> look downright quaint, and let's not even start down the path of MIME 
> parsing. You're going to have to come up with specific issues that are 
> of concern, not generalities, if you want to convince others on this 
> list that there is a problem worth considering. (And my thoughts as 
> editor of RFC 5322 are independent of my role as chair, which is to 
> judge the rough consensus on the list.)
> 
>> BTW: Bron already confirmed that this design would possibly not
>> work on Inbound Edge Gateways.
> 
> I'm not sure what you're referring to. Please cite a specific message. I 
> know Bron (among others) has said that some of the actions of inbound 
> edge gateways are not appropriate for recipes, but I have no idea how 
> that is relevant to the current discussion. Please provide context.
> 
> pr


Timo Gerke
Hamburg, Germany

"If you think technology can solve your security
 problems then you don't understand the problems
 and you don't understand the technology."
   -- Bruce Schneier

Attachment: OpenPGP_0x9F03DF9F597BF31E.asc
Description: OpenPGP public key

Attachment: OpenPGP_signature.asc
Description: OpenPGP digital signature

_______________________________________________
Ietf-dkim mailing list -- [email protected]
To unsubscribe send an email to [email protected]

Reply via email to