ietf-dkim
[Top] [All Lists]

Re: [ietf-dkim] Getting resolution on the "double header" issue

2010-11-11 12:32:22
rfc4871bis-02 Introduction:
,---
...
DKIM:

  o  is compatible with the existing email infrastructure and
       transparent to the fullest extent possible;

  o  requires minimal new infrastructure;

  o  can be implemented independently of clients in order to reduce
       deployment time;

  o  can be deployed incrementally;

  o  allows delegation of signing to third parties.
...
'---

DKIM establishes additional trust based upon a signature's domain, where 
DKIM MUST protect use of this trust without assuming  changes will be 
made to existing email infrastructure.  Some have suggested new 
mail-filtering should be added to MUAs, MTAs, and other mail agents to 
prevent exploits of DKIM trust allowed by DKIM's verification having 
neglected essential checks for multiple singleton header fields.

Once one DKIM verification vendor includes these necessary checks that 
suppress DKIM PASS, and another vendor does not, DKIM implementations 
are no longer compatible.  IMHO, this represents a DKIM protocol failure 
to properly define elements that MUST BE checked to qualify a DKIM PASS 
verification result.  The DKIM protocol may require future updates as 
new exploits are discovered, or a significant design goal will have been 
lost.

-Doug




_______________________________________________
NOTE WELL: This list operates according to 
http://mipassoc.org/dkim/ietf-list-rules.html